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Compound wind and precipitation extremes (CWPEs) can severely impact natural and socioeconomic systems. However, our understanding of CWPE future changes, drivers, and uncertainties under a warmer climate is limited. Here, by analyzing the event both on oceans and landmasses via state‐of‐the‐art climate model simulations, we reveal a poleward shift of CWPE occurrences by the late 21st century, with notable increases at latitudes exceeding 50° in both hemispheres and decreases in the subtropics around 25°. CWPE intensification occurs across approximately 90% of global landmasses, and is most pronounced under a high‐emission scenario. Most changes in CWPE frequency and intensity (about 70% and 80%, respectively) stem from changes in precipitation extremes. We further identify large uncertainties in CWPE changes, which can be understood at the regional level by considering climate model differences in trends of CWPE drivers. These results provide insights into understanding CWPE changes under a warmer climate, aiding robust regional adaptation strategy development. Plain Language Summary: Concurrent wind and precipitation extremes (CWPEs), a typical case of compound weather events, can cause flooding and strong winds that can paralyze public transportation, trigger power outages, and destroy houses and shelters. Furthermore, CWPE over the ocean can endanger the shipment of goods and its logistics. Yet, our understanding of the projected changes, underlying drivers, and uncertainties under a warmer climate is limited. Here, analyzing for the first time CWPEs both on global oceans and landmasses allows us to reveal a poleward shift of CWPEs at the global scale in response to climate change. We show that changes in precipitation extremes play a dominant role in determining the future changes in the frequency and intensity of CWPEs. Furthermore, at the regional level, we reveal substantial uncertainties in projections due to differences between the used climate models. We illustrate that these uncertainties are due to model differences in trends of CWPE drivers and argue that they should be addressed explicitly in impact assessments for guiding the development of robust adaptation strategies. Key Points: An intensification and poleward shift of compound wind and precipitation extremes (CWPEs) will occur in a warmer climateMost changes in frequency and intensity of CWPEs stem from changes in precipitation extremesSubstantial uncertainties at the regional level in projections of CWPEs are due to structural model differences [ABSTRACT FROM AUTHOR]

Strengthening aquatic resilience to prevent adverse shifts is critical for preserving global freshwater biodiversity and advancing Sustainable Development Goals. Nonetheless, understanding the long‐term trends and underlying causes of lake ecosystem resilience at a global scale remains elusive. Here, we employ an innovative framework, integrating satellite‐derived water quality indices with early warning signals and machine learning techniques, to investigate the dynamics of resilience in 1,049 lakes worldwide during 2000–2018. Our results indicate that 46.7% of lakes are experiencing a significant decline in resilience, particularly since the early 2010s, closely associated with higher human population density and anthropogenic eutrophication. In contrast, most lakes situated in alpine regions exhibit an increase in resilience, probably benefiting from climate warming and wetting. Together, this study provides a novel way to monitor lake resilience and predict undesired transitions, and reveals a widespread erosion in the ability of lakes to withstand stressors associated with global change. Plain Language Summary: Based on water quality data from satellite observation and generic indicators of ecological resilience, we found 46.7% of lakes worldwide are experiencing a significant decline in the ability to resist and recover from environmental disturbances. This issue is exacerbated in Northern Europe and Eastern North America, closely related to local human impacts, such as anthropogenic eutrophication. As the regional wealth grows, like in central North America, the negative impact of human activity on aquatic ecosystems may decrease. In contrast, in regions like the Tibetan Plateau and Andes Mountains, lakes are actually showing an increase in resilience, indicating that ecosystems may adapt to or even benefit from climate change. Our analysis' global scope allows us to better understand lake ecosystem dynamics and the socioeconomic drivers associated with them. This knowledge will help manage lakes' response to global change. Key Points: Over the last two decades (2000–2018), nearly half of global lakes experienced resilience lossLake resilience decline is closely linked to human activities in the catchmentsSatellite data effectively track early warning signals of lake resilience loss [ABSTRACT FROM AUTHOR]

The Vietnam upwelling is a crucial circulation feature in the South China Sea. Although previous studies have shown that various coastal upwellings around the world may intensify under global warming, future changes in the Vietnam upwelling remain unclear. To address this knowledge gap, we analyzed the long‐term trend in the Vietnam upwelling under a high‐emission scenario for the period 2006–2100, using simulation results from a global eddy‐resolving climate model. In this model, the summertime Vietnam upwelling is projected to intensify in the 21st century and is statistically significant between 12°N and 14°N. A volume flux budget analysis indicates that wind stress curl is the most important contributor to the intensification. The geostrophic flow, to some extent, may suppress the upwelling intensification. The projected increase in upwelling is shown to significantly reduce local ocean warming and freshening and thus may have vital impacts on the local climate and circulation. Plain Language Summary: The South China Sea is characterized by an intense upwelling to the east of the Vietnam coast. Prior studies have reported that global warming can significantly affect the global wind stress. Since the Vietnam upwelling is mainly caused by the prevailing southwesterly monsoon, a question arises naturally: whether this upwelling will intensify under the global warming. Using a global climate model with a horizontal resolution of ∼0.1°, we found that the summertime Vietnam upwelling was projected to increase by ∼1 m/day from the first 30 years to the last 30 years in the 21st century. The increase mainly results from an increase in the wind stress curl. The geostrophic flow can suppress the increase in upwelling; this finding is consistent with some prior studies. Moreover, this study showed that intensified upwelling can significantly reduce the increase in the local seawater temperature and the decrease in the local seawater salinity. Key Points: The Vietnam upwelling is projected to increase under a high‐emission scenarioThe wind stress curl dominates the long‐term change in the Vietnam upwellingIncreased upwelling may significantly affect local ocean warming and freshening [ABSTRACT FROM AUTHOR]

Amplification of sea surface temperature (SST) seasonality in response to global warming is a robust feature in climate model projections but season‐dependent regional disparities in this amplification and the associated mechanisms are not well addressed. Here, by analyzing large ensemble simulations using Community Earth System Model version 2, we investigate detailed spatiotemporal characteristics of the amplification of SST seasonality focusing on the North Pacific and North Atlantic, where robust changes are projected to emerge around 2050 under SSP3‐7.0 scenario. Our results indicate that atmosphere‐ocean coupled processes shape regional changes in SST seasonality differently between warm (MAMJJAS) and cold seasons (ONDJF). During the warm season, the projected warming tendency is mainly due to increased net surface heat flux and weakening of vertical mixing. On the other hand, in the cold season, the projected cooling tendency is driven by strengthened vertical mixing over the North Pacific associated with the northward shift of storm tracks but weakened horizontal advection and mixing due to changes in ocean currents over the North Atlantic. Plain Language Summary: In addition to the increase in annual mean sea surface temperature (SST), the amplitude of SST seasonal cycle is projected to intensify in response to greenhouse warming over many parts of the global ocean due to more warming during local summer than winter. By analyzing large ensemble simulations, we show how different atmospheric and ocean processes influence spatiotemporal differences in SST seasonality changes in the North Pacific and North Atlantic. Our findings indicate that during local summer, the projected warming tendency intensifies with the increased heat input into the ocean and weakening of ocean mixing. Meanwhile, during local winter, the projected cooling tendency intensifies with the strengthening of vertical mixing associated with the enhanced storm track activities in the North Pacific, but the weakening of ocean horizontal advection and mixing attributable to the weakened ocean circulation over the North Atlantic. They together contribute to the amplification of SST seasonality, which could have implications for marine ecosystems, including the plankton phenology. Key Points: Using CESM2 large ensemble simulations, this study explores the robustness of future sea surface temperature (SST) seasonality changes and the associated atmospheric and surface ocean processesIn the warm season, the future SST warming is mainly driven by the reduced upper ocean mixing and the increased net surface heat influx into the oceanIn the cold season, the future SST cooling is attributable to strengthened vertical mixing over the North Pacific but weakened horizontal advection and mixing in the North Atlantic [ABSTRACT FROM AUTHOR]

The impact of changes in global temperatures and precipitation on climate distribution remains unclear. Taking the annual global average temperatures and precipitation as the origin, this study determined the climate distribution with the distances of temperature and precipitation from their global averages as the X and Y axes. The results showed that during 1980–2019, the global temperature distribution converged toward the mean (convergence), while the precipitation distribution moved away from the mean (divergence). The combined effects of both led to a convergence in the global climate distribution. During 2025–2100, significant climate convergence is observed under two emission scenarios (SSP245 and SSP585). However, the climate convergence and the area of change in climate type remains insignificant only under SSP126, suggesting that the diversity of the global climate pattern can be maintained under a sustainable emission pathway (SSP126), whereas high emission pathways will lead to greater uniformity in global climate. Plain Language Summary: Global average temperatures and precipitation have increased significantly over recent decades. However, the distribution of affected areas remains unclear in comparison to the global mean. Taking annual temperature and precipitation averages as a reference point, this study measured temperature and precipitation anomalies from the global mean on the X and Y axes. The Euclidean distance of each grid cell represents its deviation (anomaly) from the global climate mean. These distances are termed the degree of deviation of temperature, precipitation, and climate from the global mean for each raster. The results reveal a discernible homogenization trend regarding the distribution of global climate. Among three distinct climate scenarios, climate diversity is effectively preserved under the low‐emission model (SSP126), whereas global climate distribution exhibits a substantial convergence toward the annual mean under the high‐emission models (SSP245 and SSP585). Key Points: Against the backdrop of global warming, the climate pattern is shifting toward convergenceTemperature is the primary driver behind climate convergence, while precipitation plays a central role in climate diversityLow‐level emissions are conducive to preserving the diversity of future global climate distribution [ABSTRACT FROM AUTHOR]

