TY - JOUR
T1 - Historical and future trends in South Asian monsoon low pressure systems in a high-resolution model ensemble
AU - Vishnu, S.
AU - Boos, William R.
AU - Collins, William D.
N1 - Code availability
Code to produce the figures is available from the corresponding author on request.
Data availability
The monsoon low-pressure system track data for reanalyses was obtained from the Zenodo archive (https://zenodo.org/record/3890646#.ZAmsIi9U1QI). The ERA5 data set was obtained from the Copernicus Climate Change Service Climate Data Store (CDS) website (at https://cds.climate.copernicus.eu), accessed on 1 March 2021. Tropical Rainfall Measuring Mission (TRMM) daily precipitation data was downloaded from the NASA GSFC website (https://disc.gsfc.nasa.gov/datasets/TRMM_3B42_Daily_7/summary). The HighResMIP model data was downloaded from The Earth System Grid Federation infrastructure (ESGF) archive (https://esgf-node.llnl.gov/search/cmip6/). All data used in the paper are acknowledged in the Methods section.
Acknowledgements
This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research, Climate and Environmental Sciences Division, Regional & Global Model Analysis (RGMA) Program, under Award Numbers DE-AC02-05CH11231 and DE-SC0019367. WRB and WDC were supported under RGMA’s Calibrated and Systematic Characterization, Attribution, and Detection of Extremes (CASCADE) Scientific Focus Area. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231 using NERSC awards BER-ERCAPm1517 and BER-ERCAPm3310. The authors also acknowledge support from the Earth System Science Organization, Ministry of Earth Sciences, Government of India (Grant IITM/MM-II/ Univ_California_USA/INT-3) under the Monsoon Mission. We acknowledge the World Climate Research Programme, which, through its Working Group on Coupled Modelling, coordinated and promoted CMIP6. We thank the climate modeling groups for producing and making available their model output, the Earth System Grid Federation (ESGF) for archiving the data and providing access, and the multiple funding agencies who support CMIP6 and ESGF. The authors thank the modeling groups within PRIMAVERA (a European Union Horizon 2020 project under Grant Agreement 641727) for producing the multi-model simulations and providing the climate model outputs via the Earth System Grid Federation (ESGF). The authors greatly appreciate Malcolm Roberts and Jon Seddon (UK Met Office Hadley Centre) for their help in accessing the model data through the UK Centre for Environmental Data Analysis’s JASMIN platform.
PY - 2023/12
Y1 - 2023/12
N2 - Historical trends in monsoon low pressure systems (LPS), the dominant rain-bearing weather system of South Asia, have been difficult to assess due to changes in the observing network. Future projections have also remained uncertain because prior studies concluded that many coarse-resolution climate models do not accurately simulate LPS. Here, we examine changes in South Asian monsoon LPS simulated by an ensemble of global models, including some with high spatial resolution, that we show skillfully represent LPS. In the ensemble mean, the number of strong LPS (monsoon depressions) decreased over the last 65 years (1950–2014) by about 15% while no trend was detected for weaker LPS (monsoon lows). The reduction in depression counts then moderated, yielding no trend in the periods 1980–2050 or 2015–2050. The ensemble mean projects a shift in genesis from ocean to land and an increase in LPS precipitation of at least 7% K−1, which together contribute to a projected increase in seasonal mean and extreme precipitation over central India.
AB - Historical trends in monsoon low pressure systems (LPS), the dominant rain-bearing weather system of South Asia, have been difficult to assess due to changes in the observing network. Future projections have also remained uncertain because prior studies concluded that many coarse-resolution climate models do not accurately simulate LPS. Here, we examine changes in South Asian monsoon LPS simulated by an ensemble of global models, including some with high spatial resolution, that we show skillfully represent LPS. In the ensemble mean, the number of strong LPS (monsoon depressions) decreased over the last 65 years (1950–2014) by about 15% while no trend was detected for weaker LPS (monsoon lows). The reduction in depression counts then moderated, yielding no trend in the periods 1980–2050 or 2015–2050. The ensemble mean projects a shift in genesis from ocean to land and an increase in LPS precipitation of at least 7% K−1, which together contribute to a projected increase in seasonal mean and extreme precipitation over central India.
UR - https://www.scopus.com/pages/publications/85176013395
U2 - 10.1038/s41612-023-00502-3
DO - 10.1038/s41612-023-00502-3
M3 - Article
AN - SCOPUS:85176013395
SN - 2397-3722
VL - 6
SP - 1
EP - 11
JO - npj Climate and Atmospheric Science
JF - npj Climate and Atmospheric Science
IS - 1
M1 - 182
ER -
SDG 13 Climate Action