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The current climate crisis and related extreme weather phenomena massively influence everyday human life and thus also armed conflict and peace. Acknowledging the human origin of these biospheric instabilities introduces the geological era of the Anthropocene. While it is built around the acknowledgment of the human ability to indelibly alter Earth's physis, it does not celebrate humanity's sovereignty, but rather indicates the dissolution of agency within the complex interrelationships between the human and the nonhuman world. The Anthropocene and the issue of peace obviously interrelate. This essay describes the Anthropocene not only as a useful conception in approaching peace, but as its conditio sine qua non. Its ontological implications highlight the substantial share of nonhuman agency and complexity through extreme weather phenomena in armed conflict and peace, while its epistemological innovations reveal the indispensability of the dissolution of the modernist transcendental ego for reasoning about and practicing peace. Peace in the Anthropocene means to let the world and its myriads of human and nonhuman inhabitants speak and to take them seriously. [ABSTRACT FROM AUTHOR]

Arctic sea-ice loss is a consequence of anthropogenic global warming and can itself be a driver of climate change in the Arctic and at lower latitudes, with sea-ice minima likely favoring extreme events over Europe and North America. Yet the role that the sea-ice plays in ongoing climate change remains uncertain, partly due to a limited understanding of whether and how the exact geographical distribution of sea-ice loss impacts climate. Here we demonstrate that the climate response to sea-ice loss can vary widely depending on the pattern of sea-ice change, and show that this is due to the presence of an atmospheric feedback mechanism that amplifies the local and remote signals when broader scale sea-ice loss occurs. Our study thus highlights the need to better constrain the spatial pattern of future sea-ice when assessing its impacts on the climate in the Arctic and beyond. [ABSTRACT FROM AUTHOR]

Understanding the Anthropocene—as both a set of physiological phenomena and as an existential crisis of modernity—requires interrogating Earth-changing transformations in food and agriculture. Agri-food systems are not only at the core of alarming environmental trends; they also offer opportunities to directly engage important challenges to the Anthropocene concept. Many human geographers and other social scientists have raised critiques of the Anthropocene designation as glossing over social inequities, codifying a separation of humans from their environments, and naturalizing current transformations as complete and irreversible. In this article we interrogate the intersection between agri-food studies and critical Anthropocene scholarship, arguing that agri-food systems serve as a through line to competing Anthropocene origin stories, a source of theoretical insight for the complexity of human–environment relations, and a site of agency for engaging alternative futures. First, we examine four of the most commonly proposed starting points for the Anthropocene epoch, arguing that a focus on food and agriculture at each historical moment reveals the limits, frictions, and social unevenness of anthropogenic change. Second, we highlight theoretical tools from critical agrarian studies that help build a more complex understanding of agriculture and the Anthropocene, emphasizing the active role of agroecosystems and the centrality of structural inequalities to agroenvironmental change. Finally, we examine how food- and agriculture-related social movements are working to forge more livable futures by accounting for precisely the matters that characterizations of the Anthropocene as an epoch of global human dominance frequently overlook: socioecological unity and political economic difference. [ABSTRACT FROM AUTHOR]

Using lightning flash data from the National Lightning Detection Network with an updated lightning nitrogen oxides (NOx) emission estimation algorithm in the Community Multiscale Air Quality (CMAQ) model, we estimate the hourly variations in lightning NOx emissions for the summer of 2011 and simulate its impact on distributions of tropospheric ozone (O3) across the continental United States. We find that typical summer-time lightning activity across the U.S. Mountain West States (MWS) injects NOx emissions comparable to those from anthropogenic sources into the troposphere over the region. Comparison of two model simulation cases with and without lightning NOx emissions show that significant amount of ground-level O3 in the MWS during the summer can be attributed to the lightning NOX emissions. The simulated surface-level O3 from a model configuration incorporating lightning NOx emissions showed better agreement with the observed values than the model configuration without lightning NOx emissions. The time periods of significant reduction in bias in simulated O3 between these two cases strongly correlate with the time periods when lightning activity occurred in the region. The inclusion of lightning NOx increased daily maximum 8 h O3 by up to 17 ppb and improved model performance relative to measured surface O3 mixing ratios in the MWS region. Analysis of model results in conjunction with lidar measurements at Boulder, Colorado during July 2014 corroborated similar impacts of lightning NOx emissions on O3 air quality. The magnitude of lightning NOx emissions estimated for other summers is comparable to the 2011 estimates suggesting that summertime surface-level O3 levels in the MWS region could be significantly influenced by lightning NOx. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the contribution of anthropogenic climate change to the likelihood of an extreme summer heat wave, like the summer 2017 in western Europe and Euro-Mediterranean. It explores the return period and changing risk of heat waves as well as looks at the 3-day-mean area-averaged daily maximum temperatures. The trends in the likelihood of 3-day heat waves are noted.

The article presents a study which examines the anthropogenic contributions to the extreme rainfall of March 2017 in Peru. Data and methods used in the study are described, including the climatological thresholds, average rainfall, and probabilistic event attribution methodology. The increase in the likelihood of extremes due to the coastal El Niño is explored.

The article presents a study which examines the potential contributions of anthropogenic warming of Western V sea surface temperatures to the 2017 East African drought. It explores the climate trends in East African region, including rainfall anomalies, sea surface temperature, and precipitation attribution. The production of warm Western V sea surface temperature of drying on decadal and seasonal timescales is suggested.

