Cloud and Aerosol Laboratory, Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan.
Cloud and Aerosol Laboratory, Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan.
Sci Total Environ. 2018 Aug 15;633:892-911. doi: 10.1016/j.scitotenv.2018.03.204. Epub 2018 Mar 28.
A large concentration of finer particulate matter (PM), the primary air-quality concern in northern peninsular Southeast Asia (PSEA), is believed to be closely related to large amounts of biomass burning (BB) particularly in the dry season. In order to quantitatively estimate the contributions of BB to aerosol radiative effects, we thoroughly investigated the physical, chemical, and optical properties of BB aerosols through the integration of ground-based measurements, satellite retrievals, and modelling tools during the Seven South East Asian Studies/Biomass-burning Aerosols & Stratocumulus Environment: Lifecycles & Interactions Experiment (7-SEAS/BASELInE) campaign in 2014. Clusters were made on the basis of measured BB tracers (Levoglucosan, nss-K, and NO) to classify the degree of influence from BB over an urban atmosphere, viz., Chiang Mai (18.795°N, 98.957°E, 354m.s.l.), Thailand in northern PSEA. Cluster-wise contributions of BB to PM, organic carbon, and elemental carbon were found to be 54-79%, 42-79%, and 39-77%, respectively. Moreover, the cluster-wise aerosol optical index (aerosol optical depth at 500nm≈0.98-2.45), absorption (single scattering albedo ≈0.87-0.85; absorption aerosol optical depth ≈0.15-0.38 at 440nm; absorption Ångström exponent ≈1.43-1.57), and radiative impacts (atmospheric heating rate ≈1.4-3.6Kd) displayed consistency with the degree of BB. PM during Extreme BB (EBB) was ≈4 times higher than during Low BB (LBB), whereas this factor was ≈2.5 for the magnitude of radiative effects. Severe haze (visibility≈4km) due to substantial BB loadings (BB to PM≈79%) with favorable meteorology can significantly impact the local-to-regional air quality and the, daily life of local inhabitants as well as become a respiratory health threat. Additionally, such enhancements in atmospheric heating could potentially influence the regional hydrological cycle and crop productivity over Chiang Mai in northern PSEA.
大量细颗粒物（PM）的集中，是东南亚半岛北部（PSEA）首要的空气质量关注点，被认为与大量生物质燃烧（BB）密切相关，尤其是在旱季。为了定量估计 BB 对气溶胶辐射效应的贡献，我们通过在 2014 年进行的七个东南亚研究/生物质燃烧气溶胶和层积云环境：生命周期和相互作用实验（7-SEAS/BASELInE）期间，整合地面测量、卫星反演和建模工具，彻底研究了 BB 气溶胶的物理、化学和光学特性。基于测量的 BB 示踪剂（左旋葡聚糖、nss-K 和 NO），将聚类应用于城市大气中 BB 影响程度的分类，例如泰国清迈（18.795°N，98.957°E，354m.s.l.）。发现 BB 对 PM、有机碳和元素碳的贡献分别为 54-79%、42-79%和 39-77%。此外，聚类的气溶胶光学指数（500nm 处的气溶胶光学深度≈0.98-2.45）、吸收（单散射反照率≈0.87-0.85；440nm 处的吸收气溶胶光学深度≈0.15-0.38；吸收 Ångström 指数≈1.43-1.57）和辐射影响（大气加热率≈1.4-3.6Kd）与 BB 的程度一致。极端 BB（EBB）期间的 PM 比低 BB（LBB）期间高约 4 倍，而在辐射效应的量级方面，这个因素约为 2.5。由于大量的 BB 负荷（BB 与 PM 的比例约为 79%）和有利的气象条件，严重的霾（能见度≈4km）会对当地到区域的空气质量、当地居民的日常生活以及呼吸健康造成严重威胁。此外，大气加热的这种增强可能会对 PSEA 北部清迈的区域水文循环和作物生产力产生影响。
