Mesoscale convective systems over the Amazon basin in a changing climate under global warming

• Published in: Climate dynamics Vol. 61; no. 3-4; pp. 1815 - 1827
• Main Authors: Rehbein, Amanda, Ambrizzi, Tercio
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-08-2023; Springer; Springer Nature B.V
• Subjects: Basins (Geology); Climate change; Climatic changes; Climatology; Clouds; Convection (Meteorology); Earth and Environmental Science; Earth Sciences; Environmental aspects; Environmental impact; General circulation models; Geophysics/Geodesy; Global climate; Global warming; Intercomparison; Mesoscale convective systems; Mesoscale phenomena; Mesoscale systems; Modelling; Oceanography; Precipitation; River basins; Tropical environment; Tropical environments; Water circulation; Watersheds; Brazil; Climate change; CMIP6; NICAM; Amazon basin; Mesoscale convective systems; Global cloud resolving models
• ISSN: 0930-7575; 1432-0894
• DOI: 10.1007/s00382-022-06657-8

Climate change is imminent and threatens the largest watershed in the world, the Amazon basin. As general circulation models may fail to represent cloud-scale phenomena, precipitation in a changing climate under global warming is still a factor of great uncertainty, especially in Tropical regions. In this study, we used long-term high-resolution simulations from a global cloud-resolving model under the scope of the Coupled Model Intercomparison Project (CMIP6) to verify the climate change impacts on the mesoscale convective systems (MCSs) over the Amazon basin. We generated a complete spatial, temporal, and statistical characterization of the MCSs for the past (1950–1960), present (2000–2010), and near-future (2040–2050). We found that MCSs are a critical mechanism for precipitation, especially in austral winter. The simulations are consistent with the observed precipitation and MCSs patterns over the Amazon basin, indicating that MCSs are less frequent compared to the past and are expected to continuously decline in the near-future. Most decreases are projected from September to December, while an increase between June to August, mainly in the southern portion of the Amazon basin. In addition, the investigation presented here shows the great potential of using a global cloud-resolving model under the CMIP6 scope to investigate mesoscale systems in a warming climate.