The article presents a study which examines the contribution of anthropogenic climate change to the risk of the April-May 2017 extreme precipitation in the Uruguay River basin, which resulted to extensive flood and major socioeconomic impacts. Data and methods used in the study are described, including anomalous precipitation, Climate Prediction Center's Global Unified Precipitation data, and sea surface temperature and sea ice coverage.

The article presents a study which examines the contributions of anthropogenic warming and El Niño-Southern Oscillation (ENSO) on record low sunshine over Japan during August 2017. It suggests that the persistent cold inflow along the anomalous cyclone over Japan, simultaneously induced by extraordinary development of the Okhotsk high, attributed to the prolonged low sunshine. The link of anthropogenic warming to increased probability of extremely enhanced anticyclones is noted.

The article presents a study which examines the link of the lowest sea-ice extent on record with the lowest precipitation event over parts of western Europe, and the anthropogenic contribution to the climate change. Data and methods used in the study are described, including sea ice concentration, European precipitation, and sea level pressure. Three sets of retrospective forecasts to attribute the reduced Arctic sea ice conditions with the lowest European precipitation event are noted.

The article presents a study which examines anthropogenic contribution to the May 2017 extreme heat and the earliest summer onset in South Korea. Data and methods used in the study are noted, including daily mean temperatures, regional climate model, and global climate model. An analysis of the risk ratio and fraction of attributable risk to assess changes in the probabilities of occurrence of extreme summer onset is offered.

The article presents a study which explores the role of anthropogenic warming in increasing the likelihood of heat waves, like the 5-day July 2017 event in central eastern China. Data and methods used for the study are noted, including observations of daily maximum temperatures (Tmax), sea surface temperature (SST), and risk ratio and attributable risks. Results suggest that anthropogenic warming increases the risk of rarer, more extreme heat waves.

Purpose: Febrile seizure (FS) is the most common type of seizure in children between 6 months to 5 years of age. A family history of febrile seizures can increase the risk a child will have a FS. Yet, prevalence of FS regarding external environment has not been clearly proved. This study attempts to determine the association between prevalence of FS and weather. Methods: This study included medical records from the Korea National Health Insurance Review and Assessment Service. Data were collected from 29,240 children, born after 2004, diagnosed with FS who were admitted to one of the hospitals in Seoul, Korea, between January 2009 and December 2013. During the corresponding time period, data from the Korea Meteorological Administration on daily monitoring of four meteorological factors (sea-level pressure, amount of precipitation, humidity and temperature) were collected. The relationships of FS prevalence and each meteorological factor will be designed using Poisson generalized additive model (GAM). Also, the contributory effect of viral infections on FS prevalence and weather will be discussed. Results: The amount of precipitation was divided into two groups for comparison: one with less than 5 mm and the other with equal to or more than 5 mm. As a result of Poisson GAM, higher prevalence of FS showed a correlation with smaller amount of precipitation. Smoothing function was used to classify the relationships between three variables (sea-level pressure, humidity, and temperature) and prevalence of FS. FS prevalence was correlated with lower sea-level pressure and lower humidity. FS prevalence was high in two temperature ranges (-7 to -1℃ and 18-21℃). Conclusion: Low sea-level pressure, small amount of precipitation, and low relative air humidity may increase FS prevalence risk. [ABSTRACT FROM AUTHOR]

Observations show that the East Asian winter monsoon (EAWM) experienced an interdecadal weakening in the mid-1980s. This is evident for all members of the EAWM system (i.e., East Asian trough, upper-tropospheric jet stream, and lower-tropospheric monsoon circulation). Here, we investigate the relative contributions of natural (volcanic aerosols and solar variability) and anthropogenic [greenhouse gases (GHGs) and anthropogenic aerosols] forcings to this interdecadal weakening using multiple coupled models within phase 5 of the Coupled Model Intercomparison Project (CMIP5). The results indicate that in the midtroposphere, the increased GHG concentrations play an important role in weakening the East Asian trough (EAT) by increasing the sea surface temperatures (SSTs) over the North Pacific. In the upper troposphere, natural external forcings contribute to the observed weakening of the meridional shear of the East Asian jet stream (EAJS) by regulating the meridional temperature gradient (MTG) over the East Asian region. In the lower troposphere, both anthropogenic and natural forcings can weaken the Siberian high during this period. Overall, based on the present analysis of the CMIP5 output, GHGs and natural forcings play key roles in shaping the observed interdecadal weakening of the EAWM during the mid-1980s. Additionally, contributions from internal variability cannot be neglected and require further investigation. [ABSTRACT FROM AUTHOR]

Long-standing wastewater and reclaimed water irrigation systems degrade groundwater quality and thus pose great risks to local soils and even to human health. In this study, seasonal variations in hydrochemical characteristics of groundwater were assessed to determine possible processes that induce groundwater degradation. Beijing was used as the focus area. A total of 82 wells at the southeast irrigation region of Beijing were investigated in 2014. Descriptive statistics, correlation analysis, Piper diagram, and saturation indices were used to distinguish seasonal variations in hydrochemistry in shallow and deep groundwater and possible reclaimed water irrigation effects. The main natural controlling processes include mineral precipitation and dissolution, cation exchange reactions, and dilution effects in shallow and deep groundwater. However, cation exchange reactions are considered to be intense in deeper aquifer. Additionally, shallow groundwater sites subjected to salinization and nitrate contamination were associated with intensive agricultural input and reclaimed water leaching. Sites continuously contaminated by nitrate were mainly distributed on highly permeable sediments. Irrigation with deep groundwater may reduce soil drainage conditions due to a high percentage of sodium. Overall, seasonal replenishment for subterranean quaternary aquifers from rainfall or irrigation plays a vital role in seasonal variation in shallow groundwater hydrochemistry. [ABSTRACT FROM AUTHOR]

The article talks about impacts of climate change on the ongoing extreme weather conditions along with research work done in association to this. Topics addressed include details on publishing of American Meteorological Society bulletin on annual collection of studies measuring the impact of climate change on extreme weather events in 2017 and role of anthropogenic effects on risk of a severe heat wave.

