Nyelvváltás
Preventing water crises
Küldés e-mailben Facebook Twitter Nyelvváltás
Preventing water crises

Dropping oxygen levels of the oceans to cause ecological crisis

It is a lesser known fact that climate change is also making the oxygen levels of the oceans drop. Over the last 50 years, the average oxygen content of the world’s oceans has dropped by almost 2%, which may have dramatic consequences.

Today, the area of oceanic zones with insufficient oxygen to sustain life are growing. Something similar occurred 420 million years ago, during the so-called Lau/Kozlowskii extinction event: 23% of marine life forms went extinct due to the reduced level of oxygen.

The Lau/Kozlowskii extinction event is a long-standing subject of dispute among scientists, as it was not associated with any specific occurrence such as a massive volcanic eruption or meteor impact. Researchers at Florida State University (FSU) believed it was particularly important to study that extinction because a similar global decline in biodiversity is taking place today, so the research may shed light on the potential outcomes of various present climate scenarios.

The researchers at FSU measured the quantity of thallium and sulphur isotopes and the concentration of manganese in sediment samples collected in Lithuania and Sweden, and used the data to establish a precise timeline of the decline in oceanic oxygen levels.

The research has established a clear link between mass extinction and the drop in oxygen levels. During the event, deep sea creatures died out first, then oxygen was depleted in shallower waters too, and the concentration of sulphurous compounds also grew to make the oceans even less habitable.

The link between the extinction 420 million years ago and the lack of oxygen in the water paints a bleak picture of the future: the recent, relatively fast 2% drop in the oxygen level of the oceans foreshadows an ecological crisis.

Lack of oxygen represents severe stress for living organisms, so we must not disregard this consequence of climate change Photo: Shutterstock
Further information: Florida State University

The ocean is too hot

From Alaska to California, the temperature of the Pacific Ocean is well above average.

Prague saying goodbye to a record hot summer

Since measurements began in Czechia almost two and a half centuries ago, there has not been a summer as hot as this year’s in Prague, when daily average temperatures reached 22.9 degrees Celsius.

UN High Commissioner: the world is in an alarming state

In her opening address at the 42nd Regular Session of the UN Human Rights Council, Michelle Bachelet, UN High Commissioner for Human Rights, expressed grave concern about the condition of the global environment.

Proposal to introduce the siesta in Germany due to climate change

Climate change is making Germany’s climate warmer, with a series of new high temperature records and heat waves making people’s lives more difficult. In response to the changes, the German Trade Union Confederation has proposed introducing the siesta break to protect workers.

Britain’s birds suffer the impact of climate change

Climate change will have a long-term effect on the future of a third of the bird species studied.

Russia is warming up at over twice the average rate

The country’s average temperature has increased by 0.47 degrees Celsius each decade since 1976.

Future is bleak for European skiing industry

The European skiing industry has to reckon with much less snow and much shorter seasons as a result of climate change. Skiing resorts are responding to the challenge by using snow cannons and employing innovative snow production technologies – a practice that environmentalists believe to be particularly harmful.

Climate change presents new challenges for healthcare

A study by researchers at the University of Colorado claims that along with new types of psychological problems such as climate anxiety and ecological grief, climate change has many other unfavourable consequences for human health, such as the chronic kidney disease that is becoming increasingly common among agricultural workers.

Forecasts have proven too optimistic

Europe is warming up faster than expected, with climate change increasing the number of extremely hot days while reducing the number of extremely cold ones, reported researchers at ETH Zürich University in their study published in the journal of the American Geophysical Union, the Geophysical Research Letters.

New islands discovered in the Arctic Ocean – after a glacier melted

The hydrography research group of the Russian Navy’s Northern Fleet has discovered five islands in the region of Franz Josef Land in the Arctic Ocean, the website of the Russian news agency RIA Novosti reported.

1
2
3
4
5