Diagnosing the role of internal variability over recent decades is critically important for both model validation and projections of future warming. Recent research suggests that for 1980–2022 internal variability manifested as Global Cooling and Arctic Warming (i‐GCAW), leading to enhanced Arctic Amplification (AA), and suppressed global warming over this period. Here we show that such an i‐GCAW is rare in CMIP6 large ensembles, but simulations that do produce similar i‐GCAW exhibit a unique and robust internally driven global surface air temperature (SAT) trend pattern. This unique SAT trend pattern features enhanced warming in the Barents and Kara Sea and cooling in the Tropical Eastern Pacific and Southern Ocean. Given that these features are imprinted in the observed record over recent decades, this work suggests that internal variability makes a crucial contribution to the discrepancy between observations and model‐simulated forced SAT trend patterns. Plain Language Summary: When comparing model simulations of Earth's recent warming to real‐world observations, differences may arise from several factors. Two important factors are the model errors in the simulated response to increased greenhouse gases, and natural fluctuations within the climate system that produced discrepancies between observations and models. Thus, quantifying the role of these natural fluctuations is important for the assessment of model‐observation differences. Previous studies have shown that natural climate variability has depressed global warming and enhanced Arctic warming. By compositing the multi‐decadal trend patterns from CMIP6 simulations in which natural variability warms the Arctic but has a global cooling effect, we find that the majority of these model simulations also produce enhanced warming in the Barents and Kara Seas and cooling in the Tropical Eastern Pacific and Southern Ocean due to natural variability. Since these are the exact features imprinted on observed surface temperature changes over 1980–2022, our work suggests that natural variability is an important component of several noteworthy differences between models and observations. Key Points: Internal variability has enhanced Arctic warming but suppressed global warming over 1980–2022This manifestation of internal variability is rare in model simulations but has a robust global surface air temperature (SAT) trend patternThis internal SAT pattern features warming in the Barents and Kara Sea and cooling of the Tropical Eastern Pacific and Southern Ocean [ABSTRACT FROM AUTHOR]

The role of internal variability in generating an apparent link between autumn Barents‐Kara sea (BKS) ice and the winter North Atlantic Oscillation (NAO) has been intensely debated. In particular, the robustness and causality of the link has been questioned by showing that BKS‐NAO correlations exhibit nonstationarity in both reanalysis and climate model simulations. We show that the lack of ice observations means nonstationarity cannot be confidently assessed using reanalysis prior to 1961. Model simulations are used to corroborate an argument that forced nonstationarity could result from ice edge changes due to global warming. Consequently, the observed change in BKS‐NAO correlations since 1960 might not be purely a result of internal variability and may also reflect that the ice edge has moved. The change could also reflect the availability of more accurate ice observations. We discuss potential implications for analysis based on coupled climate models, which exhibit large ice edge biases. Plain Language Summary: Does the amount of ice in the Barents‐Kara Sea influence European air pressure or are the patterns we see caused by random changes in the weather? In climate models and in estimates of the atmosphere's history these patterns change depending on which years we look at. This has been interpreted as evidence that the patterns are random. However, there are very few measurements of ice in this region before 1961, so we argue that looking at these years is not helpful. Since 1961, where we have more measurements, the winter sea ice edge has been moving Northwards because of global warming. When the ice in a particular region disappears, it changes the expected relationship with the atmosphere because heat can now quickly leave the ocean. We therefore hypothesize that some of the changes seen in the patterns may therefore not be random, but a result of ice edge changes. We also observe that different climate models put the ice edge in different places, and the same hypothesis therefore implies that models might not get potential ice‐air pressure relationships in specific regions correct. Key Points: A lack of observations means that ice‐NAO links cannot be confidently assessed with reanalysis prior to 1961Nonstationarity since 1961 may reflect forced changes to the ice edge, due to the dependence of heatflux anomalies on ice edge variabilityThe magnitude of this potential forced nonstationarity in the real world is currently unclear [ABSTRACT FROM AUTHOR]

The Somerset Levels and Moors, UK is an area of high conservation value, including nationally and internationally protected wetland sites. Duckweed (Lemna) mats in the Somerset Levels and Moors are increasingly common and are an indication of hyper-eutrophication. Duckweed mats can contribute to increased management burdens and decreases in biodiversity. Research suggests duckweed will thrive in temperate regions as the climate warms. This study investigated the impact of climate warming and eutrophication on duckweed growth in the Somerset Levels and Moors using a previously published model to simulate duckweed growth from the years of 2020–2080. Simulated local climate change projections and adjustments in actual nitrogen and phosphorus levels were used to estimate changes in biomass. Using the simulated data, the model predicted an 83% increase in biomass from the 2020's to the 2070's if nutrients do not change. In order to offset the impact of climate change on duckweed biomass, nutrient levels will need to decrease by more than 50% by 2080. Further changes to management practices will likely be necessary to restore healthy ecological function and biodiversity in the area. [ABSTRACT FROM AUTHOR]

The article discusses the need for mechanistic explanations in seed ecology and highlights the limitations of broad-scale correlative studies that ignore mechanisms. The authors specifically focus on seed dormancy and argue that the current understanding of seed dormancy as an adaptive response to climate seasonality is flawed. They propose that fire regime, rather than climate seasonality, is a more plausible mechanism for selecting prolonged seed dormancy. The article also mentions similar issues in other areas of ecology, such as species diversity and trait ecology, and emphasizes the importance of a mechanistic understanding and hypothesis-driven research. [Extracted from the article]

Environmental nonprofit organizations (ENPOs) play a critical role in climate governance. Though ENPOs dedicate significant efforts to advocacy and providing public services, their interaction with public opinion on global warming has not been fully explored. Through multilevel regression analysis on county-level data in the U.S., this article examines the relationship between the presence of ENPOs and public perceptions of global warming, taking into account variations among ENPOs. The findings indicate that: (1) the overall presence of ENPOs is slightly, but not significantly, positively correlated with public perceptions of global warming, with advocacy-oriented ENPOs showing a more robust and statistically significant correlation; (2) there is an inverted-U relationship between the presence of ENPOs and public opinion on global warming, with advocacy-oriented ENPOs reaching tipping points earlier than service-oriented ENPOs; and (3) the partisanship of liberal counties influences this association. This study suggests a potential role for nonprofits in policymaking by interacting with public opinion. [ABSTRACT FROM AUTHOR]

Ceracris kiangsu Tsai (C. kiangs) is a kind of forest pest, which can harm nearly 100 kinds of weeds and crops. In this study, based on 314 species distribution points of C. kiangsu which were obtained from Chinese herbaria, literatures and investigation, and data of three future climate scenarios presented by CMIP6, two niche models (Garp, Maxent) were used to predict the suitable area of C. kiangsu in China. The result shows that the main environmental factors affecting the distribution of C. kiangsu are precipitation of driest month (bio14) and min temperature of coldest month (bio6). No matter now and future, the potential distribution areas of C. kiangsu in China are mainly in the south of Qinling–Huaihe River. Under current scenarios, the areas of the total, highly, moderately and poorly suitable of C. kiangsu in China are 160.65 × 104 km2, 31.70 × 104 km2, 60.36 × 104 km2 and 68.59 × 104 km2 respectively. The southern Hubei, western Jiangxi and eastern Hunan are highly-suitable areas. Under SSP1-2.6 and SSP2-4.5 scenarios, both the total suitable area and the highly suitable show a decreasing tread in 2050s. Compared to the 2050s, the total suitable area will coninue to decease in 2090s under SSP1-2.6, while it will increase under SSP2-4.5. The highly suitable area will increase in both scenarios, and the increased percentage under SSP2-4.5 is greater than that under SSP1-2.6. Under SSP5-8.5 scenarios, the total suitable area will increase by 1.83% in the 2050s, and decrease by 1.17% in the 2090s. The highly suitable area in the 2050s and 2090s under this scenarios is larger than under current scenarios. No matter what the scenario, the southern part of Yunnan, the southeast of Sichuan and the southwest of Chongqing will become highly-suitable areas as the climate continues to warm and should be monitored more cosely. [ABSTRACT FROM AUTHOR]

Due to high environmental temperatures and climate change, heat stress is a severe concern for poultry health and production, increasing the propensity for food insecurity. With climate change causing higher temperatures and erratic weather patterns in recent years, poultry are increasingly vulnerable to this environmental stressor. To mitigate heat stress, nutritional, genetic, and managerial strategies have been implemented with some success. However, these strategies did not adequately and sustainably reduce the heat stress. Therefore, it is crucial to take proactive measures to mitigate the effects of heat stress on poultry, ensuring optimal production and promoting poultry well-being. Embryonic thermal manipulation (TM) involves manipulating the embryonic environment's temperature to enhance broilers' thermotolerance and growth performance. One of the most significant benefits of this approach is its cost-effectiveness and saving time associated with traditional management practices. Given its numerous advantages, embryonic TM is a promising strategy for enhancing broiler production and profitability in the poultry industry. TM increases the standard incubation temperature in the mid or late embryonic stage to induce epigenetic thermal adaption and embryonic metabolism. Therefore, this review aims to summarize the available literature and scientific evidence of the beneficial effect of pre-hatch thermal manipulation on broiler health and performance. [ABSTRACT FROM AUTHOR]

Under a warming climate, occurrences of wildfires have been increasingly more frequent in boreal and arctic forests during the last few decades. Wildfires can cause radical changes in the forest ecosystems and permafrost environment, such as irreversible degradation of permafrost, successions of boreal forests, rapid and massive losses of soil carbon stock, and increased periglacial geohazards. Since 2016, we have gradually and more systematically established a network for studying soil nutrients and monitoring the hydrothermal state of the active layer and near-surface permafrost in the northern Da Xing'anling (Hinggan) Mountains in Northeast China. The dataset of soil moisture content (0–9.4 m in depth), soil organic carbon (0–3.6 m), total nitrogen (0–3.6 m), and total phosphorus and potassium (0–3.6 m) have been obtained by field sampling and ensuing laboratory tests. Long-term datasets (2017–2022) of ground temperatures (0–20 m) and active layer thickness have been observed by thermistor cables permanently installed in boreholes. The present data can be used to simulate changes in permafrost features under a changing climate and wildfire disturbances and to explore the changing interactive mechanisms of the fire-permafrost-carbon system in the hemiboreal forest. Furthermore, can provide baseline data for studies and action plans to support the carbon neutralization initiative and assessment of ecological safety and management of the permafrost environment. This dataset can be easily accessed from the National Tibetan Plateau/Third Pole Environment Data Center (https://doi.org/10.11888/Cryos.tpdc.300933 , Li and Jin, 2024). [ABSTRACT FROM AUTHOR]

