Abstract The Arabian Sea is an enclosed basin surrounded by land and is prone to receive large amount of aeolian dust from the continent. This can significantly impact surface water biogeochemical processes. In this study, an attempt has been made to quantify the amount of dust transported from Middle East region to Indian subcontinent (sampling site is Goa; 15.45°N 73.80°E; located in the northeast Arabian Sea) via the Arabian Sea. We identified a dust storm episode (02–10 April 2015) in the Arabian Peninsula and its propagation to the study site (Goa) using satellite data (MODIS and CALIPSO). The impact of the dust storm at Goa has been computed using ambient particulate matter concentration and satellite retrieved optical parameter. These observations were further substantiated using ground-based micro-pulse lidar measurement. The daily averaged lidar profile shows relatively high depolarization ratio (0.1–0.25), as well as high daily average backscatter coefficient (up to 0.08 Sr−1 Km−1) and extinction coefficient (up to 0.9 Km−1) during the storm period compared to non-dusty days. During this period, a two-layer (rich in non-spherical particle) structure with significantly high linear depolarization ratio is observed, indicating the impact of the dust storm at the coastal region of India. Ambient mass concentration of dust estimated using CALIPSO profile are comparable with the gravimetric mass measured from high volume sample collection. The back-trajectory analysis further supports the advection of air-mass from the Middle East to Eastern Arabian Sea. This study highlight the significant role of long-range transport in impacting dust load at the remote/receptor sites.

中文翻译：

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使用卫星和地面数据量化向印度半岛地区远距离输送的风尘 - 阿拉伯海沙尘暴期间的案例研究

摘要 阿拉伯海是一个被陆地包围的封闭盆地，容易接收来自大陆的大量风尘。这会显着影响地表水生物地球化学过程。在这项研究中，试图量化从中东地区通过阿拉伯海传输到印度次大陆（采样地点为果阿；15.45°N 73.80°E；位于阿拉伯海东北部）的尘埃量。我们使用卫星数据（MODIS 和 CALIPSO）确定了阿拉伯半岛的沙尘暴事件（2015 年 4 月 2 日至 10 日）及其传播到研究地点（果阿）。果阿沙尘暴的影响已使用环境颗粒物浓度和卫星反演的光学参数进行计算。使用地面微脉冲激光雷达测量进一步证实了这些观察结果。日平均激光雷达剖面显示相对较高的去极化率（0.1-0.25），以及较高的日平均反向散射系数（高达 0.08 Sr-1 Km-1）和风暴期间消光系数（高达 0.9 Km-1）与没有尘土飞扬的日子相比。在此期间，观察到具有明显高线性去极化比的两层（富含非球形颗粒）结构，表明沙尘暴对印度沿海地区的影响。使用 CALIPSO 剖面估计的环境粉尘质量浓度与从大量样品收集中测量的重量质量相当。反向轨迹分析进一步支持了气团从中东到阿拉伯海东部的平流。