Investigating the Long-Range Transport of Aerosol Plumes Following the Amazon Fires (August 2019): A Multi-Instrumental Approach from Ground-Based and Satellite Observations

Hassan Bencherif (1, 2) , Nelson Bègue (1) , Damaris Kirsch Pinheiro (3) , David Jean Du Preez (1, 4) , Jean-Maurice Cadet (1) , Fábio Juliano da Silva Lopes (5) , Lerato Shikwambana (6) , Eduardo Landulfo (7) , Thomas Vescovini (1) , Casper Labuschagne (8) , Jonatan João Silva (7, 9) , Vagner Anabor (3) , Pierre-François Coheur (10) , Nkanyiso Mbatha (11) , Juliette Hadji-Lazaro (12) , Venkataraman Sivakumar (2) , Cathy Clerbaux (10, 12)

1 LACy - Laboratoire de l'Atmosphère et des Cyclones
2 UKZN - University of KwaZulu-Natal [Durban, Afrique du Sud]
3 UFSM - Universidade Federal de Santa Maria = Federal University of Santa Maria [Santa Maria, RS, Brazil]
4 Department of Geography, Geoinformatics and Meteorology [Pretoria]
5 Unifesp - Federal University of Sao Paulo
6 SANSA - South African National Space Agency
7 IPEN/CNEN-SP - Instituto de Pesquisas Energéticas e Nucleares [São Paulo]
8 SAWS - South African Weather Service
9 UFOB - Universidade Federal do Oeste da Bahia
10 SQUARES - Spectroscopy, Quantum Chemistry and Atmospheric Remote Sensing
11 University of ZuluLand
12 TROPO - LATMOS

Despite a number of studies on biomass burning (BB) emissions in the atmosphere, observation of the associated aerosols and pollutants requires continuous efforts. Brazil, and more broadly Latin America, is one of the most important seasonal sources of BB, particularly in the Amazon region. Uncertainty about aerosol loading in the source regions is a limiting factor in terms of understanding the role of aerosols in climate modelling. In the present work, we investigated the Amazon BB episode that occurred during August 2019 and made the international headlines, especially when the smoke plumes plunged distant cities such as São Paulo into darkness. Here, we used satellite and ground-based observations at different locations to investigate the long-range transport of aerosol plumes generated by the Amazon fires during the study period. The monitoring of BB activity was carried out using fire related pixel count from the moderate resolution imaging spectroradiometer (MODIS) onboard the Aqua and Terra platforms, while the distribution of carbon monoxide (CO) concentrations and total columns were obtained from the infrared atmospheric sounding interferometer (IASI) onboard the METOP-A and METOP-B satellites. In addition, AERONET sun-photometers as well as the MODIS instrument made aerosol optical depth (AOD) measurements over the study region. Our datasets are consistent with each other and highlight AOD and CO variations and long-range transport of the fire plume from the source regions in the Amazon basin. We used the Lagrangian transport model FLEXPART (FLEXible PARTicle) to simulate backward dispersion, which showed good agreement with satellite and ground measurements observed over the study area. The increase in Rossby wave activity during the 2019 austral winter the Southern Hemisphere may have contributed to increasing the efficiency of large-scale transport of aerosol plumes generated by the Amazon fires during the study period.

Mots clés: biomass burning; Amazonia; Brazil; aerosols; plume transport

Domaines: Océan, Atmosphère

Hassan Bencherif, Nelson Bègue, Damaris Kirsch Pinheiro, David Jean Du Preez, Jean-Maurice Cadet, et al.. Investigating the Long-Range Transport of Aerosol Plumes Following the Amazon Fires (August 2019): A Multi-Instrumental Approach from Ground-Based and Satellite Observations. Remote Sensing, 2020, Advances in Remote Sensing of Biomass Burning, 12 (22), pp.3846. ⟨10.3390/rs12223846⟩. ⟨hal-03027089⟩