Simply expressed, the circular economy implies that the people living on Earth should reuse and recycle the products that are currently in use as long as possible and reduce the waste produced, thus reducing CO2 emissions. The latter goal is fundamental from the perspective of mitigating the well-known greenhouse effect and the consequent global warming observed at the planetary scale. Under these conditions, advanced electrodeposition processes can play a fundamental role in the optimization of materials use and in the reduction of the energetic footprint for a wide variety of industrial processes. The aim of the present paper is precisely to suggest how this is possible, showing readers the potential that electrodeposition holds for efficient manufacturing of many different products that have a huge significance for industry. [ABSTRACT FROM AUTHOR]

Evaporative water concentration takes place in arid or semi-arid environments when stationary water bodies, such as lakes or ponds, prevalently lose water by evaporation, which prevails over outflow or seepage into aquifers. Absence or near-absence of precipitation and elevated temperatures are important prerequisites for the process, which has the potential to deeply affect the photochemical attenuation of pollutants, including contaminants of emerging concern (CECs). Here we show that water evaporation would enhance the phototransformation of many CECs, especially those undergoing degradation mainly through direct photolysis and triplet-sensitized reactions. In contrast, processes induced by hydroxyl and carbonate radicals would be inhibited. Our model results suggest that the photochemical impact of water evaporation might increase in the future in several regions of the world, with no continent likely being unaffected, due to the effects of local precipitation decrease combined with an increase in temperature that facilitates evaporation. [ABSTRACT FROM AUTHOR]

Global warming has caused such problems as the poor coloration of grape skin and the decreased production of high-quality berries. We investigated the effect of synephrine (Syn) on anthocyanin accumulation. Anthocyanin accumulation in cultured grape cells treated with Syn at concentrations of 1 mM or higher showed no significant difference, indicating that the accumulation was concentration-independent. On the other hand, anthocyanin accumulation was dependent on the compound used for treatment. The sugar/acid ratio of the juice from berries treated with Syn did not differ from the control. The expression of anthocyanin-biosynthesis-related genes, but not phytohormones, was increased by the treatment with Syn at 24 h or later. The Syn treatment of cultured cells increased SOD3 expression and hydrogen peroxide (H2O2) production from 3 to 24 h after treatment. Subsequently, the expression of CAT and APX6 encoding H2O2-scavenging enzymes was also increased. Treatment of cultured cells with Syn and H2O2 increased the expression of the H2O2-responsive gene Chit4 and the anthocyanin-biosynthesis-related genes mybA1 and UFGT 4 days after the treatment and increased anthocyanin accumulation 7 days after the treatment. On the other hand, the treatment of berries with Syn and H2O2 increased anthocyanin accumulation after 9 days. These results suggest that Syn increases anthocyanin accumulation through H2O2 production without changing phytohormone biosynthesis. Syn is expected to improve grape skin coloration and contribute to high-quality berry production. [ABSTRACT FROM AUTHOR]

Simple Summary: Pigs lack functional sweat glands, hence being very susceptible to heat stress. The optimum temperature in which pigs would thrive is around 20 °C, depending on age and weight. Pigs could achieve higher heat dissemination, e.g., by increasing body contact with the cooler ground and panting, but also through an undesirable reduction in feed intake. In addition, under conditions of severe heat stress, animals may become more susceptible even to immune challenges due to damage to the structure of the intestinal wall. Thus, heat stress can affect the proper functioning of metabolism, which, in addition to having implications on animal welfare, also affects the quality of meat and meat products. Cooling systems are not yet commonly seen on farms. Sprinkler systems are the most used cooling system, followed by water pads and fogging systems, for finishing pigs. As our climate continues to warm, monitoring daily feed intake and water consumption levels, along with the implementation of cooling systems, must become tools to minimize the adverse effects of hot weather. Heat stress is a significant environmental problem that has a detrimental impact on animal welfare and production efficiency in swine farms. The current study was conducted to assess the effect of low-intensity showers, provided during critical high-temperature hours daily, on body external temperature, feeding pattern, and carcass and meat quality characteristics in fattening pigs. A total of 400 animals (200 barrows and 200 gilts) were randomly allotted in 40 pens. A shower nozzle was installed over 20 pens (half barrows and half gilts) where pigs received a low-intensity shower for 2 min in 30 min intervals from 12 to 19 h (SHO group). Another group without showers was also considered (CON). Feeder occupancy measurement, thermographic measures, and carcass and meat quality parameters were studied. In the periods with higher environmental temperatures, SHO animals showed an increase in the feeder occupancy rate compared to the CON group. A decrease in temperature was observed after the shower, regardless of the anatomical location (p < 0.005). The treatment with showers led to higher values than in the CON group of 4.72%, 3.87%, 11.8%, and 15.1% for hot carcass weight, lean meat yield, and fat thickness in Longissimus Dorsi (LD) and Gluteus Medius muscles, respectively (p < 0.01). Pork from CON showed a 14.9% higher value of drip loss, and 18.9% higher malondialdehyde concentration than SHO (p < 0.01); meanwhile, intramuscular fat content was 22.8% higher in SHO than in CON (p < 0.01). On the other hand, the CON group exhibited higher L* (2.13%) and lower a* and b* values (15.8% and 8.97%) compared to the SHO group. However, the pH20h of the CON group was significantly lower than that of the SHO group (p < 0.001), indicating a softer pH decrease. Related to fatty acids in subcutaneous outer and inner layers and intramuscular fat, the CON group showed higher ΣSFA and lower ΣMUFA and Δ9-desaturase indexes than SHO (p < 0.05). In conclusion, the amelioration of heat stress through showers at critical times should be considered an interesting tool that improves both carcass and meat quality, as well as animal welfare. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence primarily originates from abrupt density variations in a vertically stratified atmosphere. Based on the prognostic equation of turbulent kinetic energy (TKE), we here chose three indicators corresponding to the forcing terms of the TKE generation. By utilizing ERA5 reanalysis data, we investigate first the maximum achievable daily thickness of the planetary boundary layer (PBL). The gradient Richardson number (Ri) is used to represent turbulence arising from shear instability and the daily maximum convective available potential energy (CAPE) is examined to understand the turbulence linked with convective instability. Our analysis encompasses global turbulence trends. As a case study, we focus on the North Atlantic Corridor (NAC) to reveal notable insights. Specifically, the mean annual number of hours featuring shear instability (Ri < 0.25) surged by more than 300 h in consecutive 20-year periods: 1979–1998 and 1999–2018. Moreover, a substantial subset within the NAC region exhibited a notable rise of over 10% in the number of hours characterized as severe shear instability. Contrarily, turbulence associated with convective instability (CAPE > 2 kJ/kg), which can necessitate rerouting and pose significant aviation safety challenges, displays a decline. Remote sensing of clouds confirms these assertions. This decline contains a component of inherent natural variability. Our findings suggest that, as air viscosity increases and hence a thickened PBL due to a warming climate, the global inflight turbulence is poised to intensify. [ABSTRACT FROM AUTHOR]

The phytoplankton size structure exerts a significant influence on ecological processes and biogeochemical cycles. In this study, the interannual variations in remotely sensed phytoplankton size structure in the southern Tropical Indian Ocean (TIO) and the underlying physical mechanisms were investigated. Significant interannual fluctuations in phytoplankton size structure occur in the southeastern TIO and central southern TIO and are very sensitive to Indian Ocean Dipole (IOD) events. During positive IOD events, the southeast wind anomalies reinforce coastal upwelling off of Java and Sumatra, leading to a shift toward a larger phytoplankton structure in the southeastern TIO. The anomalous anticyclonic circulation deepened the thermocline and triggered the oceanic downwelling Rossby waves, resulting in a smaller phytoplankton structure in the southwestern TIO. During the decay phase of the strong positive IOD events, the sustained warming in the southwestern TIO induced basin-wide warming, thereby maintaining such an anomalous phytoplankton size structure into the following spring. The response of phytoplankton size structure and ocean dynamics displayed inverse patterns during the negative IOD events, with an anomalous larger phytoplankton structure in the central southern TIO. These findings enhance our understanding of phytoplankton responses to climate events, with serious implications for ecosystem changes in a warming climate. [ABSTRACT FROM AUTHOR]

Coastal areas are among the most productive areas in the world, ecologically as well as economically. Sea Surface Temperature (SST) has evolved as the major essential climate variable (ECV) and ocean variable (EOV) to monitor land–ocean interactions and oceanic warming trends. SST monitoring can be achieved by means of remote sensing. The current relatively coarse spatial resolution of established SST products limits their potential in small-scale, coastal zones. This study presents the first analysis of the TIMELINE 1 km SST product from AVHRR in four key European regions: The Northern and Baltic Sea, the Adriatic Sea, the Aegean Sea, and the Balearic Sea. The analysis of monthly anomaly trends showed high positive SST trends in all study areas, exceeding the global average SST warming. Seasonal variations reveal peak warming during the spring, early summer, and early autumn, suggesting a potential seasonal shift. The spatial analysis of the monthly anomaly trends revealed significantly higher trends at near-coast areas, which were especially distinct in the Mediterranean study areas. The clearest pattern was visible in the Adriatic Sea in March and May, where the SST trends at the coast were twice as high as that observed at a 40 km distance to the coast. To validate our findings, we compared the TIMELINE monthly anomaly time series with monthly anomalies derived from the Level 4 CCI SST anomaly product. The comparison showed an overall good accordance with correlation coefficients of R > 0.82 for the Mediterranean study areas and R = 0.77 for the North and Baltic Seas. This study highlights the potential of AVHRR Local Area Coverage (LAC) data with 1 km spatial resolution for mapping long-term SST trends in areas with high spatial SST variability, such as coastal regions. [ABSTRACT FROM AUTHOR]