Since the degradation of the marine environment is strongly linked to human activities, having citizens who appreciate the ocean's influence on them and their influence on the ocean is important. Research has shown that citizens have a limited understanding of the ocean and it is this lack of ocean literacy that needs to change. This study maps the European landscape of barriers to teaching 12–19 year olds about the ocean, through the application of Collective Intelligence, a facilitation and problem solving methodology. The paper presents a meta-analysis of the 657 barriers to teaching about the ocean, highlighting how these barriers are interconnected and influence one another in a European Influence Map. The influence map shows 8 themes: Awareness and Perceived knowledge; Policies and Strategies; Engagement, formal education sector; the Ocean itself; Collaboration; Connections between humans and the ocean and the Blue Economy, having the greatest influence and impact on marine education. “Awareness and Perceived knowledge” in Stage 1, exerts the highest level of overall influence in teaching 12–19 year olds about the ocean. This map and study serves as a roadmap for policy makers to implement mobilisation actions that could mitigate the barriers to teaching about the ocean. Examples of such actions include free marine education learning resources such as e-books, virtual laboratories or hands-on experiments. Thus, supporting educators in taking on the challenge of helping our youth realise that the ocean supports life on Earth is essential for education, the marine and human well-being. [ABSTRACT FROM AUTHOR]

The uncertainty of global summer precipitation simulated by the 23 CMIP5 CGCMs and the possible impacts of model resolutions are investigated in this study. Large uncertainties exist over the tropical and subtropical regions, which can be mainly attributed to convective precipitation simulation. High-resolution models (HRMs) and lowresolution models (LRMs) are further investigated to demonstrate their different contributions to the uncertainties of the ensemble mean. It shows that the high-resolution model ensemble means (HMME) and low-resolution model ensemble mean (LMME) mitigate the biases between the MME and observation over most continents and oceans, respectively. The HMME simulates more precipitation than the LMME over most oceans, but less precipitation over some continents. The dominant precipitation category in the HRMs (LRMs) is the heavy precipitation (moderate precipitation) over the tropic regions. The combinations of convective and stratiform precipitation are also quite different: the HMME has much higher ratio of stratiform precipitation while the LMME has more convective precipitation. Finally, differences in precipitation between the HMME and LMME can be traced to their differences in the SSTsimulations via the local and remote airsea interaction. [ABSTRACT FROM AUTHOR]

Factors responsible for extreme monthly rainfall over Texas and Oklahoma during May 2015 are assessed. The event had a return period of at least 400 years, in contrast to the prior record, which was roughly a 100-yr event. The event challenges attribution science to disentangle factors because it occurred during a strong El Niño, a natural pattern of variability that affects the region's springtime rains, and during the warmest global mean temperatures since 1880. Effects of each factor are diagnosed, as is the interplay between El Niño dynamics and human-induced climate change. Analysis of historical climate simulations reveals that El Niño was a necessary condition for monthly rains to occur having the severity of May 2015. The model results herein further reveal that a 2015 magnitude event, whether conditioned on El Niño or not, was made neither more intense nor more likely to be due to humaninduced climate change over the past century. The intensity of extreme May rainfall over Texas and Oklahoma, analogous to the 2015 event, increases by roughly 5% by the latter half of the twenty-first century. No material changes occur in either El Niño-related teleconnections or in overall atmospheric dynamics during extreme May rainfall over the twenty-first century. The increased severity of Texas/Oklahoma May rainfall events in the future is principally due to thermodynamic driving, although much less than implied by simple Clausius-Clapeyron scaling arguments given a projected 23% increase in atmospheric precipitable water vapor. Other thermodynamic factors are identified that act in opposition to the increase in atmospheric water vapor, thereby reducing the effectiveness of overall thermodynamic driving of extreme May rainfall changes over Texas and Oklahoma. [ABSTRACT FROM AUTHOR]

Two large ensembles (LEs) of historical climate simulations are used to compare how various statistical methods estimate the sea surface temperature (SST) changes due to anthropogenic and other external forcing, and how their removal affects the internally generated Atlantic multidecadal oscillation (AMO), Pacific decadal oscillation (PDO), and the SST footprint of the Atlantic meridional overturning circulation (AMOC). Removing the forced SST signal by subtracting the global mean SST (GM) or a linear regression on it (REGR) leads to large errors in the Pacific. Multidimensional ensemble empirical mode decomposition (MEEMD) and quadratic detrending only efficiently remove the forced SST signal in one LE, and cannot separate the short-term response to volcanic eruptions from natural SST variations. Removing a linear trend works poorly. Two methods based on linear inverse modeling (LIM), one where the leading LIM mode represents the forced signal and another using an optimal perturbation filter (LIMopt), perform consistently well. However, the first two LIM modes are sometimes needed to represent the forced signal, so the more robust LIMopt is recommended. In both LEs, the natural AMO variability seems largely driven by the AMOC in the subpolar North Atlantic, but not in the subtropics and tropics, and the scatter in the AMOC-AMO correlation is large between individual ensemble members. In three observational SST reconstructions for 1900-2015, linear and quadratic detrending, MEEMD, and GM yield somewhat different AMO behavior, and REGR yields smaller PDO amplitudes. Based on LIMopt, only about 30% of the AMO variability is internally generated, as opposed to more than 90% for the PDO. The natural SST variability contribution to global warming hiatus is discussed. [ABSTRACT FROM AUTHOR]

