Marine emissions of methanethiol increase aerosol cooling in the Southern Ocean
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View abstract on PubMed
Summary
This summary is machine-generated.Marine methanethiol (MeSH) emissions, previously unexplored, significantly impact climate. This study quanties MeSH emissions, revealing their crucial role in aerosol formation and climate cooling, particularly in the Southern Ocean.
Area Of Science
- Atmospheric Chemistry
- Ocean-Atmosphere Interactions
- Climate Science
Background
- Oceanic dimethyl sulfide (DMS) is a key precursor to climate-cooling aerosols.
- Marine sulfur cycling predominantly produces methanethiol (MeSH), a volatile compound that is difficult to measure.
- The global emissions and climate impact of MeSH remain largely unknown.
Purpose Of The Study
- To quantify global marine methanethiol (MeSH) emissions.
- To investigate the climate impact of MeSH emissions using a global chemistry-climate model.
- To assess the role of MeSH in atmospheric processes and its influence on climate models.
Main Methods
- Compilation of a global database of seawater MeSH concentrations.
- Statistical analysis to identify predictors of MeSH concentrations.
- Development of monthly global marine MeSH emission fields.
- Implementation of MeSH emissions into a global chemistry-climate model.
Main Results
- Global marine MeSH emissions were quantified and mapped.
- MeSH emissions increase sulfate aerosol burden by 30-70% over the Southern Ocean.
- MeSH emissions enhance aerosol cooling, deplete oxidants, and increase DMS lifetime.
- Accounting for MeSH reduces radiative bias in climate models for the Southern Ocean.
Conclusions
- Methanethiol (MeSH) is a significant, previously unquantified, contributor to marine aerosol production.
- MeSH emissions play a crucial role in Southern Ocean atmospheric chemistry and climate.
- Incorporating MeSH emissions improves the accuracy of global climate models.
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