This study analyzes the temporal patterns of rainfed cereal phenology extracted from the GIMMS NDVI3g dataset in the main cereal-growing regions under a Mediterranean climate in Spain, Portugal, France and Italy during the period 1982–2022. The series before and after the beginning of the 21st century were analyzed separately. Phenological parameters were extracted using the modified dynamic threshold method, and their trends were analyzed. Correlation analyses were performed to study the relationships among these parameters and to analyze the influence of hydroclimatic variables on the start (SOS) and end (EOS) of the growing season. Results showed a temporal reversal in phenological trends between both study periods, coinciding with the global warming hiatus. In the first period (1982–2002), SOS and EOS advanced (−7.5 and −3.1 days, respectively), and the length of growing season (LOS) increased. However, during the second stage (2003–2022), SOS and EOS were delayed (7.5 and 1.7 days, respectively), and LOS decreased. Similar dynamics were observed for the influence of the hydroclimatic variables on SOS and EOS, stronger in the first period and weaker in the second. This study provides valuable information on the phenological dynamics of rainfed cereals that may be useful for their management and planning in climate change scenarios. [ABSTRACT FROM AUTHOR]

Evapotranspiration (ET) is the most significant constituent of the response to climate warming. It serves as a crucial link in the soil–vegetation–atmospheric continuum. Analyzing the driving forces and response of ET to regional-scale climate warming holds scientific significance in improving global water resource assessment methods and drought monitoring techniques. The innovation presented in this article is the calculation of ET by using GRACE/GRACE-FO satellite data through the water balance equation. The inter-annual and seasonal changes in ET in different regions of the Qilian Mountains were analyzed, along with quantifying the contribution of environmental meteorological factors to ET. The ETGRACE and ETMonitor products have good consistency, with a monthly correlation coefficient of 0.92, an NSE coefficient of 0.80, and a root mean square error of 10.38 mm. The results indicate that the increasing trend of ET in the Qilian Mountains region exhibits a "medium–high–low" distribution pattern. The rate of increase in ET is 5.2 mm/year in the central segment. In spring and summer, the overall trend of ET is an increasing one. However, the central and western segments exhibit a slight decreasing trend of ET in autumn. During winter, the southern part of the Qilian Mountains experiences a notable reduction in ET. The correlation between the changes in ET and soil moisture exhibited a strong association, with soil moisture change contributing significantly to ET: 57.8% for the eastern section, 52.8% for the middle section, and 46.9% for the western section. The thermal effect primarily controls ET variations within eastern sections, where temperature change accounts for approximately 6.7% of the total variation in ET levels. Conversely, the moisture factor dominates western sections, where precipitation change accounts for about 6.5% of the total variation in ET levels. Due to the distinct gradient characteristics of environmental meteorological factors in the central segment, the fluctuation of these factors collaboratively drives ET changes. This article provides a new approach for obtaining continuous and reliable actual evapotranspiration in high-altitude areas. [ABSTRACT FROM AUTHOR]

Climate warming hampers grassland growth, particularly in dryland regions. To preserve robust grassland growth and ensure the resilience of grassland in these arid areas, a comprehensive understanding of the interactions between vegetation and climate is imperative. However, existing studies often analyze climate–vegetation interactions using concurrent vegetation indices and meteorological data, neglecting time-lagged influences from various determinants. To address this void, we employed the random forest machine learning method to predict the grassland NDVI (Normalized Difference Vegetation Index) in Asian drylands (including five central Asia countries, the Republic of Mongolia, and Parts of China) from 2001 to 2020, incorporating time-lag influences. We evaluated the prediction model's performance using three indexes, namely the coefficient of determination (R2), root-mean-square error (RMSE), and Mean Absolute Error (MAE). The results underscore the superiority of the model incorporating time-lag influences, demonstrating its enhanced capability to capture the grassland NDVI in Asian drylands (R2 ≥ 0.915, RMSE ≤ 0.033, MAE ≤ 0.019). Conversely, the model without time-lag influences exhibited relatively poor performance, notably inferior to the time-lag-inclusive model. The latter result aligns closely with remote sensing observations and more accurately reproduces the spatial distributions of the grassland NDVI in Asian drylands. Over the study period, the grassland NDVI in Asian drylands exhibited a weak decreasing trend, primarily concentrated in the western region. Notably, key factors influencing the grassland NDVI included the average grassland NDVI in the previous month, total precipitation in the current month, and average soil moisture in the previous month. This study not only pioneers a novel approach to predicting grassland growth but also contributes valuable insights for formulating sustainable strategies to preserve the integrity of grassland ecosystems. [ABSTRACT FROM AUTHOR]

The European Mediterranean Basin (Euro-Med), a region particularly vulnerable to global warming, notably lacks research aimed at assessing and enhancing the widely used remote climate detection products known as General Circulation Models (GCMs). In this study, the proficiency of GCMs in replicating reanalyzed 1981–2010 temperature data sourced from the ERA5 Land was assessed. Initially, the least data-modifying interpolation method for achieving a resolution match of 0.1° was ascertained. Subsequently, a pixel-by-pixel evaluation was conducted, employing five goodness-of-fit metrics. From these metrics, we compiled a Comprehensive Rating Index (CRI). A Multi-Model Ensemble using Random Forest was constructed and projected across three emission scenarios (SSP1-RCP2.6, SSP2-RCP4.5, and SSP5-RCP8.5) and timeframes (2026–2050, 2051–2075, and 2076–2100). Empirical Bayesian Kriging, selected for its minimal data alteration, supersedes the commonly employed Bilinear Interpolation. The evaluation results underscore MPI-ESM1-2-HR, GFDL-ESM4, CNRM-CM6-1, MRI-ESM2-0, CNRM-ESM2-1, and IPSL-CM6A-LR as top-performing models. Noteworthy geospatial disparities in model performance were observed. The projection outcomes, notably divergent from IPCC forecasts, revealed a warming trend of 1 to over 2 °C less than anticipated for spring and winter over the medium–long term, juxtaposed with heightened warming in mountainous/elevated regions. These findings could substantially refine temperature projections for the Euro-Med, facilitating the implementation of policy strategies to mitigate the effects of global warming in vulnerable regions worldwide. [ABSTRACT FROM AUTHOR]

The last deglaciation is considered a key period for exploring the underlying dynamics of temperature changes because it was characterized by multiple millennial-scale abrupt climatic events. However, the limited number of quantitative temperature records in Northeast (NE) China covering the last deglaciation hampers a complete understanding of the mechanisms and processes behind the temperature changes that occurred in that region. Here, we present a quantitative reconstruction of summer temperature over the last deglaciation based on bacterial branched glycerol dialkyl glycerol tetraethers (brGDGTs) analyzed from the sediment sequence of Lake Kielguo, a small volcanic lake in NE China. The results show that summer temperature was lowest during the interval ca. 20–18.2 calibrated (cal.) k.y. B.P. with a value of ∼11.1 °C and increased by ∼1.9 °C during Heinrich Stadial 1 (HS1) and by ∼2.7 °C during the transition to the Bølling-Allerød (B-A). The summer temperatures during the B-A warm interval and Younger Dryas cold interval were ∼14.1 °C and ∼12.0 °C, respectively. The summer temperature record from the Lake Kielguo sediment sequence indicates that summer warming dominated the climate change state during HS1 in East Asia, which is different from the cooling pattern controlled by winter temperatures in the North Atlantic and Greenland realms. This distinction can be explained by weakened winter cooling signals triggered by the collapse of Atlantic Meridional Overturning Circulation when these signals propagated to East Asia, and increased summer temperature warming controlled by orbital and greenhouse gases during HS1 in East Asia. [ABSTRACT FROM AUTHOR]

Basic ecological theory suggests that a tradeoff between competitiveness and stress tolerance dictates species range limits at regional extents. However, empirical support for this key theory remains deficient because the necessary spatial and temporal coverage and scalability of field observations has rarely been achieved. We harnessed an extensive dendroecological network (> 22 000 tree‐ring samples from 816 forest inventory plots) to disentangle competition‐limited from climate‐limited growth in both overstory and understory trees. Growth synchrony among trees thereby served as an integral metric of climate sensitivity, an approach that we justify in supplementary analyses of growth responses to temperature, precipitation, and the standardized precipitation‐evapotranspiration index. Sampling plots were arranged along elevational climate and vegetation gradients throughout the Carpathian Mountains, ranging from mixed‐species lowland forests to coniferous forests at high elevations. With mixed‐effect modelling, we also identified non‐climatic factors (stand characteristics, species diversity, and disturbance history) that modulate spatial patterns in the growth rate and synchrony of European beech Fagus sylvatica and Norway spruce Picea abies. Beech exhibited reduced growth and increased climate sensitivity towards higher elevations but performed better when species diversity was higher. The growth of spruce increased towards its lower range boundary, but understory cohorts grew poorly under interspecific competition. Overall, climate sensitivity was lower in more productive stands with benign climatic conditions and in recently disturbed sites with reduced stand density. These contrasting performances at mid‐elevations where the two species overlap (900–1300 m a.s.l.) reflect their evolutionary history, which enables them to be competitive (beech) or cold‐stress tolerant (spruce). This history will affect interactions between the two species under climate warming and shape macroecological patterns in the Carpathian ecoregion and likely other parts of Europe. Our findings point to a growing advantage of competitively stronger species in montane and subalpine vegetation zones. [ABSTRACT FROM AUTHOR]

