Isolating Fast and Slow Response of the Regional Climate over Southeast Asia to Anthropogenic Aerosols using Variable Resolution-CESM
Abstract
Regional climate is expected to respond differently to diverse drivers of anthropogenic climate change, and the representation of the response is model and resolution dependent. We use a recently developed version of the Community Earth System Model (version 1.2) with variable resolution (VR-CESM) to examine the impact of anthropogenic aerosols on regional climate in Southeast Asia. In the model, we implement a refined grid with a horizontal resolution of 0.25 degree ( 28 km) over Southeast Asia and a resolution of 1 degree globally. The rapid and slow response to anthropogenic aerosols is disentangled by prescribing sea surface temperature (SST) and aerosol emissions at mid-20th century (1950) and present (2000) levels respectively. We examine the roles of the fast and slow response in shaping the regional climate response to increasing emissions of anthropogenic aerosols, focusing on changes in precipitation, near-surface temperature, and the Indian Monsoon and East Asian Monsoon strength. We also assess the fast and slow adjustments of temperature and water extremes and compare them with those from CESM simulations at coarser horizontal resolution. This study highlights the importance of SST feedbacks, associated with increasing anthropogenic aerosols, in driving changes in both regional climatology and extreme events and demonstrates the utility of VR-CESM in capturing these changes in regional climate.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2018
- Bibcode:
- 2018AGUFM.A51Q2468L
- Keywords:
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- 0305 Aerosols and particles;
- ATMOSPHERIC COMPOSITION AND STRUCTUREDE: 3311 Clouds and aerosols;
- ATMOSPHERIC PROCESSESDE: 3337 Global climate models;
- ATMOSPHERIC PROCESSESDE: 3359 Radiative processes;
- ATMOSPHERIC PROCESSES