CORAL, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
CORAL, Indian Institute of Technology Kharagpur, Kharagpur 721302, India.
Sci Total Environ. 2022 Sep 10;838(Pt 1):155885. doi: 10.1016/j.scitotenv.2022.155885. Epub 2022 May 17.
The increase in greenhouse gases (GHGs) due to anthropogenic activities enhances regional and global temperatures. The most abundant GHG, i.e., water vapour, has a vital positive feedback on the global warming and Earth's climate system. This study focuses on the spatial and temporal changes in water vapour in the troposphere over India and Indian Ocean as derived from the ground-based, satellite and reanalyses data, and assesses the impact on water vapour changes on the regional climate by analysing radiative effects. The analyses show that the annual mean column water vapour (CWV) is high over the northern Indian Ocean, Bay of Bengal and Peninsular India, ranging from 30 to 60 kg/m. Most regions show significant positive trends in the annual mean CWV, about 0.1-0.2 kg/m/yr. There is a significant positive trend in water vapour in the troposphere (except 200 hPa) over the India land regions, with the highest values at 1000 hPa (0.034 g/kg/yr). The corresponding water vapour radiative effect (WVRE) is about 20-80 W/m, depending on seasons and regions. This study, therefore, indicates that the increase in tropospheric water vapour over India and Indian Ocean could affect the regional temperature and climate.
由于人为活动导致温室气体（GHGs）增加，从而提高了区域和全球温度。最丰富的温室气体，即水蒸气，对全球变暖及地球气候系统具有重要的正反馈作用。本研究重点关注从地面、卫星和再分析数据中得出的印度和印度洋对流层中水蒸气的时空变化，并通过分析辐射效应来评估水蒸气变化对区域气候的影响。分析表明，北印度洋、孟加拉湾和印度半岛北部的年平均柱水汽（CWV）较高，范围在 30 到 60 千克/米之间。大多数地区的年平均 CWV 呈显著正趋势，约为 0.1-0.2 千克/米/年。印度陆地地区的对流层（200 hPa 除外）中水蒸气呈显著正趋势，在 1000 hPa 处的数值最高（0.034 g/kg/yr）。相应的水蒸气辐射效应（WVRE）约为 20-80 W/m，具体取决于季节和地区。因此，本研究表明，印度和印度洋对流层中水蒸气的增加可能会影响区域温度和气候。
