Ocean Hotspots Forming Fast: Chain Reaction Started with Climate Change, Scientists Prove

By looking at the winds that affect the ocean currents heating these areas, University of New South Wales (UNSW) researchers have found the answer to the question of why and how ocean hotspots are forming so quickly. Later analysis shows that the chain reaction is started by climate change.

Southern Hemisphere western boundary currents are rapidly warming, according to researchers from UNSW Sydney, and this is changing weather and habitats all over the world. The change is attributed to changes in strength and large-scale wind patterns.

Large amounts of heat are carried to the poles by the ocean's western boundary currents, which include the East Australian Current. These currents play a key role in regulating coastal climates around the world. They have created ocean "hotspots" by warming their poleward extension regions two to three times faster than the global average over the last few decades, but back then, no one understood why.

Mystery Solved

Researchers from the School of Biological, Earth, and Environmental Sciences at UNSW Sydney solved the mystery of global warming in their study.

Dr. Junde Li, the lead author of the study, said that the easterly winds at mid-latitudes are shifting south due to climate change, which is what is causing the rapid warming.

Li said this was resulting in more eddies, which are sizable ocean whirlpools that trap and carry warm ocean waters, in the western boundary current poleward extensions.

These modifications are causing heat, dissolved gases, and nutrients to be redistributed globally, which is altering regional weather patterns and marine ecosystems.

The livelihoods and lives of hundreds of millions of individuals who live along the coasts of South Africa, Australia, and Brazil are impacted by the western boundary currents found in the Southern Hemisphere.

Professor Moninya Roughan, a co-author of the study, said that Southeast Australian ocean temperatures are rising rapidly. This warming trend is occasionally broken by periods of extreme warmth. For example, in February 2022, all Sydney coastal water heat records were broken.

Global Warming and Wildlife

According to Roughan, ocean hotspots stress coastal lifeforms, which can cause a permanent loss of habitat. Along the east coast, the warming has extended further south, bringing many species with it.

This includes sea urchins migrating to Tasmanian offshore waters. The invasion of warmer water as well as the kelp-eating urchins in this area both contributed to the destruction of kelp forests. Both the local tourism and crayfish industries were impacted by this.

Li said that despite the study's emphasis on the Southern Hemisphere, the findings may also shed light on the factors that contribute to ocean warming as well as marine heat waves in the western boundary currents of the Northern Hemisphere, such as the Gulf Stream.

Li added that as the atmosphere warms, the oceans will also continue to get warmer. As a result, high-resolution datasets must be created to better comprehend the dynamic behavior of global heat transport.

This can aid in the forecasting and planning for the effects of warming on local communities, industries, and much more as a result of climate change, Phys Org reports.