Abstract

The novel infectious disease (COVID-19) took only a few weeks from its official inception in December 2019 to become a global pandemic in early 2020. Countries across the world went to lockdown, and various strict measures were implemented to reduce the further spread of the infection. Although, the strict lockdown measures were aimed at stopping the spread of COVID-19, however, Its positive implications were also observed for the environmental conditions across the global regions. The present study attempted to explore the eco-restoration of coastal marine system in response to reduced deposition of atmospheric nitrogen (NO₂) emission during the substantial shift in human activities across the global metropolitan cities. Remotely data of NO₂ emission were taken from Ozone Monitoring Instrument and the coastal water quality along the marine system was estimated from MODIS-Aqua Level-3 using Semi-Analytic Sediment Model (SASM). The changes in tropospheric NO₂ in 2020s were also compared with the long-term average changes over the baseline period 2015 − 2019. A significant reduction in anthropogenic mobility (85 − 90%) has been observed in almost all countries over different places, especially grocery, parks, workplaces, and transit stations. A massive reduction in tropospheric NO₂ was detected in Wuhan (53%), Berlin (42%), London (41%), Karachi (40%), Paris (38%), Santiago (35%), and Chennai (34%) during the strict lockdown period of the early 2020 as compared to the last five years. However, after the partial lockdown was lifted, tropospheric NO₂ values bounced back and slightly increased over Karachi (6%) and Bremen (12%). For water turbidity, the rate of reduction was found to be the highest along the different coastal regions of the Mediterranean Sea and Black Sea (51%), West Atlantic Ocean (32%), East Atlantic Ocean (29%), and Indian Ocean (21%) from Apr to Jun 2020. The monthly comparison of overland-runoff in 2020 compared to 2019 across the different costal watersheds indicates that the observed decline in turbidity might have been due to the reduced deposition of atmospheric nitrogen. The findings of this study suggest that the recent decline in tropospheric NO₂ and water turbidity might be associated with reduced emissions from fossil fuels and road transports followed by COVID-19 forced restrictions in the twenty-first century. The inferences made here highlight the hope of improving the global environmental quality by reducing greenhouse gas emissions using innovative periodic confinement measures on heavy transport and industries while securing public health and socioeconomics.

摘要

新型传染病（COVID-19）从 2019 年 12 月正式爆发仅用了几周时间，就在 2020 年初成为全球大流行病。世界各国纷纷采取封锁措施，并采取了各种严格措施，以减少疫情的进一步蔓延。感染。尽管严格的封锁措施旨在阻止 COVID-19 的传播，但是，也观察到了其对全球地区环境条件的积极影响。本研究试图探索沿海海洋系统的生态恢复，以应对全球大都市人类活动发生重大转变期间大气氮 (NO ₂ ) 排放量减少的情况。NO ₂遥测数据排放来自臭氧监测仪器，沿海洋系统的沿海水质使用半分析沉积物模型 (SASM) 从 MODIS-Aqua Level-3 估计。还比较了 2020 年代对流层 NO ₂的变化与2015-2019 年基线期的长期平均变化。几乎所有国家的不同地方都观察到了人为流动性的显着降低（85-90%），尤其是杂货店、公园、工作场所和中转站。在对流层NO大幅减少₂在严格封锁期间，在武汉（53%）、柏林（42%）、伦敦（41%）、卡拉奇（40%）、巴黎（38%）、圣地亚哥（35%）和钦奈（34%）被发现2020 年初与过去五年相比。然而，在解除部分封锁后，对流层 NO ₂价值反弹并略高于卡拉奇 (6%) 和不来梅 (12%)。对于水浊度，发现地中海和黑海（51%）、西大西洋（32%）、东大西洋（29%）和印度洋的不同沿海地区的降低率最高(21%) 从 4 月到 2020 年 6 月。 2020 年与 2019 年不同沿海流域的陆上径流月度比较表明，观察到的浊度下降可能是由于大气氮沉积减少。这项研究的结果表明，最近对流层 NO _{2 的}下降水浑浊可能与化石燃料和公路运输的排放减少有关，随后是 21 世纪 COVID-19 强制限制。这里的推论强调了通过对重型运输和工业采取创新的定期限制措施来减少温室气体排放，同时确保公共卫生和社会经济，从而改善全球环境质量的希望。