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Earth “derailed”

According to the AP news agency, more than 90% of the coral in the Great Barrier Reef – coral reef ecosystem largest in the world – bleached in the 4th mass bleaching in just 7 years.

Ocean “amnesia”

More ominously, this is the first time the reef has bleached during the La Niña cycle. Coral bleaching occurs when the planet is warmed while La Niña is the cooling phase of the planet.

That’s not the only paradox. According to a study just published in the scientific journal PNAS, the earth continuously oscillates between 2 states “hot house” and “bank house”. We are in the middle of an “ice house”, a period of global cooling that has been indicated since the 1970s.

However, the fact that people greenhouse gas emissions are massively reversing this natural trend at an unprecedented rate. Not to mention, the wildfires that are happening everywhere – from New Mexico in the US to Siberia in Russia – will create another worrying carbon “bomb”.

Earth derails - Photo 1.

A diver is approaching the world’s largest coral reef Great Barrier Reef Photo: AP

That happened once in the history of the earth: At the Kasimovian – Gzhelian boundary of the Pennsylvanian, Carboniferous period, more than 303 million years ago. At this time there was a mass extinction. Carbon in ozone doubled in 300,000 years.

The ice melts too quickly, pushing fresh water into the ocean surface, hindering oxygen in the atmosphere from dissolving and circulating in the sea, leaving 23% of the sea floor lacking oxygen. “The release of large volumes of carbon coupled with abrupt warming will promote ocean deoxygenation and extinctions,” the study quoted Science Alert as saying.

Oceanic climates are also “derailed” on a large scale, which scientists call the ocean phenomenon “amnesia”. “We find that oceanic memory, as measured by the annual persistence of sea surface temperature anomalies, is expected to decline gradually over the coming decades across much of the world,” said the gas researcher. Hui Shi from the Farallon Institute in Petaluma, California (USA), first author of a study, just published in Science Advances, said.

They looked at surface temperatures in the ocean’s upper mixed layer (MLD), which is water from the surface to a depth of about 50 meters. This layer of water exhibits the persistence over time of thermal inertia. However, this thermal inertia is decreasing, the MLD is more susceptible to random temperature anomalies, reducing its ability to provide marine life with a stable habitat.

An ominous forecast for a very hot year

Ocean “amnesia” is also reflected in climate fluctuations becoming erratic, losing periodicity, making human forecasting systems about ocean temperature, precipitation, monsoon, marine heat wave and natural disasters… no longer accurate.

Meanwhile, in the 2015 Paris Agreement on climate change, countries agreed to limit global warming to no more than 2 degrees Celsius, preferably no more than 1.5 degrees Celsius compared to the previous period. pre-industrial (1850-1900). But the World Meteorological Organization (WMO) has just forecasted that in the period 2022-2026, the risk of at least 1 year breaching the 1.5 degrees Celsius limit is 48%.

“The number 1.5 degrees Celsius is not a random statistic. It is an alarming point as climate impacts will become increasingly harmful to people and the entire planet” – WMO Director Peter Taalas said. However, Mr. Taalas is also optimistic that with today’s level of science, the Paris Agreement can still be kept if people make efforts.

The AP news agency cited independent commentary by climate scientist Zeke Hausfather from Stripe Technology and Berkeley Earth, who said that with La Niña – in its second year – still succumbing to warming caused by By human burning of coal, oil and natural gas, worse warming will occur when El Niño returns – the end of 2023, when the La Niña cycle ends.

In addition, models predicting rainfall in 2022 show that the risk of drought will cover parts of southwestern Europe, southwestern North America and vice versa, leaving Northern Europe, the Sahel region in Africa, and northeastern Brazil and Australia is too wet, which means there is a risk of being submerged in floods.

Canaries in the coal mine

Research just published in the Annual Review of Environment and Resources warns that 48% of the world’s bird species are in decline. “We are witnessing the first signs of a new wave of bird extinctions,” said conservation biologist Alexandre Lees from Manchester Metropolian University (UK), lead author, said.

Statistics for 2019 show that the number of birds in North America has decreased by nearly 3 billion compared to 1970. Similar fates befall millions of other birds in Europe, according to the 2021 census. At least half of the bird species in the South Africa is losing its habitat and dying. Many species are on the brink of extinction. The cause is still climate change. This threatens the ecosystem back, because birds are the main pollinators of plants.

Not to mention, birds are the alarm bells of the earth. Science Alert likens it to the “canary in a coal mine” effect. Miners in the past used to bring along a canary, which is extremely sensitive to toxic elements in the environment. When the canary died unexpectedly, they had to quickly get out of the beak to save their lives.

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