Sahel rainfall is dynamically linked to the global Hadley cell and to the regional monsoon circulation. It is therefore susceptible to forcings from remote oceans and regional land alike. Warming of the oceans enhances the stability of the tropical atmosphere and weakens deep ascent in the Hadley circulation. Warming of the Sahara and of the nearby oceans changes the structure and position of the regional shallow circulation and allows more of the intense convective systems that determine seasonal rain accumulation. These processes can explain the observed interannual to multidecadal variability. Sea surface temperature anomalies were the dominant forcing of the drought of the 1970s and 1980s. In most recent decades, seasonal rainfall amounts have partially recovered, but rainy season characteristics have changed: rainfall is more intense and intermittent and wetting is concentrated in the late rainy season and away from the west coast. Similar subseasonal and subregional differences in rainfall trends characterize the simulated response to increased greenhouse gases, suggesting an anthropogenic influence. While uncertainty in future projections remains, confidence in them is encouraged by the recognition that seasonal mean rainfall depends on large-scale drivers of atmospheric circulations that are well resolved by current climate models. Nevertheless, observational and modeling efforts are needed to provide more refined projections of rainfall changes, expanding beyond total accumulation to metrics of intraseasonal characteristics and risk of extreme events, and coordination between climate scientists and stakeholders is needed to generate relevant information that is useful even under deep uncertainty. This article is categorized under:Paleoclimates and Current Trends > Modern Climate Change.
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http://dx.doi.org/10.1002/wcc.591 | DOI Listing |
Heliyon
January 2025
Institute of Geo-information and Earth Observation Sciences, Mekelle University, P.O. Box 231, Mekelle, Ethiopia.
of long-term and future climate variability is crucial for impact assessment studies in drought-prone areas like the Giba basin in northern Ethiopia. This study has applied the statistical downscaling model (SDSM) and (De Martonne and Pinna combinative) aridity index methods to evaluate the climate system of the Giba basin. Historical data (1961-2019) from seven meteorological stations and global grided data were used for future climate projections (2020-2100) under the three emission scenarios (RCPs 2.
View Article and Find Full Text PDFMicrobiol Res
January 2025
Key Laboratory of Vegetation Ecology, Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun, China; State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun, China. Electronic address:
Extreme climatic events, such as drought, can significantly alter belowground microbial diversity and species interactions, leading to unknown consequences for ecosystem functioning. Here, we simulated a drought gradient by removing 30 %, 50 %, and 70 % of precipitation in a semi-arid grassland over five years. We assessed the effects of drought on bacterial and fungal diversity, as well as on their species interactions.
View Article and Find Full Text PDFSci Rep
January 2025
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, China.
This study examines the complexities of climate modeling, specifically in the Panj River Basin (PRB) in Central Asia, to evaluate the transition from CMIP5 to CMIP6 models. The research aimed to identify differences in historical simulations and future predictions of rainfall and temperature, examining the accuracy of eight General Circulation Models (GCMs) used in both CMIP5 (RCP4.5 and 8.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Astronomy, Astrophysics and Space Engineering, Indian Institute of Technology Indore, Indore, Madhya Pradesh, 453552, India.
Arctic precipitation plays a crucial role in shaping the surface mass balance of Arctic sea ice and has wide-ranging impacts on local climate, ecosystems, and global sea level dynamics. With the Arctic undergoing warming trends, historical data and climate models indicate a shift from primarily snowfall to a rise in liquid and mixed forms of precipitation. This study tried to explain the microphysical characteristics and atmospheric conditions associated with different forms of precipitation and their transitions.
View Article and Find Full Text PDFTicks Tick Borne Dis
January 2025
Department of Health, Sport and Bioscience. University of East London, Water Lane, Stratford E15 4LZ, United Kingdom. Electronic address:
The interplay of biotic and abiotic factors driving Ixodes ricinus abundance trends are not fully understood. Machine learning (ML) approaches are being increasingly used to explore this and predict future abundance patterns of this species, however, the studies focusing on this to date have had limitations (including short study duration, limited sample size, narrow geographical range and use of a single ML model). This study was undertaken to address these limitations by applying 11 predictive ML models (across three data clustering techniques) to a large I.
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