Each winter, purpose‐built outdoor skating rinks are constructed in backyards and community parks across much of Canada and the northern United States. Past research projects that warmer winters will make it increasingly difficult to build outdoor rinks without artificial refrigeration. Here we build upon previous studies by mapping areas of North America where present average January temperatures are generally suitable each year for building outdoor rinks, and how this area will change by the 2050s and 2080s. Using projections from downscaled general circulation models, we show how under current emissions pathways, average January temperatures will become too mild by the 2050s to build outdoor rinks across much of eastern North America in most winters, and this area will expand by the 2080s to include most of the western United States. Under high emissions scenarios (RCP 8.5), unsuitably mild January temperatures expand to include densely populated areas of Canada's Prairie provinces by the 2080s. In short, many North Americans who build outdoor rinks every winter will, by mid‐century, be living in areas where temperatures are only cold enough to do so occasionally, creating a range of social, cultural, and health implications for people living in those regions. Key messages: By the 2050s, average January temperatures across much of eastern North America will be too mild to construct and maintain outdoor skating rinks in most winters.Under high emissions scenarios, by the 2080s January temperatures will become too mild for annual construction of outdoor skating rinks in almost all of the lower 48 US states and much of the Canadian prairies.Outdoor skating provides many significant social, cultural, and health benefits that will be lost as purpose‐built rinks become increasingly rare. [ABSTRACT FROM AUTHOR]

Increasing ocean temperature will speed up physiological rates of ectotherms. In fish, this is suggested to cause earlier spawning due to faster oocyte growth rates. Over time, this could cause spawning time to become decoupled from the timing of offspring food resources, a phenomenon referred to as trophic asynchrony. We used biological data, including body length, age, and gonad developmental stages collected from >125,000 individual Northeast Arctic cod (Gadus morhua) sampled between 59 and 73° N in 1980–2019. Combined with experimental data on oocyte growth rates, our analyses show that cod spawned progressively earlier by about a week per decade, partly due to ocean warming. It also appears that spawning time varied by more than 40 days, depending on year and spawning location. The significant plasticity in spawning time seems to be fine‐tuned to the local phytoplankton spring bloom phenology. This ability to partly overcome thermal drivers and thus modulate spawning time could allow individuals to maximize fitness by closely tracking local environmental conditions important for offspring survival. Our finding highlights a new dimension for trophic match–mismatch and should be an important consideration in models used to predict phenology dynamics in a warmer climate. [ABSTRACT FROM AUTHOR]

Climate change has profound impacts on ecosystems, and one critical aspect is its effect on seed germination, a crucial stage in plant life cycles. Various studies have explored the responses of plant species to rising temperatures, and there is now a pressing need to integrate this wealth of information into a coherent framework. The aim of this study was to survey literature about seed traits and thence to evaluate germination responses to climate change and to propose functional groups for germination. Increased temperature affects seed traits, particularly germinability. Many species show increased germination percentages in warmer temperatures, although the extent varies among species and temperature ranges. Some maintain a consistent percentage, whereas others reduce it to retain seeds in the seed bank. Temperature changes also affect the timing and season of germination, with some species accelerating germination, others delaying it, thereby influencing competition and exposure to adverse conditions. Shifts in temperature can alter seed requirements, affecting responses to temperature, humidity, light, chemical stimuli, and dormancy. Modifications in germination have profound effects on seed bank and seedling bank dynamics, affecting plant populations and ecological community resilience. Changes in germination can disrupt competitive dynamics, favoring some over others, altering community composition, and potentially impairing ecosystem functionality. Germination niche, germination potential, and germination phenology are fundamental concepts in the evaluation of climate change's implications for germination. [ABSTRACT FROM AUTHOR]

We describe a method for quantifying the contribution of climate change to local monthly, seasonal, and annual mean temperatures for locations where long observational temperature records are available. The method is based on estimating the change in the monthly mean temperature distribution due to climate change using CMIP6 (Coupled Model Intercomparison Project Phase 6) model data. As a case study, we apply the method to the record‐warm September 2023 in Helsinki, and then briefly examine all record‐warm months of the 21st century. Our results suggest that climate change made the record‐warm September in Helsinki 9.4 times more likely and 1.4°C warmer. Thus, the new monthly mean record in September 2023 would probably not have been set without the observed global warming. The presented and provided tool allows operational meteorologists and climatologists to monitor and report the impact of climate change on local temperatures in near real time. [ABSTRACT FROM AUTHOR]

Observations show that mesospheric clouds (MCs) have been increasing in recent decades, presumably due to increased mesospheric water vapor which is mainly caused by greater methane (CH4) oxidation in the middle atmosphere. Past warm climates such as those of the early Cretaceous and Paleogene periods are thought to have had higher CH4 concentrations than present day, and future CH4 concentrations will also likely continue to rise. Here, idealized atmosphere chemistry‐climate model experiments forced with strong polar‐amplified sea‐surface temperatures and elevated carbon dioxide (CO2) and CH4 concentrations predict a substantial spreading of MCs to middle and low latitudes, well beyond regions where they are currently found. Sensitivity tests show that increased water vapor from CH4 oxidation and cooling from increased CO2 and CH4 concentrations create favorable conditions for cloud formation, producing MC fractions of 0.02 in the low latitudes and 0.1 in the mid‐latitudes in the Northern Hemisphere when CH4 concentration is 16× higher than pre‐industrial. Further increases in CH4 result in a monotonic increase in low‐ and mid‐latitude MCs. A uniform surface ocean warming, changes in polar amplification, or the solar constant do not significantly affect our results. While the appearance of these clouds is interesting, their ice and liquid water content is not sufficient to cause a significant radiative effect. On the other hand, dehydration of the mesosphere due to these low‐ and mid‐latitude MCs could potentially lead to a reduction in atomic hydrogen, thereby affecting mesospheric ozone concentration, although further study is required to confirm this. [ABSTRACT FROM AUTHOR]

Garnacha variety is one of the most important red Mediterranean grape cultivars grown in the world. However, it may not reach optimum chromatic characteristics in warm climates such as Andalusia (Southern Spain). This study analyses the impact of the application of microwaves over the crushed grapes (MW) at laboratory scale over two vintages on the characteristics of Garnacha wines elaborated from grapes cultivated in a warm climate as an additional procedure to traditional red winemaking (CT) to obtain highly coloured wines. Oenological and colour parameters were measured to determine the effects of this treatment on wines throughout the winemaking process. Overall, wines made by MW had a higher phenolic content and colour intensity. The analysis of the detailed composition of the wine showed that the treatment with microwaves before the alcoholic fermentation leads to important differences in its colour properties. Thus, the treatment with microwaves induced easily perceptible changes in CIELab coordinates (lower L* and higher a* and C*ab values than CT). Additionally, it also showed to be significantly effective to increase the extraction of phenolic compounds from grape solids into grape juice, both globally (total polyphenol index and Folin–Ciocalteu index), and particularly regarding flavanols and flavonols content. Most of the above-mentioned significant differences remained with ageing. The reported results are promising and the treatment with microwaves in the optimized conditions seems a feasible auxiliary alternative in warm climates, where wines produced from some red grape cultivars often show suboptimal colour characteristics. [ABSTRACT FROM AUTHOR]

This study focuses on the investigation of the electromagnetic properties of multiphase inorganic materials (i.e., soils) in changing subsurface environmental conditions that are induced by climate warming. Subsurface warming in cold regions exacerbates the spatial and temporal evolution of frozen soil properties; therefore, an accurate characterization of the unfrozen water and ice content of frozen soils under different thermal conditions has become a pressing need. Several studies focused on the effect of the initial hydraulic properties on the electromagnetic properties of soils. However, detailed systematic studies on the influence of the combined effects of temperature, initial degree of saturation, applied frequency fields, and experiment scales are limited. This study aims to characterize the dielectric and electrical behavior of ice-bearing inorganic soils under the coupled effects of thermal, hydraulic, and electromagnetic conditions. A series of laboratory experiments were performed on soil samples that had different initial degrees of saturation and dry density values by electromagnetic impedance spectroscopy (EIS) and time domain reflectometry (TDR) between −10°C and 5°C. The results from the experiments revealed that the dielectric constant of the inorganic soils decreased with increasing frequency, decreasing initial volumetric water content (VWC), and temperature. The electrical resistivity values decreased with increasing frequency values, initial water content, and temperatures. In addition, the unfrozen water contents at different temperatures were calculated using a modified power law that accounts for the temperature-dependent dielectric permittivity of water and was compared with the TDR measurements. The outcomes of this study could help elucidate the intricate mechanisms of the particle–water–ice interface and their influence on the behavior of frozen soils that are needed for sustainable built and natural environments in cold regions. [ABSTRACT FROM AUTHOR]

Global warming is causing unprecedented changes to permafrost regions with amplified effects in the Arctic through a phenomenon known as Arctic amplification. This intensified climate warming thaws both the discontinuous and continuous permafrost resulting in changes in the mechanical properties of the soils found in these regions. Since permafrost regions constitute nearly 24% of the Northern Hemisphere, understanding the strength of soils in thawed conditions is essential to analyze the stability of existing structures, and to design safer and more economical infrastructure in these regions. Specifically, thawing of the permafrost is causing considerable reductions in its strength of soils, which may lead to massive landslides, foundation failures, and so forth. Since frozen soil is a multiphase structure that consists of soil particles, unfrozen water, ice, and air, each constituent will influence the mechanical properties. This paper reviews the current state of knowledge of the impact of temperature, volumetric ice content, unfrozen water content, and frozen density on the compressive strength, peak shear strength, residual shear strength, undrained shear strength, and tensile strength of soils. The undrained shear strength of soil is said to have a linear correlation with temperature. In addition, the undrained cohesion of soil was found to depend on the temperature, whereas the undrained friction angle of soil was significantly influenced by volumetric ice content. An increase in the volumetric ice content up to 80% to 90% will cause a reduction in the peak and residual deviatoric stresses. In addition, an increase in volumetric ice content resulted in an increase in the compressive strength of the soil. The tensile and compressive strengths were found to be functions of the unfrozen water content. Global warming is causing the temperature of the permafrost, which is permanently frozen ground, to rise. This paper provides valuable insights into the impact of the changes in this ambient temperature on the strength of frozen soils in permafrost regions for a wide range of applications. Such insights are crucial for the design of resilient and stable infrastructure, such as foundations, embankments, and retaining walls, in which consideration of the reduced strength of thawed soils due to climate change will be necessary. In addition, the knowledge will allow for better management of vulnerable areas prone to landslides and erosion caused by the weakened soil strength permitting the implementation of mitigation measures before lives are lost and costly economic damages are incurred. Finally, this information will aid in early warning systems, emergency planning, and decision making to minimize the impact of hazards on human settlements and infrastructure. In this paper, a review of the current state of knowledge regarding the strength of frozen soils and the associated fluctuations in these strengths because of a rise in temperature are presented. Guidelines on the best practices for sample preparation and testing along with correlations to estimate various strength parameters are also provided. [ABSTRACT FROM AUTHOR]

