Dispersion of Smoke Plumes over South America

Earth Interactions

article

Mark R. Jury¹  América R. Gaviria Pabón¹ 

[1] Physics Department, University of Puerto Rico Mayaguez;Geography Department, University of Zululand

关键词: South America;    Forest fires;    Trace gases;    Dispersion;   

DOI  :  10.1175/EI-D-20-0004.1

学科分类：地球科学(综合)

来源: American Geophysical Union

【 摘 要 】

Satellite and reanalysis products are used to study the atmospheric environment, aerosols, and trace gases in smoke plumes over South America in the period 2000–18. Climatic conditions and fire density maps provide context to link biomass burning across the southern Amazon region (5°–15°S, 50°–70°W) to thick near-surface plumes of trace gases and fine aerosols. Intraseasonal weather patterns that underpin greater fire emissions in the dry season (July–October) are exacerbated by high pressure over a cool eastern Pacific Ocean, for example in September 2007. Smoke-plume dispersion simulated with HYSPLIT reveals a slowing of westward transport between sources in eastern Brazil and the Andes Mountains. During cases of thick smoke plumes over southern Amazon, an upper ridge and sinking motions confine trace gases and fine aerosols below 4 km. Long-term warming, which tends to coincide with the zone of biomass burning, is +0.03°C yr −1 in the air and +0.1°C yr −1 at the land surface. Our study suggests that weather conditions promoting fire emissions also tend to limit dispersion.

【 授权许可】

Unknown