Arbain Ardhi Adhary, Imasu Ryoichi
Research Center for Climate and Atmosphere, Research Organization for Earth Sciences and Maritime, National Research and Innovation Agency, Serpong, Tangerang Selatan 15314, Indonesia.
Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa 277-8564, Chiba, Japan.
Sensors (Basel). 2025 Sep 7;25(17):5588. doi: 10.3390/s25175588.
Underestimation of PM emissions from the agricultural sector persists as a major difficulty for air quality studies, partly because of underutilization of high-resolution observation platforms for constructing a global emissions inventory. Coarse-resolution products used for such purposes often miss fine-scale burnt areas created by stubble-burning practices, which are primary sources of agricultural PM emissions. For this study, we used the high-resolution Sentinel-2 observations to examine the spatiotemporal variability of burnt areas in Punjab, a major hotspot of agricultural burning in India, during the post-monsoon fire season (October-December) in 2022-2024. The results highlight the Sentinel-2 capability of detecting more than 34,000 km of burnt areas (approx. 68% of Punjab's total area) as opposed to the less than 7000 km (approx. 12% of Punjab's total area) detected by MODIS. The study also reveals, in unprecedented detail, multi-annual spatial and temporal shifting of burning events from northern to central and southern Punjab. This detection discrepancy has led to marked disparities in estimated monthly emissions, with approximately 217.3 million tons of PM emitted in October 2022 compared to 8.7 million tons found by EDGAR v.8.1. This underscores higher-resolution observation systems intended to support construction of a global PM emissions inventory.
农业部门颗粒物排放的低估仍然是空气质量研究的一大难题，部分原因是在构建全球排放清单时，高分辨率观测平台未得到充分利用。用于此类目的的低分辨率产品往往会遗漏由秸秆焚烧造成的细粒度燃烧区域，而秸秆焚烧是农业颗粒物排放的主要来源。在本研究中，我们利用高分辨率的哨兵2号观测数据，研究了印度农业焚烧的主要热点地区旁遮普邦在2022 - 2024年季风后火灾季节（10月至12月）燃烧区域的时空变化。结果表明，哨兵2号能够检测到超过34000平方千米的燃烧区域（约占旁遮普邦总面积的68%），而中分辨率成像光谱仪（MODIS）检测到的燃烧区域不到7000平方千米（约占旁遮普邦总面积的12%）。该研究还以前所未有的细节揭示了燃烧事件从旁遮普邦北部向中部和南部的多年时空转移。这种检测差异导致了估计月排放量的显著差异，2022年10月估计排放了约2.173亿吨颗粒物，而全球大气研究排放数据库第8.1版（EDGAR v.8.1）显示的排放量为870万吨。这凸显了旨在支持构建全球颗粒物排放清单的高分辨率观测系统的重要性。
