Interactions between biomass-burning aerosols and clouds over Southeast Asia: Current status, challenges, and perspectives

Radiative Effect of Springtime Biomass-Burning Aerosols over Northern Indochina during 7-SEAS/BASELInE 2013 Campaign

“…The impact of BB on air quality over Southeast Asia was evaluated within the framework of BASE-ASIA campaign by using chemical transport modelling (Fu et al, 2012;Huang et al, 2013). Moreover, some recent studies also emphasized the BB emissions from Indochina region and explained their impact on regional air quality, atmospheric radiation, hydrological cycle, and climate (e.g., Lin et al, 2013;Tsay et al, 2013;Lin et al, 2014;Tsay et al, 2016) by using in-situ measurements (e.g., Chuang et al, 2013b;Wang et al, 2015;Chuang et al, 2016;Hsiao et al, 2016;Khamkaew et al, 2016;Pantina et al, 2016;Sayer et al, 2016), satellite observations (e.g., Hsu et al, 2003;Huang et al, 2011;Campbell et al, 2013;Lee et al, 2016b), remote sensing Reid et al, 2013), and modeling studies (Fu et al, 2012;Loftus et al, 2016) within the 7-SEAS framework. Wang et al (2015) investigated the presence of strongly absorbing (single-scattering albedo ≈0.88 and absorption angstrom exponent ≈1.5) carbonaceous aerosols within the planetary boundary layer (PBL) over northern Indochina in 2014 spring.…”

Coupled Aerosol-Cloud Systems over Northern Vietnam during 7-SEAS/BASELInE: A Radar and Modeling Perspective

“…Aerosol impacts on low-level Sc over land remain unclear given that far less attention has been paid to these clouds compared to marine Sc (cf. Klein and Hartmann, 1993;Lin et al, 2014), presumably given the critical role of the latter in modulating radiant energy and latent heat that affect weather and climate (Stephens and Greenwald, 1991;Lohmann and Feichter, 2005;Wood, 2012). Indeed, the semi-persistent low-level Sc systems that exist over northern Vietnam from November through April offer a unique opportunity to investigate a myriad of possible feedbacks between these cloud systems and BB aerosols.…”

“…During boreal spring in Southeast Asia (SEA), biomass-burning from natural forest fires and slashand-burn agricultural practices strongly modulates the atmospheric composition over northern SEA Reid et al, 2013, Tsay et al, 2016, andreferences therein). The chemical and aerosol species associated with the burning degrade the regional air quality and trigger adverse health effects in the local population (cf.., Huang et al, 2013;Lin et al, 2014), and can additionally alter the lifecycles of clouds and distribution of precipitation through radiative and microphysical effects (Graf et al, 2009;Lee et al, 2014).…”

“…Future simulations will also incorporate time-dependent meteorological forcing based output from week-long simulations over the SEA region using the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) (Grell et al, 2005;Fast et al, 2006). Aerosol emissions, transport, and aging processes predicted by WRF-CHEM and constrained by collaborative 7-SEAS/BASELInE measurements (e.g., Lin et al, 2013;Tsay et al, 2013;Lin et al, 2014) will further permit more realistic aerosol input into the GCE.…”

Evaluation of Atmospheric PCDD/Fs at Two High-Altitude Stations in Vietnam and Taiwan during Southeast Asia Biomass Burning

“…Biomass burning hotspots are mostly located in tropical or subtropical regions, such as South America, Africa, Southeast Asia, and Australia. Pollutants emitted from biomass burning, such as particulate matter or chemical gases like CO, SO x , NO x , and VOCs, can negatively impact human health (Gullett et al, 2006;Feng and Christopher, 2013;Lin et al, 2014). Biomass burning activities in Southeast Asia combined with monsoonal meteorological condition during the regional dry season can also enhance transport of emitted pollutants, including PCDD/Fs to downwind areas through long-range transport (Jian and Fu, 2013).…”