Fine-scale genetic structure (FSGS) is common in plants, driven by several ecological and evolutionary processes, among which is gene flow. Mangrove trees rely on ocean surface currents to spread their hydrochorous propagules through space. Since pollen dispersal is generally restricted to local scales, high level of short-distance propagule dispersal is expected to result in FSGS in Rhizophora spp. We investigated FSGS, recent bottleneck events, as well as historical and contemporary expansion patterns in Rhizophora racemosa populations from the entire coast of Cameroon, using 11 polymorphic microsatellite markers. Populations of the Cameroon Estuary complex (CEC) showed significant FSGS and significant reduction in effective population sizes (recent bottlenecks), compared to the other areas. Additionally, our results indicate stark differences between historical and contemporary expansion models. These suggest that contemporary processes such as restricted propagule dispersal, bottleneck events from high indirect and direct anthropogenic pressure, and recolonization by founders from ancient local pockets/refugia most plausibly shape the patterns of FSGS in the CEC. [ABSTRACT FROM AUTHOR]

Using the Nationwide Inpatient Sample and US weather data, we estimated the probability of community-acquired pneumonia (CAP) being diagnosed as Legionnaires' disease (LD). LD risk increases when weather is warm and humid. With warm weather, we found a dose-response relationship between relative humidity and the odds for LD. When the mean temperature was 60°-80°F with high humidity (>80.0%), the odds for CAP being diagnosed with LD were 3.1 times higher than with lower levels of humidity (<50.0%). Thus, in some regions (e.g., the Southwest), LD is rarely the cause of hospitalizations. In other regions and seasons (e.g., the mid-Atlantic in summer), LD is much more common. Thus, suspicion for LD should increase when weather is warm and humid. However, when weather is cold, dry, or extremely hot, empirically treating all CAP patients for LD might contribute to excessive antimicrobial drug use at a population level. [ABSTRACT FROM AUTHOR]

In this study, the characteristics of precipitation in terms of various nitrogen forms (NO 3 − , NO 2 − , NH 4 + , N organic , N total ) is presented. The samples were collected in the areas of different anthropogenic pressure (urban area vs. ecologically protected woodland area, ∼30 km distant from each other; Wielkopolska region, Poland). Based on the N ox and N red emission profiles (N ox /N red ratio), temporal and spatial comparison was carried out. For both sites, during a decade of observation, more than 60% of samples had higher contribution of N-NH 4 + than N-NO 3 - , the amount of N-NO 2 - was negligible, and organic nitrogen amounted to 30% of total nitrogen content which varied up to 16 mg/l. The precipitation events w ith high concentration of nitrogen species were investigated in terms of possible local and remote sources of nitrogen (synoptic meteorology), to indicate the areas which can act as potential sources of N-compounds. Based on the chemometric analysis, it was found that N red implies N ox and vice versa, due to interactions between them in the atmosphere. Taking into account the analysis of precipitation occurring simultaneously in both locations (about 50% of all rainfall episodes), it was observed that such factor as anthropogenic pressure differentiates but does not determine the chemical composition of precipitation in the investigated areas (urban vs. woodland area; distance of ∼30 km). Thermodynamics of the atmosphere had a significant impact on concentrations of N-NO 3 - and N-NH 4 + in precipitation, as well as the circulation of air masses and remote N sources responsible for transboundary inflow of pollutants. [ABSTRACT FROM AUTHOR]

It is becoming popular to use biometeorological indexes to study the effects of weather on human health. Most of the biometeorological indexes were developed decades ago and only applicable to certain locations because of different climate types. Merely using standard biometeorological indexes to replace typical weather factors in biometeorological studies of different locations may not be an ideal research direction. This research is aimed at assessing the difference of statistical power between using standard biometeorological indexes and typical weather factors on describing the effects of extreme weather conditions on daily ambulance demands in Hong Kong. Results showed that net effective temperature and apparent temperature did not perform better than typical weather factors in describing daily ambulance demands in this study. The maximum adj- R improvement was only 0.08, whereas the maximum adj- R deterioration was 0.07. In this study, biometeorological indexes did not perform better than typical weather factors, possibly due to the differences of built environments and lifestyles in different locations and eras. Regarding built environments, the original parameters for calculating the index values may not be applicable to Hong Kong as buildings in Hong Kong are extremely dense and most are equipped with air conditioners. Regarding lifestyles, the parameters, which were set decades ago, may be outdated and not suitable to modern lifestyles as using hand-held electrical fans on the street to help reduce heat stress are popular. Hence, it is ideal to have tailor-made updated location-specific biometeorological indexes to study the effects of weather on human health. [ABSTRACT FROM AUTHOR]