Aim: Species responses to global warming will depend on intraspecific diversity, yet studies of factors governing biogeographic patterns of variability are scarce. Here, we investigate the evolutionary processes underlying genetic and phenotypic diversity in the flightless and cold‐adapted grasshopper Sigaus piliferus, and project its suitable space in time. Location: Te Ika‐a‐Māui Aotearoa—North Island of New Zealand. Methods: We used mitochondrial sequences to investigate population connectivity and demographic trends using phylogeographic tools and neutrality statistics. Metric data were used to document phenotypic variation using naïve clustering. We used niche metrics to assess intraspecific niche variation, and niche modelling to investigate suitability under past and future scenarios. Multiple matrix regressions with randomization explored the processes contributing to phenotypic differentiation among grasshopper populations. Results: Niche models and demographic analyses suggest suitable space for this grasshopper was more restricted during glacial than interglacial stages. Genealogical relationships among ND2 haplotypes revealed a deep north–south split partly concordant with phenotypic and niche variation, suggesting two ecotypes that have mixed during recolonisation of the central volcanic region. Multiple matrix regressions with randomization indicate a link between climate and phenotypic differentiation inferred from leg and pronotum dimensions but not pronotum shape. Niche projections predict severe habitat reduction due to climate warming. Main conclusions: The current distribution and intraspecific diversity of S. piliferus reflect complex biogeographical scenarios consistent with Quaternary climates and volcanism. Phenotypic divergence appears adaptive. Current levels of genetic and phenotypic variation suggest adaptive potential, yet the pace of anthropogenic warming over the next 50 years could result in small populations that may collapse before adapting. Differences in niche features between diverging intraspecific lineages suggest distinct responses to climate change, and this has implications for prioritising conservation actions and management strategies. [ABSTRACT FROM AUTHOR]

Aim: Ongoing climate change is presently influencing the distribution ranges of numerous species, with both range expansions and latitudinal shifts being observed. In southern Europe, a biogeographical border that separates African and European biota, while at the same time acting as a migration bridge for many species, these changes are of particular relevance. This study aimed to analyse the responses of nine typically African birds to climate change to provide information on the ongoing and future occupation of Europe by these species. Location: Western Palearctic and surrounding areas. Methods: To this end, the distributions of the species in their native ranges were modelled, both in the present and in future climate scenarios, using their current breeding ranges and a set of topographic and climatic variables. The climatic favourability for the nine species was then combined using fuzzy logic. Results: The results showed that southern Europe is highly favourable for our set of African birds, except for Rüppell's Vulture, and future forecasts indicated that this favourability would increase further north, again excluding the African Vulture. Main conclusions: If the climate continues to warm, further arrivals of individuals are to be expected, increasing the possibility that self‐sustaining populations may become established in southern Europe. Furthermore, new African species may start to occupy this area, with the likelihood of an Africanisation of the European fauna. Considering the role played by southern Europe as a potential focal point for the colonisation of this continent by African species, it is important to track their northward expansion and future spread. [ABSTRACT FROM AUTHOR]

The rapid acceleration of global warming has led to an increased burden of high temperature-related diseases (HTDs), highlighting the need for advanced evidence-based management strategies. We have developed a conceptual framework aimed at alleviating the global burden of HTDs, grounded in the One Health concept. This framework refines the impact pathway and establishes systematic data-driven models to inform the adoption of evidence-based decision-making, tailored to distinct contexts. We collected extensive national-level data from authoritative public databases for the years 2010e2019. The burdens of five categories of disease causes e cardiovascular diseases, infectious respiratory diseases, injuries, metabolic diseases, and non-infectious respiratory diseases e were designated as intermediate outcome variables. The cumulative burden of these five categories, referred to as the total HTD burden, was the final outcome variable. We evaluated the predictive performance of eight models and subsequently introduced twelve intervention measures, allowing us to explore optimal decision-making strategies and assess their corresponding contributions. Our model selection results demonstrated the superior performance of the Graph Neural Network (GNN) model across various metrics. Utilizing simulations driven by the GNN model, we identified a set of optimal intervention strategies for reducing disease burden, specifically tailored to the seven major regions: East Asia and Pacific, Europe and Central Asia, Latin America and the Caribbean, Middle East and North Africa, North America, South Asia, and Sub-Saharan Africa. Sectoral mitigation and adaptation measures, acting upon our categories of Infrastructure & Community, Ecosystem Resilience, and Health System Capacity, exhibited particularly strong performance for various regions and diseases. Seven out of twelve interventions were included in the optimal intervention package for each region, including raising low-carbon energy use, increasing energy intensity, improving livestock feed, expanding basic health care delivery coverage, enhancing health financing, addressing air pollution, and improving road infrastructure. The outcome of this study is a global decision-making tool, offering a systematic methodology for policymakers to develop targeted intervention strategies to address the increasingly severe challenge of HTDs in the context of global warming. [ABSTRACT FROM AUTHOR]

Aim: We are using the fossil record of different marine plankton groups to determine how their biodiversity has changed during past climate warming comparable to projected future warming. Location: North Atlantic Ocean and adjacent seas. Time series cover a latitudinal range from 75° N to 6° S. Time period: Past 24,000 years, from the Last Glacial Maximum (LGM) to the current warm period covering the last deglaciation. Major taxa studied: Planktonic foraminifera, dinoflagellates and coccolithophores. Methods: We analyse time series of fossil plankton communities using principal component analysis and generalized additive models to estimate the overall trend of temporal compositional change in each plankton group and to identify periods of significant change. We further analyse local biodiversity change by analysing species richness, species gains and losses, and the effective number of species in each sample, and compare alpha diversity to the LGM mean. Results: All plankton groups show remarkably similar trends in the rates and spatio‐temporal dynamics of local biodiversity change and a pronounced non‐linearity with climate change in the current warm period. Assemblages of planktonic foraminifera and dinoflagellates started to change significantly with the onset of global warming around 15,500 to 17,000 years ago and continued to change at the same rate during the current warm period until at least 5000 years ago, while coccolithophore assemblages changed at a constant rate throughout the past 24,000 years, seemingly irrespective of the prevailing temperature change. Main conclusions: Climate change during the transition from the LGM to the current warm period led to a long‐lasting reshuffling of zoo‐ and phytoplankton assemblages, likely associated with the emergence of new ecological interactions and possibly a shift in the dominant drivers of plankton assemblage change from more abiotic‐dominated causes during the last deglaciation to more biotic‐dominated causes with the onset of the Holocene. [ABSTRACT FROM AUTHOR]

Eutrophication is a main threat to continental aquatic ecosystems. Prevention and amelioration actions have been taken under the assumption of a stable climate, which needs reconsideration. Here, we show that reduced precipitation can bring a lake ecosystem to a more productive regime even with a decline in nutrient external load. By analyzing time series of several decades in the largest lake of the Iberian Peninsula, we found autocorrelated changes in the variance of state variables (i.e., chlorophyll and oxygen) indicative of a transient situation towards a new ecosystem regime. Indeed, exceptional planktonic diatom blooms have occurred during the last few years, and the sediment record shows a shift in phytoplankton composition and an increase in nutrient retention. Reduced precipitation almost doubled the water residence time in the lake, enhancing the relevance of internal processes. This study demonstrates that ecological quality targets for aquatic ecosystems must be tailored to the changing climatic conditions for appropriate stewardship. [ABSTRACT FROM AUTHOR]

The Arctic sea ice cover has decreased rapidly over the last few decades both in extent and thickness. Here we present multi‐year (2013–2022) observations of sea ice thickness in the northwestern Barents Sea based on Upward Looking Sonar measurements and show that the winter sea ice has become thicker over the last decade. Sea ice thickness from the Pan‐Arctic Ice Ocean Modeling and Assimilation System (PIOMAS) reproduces both the observed variability and recent 10‐year trend and shows that this thickening (0.24 m decade−1) has not been seen since the 1990s. Using PIOMAS we find that the recent increase in sea ice thickness can be explained by increased sea ice freezing as a result of lower temperatures in the ocean and in the atmosphere. The recent thickening is set in the context of a long‐term thinning trend, with PIOMAS showing much thinner ice now than in the 1980s. Plain Language Summary: The Arctic sea ice cover is becoming smaller and thinner due to global warming. We have measured sea ice thickness in the Barents Sea since 2013, and find that the ice thickness has increased since the measurements were initiated, contrary to what we would expect in a warming world. The Arctic sea ice cover can, however, increase for periods typically up to a decade due to natural climate variability. We find that increased sea ice formation due to lower ocean and air temperatures has caused the recent thickening of the ice cover. We also find that the Barents Sea ice thickness has decreased since the 1980s, and despite the recent thickening, the ice cover is much thinner now than it used to be. Key Points: Upward Looking Sonar measurements in the Barents Sea show increased sea ice thickness during the last decadeIn an ice‐ocean reanalysis (PIOMAS) the recent thickening is due to increased ice freezing, associated with lower ocean and air temperaturesThe long‐term thickness trend is negative, meaning that despite recent thickening, ice is now much thinner than in the 1980s [ABSTRACT FROM AUTHOR]

