An alarming study recently published in Nature reveals that the rapid melting of Antarctic ice is significantly slowing down ocean overturning circulation. This could yield catastrophic effects on the global climate, marine food chain, and stability of ice shelves.
Overview of the Study’s Key Highlights
The study underlines various severe repercussions from the rapid melting of Antarctic ice.
The Effect on World’s Oceans
With rising temperatures, the freshwater from Antarctica’s melting ice reduces the salinity and density of the surface water. Consequently, this diminishes the downward flow to the sea’s bottom. The research signifies that warm water intrusions in the western Antarctic ice shelf are expected to increase, potentially prompting further melting. It also suggests that deepwater circulation in the Antarctic could weaken at a double rate of the decline in the North Atlantic, with flows from Antarctica potentially dropping by 40% by 2050.
Impact on the Global Climate
The research also indicates that as the upper layers of the ocean become more stratified, they may not absorb as much CO2, leading to higher amounts of carbon dioxide in the atmosphere.
Impact on the Food Chain
Ocean overturning circulation allows nutrients to rise from the bottom, supporting about three-quarters of global phytoplankton production – the base of the food chain. A slowdown in whole circulation will likely decrease the nutrient return from the deep ocean to the surface.
India’s Noteworthy Initiatives in the Context of Antarctica
India officially joined the Antarctic Treaty System on August 1, 1983, becoming the fifteenth Consultative Member of the Antarctic Treaty. India has since established several research stations, such as Dakshin Gangotri, Maitri, and Bharti, to carry out comprehensive studies in Antarctica. The National Centre for Antarctic and Ocean Research (NCAOR) was created to manage the country’s research activities in Polar and Southern Ocean realms. India also passed the Indian Antarctic Act 2022 to regulate visitations, activities, and potential disputes in Antarctica.
Global Deglaciation Impacts
Deglaciation is not restricted to Antarctica; it’s a global issue with alarming impacts on water levels worldwide.
The Thwaites Glacier in Antarctica, already contributing 4% to the global sea-level rise each year, potentially holds enough water to raise sea levels by more than half a meter. The ice cap on Africa’s highest peak, Mount Kilimanjaro, expected to melt by 2050 due to climate change, has already seen an 80% reduction since 1912. Furthermore, Himalayan glaciers have been receding faster than anywhere else globally, losing over a vertical foot and half of ice each year since 2000.
Understanding the Distribution of Water on Earth
An interesting question arises when considering the distribution of water on Earth as it pertains to rivers, lakes, polar ice caps, and glaciers. Unlike common assumptions, the volume of water in polar ice caps and glaciers surpasses the amount in groundwater. However, astonishingly, the quantity of groundwater considerably exceeds that in rivers and lakes. This discrepancy highlights the critical importance of preserving polar ice caps and glaciers given their significant role in the Earth’s water distribution.