Distribution of Sea of Azov water on the Crimean shelf and its penetration into the Gulf of Feodosia result in significant changes in the hydrophysical and hydrochemical structure of the water area. This inflow is also estimated as a major source of anthropogenic pollution in the region. At the same time, the Gulf of Feodosia is one of the least investigated areas of Russian Black Sea coast. The paper focuses on the hydrophysical structure of the Gulf of Feodosia and southeastern part of the Crimean shelf. The results of a field survey in May 2015 made it possible to reveal the presence of Sea of Azov water in the gulf and describe its thermohaline properties, along with the character of distribution. It is shown that contamination of Sea of Azov water in the gulf could mostly be determined by the synoptic dynamic processes in the area rather than by the seasonal variability of discharge in the Kerch Strait. The possible influence of the distribution of Sea of Azov water on the formation of cyclonic gyres in the coastal area of the region is indirectly confirmed by in situ measurements. [ABSTRACT FROM AUTHOR]

The Sr isotope composition ( 87 Sr/ 86 Sr) and Sr content of waters of the Warta River (central-western Poland) and its tributaries were used to fingerprint water sources and their interactions in space and time. Dissolved Sr in river water of the Warta is characterized by a relatively narrow range of the 87 Sr/ 86 Sr values, from 0.7090 to 0.7105, which contrasts with a strong variation in isotopic signatures of the tributaries, from 0.7080 to 0.7121. With the exception of three streams, which include inputs of mine waters, the waters of tributaries are more enriched in 87 Sr than the master stream. The overall Sr budget of the Warta watershed is determined by the relative contributions of carbonate dissolution and silicate weathering. It can be accounted for by mixing between waters from three reservoirs: 1) groundwater charged with Sr through interaction with Sr-bearing clay minerals, 2) groundwater related to weathering (dissolution) of carbonate rocks, and 3) atmospheric waters charged with Sr from the near-surface weathering and wash-out of Quaternary glaciogenic deposits. Superimposed on the natural Sr isotope systematics is impact of mine waters and fertilizers. The former providing non-radiogenic Sr from the Permian/Mesozoic aquifers constitutes an important anthropogenic element of the Sr budget, whereas the impact of the latter is presumably common but of minor importance. The present-day Sr isotope systematics of the Warta is temporary and different from that of the pre-industrial times. [ABSTRACT FROM AUTHOR]

The human dimensions of visibility degradation remain under-researched academically. Based on Zube and Sell'sProcess Model of the Perception of, and Response to, Environmental Change, a questionnaire survey was conducted in Hong Kong between 5 June 2012 and 26 January 2013 (n= 1,203). The respondents’ perceptions towards visibility degradation were collected. The results show that respondents were moderately knowledgeable to visibility degradation, perceiving the problem as anthropogenic and unfavorable and identifying the fight against the degradation as an important environmental issue. It is further deduced that the respondents’ physical and sociocultural attributes, and the way they gain information about visibility degradation, can affect their perceptions of visibility degradation. The results reveal that improving information channels can positively promote human sensitivity to and understanding of visibility degradation in order to mitigate it. Yet, any attempts to educate the lay public should not assume the existence of a homogenous community of like-minded people. [ABSTRACT FROM PUBLISHER]

Much of the uncertainty in estimates of the anthropogenic forcing of climate change comes from uncertainties in the instantaneous effect of aerosols on cloud albedo, known as the Twomey effect or the radiative forcing from aerosol–cloud interactions (RFaci), a component of the total or effective radiative forcing. Because aerosols serving as cloud condensation nuclei can have a strong influence on the cloud droplet number concentration (Nd), previous studies have used the sensitivity of the Nd to aerosol properties as a constraint on the strength of the RFaci. However, recent studies have suggested that relationships between aerosol and cloud properties in the present-day climate may not be suitable for determining the sensitivity of the Nd to anthropogenic aerosol perturbations. Using an ensemble of global aerosol–climate models, this study demonstrates how joint histograms between Nd and aerosol properties can account for many of the issues raised by previous studies. It shows that if the anthropogenic contribution to the aerosol is known, the RFaci can be diagnosed to within 20% of its actual value. The accuracy of different aerosol proxies for diagnosing the RFaci is investigated, confirming that using the aerosol optical depth significantly underestimates the strength of the aerosol–cloud interactions in satellite data. [ABSTRACT FROM AUTHOR]

Different components of global change (e.g., climate change, land use, pollution, and introduced species) continue to alter biodiversity worldwide. As northern regions are still relatively undisturbed and will likely face clear increases in temperature in the near-future, we examined the signs of biodiversity change due to anthropogenic stressors using a systematic review of previous studies. Our aim was to map where, in which way, and owing to which stressor biodiversity in northern regions has changed. We made a systematic literature search covering the years between 2000 and 2015 to obtain a comprehensive selection of recent research. As species richness was clearly the most commonly used indicator of biodiversity, we only concentrated on this aspect of biodiversity. We compared different biological groups, regions, and ecosystems. In the majority of the cases, anthropogenic stressors had decreased species richness, or had no effects on it, while increasing or multiple effects of stressors on species richness were less common. Freshwater ecosystems were most sensitive to anthropogenic stressors, as species richness often decreased owing to these stressors. The effects of land use on richness were covered relatively widely in the selected set of articles, but the effects of other components of global change on species richness require further attention. Despite the fact that pollution was not as commonly studied stressor as land use, it was the most harmful stressor type affecting species richness. Geographically, most studies were located in boreal Canada or Fennoscandia, while no studies were executed in vast circumpolar areas where the temperature rise has been greatest and the projected climate change is likely to be fast. Overall, we could find an alarmingly small set of studies that described the effects of actual anthropogenic stressors in real-life circumstances in northern high latitudes. [ABSTRACT FROM AUTHOR]

