Recent research has uncovered a concerning trend in the frequency of extreme rainfall events over the Meghalaya plateau and surrounding areas, including parts of Northeast India and Bangladesh. The study, published in the Journal of Royal Meteorological Society, spans the period from 1950 to 2021 and highlights a fourfold surge in extreme rainfall incidents, defined as those exceeding 15 cm per day.
Traditionally recognized for its high rainfall, Meghalaya, home to Cherrapunji and Mawsynram (among the wettest places globally), has witnessed a shift in precipitation patterns. Notably, the Indian Meteorological Department’s data indicates a decreasing trend in monsoon rain over the northeastern region, contrary to the observed increase in extreme rainfall events.
The research, co-authored by Roxy Mathew Koll, sheds light on the complex interplay of factors contributing to this phenomenon. The study involved scientists from esteemed institutions such as NASA Goddard Space Flight Center, North Carolina State University’s Department of Marine, Earth and Atmospheric Science, and the Indian Institute of Tropical Meteorology’s Centre for Climate Change Research.
According to the findings, the intensified lower tropospheric moisture transport and flux through monsoon flow, driven by warm Bay of Bengal sea-surface temperatures, are key contributors to the increased extreme rainfall. These conditions converge over inland areas, particularly in Meghalaya and Bangladesh, resulting in heightened precipitation during extreme events.
Despite an overall decreasing trend in total rainfall in these regions, the research emphasizes the alarming rise in the intensity of extreme rains. The consequences of such events, including flash floods and landslides, pose a significant threat, especially given the geographical vulnerability of Northeast India and Bangladesh to flooding.
Looking ahead, the research indicates that this upward trend in extreme rainfall events is projected to continue in the future, with potential implications for flooding and associated disasters. The study advocates for long-term preparedness measures, suggesting the identification of vulnerable hotspots and the implementation of flood-proofing strategies for districts prone to extreme rains and landslides.
In summary, the research underscores the urgency of addressing the challenges posed by climate change-induced extreme rainfall in these regions, emphasizing the need for adaptive strategies and improved warning systems to mitigate the impact on densely populated areas in Bangladesh and India.