Melting ice in the Antarctic is causing a rapid slowdown of a major global deep ocean current that could alter the world’s climate, reduce the supply of vital nutrients to marine life, and accelerate sea level rise. A new study, based on two years of research using around 35 million computing hours, has warned that if greenhouse gas emissions continue at their present rate, the circulation of deep ocean water could decline by 40% by 2050. This would reduce the delivery of heat, carbon, oxygen, and vital nutrients around the globe.
Melting ice in Antarctica Slowing Down Deep Ocean Current
The deep ocean current in question originates in the cold, fresh, dense water off Antarctica’s continental shelf. It plays a crucial role in transferring heat from the tropics to Antarctica and then on to the rest of the world’s oceans. The deepwater circulation is also important for sequestering carbon absorbed from the atmosphere. But if it slows down, it would cause deep waters to heat up and stagnate, starving them of oxygen.
Potential Disastrous Impacts if Deep Ocean Current Fails
Worryingly, scientists have warned that this slowdown could potentially end an ocean system that has helped sustain life for thousands of years. With fewer nutrients being returned to upper layers of the ocean, phytoplankton production will be affected. Phytoplankton is at the base of the food chain and supports about three-quarters of global phytoplankton production. This could leave marine ecosystems without this primary food source.
Furthermore, a slowdown in this deep ocean current could lead to further warming at the base of ice shelves around Antarctica, causing more ice melt. Freshwater from melting Antarctic ice reduces salinity and density of surface water which decreases downward flow to its bottom.
No Integration Of Ice Meltwater on Ocean Circulation Accelerating Climate Change
While rising sea levels and other impacts of global warming are urgent concerns, the effect of meltwater from ice sheets on global ocean circulation has not been included in the IPCC’s complex models used to describe future climate change scenarios. This is alarming considering the considerable impacts it will have.
The study warns that if fossil fuels continue to be burned and planet-heating pollution is produced, the Antarctic overturning circulation is on track to slow down by 42% by 2050. This could shift rain bands in the tropics by as much as 1,000 kilometers.
Urgent Need for Change
The findings have implications for humanity, with the IPCC report warning that the impacts of rising global temperatures are more severe than expected. Without immediate and deep changes, the world is hurtling toward increasingly dangerous and irreversible consequences of climate change.
The study is an urgent warning that choices made over the next decade will commit ourselves to a future with reduced nutrient supply for fisheries. Therefore, decisive action must be taken to reduce carbon emissions and limit global warming. The world leaders have been called upon to take this issue seriously and prioritize addressing it in their plans to combat climate change.
Overall, these findings underline the need for immediate and comprehensive measures to combat climate change. Failure to act now will lead to disastrous consequences that will hit all life forms on our planet. The impacts of this crisis are already being felt, and they will become more severe with time if we don’t take corrective action without delay.
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