Available proxy-based temperature reconstructions covering the past millennium display contrasted evolutions between the continents. The difference is particularly large between the two hemispheres. When driven by realistic natural and anthropogenic forcings, climate models tend to simulate a more spatially homogenous temperature response. This is associated with a relatively good agreement between model results and reconstructions in the Northern Hemisphere but a low consistency in the Southern Hemisphere. Here, simulations with data assimilations are performed to analyse the causes of this apparent disagreement. It shows that, when the uncertainties are taken into account, states of the climate system compatible with the forcing estimates, the reconstructions and the model physics can be obtained over the past millennium, except for the twentieth century in Antarctica where the simulated warming is always much larger than in the reconstructions. Such states consistent with all sources of information can be achieved even if the uncertainties of the reconstructions are underestimated. Although, well within the range of the proxy-based reconstructions, the temperatures obtained after data assimilation display more similar developments between the hemispheres than in those reconstructions. Ensuring the compatibility does not require to systematically reduce the model response to the forcing or to strongly enhance the model internal variability. From those results, there is thus no reason to suspect that the model is strongly biased in one aspect or another. The constraint imposed by the data assimilation is too low to unambiguously identify the origin of each feature displayed in the reconstructions but, as expected, changes in atmospheric circulation likely played a role in many of them. Furthermore, ocean heat uptake and release as well as oceanic heat transport are key elements to understand the delayed response of the Southern Hemisphere compared to the northern one during some transitions from warmer to colder states or from colder to warmer ones. The last millennium is thus an interesting test period to better understand and quantify the associated mechanisms. [ABSTRACT FROM AUTHOR]

Analysis of observations indicates that there was a rapid increase in summer (June-August) mean surface air temperature (SAT) since the mid-1990s over Western Europe. Accompanying this rapid warming are significant increases in summer mean daily maximum temperature, daily minimum temperature, annual hottest day temperature and warmest night temperature, and an increase in frequency of summer days and tropical nights, while the change in the diurnal temperature range (DTR) is small. This study focuses on understanding causes of the rapid summer warming and associated temperature extreme changes. A set of experiments using the atmospheric component of the state-of-the-art HadGEM3 global climate model have been carried out to quantify relative roles of changes in sea surface temperature (SST)/sea ice extent (SIE), anthropogenic greenhouse gases (GHGs), and anthropogenic aerosols (AAer). Results indicate that the model forced by changes in all forcings reproduces many of the observed changes since the mid-1990s over Western Europe. Changes in SST/SIE explain 62.2 ± 13.0 % of the area averaged seasonal mean warming signal over Western Europe, with the remaining 37.8 ± 13.6 % of the warming explained by the direct impact of changes in GHGs and AAer. Results further indicate that the direct impact of the reduction of AAer precursor emissions over Europe, mainly through aerosol-radiation interaction with additional contributions from aerosol-cloud interaction and coupled atmosphere-land surface feedbacks, is a key factor for increases in annual hottest day temperature and in frequency of summer days. It explains 45.5 ± 17.6 % and 40.9 ± 18.4 % of area averaged signals for these temperature extremes. The direct impact of the reduction of AAer precursor emissions over Europe acts to increase DTR locally, but the change in DTR is countered by the direct impact of GHGs forcing. In the next few decades, greenhouse gas concentrations will continue to rise and AAer precursor emissions over Europe and North America will continue to decline. Our results suggest that the changes in summer seasonal mean SAT and temperature extremes over Western Europe since the mid-1990s are most likely to be sustained or amplified in the near term, unless other factors intervene. [ABSTRACT FROM AUTHOR]

Anthropogenic nutrient inputs are one of the most important factors contributing to eutrophication of coastal waters. Coastal upwelling regions are naturally highly variable, exhibiting faster flushing and lower retention times than estuarine systems. As such, these regions are considered more resilient to anthropogenic influences than other coastal waters. Recent studies have shown our perception of the sustainability of these systems may be flawed and that anthropogenic nutrients can have an impact at local and regional spatial scales within these larger upwelling ecosystems. Maintenance of an outfall pipe discharging wastewater effluent to the Southern California Bight (SCB) provided an opportunity to study effects of anthropogenic nutrient inputs on a near-shore coastal ecosystem. The diversion of wastewater effluent from a primary, offshore outfall to a secondary, near-shore outfall set up a large-scale, in situ experiment allowing researchers to track the fate of wastewater plumes as they were “turned off” in one area and “turned on” in another. In this introduction to a special issue, we synthesize results of one such wastewater diversion conducted by the Orange County Sanitation District (OCSD) during fall 2012. Anthropogenic nitrogen (N) from point-source discharges altered biogeochemical cycling and the community composition of bacteria and phytoplankton. Nitrification of ammonium to nitrate in wastewater effluent close to outfalls constituted a significant source of N utilized by the biological community that should be considered in quantifying “new” production. The microbial-loop component of the plankton community played a significant role, exemplified by a large response of heterotrophic bacteria to wastewater effluent that resulted in nutrient immobilization within the bacterial food web. This response, combined with the photosynthetic inhibition of phytoplankton due to disinfection byproducts, suppressed phytoplankton responses. Our findings have ramifications for future studies and regulatory monitoring, emphasizing the need to consider chemical and biological responses to wastewater effluent in assessing effects of anthropogenic nutrient inputs on urbanized coastal ecosystems. [ABSTRACT FROM AUTHOR]

