• Subimal Ghosh

Articles written in Journal of Earth System Science

• Spatio-temporal analysis of sub-hourly rainfall over Mumbai, India: Is statistical forecasting futile?

Mumbai, the commercial and financial capital of India, experiences incessant annual rain episodes, mainly attributable to erratic rainfall pattern during monsoons and urban heat-island effect due to escalating urbanization, leading to increasing vulnerability to frequent flooding. After the infamous episode of 2005 Mumbai torrential rains when only two rain gauging stations existed, the governing civic body, the Municipal Corporation of Greater Mumbai (MCGM) came forward with an initiative to install 26 automatic weather stations (AWS) in June 2006 (MCGM 2007), which later increased to 60 AWS. A comprehensive statistical analysis to understand the spatio-temporal pattern of rainfall over Mumbai or any other coastal city in India has never been attempted earlier. In the current study, a thorough analysis of available rainfall data for 2006–2014 from these stations was performed; the 2013–2014 subhourly data from 26 AWS was found useful for further analyses due to their consistency and continuity. Correlogram cloud indicated no pattern of significant correlation when we considered the closest to the farthest gauging station from the base station; this impression was also supported by the semivariogram plots. Gini index values, a statistical measure of temporal non-uniformity, were found above 0.8 in visible majority showing an increasing trend in most gauging stations; this sufficiently led us to conclude that inconsistency in daily rainfall was gradually increasing with progress in monsoon. Interestingly, night rainfall was lesser compared to daytime rainfall. The pattern-less high spatio-temporal variation observed in Mumbai rainfall data signifies the futility of independently applying advanced statistical techniques, and thus calls for simultaneous inclusion of physics-centred models such as different meso-scale numerical weather prediction systems, particularly the Weather Research and Forecasting (WRF) model.

• Thinking about water and air to attain Sustainable Development Goals during times of COVID-19 Pandemic

In 2020, we are in the doorstep of a new decade, during which the UN Sustainable Development Goals (SDG) are to be achieved, collectively as one nation and one human-hood, where availability of safe, sustainable and clean water and air forms the core of multiple goals. However, the emergence of the COVID-19 pandemic across the globe has resulted a newer challenge and paradigm for an evolving socio-scientific priorities. It is generally expected that the impacts of the pandemic would be in shorter time-scale, while the planned time and pathway for attaining the SDG are typically mandated in longer-term, hence may remain mostly unaffected. However, the stringent lockdown measures, isolated economies and financial burden to contain the pandemic emergency have resulted to slowdown of socio-economic development, which if continues for a longer period, would put a question mark on developing plans and pathways to achieve the SDGs, even in decadal-scale. Hence, in these newer times, it is important to understand the real priorities of availability of clean water and air, which are already stressed worldwide and in India, because of various natural and human-influenced triggers. This ongoing pandemic has provided an unprecedented opportunity to evaluate the impact of human development and consequent feedback of nature and human society in pre- and post-COVID scenarios on water–air–human life, which can help to re-think and re-orient the societal development priorities. It is a rare opportunity for scientists to impress the policy-makers with real-time examples on the efficacies of potential mitigation strategies for climate change, water and air pollution, and the importance of enduring investment on environmental causes and consequent benefits that can secure health and development for our future generations.

$\bf{Highlights}$

$\bullet$ Environmental pollution and climate change pose a high risk for human survival.

$\bullet$ Develop resilience to attain SDGs in spite of economic constraints caused by COVID-19.

$\bullet$ Set real priorities of availability of clean water and air for future, in a unified world.

• # Journal of Earth System Science

Volume 131, 2022
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019