Previous studies have suggested that global ocean circulation would be significantly changed under global warming, while the change of North Equatorial Countercurrent (NECC) and its mechanisms are still unclear. Here, we investigate the location and intensity changes of NECC under global warming based on CESM1 high‐resolution long‐term simulations from the perspective of the Inter‐Tropical Convergence Zone (ITCZ), considering the close connection between NECC and ITCZ and well‐established changes of ITCZ. It is found that the annual‐mean NECC shifts equatorward of 0.39° and weakens by 21.71% in the RCP8.5 scenario at the end of 21st century. The NECC change is seasonally dependent, with maximum shift and weakening during spring, consistent with the changes of ITCZ. Both the location and intensity changes of ITCZ are important in the NECC changes, especially for spring. The weakening and equatorward shift of ITCZ contributes almost equally to the strongest decrease of spring NECC (47.63%). Plain Language Summary: Global ocean circulation is suggested to exhibit significant changes under global warming, but whether and why the North Equatorial Countercurrent (NECC) would change is still unclear. It is well known that the NECC and Inter‐Tropical Convergence Zone (ITCZ) are closely coupled through air‐sea interaction. Under global warming, previous studies found that the ITCZ would move closer to the equator with maximum shift in spring and the annual‐mean NECC would be weakened in response to the enhanced equatorial warming. Hence, it is important to investigate whether the NECC would change following the ITCZ change. Here, based on long‐term simulations from a high‐resolution climate model, it is found that the NECC will indeed move closer to the equator under global warming following the equatorward shift of ITCZ. The NECC also gets weakened under global warming following the weakened ITCZ convergence, although the ITCZ precipitation gets stronger due to more moisture under warming. In spring, the largest equatorward shift of ITCZ has a comparable contribution to the largest decrease of NECC. Key Points: The North Equatorial Countercurrent (NECC) would be southward shift and weakened under global warmingThe future changes of NECC are seasonally dependent, with maximum southward shift and weakening in springThe NECC changes are closely related to the location and intensity changes of Inter‐Tropical Convergence Zone, especially in spring [ABSTRACT FROM AUTHOR]

Global warming has intensified the intensity of compound drought‐hot extremes (CDHEs), posing more severe impacts on human societies and ecosystems than individual extremes. The vulnerability of global terrestrial ecosystems under CDHEs, along with its key influencing factors, remains poorly understood. Based on multiple remote sensing data, we construct a Vine Copula model to appraise vegetation vulnerability under CDHEs, and attribute it to climatic and biotic factors for five different vegetation types. High vulnerability is detected in central and southern regions of North America, eastern and southern regions of South America, Southern Africa, northern and western Europe, and northern and eastern Australia. The drier the climate, the higher will be the vulnerability. Furthermore, biodiversity and biomass are key biotic factors influencing the vulnerability of various vegetation types, such that ecosystems with richer biodiversity and higher biomass have lower vulnerability to CDHEs. The findings deepen understanding of terrestrial ecosystem response to CDHEs. Plain Language Summary: Drought and hot‐related extremes often coincide or follow one another, known as compound drought‐hot extremes (CDHEs), adversely affecting various vegetation processes. Thus, investigating the response relationship between vegetation dynamics and CDHEs is critical for maintaining the sustainable development of ecosystems under the background of climate warming. High ecosystem vulnerability is detected in central and southern regions of North America, eastern and southern regions of South America, Southern Africa, northern and western Europe, and northern and eastern Australia. Climatic factors (precipitation, arid index, temperature, and radiation) dominate the vulnerability of all vegetation types. The drier the climate, the higher will be the vulnerability of vegetation to CDHEs. Furthermore, biodiversity and biomass are key biotic factors influencing the vulnerability. The results provide us with essential insights for managing and adapting terrestrial ecosystems against climate change and are of interest to a wide range of audiences, including but not limited to ecologists, hydrologists, and climatologists. Key Points: A framework is developed to estimate the vegetation vulnerability in response to compound drought‐hot extremes and attribute it to various factorsVegetation vulnerability is higher for grasses and shrubs than for evergreen and deciduous forestsVegetation vulnerability is both affected by climate and biotic factors, but climate factors are more dominant [ABSTRACT FROM AUTHOR]

Precipitation exhibits a pronounced seasonal cycle, of which the phase and amplitude are closely associated with water resource management. While previous studies suggested an emerged delaying phase in the past decades, whether the amplified amplitude has emerged is controversial. Using multiple observational data sets and climate simulations, here we show that the amplification of precipitation annual cycle has emerged in most global land areas since the 1980s, especially in the tropics. These amplifications are mainly driven by anthropogenic emissions, and will be further intensified by 17.6% in the future (2081–2100) under high emission scenario (Shared Socioeconomic Pathways, SSP585), and limited to 7.2% under SSP126 scenario, relative to the historical period (1982–2014). Precipitation seasonality will be amplified by 4.2% for each 1°C of global warming, which is seen in all emission scenarios. The mitigation of lower emissions is helpful for alleviating the amplification of precipitation seasonality in a warming world. Plain Language Summary: Precipitation displays pronounced seasonal cycle, and its phase and amplitude are closely associated with ecosystems and our society by redistributing water resources. The phase of precipitation cycle has been well understood in previous studies, but how its magnitude changes remain largely unknown. In this study, we use multiple observational data sets and climate simulations to show that precipitation annual cycle has been amplified in most parts of global land area since the 1980s. These amplifications are especially strong in the tropical regions, and are mainly driven by the increases in anthropogenic greenhouse gas and aerosol emissions. In the future (2081–2100) under high emission scenario (SSP585), they will be further intensified by 17.6% relative to the historical period (1982–2014), and will be limited to 7.2% under low emission scenario (SSP126). We also estimate that the amplitude of precipitation seasonality will be increased by around 4.2% for each 1°C of global warming, and suggest that keeping lower emissions is helpful for alleviating the amplification of precipitation seasonality. Key Points: Precipitation annual cycle has been amplified in most global land areas since the 1980s, especially in the tropicsPrecipitation seasonality amplification will be intensified in the future, mainly driven by anthropogenic emissionsThe amplitude of precipitation seasonality will be amplified by ∼4.2% for each 1°C of global warming [ABSTRACT FROM AUTHOR]

All climate models project a weakening of the Atlantic Meridional Overturning Circulation (AMOC) strength in response to greenhouse gas forcing. However, the climate impacts of the AMOC decline alone cannot be isolated from other drivers of climate change using existing Coupled Model Intercomparison Project simulations. To address this issue, we conduct idealized experiments using the EC‐Earth3 climate model. We compare an abrupt 4×CO2 simulation with the same experiment, except we artificially fix the AMOC strength at preindustrial levels. With this design, we can formally attribute differences in climate change impacts between these two experiments to the AMOC decline. In addition, we quantify the state‐dependence of AMOC impacts by comparing the aforementioned experiments with a preindustrial simulation in which we artificially reduce the AMOC strength. Our findings demonstrate that AMOC decline impacts are state‐dependent, thus understanding AMOC impacts on future climate change requires targeted model experiments. Plain Language Summary: Climate models predict that the Atlantic Ocean's major circulation system, known as the Atlantic Meridional Overturning Circulation (AMOC), will weaken during the 21st century. This weakening could have significant impacts on the climate. However, it is challenging to isolate the AMOC's effects because other factors, such as rising greenhouse gas levels, also affect the climate. To better understand the AMOC's role, in this study we use a climate model to conduct numerical experiments. We compare a simulation of the preindustrial climate with one in which we artificially decrease the strength of the AMOC. Then, we compare the preindustrial climate with two forced simulations: one with a fourfold increase in atmospheric carbon dioxide, where the AMOC weakens as expected, and another where we keep the AMOC at its preindustrial strength despite higher CO2 levels. By comparing these experiments, we determine that the impacts of an AMOC decline depend on the background climate state. This research demonstrates that ad‐hoc model experiments are needed to understand the impacts of a weakened AMOC in a changing climate. Key Points: We present new idealized experiments to assess the influence of a weakened Atlantic Meridional Overturning Circulation (AMOC) on future climate changeWe use the EC‐Earth3 climate model to carry out experiments imposing abrupt 4×CO2 forcing but fixing the AMOC strength, and then we compare them with preindustrial water hosing experimentsWe find that AMOC impacts on temperature and precipitation depend on the background climate state [ABSTRACT FROM AUTHOR]

Understanding the impact of various climate forcing agents, such as aerosols, on extreme precipitation is socially and scientifically vital. While anthropogenic absorbing aerosols influence Earth's energy balance and atmospheric convection, their role in extreme events remains unclear. This paper uses convective‐resolving radiative‐convective‐equilibrium simulations, with fixed solar radiation, to investigate the influence of absorbing aerosols on extreme precipitation comprehensively. Our findings reveal an underappreciated mechanism through which absorbing aerosols can, under certain conditions, strongly intensify extreme precipitation. Notably, we demonstrate that a mechanism previously reported for much warmer (hothouse) climates, where intense rainfall alternates with multi‐day dry spells, can operate under current realistic conditions due to absorbing aerosol influence. This mechanism operates when an aerosol perturbation shifts the lower tropospheric radiative heating rate to positive values, generating a strong inhibition layer. Our work highlights an additional potential effect of absorbing aerosols, with implications for climate change mitigation and disaster risk management. Plain Language Summary: Aerosols, particles suspended in the atmosphere, can interact with the incoming solar radiation by scattering or absorbing it. Aerosol species that absorb solar radiation generate local warming of the atmosphere. This local warming changes the vertical profile of temperature and by that affects cloud and precipitation development. In this paper we use idealized computer simulations to investigate the effect of absorbing aerosols on precipitation, and specifically on extreme precipitation events in the tropics. We demonstrate that under certain conditions, absorbing aerosols can strongly enhance extreme precipitation even despite reducing the mean. We show that this trend can be explained by a mechanism previously reported for much warmer climate conditions than currently found on Earth, involving heating by radiation of the lower part of the troposphere. These results have implications for climate change mitigation and disaster risk management. Key Points: The effect of absorbing aerosol on extreme precipitation is examined in idealized convective‐resolving radiative‐convective‐equilibrium simulationsAerosol perturbation that shifts the lower tropospheric radiative heating rate to positive values strongly enhances extreme precipitationThis trend is explained by a mechanism reported before for hothouse climate conditions involving a shift into an "episodic deluge" regime [ABSTRACT FROM AUTHOR]