Lung Deposited Surface Area (LDSA) has been identified as a potential metric for the correlation of a physical aerosol particle properties with health outcomes. Currently, there is little urban LDSA data. As a case study, we investigated measurements of LDSA (alveolar) concentrations in a mid-size European city. LDSA and associated measurements were carried out over 1.5 years at an urban background site in Leicester, UK. Average LDSA concentrations in the cold (November–April) and warm (May–October) seasons of UK were 37 and 23 μm 2 cm −3 , respectively. LDSA correlates well (R 2 = 0.65–0.7, r = 0.77–0.8) with traffic related pollutants, such as equivalent black carbon (eBC) and NO X . We also report for the first time in the UK the correlation between an empirically derived LDSA and eBC. Furthermore, the effect of wind speed and direction on the LDSA was explored. Higher LDSA concentrations are observed at low wind speeds (1–2 m s −1 ), owing to local traffic emissions. In addition, the diurnal variation of LDSA showed a second peak in the afternoon under warm and relatively clean atmospheric conditions, which can be attributed to photochemical new particle formation (NPF) and growth into the Aitken mode range. These NPF events increased the average background LDSA concentrations from 15.5 to 35.5 μm 2 cm −3 , although they might not be health-relevant. Overall, the results support the notion that local traffic emissions are a major contributor to observed LDSA concentrations with a clear seasonal pattern with higher values during winter. [ABSTRACT FROM AUTHOR]

Climate change has been shown to impact the mean climate state and climate extremes. Though climate extremes have the potential to disrupt society, extreme conditions are rare by definition. In contrast, mild weather occurs frequently and many human activities are built around it. We provide a global analysis of mild weather based on simple criteria and explore changes in response to radiative forcing. We find a slight global mean decrease in the annual number of mild days projected both in the near future (−4 days per year, 2016-2035) and at the end of this century (−10 days per year, 2081-2100). Projected seasonal and regional redistributions of mild days are substantially greater. These changes are larger than the interannual variability of mild weather caused by El Niño-Southern Oscillation. Finally, we show an observed global decrease in the recent past, and that observed regional changes in mild weather resemble projections. [ABSTRACT FROM AUTHOR]

Rift Valley fever (RVF) is a vector-borne viral disease widespread in Africa. The primary cycle involves mosquitoes and wild and domestic ruminant hosts. Humans are usually contaminated after contact with infected ruminants. As many environmental, agricultural, epidemiological, and anthropogenic factors are implicated in RVF spread, the multidisciplinary One Health approach was needed to identify the drivers of RVF epidemics in Madagascar. We examined the environmental patterns associated with these epidemics, comparing human and ruminant serological data with environmental and cattle-trade data. In contrast to East Africa, environmental drivers did not trigger the epidemics: They only modulated local Rift Valley fever virus (RVFV) transmission in ruminants. Instead, RVFV was introduced through ruminant trade and subsequent movement of cattle between trade hubs caused its long-distance spread within the country. Contact with cattle brought in from infected districts was associated with higher infection risk in slaughterhouse workers. The finding that anthropogenic rather than environmental factors are the main drivers of RVF infection in humans can be used to design better prevention and early detection in the case of RVF resurgence in the region. [ABSTRACT FROM AUTHOR]

Arctic sea ice extent (SIE) has decreased over recent decades, with record-setting minimum events in 2007 and again in 2012. A question of interest across many disciplines concerns the extent to which such extreme events can be attributed to anthropogenic influences. First, a detection and attribution analysis is performed for trends in SIE anomalies over the observed period. The main objective of this study is an event attribution analysis for extreme minimum events in Arctic SIE. Although focus is placed on the 2012 event, the results are generalized to extreme events of other magnitudes, including both past and potential future extremes. Several ensembles of model responses are used, including two single-model large ensembles. Using several different metrics to define the events in question, it is shown that an extreme SIE minimum of the magnitude seen in 2012 is consistent with a scenario including anthropogenic influence and is extremely unlikely in a scenario excluding anthropogenic influence. Hence, the 2012 Arctic sea ice minimum provides a counterexample to the often-quoted idea that individual extreme events cannot be attributed to human influence. [ABSTRACT FROM AUTHOR]

The response of atmospheric heat transport to anthropogenic warming is determined by the anomalous meridional energy gradient. Feedback analysis offers a characterization of that gradient and hence reveals how uncertainty in physical processes may translate into uncertainty in the circulation response. However, individual feedbacks do not act in isolation. Anomalies associated with one feedback may be compensated by another, as is the case for the positive water vapor and negative lapse rate feedbacks in the tropics. Here a set of idealized experiments are performed in an aquaplanet model to evaluate the coupling between the surface albedofeedback and other feedbacks, including the impact on atmospheric heat transport. In the tropics, the dynamical response manifests as changes in the intensity and structure of the overturning Hadley circulation. Only half of the range of Hadley cell weakening exhibited in these experiments is found to be attributable to imposed, systematic variations in the surface albedofeedback. Changes in extratropical clouds that accompany the albedo changes explain the remaining spread. The feedback-driven circulation changes are compensated by eddy energy flux changes, which reduce the overall spread among experiments. These findings have implications for the efficiency with which the climate system, including tropical circulation and the hydrological cycle, adjusts to high-latitude feedbacks over climate states that range from perennial or seasonal ice to ice-free conditions in the Arctic. [ABSTRACT FROM AUTHOR]

