Study led by IIT prof shows rapid melting of West Antarctic ice shelves
Times of India | 27 March 2025
123 Kharagpur: New research on climate change published in ‘Communications Earth & Environment' — a peer-reviewed, open-access, scientific journal in Earth science, environmental science and planetary science — has shown rapid melting in the ice shelves in West Antarctica in recent decades.
Led by Prof Pranab Deb from IIT Kharagpur's Centre for Ocean, River, Atmosphere and Land Sciences, and David Bromwich from the Byrd Center's Polar Meteorology Group, the study provides new insights into atmospheric factors affecting Antarctic ice conditions.
The research analyses two time frames (1979-1998 and 1999-2018) using satellite information and regional climate models. The first period showed declining melt patterns, whilst the second period demonstrated increased melting across major ice shelves in the Ross-Amundsen Sea sector.
The study attributes the shift of ‘Interdecadal Pacific Oscillation', a climate pattern that causes the Pacific Ocean to warm or cool over decades, to the increased melting in the late 1990s. This factor warmed the ocean water in the South Pacific Convergence Zone (SPCZ) located east of Australia and New Zealand.
"The warm ocean surface can drive strong upward motion of air, triggering large-scale atmospheric waves shaped by Earth's rotation, which can influence the climate of far-off areas like Antarctica. The research demonstrates that since the late 1990s, these waves, known as Rossby waves, intensified high-pressure systems over West Antarctica which directed warm marine air towards Antarctic ice shelves, causing surface melting of the ice shelves," said Prof Deb.
The findings from this research have important implications for the stability of the West Antarctic ice sheet and future global sea level rise. Increased strength and frequency of these high-pressure systems and continued warm air transport to West Antarctica could further destabilise ice shelves, which act as natural barriers that prevent massive ice sheets from flowing into the ocean. These could, in turn, accelerate sea-level rise, posing a significant threat to coastal regions worldwide.
For India, with its extensive coastline and densely populated low-lying areas, this risk is particularly concerning. Rising sea levels could lead to coastal erosion, flooding, and loss of livelihoods, underscoring the urgent need to understand and monitor Antarctic ice changes.
"Understanding the complex interactions between tropical convection, atmospheric circulation, and ice shelf stability is vital for accurately predicting the future of Antarctica's ice sheets and their contribution to sea-level rise. This research highlights how even distant tropical influences can significantly impact polar regions," said Bromwich.
The study emphasises improving climate models by including remote tropical influences, particularly from the SPCZ, for better cryospheric predictions. Enhanced models could assist in preparing for the long-term effects of Antarctic ice loss.
Deb led the research, collaborating with Bromwich, Andrew Orr, Arnab Sen and Kyle R Clem.