The mysterious mesopelagic Twilight Zone harbors a plethora of marine creatures. From mesmerizing jellyfish to elusive viperfish and lanternfish, this zone is a bustling ecosystem filled with life forms like larvaceans, copepods, and squids. Credit: Wikimedia/Drazen et al, CC BY-NC-ND
While we often hear about heat waves and cold snaps on land, the deep sea also undergoes prolonged periods of extreme temperatures.
These marine temperature fluctuations can have devastating effects on ocean ecosystems such as coral reefs. They can lead to species displacement or mortality and result in sudden declines in fish populations.
A recent study published in Nature reveals that nearly half of the heat waves and cold spells affecting the ocean’s twilight zone—ranging from 200 to 1,000 meters deep—are driven by powerful eddy currents that transport warm or cold water.
With oceans warming up due to climate change, eddy-driven heat waves are becoming more severe along with cold snaps. These phenomena pose significant risks to the abundant life within the twilight zone—the habitat of countless vertebrates and home to one of Earth’s largest migrations.
Approximately 90% of the excess heat trapped by greenhouse gases ends up in our oceans. Consequently, marine heat waves are becoming more frequent in regions like Australia’s east coast, Tasmania, northeast Pacific coast of the US, and North Atlantic.
Traditionally relying on satellite data for surface temperature measurements to monitor extreme ocean temperature events may not be sufficient for detecting these occurrences at depth where atmospheric influence is minimal.
2024-10-20 03:15:02
Source from phys.org