According to an updated report on the global ocean released by the European Union's Copernicus Marine Environment Monitoring Center on the 22nd, the range of Arctic ice recorded in the past two years has reached an all-time low, with an average decline of nearly 13% per decade since 1979 to 2020, and its sea ice reduction is equivalent to 6 times the area of Germany.
The annual Copernican Marine Environment Monitoring Centre Ocean Status Report 5, published in the peer-reviewed Journal of Operational Oceanography, draws on analysis by more than 120 scientists from more than 30 European institutions and is a comprehensive, advanced scientific report on the current state, natural changes and ongoing changes in the global oceans and the European region.
Image source: Visual China
The report shows that the oceans are undergoing unprecedented changes, which have a huge impact on human well-being and the marine environment. Surface and subsurface sea temperatures are rising around the world, and warming oceans and melting land ice are causing sea levels to continue to rise at an alarming rate: 2.5 millimetres per year in the Mediterranean and 3.1 millimeters per year globally.
It is estimated that warming in the Arctic Ocean accounts for nearly 4% of total global ocean warming. The average sea ice thickness of the Barents Sea (a small part of the Arctic) has decreased by almost 90 percent, which has led to a decrease in sea ice imports from the polar basin.
The report argues that in the North Sea, extreme changes in cold waves and marine heat waves are associated with changes in the catch of flounder, European lobster, sea bass, red mullet and edible crabs. Pollution from land-based activities such as agriculture and industry is leading to ocean eutrophication, affecting fragile ecosystems.
The report also shows that ocean warming and increased salinity in the Mediterranean have intensified over the past decade. In the Mediterranean, Venice had 4 consecutive record flood events (November 2019) and the southern Mediterranean had above-average wave heights (2019).
From 1993 to 2019, the global average SST rose at a rate of 0.015 degrees Celsius per year, and from 1955 to 2019, oxygen levels (oxygen stocks) in the Black Sea declined at a rate of 0.16 moles/m2/year.
Dr Karina von Schuchmann, head of the report, concluded that climate change, pollution and overexploitation are putting unprecedented pressure on the oceans, which not only account for 71% of the Earth's surface, but also play an important role in regulating the Earth's climate and sustaining life. We urgently need sustainable governance, adaptation and management measures to ensure that the oceans and seas provide a full range of life-supporting roles for human well-being. "Embracing the ocean as an essential element of the Earth system, embracing the multidimensional and interconnected nature of the ocean, is the cornerstone of a sustainable future," Schuchman said. ”
Source: Science and Technology Daily