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Preventing water crises
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Preventing water crises

Corals back from the dead discovered in the Mediterranean Sea

For the first time ever, living polyps were discovered in Mediterranean coral colonies that were previously thought to be completely dead by researchers who published their finding in the periodical Science Advances.

Diego K. Kersting from the Freie Universität Berlin and Cristina Linares from the University of Barcelona have studied 243 colonies of the endangered reef-builder coral Cladocora caespitosa along the Spanish coast of the Mediterranean Sea since 2002.

In their previous papers, the researchers reported mass mortalities caused by recurring marine heat waves.

“At some point, we saw living polyps
in these colonies, which we thought were completely dead,”
Kersting recalled, calling
their discovery a “big surprise”.

Corals are made up of hundreds to thousands of tiny creatures called polyps that secrete a hard outer skeleton of calcium carbonate and attach themselves to the sea floor.

Photo: Phys.org

Marine heat waves kill these animals by either essentially cooking them alive, or by causing them to eject the symbiotic algae that live within them and provide them with nutrients and their characteristic colour, leaving only the whitish limestone structure behind.

An extreme marine heat wave killed almost a quarter of the coral colonies of Spain’s Columbretes Islands in 2003.

But the researchers found that
in 38 percent of the colonies studied,
the polyps have created a survival strategy:
they shrunk, partially abandoned
their original skeletons, and then
grew back in the course of several years, starting new skeletons and
re-colonizing dead areas through a process called budding.

The researchers used 3D computer mapping to prove that the new structures are connected to the old, abandoned skeletons, so it is the same polyps staging a comeback. This process of “rejuvenescence” was known to exist in the fossil record, but this was the first time it was observed in living coral colonies.

Photo: Phys.org

Source: MTI – Hungarian News Agency

Further information: Phys.org

Oceans absorb massive quantities of carbon dioxide

The oceans play a very important role in controlling Earth’s climate. New research has shown that the planet’s five oceans absorb much more carbon dioxide, one of the gases responsible for the greenhouse effect, than previously thought.

Temperatures in Israel increase by 0.25 degrees Celsius per decade

According to a study published in the International Journal of Climatology, Israel’s average temperature has been rising continuously since the proclamation of the Middle Eastern state in 1948, but over the last thirty years the rate of warming has also increased.

Temperatures increase much faster than global average in the Mediterranean region

Temperatures are rising much faster than the global average in the region of the Mediterranean Sea, and this represents a threat to the food and water resources of the region, researchers have warned in a new study.

Fates, faces, contrasts

The news about climate refugees are alternating sequences of frightening numbers and apocalyptic landscapes that obscure the real face of the problem: the disfigured human fates.

Climate change causing great damage to UK wildlife

More than a quarter of all mammals are threatened with extinction.

Several hundred temperature records broken in 2019

Between 1 May and 30 August, higher than ever temperatures have been measured in 29 countries, on almost 400 occasions in the Northern Hemisphere.

The perishing glaciers of the Alps – shown from a special perspective

The French falconer Jacques-Olivier Travers has surveyed the glaciers of the Alps using a camera attached to a white-tailed eagle.

The Polarstern sets off on a unique expedition frozen to an ice floe

The ice floe that the German research boat will be attached to as it drifts around the Arctic for almost a year on the most important Arctic expedition ever has been selected.

September 2019 the warmest so far

Data from European climate researchers indicates that this year’s was the warmest September since the Copernicus Climate Change Service began keeping regular records of meteorological data in 1981.

Oceans are warming at an alarming rate

If the current trend continues, oceanic wildlife is in grave danger.

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