Climate Change

Due to climate change, the average temperature in the Mediterranean Sea rises by one degree every thirty years, and this rate has been increasing. Because of this, the marine creatures there have been shifting their habitats to the deeper, cooler depths of the ocean.

Researchers reached this conclusion after reviewing research involving the depth distribution of 236 marine species like fish, crustaceans and mollusks collected in previous bottom-trawl surveys.

Corals are able to respond to changes in their environment through acclimation (the physiological process of becoming accustomed to a new condition) and adaptation and researchers believe natural populations may already be adapting to increasing sea surface temperatures.

Ocean warming is causing declines of coral reefs globally, raising critical questions about the potential for corals to adapt. In the central equatorial Pacific, reefs persisting through recurrent El Niño heatwaves hold further important clues; We have previously reported on Red Sea coral resilience to climate change.

On 20 February 2016, tropical cyclone Winston struck Fiji. It was described as the most destructive cyclone ever to strike in the Pacific. With winds of up to 280km/h, the coral reefs in the Namena Marine Reserve and Vatu-i-Ra Conservation Park off Fiji were completely destroyed.

To understand how cyclones affect coral reefs and how fast the reefs recover, the team at Wildlife Conservation Society (WCS) Fiji conducted three surveys at different times—one month after, six months after and in December 2020 (more than four years after the cyclone).

Researchers at Michigan State University and the University of Hawaii at Manoa have been uncovering clues as to why some corals bleach while others are resistant, information that could help reefs better weather warming waters in the future.

The team analysed the biochemistry of corals using mass spectrometers to understand what set resistant corals apart from susceptible ones. The scientists found that two different communities of algae lived within the corals. Inside the algae cells were compounds known as lipids.

Researchers conclude the northward range shift demonstrates water temperatures within their preferred temperature range of juvenile white sharks are becoming harder to find.

The animals have historically remained in warmer waters in the southern California Current; Between 1982 and 2013, the northernmost edge of the juveniles' range was located near Santa Barbara (34° N).

Atolls are often only around two meters (6.6 feet) above sea level, but sea levels could rise by more than that by the end of this century, according to prevailing climate models. Four atoll nations -- the Marshall Islands, Tuvalu, Kiribati, and the Maldives, which are together home to more than half a million people -- were the most vulnerable on the planet to climate change but under threat was also those in the Caroline Islands, Cook Islands, Gilbert Islands, Line Islands, Society Islands, Spratly Islands, Seychelles, and Northwestern Hawaiian Islands.

Coral reefs have been seeking new pastures, as rising temperatures heat up their natural habitats.

Over the last four decades, coral reefs have been progressively shifting their homes from equatorial waters to more temperate regions.

The reason? Climate change.

“Climate change seems to be redistributing coral reefs, the same way it is shifting many other marine species,” said Nichole Price, a senior research scientist at Bigelow Laboratory for Ocean Sciences and lead author of the paper on the topic.