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In the latter half of the twentieth century, a significant climate phenomenon diurnal asymmetric warming emerged, wherein global land surface temperatures increased more rapidly during the night than during the day. However, recent episodes of global brightening and regional droughts and heatwaves have brought notable alterations to this asymmetric warming trend. Here, we re-evaluate sub-diurnal temperature patterns, revealing a substantial increase in the warming rates of daily maximum temperatures (Tmax), while daily minimum temperatures have remained relatively stable. This shift has resulted in a reversal of the diurnal warming trend, expanding the diurnal temperature range over recent decades. The intensified Tmax warming is attributed to a widespread reduction in cloud cover, which has led to increased solar irradiance at the surface. Our findings underscore the urgent need for enhanced scrutiny of recent temperature trends and their implications for the wider earth system.

Management of forest plantations is a natural based solution to the global‐scale mitigation of climate change; however, the role of carbon sequestration remains poorly understood, and this is hampered by a lack of detailed distribution on the global forest plantations. For the first time, we generated a global spatial distribution for forest plantations (GSDFP) during 2015 at a spatial resolution of 250 m using hierarchical extraction based on a machine learning algorithm taking time series of MODIS and ALOS PALSAR imagery as the source data, and finally estimates the biomass carbon stored in forest plantations. The resultant map was validated using reference samples visually interpreted, as well as reference samples collected from previous studies, and inter‐compared with statistical forest plantation area and regional forest plantation maps, and the GSDFP was found to accurately represent the spatial distribution of forest plantations around the globe. Globally, forest plantations account for 7.35% (360.22 × 104 km2) of the global forest area and are estimated to contribute 4.60% (12.85 Pg C) of global forest biomass carbon. The forest plantation map and biomass carbon stock estimates will assist forest management and provide a benchmark for the estimation of the forest plantation carbon sink. Plain Language Summary: In recent decades, global reforestation and afforestation practices have aroused wide concern in the effectiveness of climate change mitigation. However, the lack of spatial explicit data on forest plantations is the vital limitation with respect to the corresponding biomass carbon stock estimates. In this study, we generated the global spatial distribution of forest plantations at a spatial resolution of 250 m, and further estimated the biomass carbon stock in forest plantations. We found that forest plantations contributed less biomass carbon stock to forests than their corresponding area. Our results can provide crucial scientific information for decisions on forest management and climate change mitigation. Key Points: A global distribution of forest plantations was created using machine learning, and the biomass carbon stock in forest plantations was estimatedThe proportion of plantation area in the forest (360.22 × 104 km2, 7.35%) is higher than that of biomass carbon stocks (12.85 Pg C, 4.60%)The forest plantations map and biomass carbon stock estimates will be beneficial for natural based solutions for climate mitigation [ABSTRACT FROM AUTHOR]

Interannual variability of the terrestrial ecosystem carbon sink is substantially regulated by various environmental variables and highly dominates the interannual variation of atmospheric carbon dioxide (CO2) concentrations. Thus, it is necessary to determine dominating factors affecting the interannual variability of the carbon sink to improve our capability of predicting future terrestrial carbon sinks. Using global datasets derived from machine-learning methods and process-based ecosystem models, this study reveals that the interannual variability of the atmospheric vapor pressure deficit (VPD) was significantly negatively correlated with net ecosystem production (NEP) and substantially impacted the interannual variability of the atmospheric CO2 growth rate (CGR). Further analyses found widespread constraints of VPD interannual variability on terrestrial gross primary production (GPP), causing VPD to impact NEP and CGR. Partial correlation analysis confirms the persistent and widespread impacts of VPD on terrestrial carbon sinks compared to other environmental variables. Current Earth system models underestimate the interannual variability in VPD and its impacts on GPP and NEP. Our results highlight the importance of VPD for terrestrial carbon sinks in assessing ecosystems' responses to future climate conditions. [ABSTRACT FROM AUTHOR]