The annual "State of the Climate" report, published in the Bulletin of the American Meteorological Society (BAMS), has included a supplement since 2011 composed of brief analyses of the human influence on recent major extreme weather events. There are now several dozen extreme weather events examined in these supplements, but these studies have all differed in their data sources as well as their approaches to defining the events, analyzing the events, and the consideration of the role of anthropogenic emissions. This study reexamines most of these events using a single analytical approach and a single set of climate model and observational data sources. In response to recent studies recommending the importance of using multiple methods for extreme weather event attribution, results are compared from these analyses to those reported in the BAMS supplements collectively, with the aim of characterizing the degree to which the lack of a common methodological framework may or may not influence overall conclusions. Results are broadly similar to those reported earlier for extreme temperature events but disagree for a number of extreme precipitation events. Based on this, it is advised that the lack of comprehensive uncertainty analysis in recent extreme weather attribution studies is important and should be considered when interpreting results, but as yet it has not introduced a systematic bias across these studies. [ABSTRACT FROM AUTHOR]

In this study, a groundwater (GW) extraction scheme was incorporated into the Community Earth System Model, version 1.2.0 (CESM1.2.0), to create a new version called CESM1.2_GW, which was used to investigate hydrologic and climatic responses to anthropogenic GW extraction on a global scale. An ensemble of 41-yr simulations with and without GW extraction (estimated based on local water supply and demand) was conducted and analyzed. The results revealed that GW extraction and water consumption caused drying in deep soil layers but wetting in upper layers, along with a rapidly declining GW table in areas with the most severe GW extraction, including the central United States, the north China plain, and northern India and Pakistan. The atmosphere also responded to GW extraction, with cooling at the 850-hPa level over northern India and Pakistan and a large area in northern China and central Russia. Increased precipitation occurred in the north China plain due to increased evapotranspiration from irrigation. Decreased precipitation occurred in northern India because the Indian monsoon and its transport of water vapor were weaker as a result of cooling induced by GW use. Additionally, the background climate change may complicate the precipitation responses to the GW use. Local terrestrial water storage was shown to be unsustainable at the current high GW extraction rate. Thus, a balance between reduced GW withdrawal and rapid economic development must be achieved in order to maintain a sustainable GW resource, especially in regions where GW is being overexploited. [ABSTRACT FROM AUTHOR]

A review of the published works on the use of different methods of analysis for studying anthropogenic pollution of environmental objects with platinum group metals (PGMs) for 2011-2013 is presented. The results of the recent studies on the content of PGMs in environmental objects of big cities are provided. [ABSTRACT FROM AUTHOR]

The article discusses the role of Arctic sea ice and sea surface temperatures (SSTs) in the cold event in North America in February 2015. Topics include the impact of natural atmospheric variability, anthropogenic activity to the increase in the probability of the cold spells in the region, and generalized Pareto distribution (GPD).

The article presents a study which investigates the role of El Niño and human-induced climate change to the increase in likelihood of heat and drought in Indonesia in July-October 2015. The study used the temperature and precipitation to assess the extreme event in the country. Results show that the dry season was attributed to El Niño and climate change.

The article presents a study which examines the human influence on the extreme summer temperature events in western China on June 12 to August 10, 2015. The study used the optimal fingerprinting method for the analysis of daily maximum (TXx), and daily minimum (TNx) temperatures. Results show the increase in the probability of the event due to the anthropogenic forcing (ANT) and combination of natural variability of the climate system and human emission of greenhouse gases.

The article presents a study which examined the European heat wave in 2015. It mentions that climate model experiments were conducted to determine the roles of changes in sea ice extent (SIE) and sea surface temperature (SST) and anthropogenic forcings such as anthropogenic aerosol (AA) and greenhouse gas (GHG) on the summer heat wave. It shows that a major factor for development of heat wave was anthropogenic forcings.

The article presents a study which examined the causes of warm surface temperatures observed for the global mean, equatorial central Pacific, and India in 2015. It mentions that decadal variability of Niño-4 region temperature anomalies was evaluated and global mean analysis was conducted. It concludes that anthropogenic warming was mostly to blame, according to Coupled Model Intercomparison Project phase 5 (CMIP5) simulations.

Due to the rise in anthropogenic greenhouse gas concentrations, the earth's climate is expected to change, with precipitation being reduced in some areas resulting in growth-limiting drought and, as a consequence, reduced plant productivity. We investigated the physiological and growth responses of cassava ( Manihot esculenta Crantz) to approximate present-day ambient (390 μL L −1 ) and elevated (750 μL L −1 ) atmospheric CO 2 concentrations under well-watered and water deficit conditions, aiming at understanding how cassava would face those problems. Water deficits led to reductions in the Leaf Elongation Rate of plants grown at ambient as well as CO 2 -enriched concentrations. However, plants grown at 750 μL L −1 of CO 2 maintained leaf growth two days longer than plants grown at 390 μL L −1 . Three Days After Withholding Water (DAWW), photosynthesis and stomatal conductance were reduced in plants grown under ambient CO 2 , while in plants under an elevated CO 2 concentration, these physiological functions remained similar to that of control plants grown under good water availability. Five DAWW plants grown with 750 μL L −1 continued to have enhanced gas exchange compared with plants grown under 390 μL L −1 . Under drought stress, the instantaneous transpiration efficiency was always greatest for plants grown under elevated CO 2 . The positive response of elevated CO 2 levels on total dry mass was 61% in the water-stressed plants and only 20% for the plants grown under good water availability. Stomatal limitation was an important factor reducing CO 2 assimilation in cassava growing under drought conditions. [ABSTRACT FROM AUTHOR]