Current global warming results in an uptake of heat by the Earth system, which is distributed among the different components of the climate system. However, current‐generation climate models deliver heat inventory and partitioning estimates of Earth system components that differ from recent observations. Here we investigate the global heat distribution under warming by using fully‐coupled CMIP6 Earth system model experiments, including a version of the MPI‐ESM with a deep land model component, accommodating the required space for more realistic terrestrial heat storage. The results show that sufficiently deep land models exert increased subsurface land heat uptake, leading to a heat uptake partitioning among the Earth system components that is closer to observational estimates. The results are relevant for the understanding of Earth's heat partitioning and highlight the importance of the land heat sink in the Earth heat inventory. Plain Language Summary: Global warming is associated with heat accumulation in the Earth system due to the intensification of the greenhouse effect. The available heat is distributed unevenly throughout the climate subsystems: the ocean, land, atmosphere, and cryosphere. Overall, the current generation of climate models captures this partitioning well but, on average, shows an overestimation of the ocean heat uptake and an underestimation of the land heat uptake. Previous studies have shown that the lack of heat input into the land comes from structural limitations in the land model components used. In this study, we account for these shortcomings, which greatly improve the land heat uptake in simulations of future climate scenarios. We find that, as a result, the fraction of simulated heat taken up by the ocean is reduced. This leads to a heat distribution among the climate subsystems that is closer to observational estimates. Our results highlight that land heat uptake is relevant for the Earth system heat distribution and that future research should consider modeling approaches including a more realistic land heat sink. Key Points: Considering a sufficient land depth in current‐generation Earth system models facilitates realistic land heat uptake estimates under warmingIncreased land heat uptake leads to an adjusted global heat distribution and a reduced overestimation of simulated ocean heat uptakeThe land heat sink is relevant for the projection of the global energy inventory and its partitioning under global warming [ABSTRACT FROM AUTHOR]

Existing studies have shown changes in the impact of atmospheric teleconnections on Indian Summer Monsoon (ISM) at interannual time scales due to the changing background state. However, the exploration of potential changes at subseasonal time scales remains limited. In this study, we use a causal discovery method to find the tropical atmospheric drivers of ISM subseasonal anomalies, and quantify the causal effects of the drivers on ISM, as well as the changes in causal effects over the past 40 years. We find the impact of tropical western Pacific on ISM subseasonal anomalies has strengthened, while the ISM self‐feedback has weakened. Wavenumber‐frequency analysis shows that the Rossby wave energy over 15°N–30°N at periods of 10–20 days has increased over the past four decades, which offers a plausible explanation for the enhanced tropical atmospheric teleconnection between western Pacific and ISM at subseasonal time scales. Plain Language Summary: The subseasonal variability of Indian Summer Monsoon (ISM) is vital to agriculture and economy. Therefore, it is important to understand the drivers of ISM subseasonal anomalies, how strong an impact of a driver is, as well as potential changes in the strength of such an impact. In this study, we explore the possible drivers for ISM subseasonal anomalies by using a causal discovery method, and taking into account the tropical geopotential height anomalies together with the ISM. Two tropical atmospheric drivers of ISM subseasonal anomalies are detected: one is the geopotential height anomalies over the tropical western Pacific, and the other is the ISM itself. Over the past four decades, the tropical western Pacific has exerted an enhanced influence on ISM subseasonal anomalies, while the self‐feedback of ISM has weakened. Under global warming, more anomalous convection signals can emanate over the western Pacific, and propagate westward to influence the ISM region, which might explain the physical mechanism behind the enhanced impact of the western Pacific on ISM subseasonal anomalies. Key Points: Causal analysis reveals the causal impact of the tropical western Pacific on Indian Summer Monsoon (ISM) and of ISM on itself at subseasonal time scalesThe causal impact of the western Pacific on ISM has strengthened, while the ISM self‐feedback has weakened over the past 40 yearsThe impact of the tropical western Pacific on ISM subseasonal anomalies is strengthening due to amplified Rossby wave energy over 15°N–30°N [ABSTRACT FROM AUTHOR]

The cloud feedback may result in amplification or damping of Arctic warming. Two common techniques used to diagnose the top‐of‐the‐atmosphere cloud feedback are the Adjusted Cloud Radiative Effect (AdjCRE) method and the Cloud Radiative Kernel (CRK) method. We apply both to CMIP5 and CMIP6 model data, finding that the AdjCRE calculated Arctic shortwave cloud feedback is twice as correlated with sea ice loss in CMIP5, and four times in CMIP6, as the CRK method. We find that the CRK method produces Arctic all‐sky residual percentages exceeding 20% in 15 of 18 models. We use the CRK method to decompose the feedback in CMIP5 and CMIP6 finding that its median value changed from negative to positive driven by a less‐negative cloud optical depth feedback. Despite its lack of closure, we conclude that the CRK method is better suited for Arctic SW feedbacks as it is less impacted by surface albedo changes. Plain Language Summary: The cloud feedback is the process by which cloud property changes in a warming climate can either further enhance warming or damp it. The Arctic is warming faster than the rest of the globe, and one of the largest sources of uncertainty in its climate projections is the cloud feedback. There are two popular methods to calculate the cloud feedback: the Adjusted Cloud Radiative Effect technique, and the Cloud Radiative Kernel technique. In this paper we compare the two methods in a suite of climate models by considering the extent to which changes in Arctic sea ice impact the cloud feedbacks. From this analysis we conclude that the Cloud Radiative Kernel method is less affected by sea ice loss. We then apply the Cloud Radiative Kernel technique to data from the two most recent generations of global climate models to investigate how polar day Arctic cloud feedbacks have changed between these generations. We find that the median value of these Arctic feedbacks is slightly positive in the newest generation of models, a change from slightly negative in the previous generation that is largely fueled by a weakening of the feedback associated with changes in cloud optical depth. Key Points: The Cloud Radiative Kernel method is less sensitive to surface albedo changes than the Adjusted Cloud Radiative Effect techniqueThe Cloud Radiative Kernel method provides poor radiative closure in a suite of global climate modelsThe median shortwave Arctic cloud feedback in recent climate models is slightly positive due to a weakened cloud optical depth feedback [ABSTRACT FROM AUTHOR]

Documenting the seasonal temperature cycle constitutes an essential step toward mitigating risks associated with extreme weather events in a future warmer world. The mid-Piacenzian Warm Period (mPWP), 3.3 to 3.0 million years ago, featured global temperatures approximately 3°C above preindustrial levels. It represents an ideal period for directed paleoclimate reconstructions equivalent to model projections for 2100 under moderate Shared Socioeconomic Pathway SSP2-4.5. Here, seasonal clumped isotope analyses of fossil mollusk shells from the North Sea are presented to test Pliocene Model Intercomparison Project 2 outcomes. Joint data and model evidence reveals enhanced summer warming (+4.3° ± 1.0°C) compared to winter (+2.5° ± 1.5°C) during the mPWP, equivalent to SSP2-4.5 outcomes for future climate. We show that Arctic amplification of global warming weakens mid-latitude summer circulation while intensifying seasonal contrast in temperature and precipitation, leading to an increased risk of summer heat waves and other extreme weather events in Europe's future. [ABSTRACT FROM AUTHOR]

The Intertropical Convergence Zone (ITCZ) has an annual mean location north of the equator today. The factors determining this location and the evolution to its modern state are actively debated. Here we investigate how the Atlantic Meridional Overturning Circulation (AMOC) influences the ITCZ during the early‐to‐middle Miocene. By conducting a sensitivity study with an open Canadian Arctic Archipelago gateway, we show that North Atlantic Deep‐Water formation strengthens the AMOC, in alignment with Miocene North Atlantic ventilation proxies. A vigorous AMOC increases northward Atlantic Ocean heat transport and cross‐equatorial atmospheric energy transport shifts southwards to compensate, pushing the ITCZ northwards. Our study supports AMOC development as a strong contributor to the ITCZ's northern location today. Existing proxy‐based interpretations of ITCZ history are too sparse to strongly confirm these results. We predict a strong in‐phase relationship between AMOC strength and ITCZ's northward location, which should be testable in high resolution paleoclimate records. Plain Language Summary: The Intertropical Convergence Zone (ITCZ) is a narrow tropical region where tropical rainfall is concentrated. Its annual mean position is predominantly north of the equator in the modern climate, especially in the Atlantic and eastern Pacific oceans. The position of the ITCZ varies seasonally and over long‐time scales. One hypothesis is that Atlantic Meridional Overturning Circulation (AMOC) energy transport displaces the ITCZ north of the Equator. We test this hypothesis in a paleoclimate simulation with realistic early‐to‐middle Miocene (20–11.6 million years ago) configurations. By opening the Canadian Arctic Archipelago gateway, a crucial connection between the Arctic Ocean and North Atlantic, we find that a strong AMOC transports more heat northward in the ocean, and in compensation, the flow of atmospheric energy across the equator shifts southward, consequently pushing the ITCZ north of the equator. More Miocene proxy records are required to empirically support this model result. Key Points: Opening an Arctic Ocean gateway in Miocene climate simulations generates a strong Atlantic Meridional Overturning Circulation (AMOC) and increases northward ocean heat transportTo compensate, atmospheric energy transport across the equator shifts southward, pushing the Intertropical Convergence Zone (ITCZ) north of the equatorAMOC strengthening is a mechanism in past warm climates for northward ITCZ shifts [ABSTRACT FROM AUTHOR]