Revealing the oceanic climate code is particularly important now

World Meteorological Day, experts call for——

Revealing the oceanic climate code is particularly important now

From a bird's-eye view of the vast universe, the Earth has a deep blue color, which is the color of the ocean that accounts for more than 70% of its surface area.

The ocean is a source of wind and rain, a huge "regulator", and is crucial for stabilizing the climate. However, according to a recent climate statement issued by the World Meteorological Organization, 2020 is one of the three warmest years on meteorological records.

March 23rd is World Meteorological Day. "This year's theme is' Oceans, Our Climate, and Weather ', which aims to call attention to the relationship between weather, climate change, and the oceans." Zhou Bing, the chief expert on climate services at the National Climate Center, said in an interview with a reporter from Science and Technology Daily.

Oceans are closely related to climate

"The ocean is closely related to our weather and climate change. There is an exchange of heat, momentum, and matter between the ocean and the atmosphere. The interaction between the ocean and the atmosphere can cause ever-changing weather and climate phenomena or extreme events, such as El Nino events, La Nina events, and typhoons, leading to global or regional climate anomalies and meteorological disasters," Zhou Bing said.

Zhou Bing said that the ocean plays a very important role in atmospheric movement and climate change. The movement of ocean currents within the ocean and the thermal difference between land and sea have shaped diverse natural landscapes and complex and diverse weather and climate phenomena on the planet. For example, the North Atlantic Warm Current has brought beautiful ecological environments to some northern European countries, while the East Asian monsoon climate and the South Asian monsoon climate have brought favorable weather conditions to agricultural production in Asian countries.

According to Su Jingzhi, a researcher at the Chinese Academy of Meteorological Sciences, the ocean plays a very important regulatory role in the global weather and climate system. It can regulate the weather and climate conditions of the Earth, such as temperature and humidity. Due to the relatively large thermal inertia of the ocean, the capacity of seawater of the same volume to store heat is more than 2000 times that of the atmosphere. If there were no oceans, the temperature difference between day and night, winter, and summer on Earth would be large, and the fluctuations in temperature would also be very severe, making it possible for humans to not adapt to living.

According to data, the ocean contributes 90% of the earth's rainfall and also absorbs 90% of the earth's excess heat. The ocean currents redistribute the heat to various parts of the world, preventing the earth from getting hot or cold all the time.

"The ocean also provides a large amount of water vapor to the atmosphere, which makes the air we breathe more humid, otherwise the earth would not be suitable for human habitation," Su Jingzhi said.

The ocean is still warming

"Observed facts indicate that the Earth's climate system is currently in a very fragile balance," Zhou Bing said.

Statistics show that over the past 100 years, nearly 50% of coastal wetlands have been lost due to the combined effects of sea level rise, climate warming, and extreme weather events. Since the 1980s, the ocean has absorbed 20% to 30% of the carbon dioxide emitted by humans, leading to continued acidification of the ocean. Due to the increasing rate of ice loss in the Greenland and Antarctic ice sheets, sustained loss of glacier mass, and ocean thermal expansion, sea level rise has accelerated in recent decades.

"Especially in 2020, although the global carbon emissions decreased slightly due to the global COVID-19 epidemic, the data shows that the global greenhouse gas emissions will increase in 2020, the global ocean will continue to warm up, and the ocean heat will reach a new high." Zhou Bing is very sad about this.

What worries him even more is that in the future, abnormal sea level rises in more regions will be more frequent, and increasingly frequent high water levels will have a serious impact on many regions. As the ocean warms and sea ice decreases, the global biomass, production, and fishing potential of marine animal communities will decrease, and species composition will also change; The risk of adverse impacts such as inundation, coastal flooding, and coastal erosion in coastal and low-lying areas will increase.

Speaking of these, Su Jingzhi very much agrees. He said that the ocean has been continuously warming in recent decades, and extends from the ocean surface to over 2000 meters below the sea floor. In recent years, the frequency of ocean heat waves has increased significantly, with seawater temperatures even rising by around 4 ℃ and lasting for more than a few months. "The sea water temperature originally had a small range of change, with a significant fluctuation of one or two degrees. Such a high temperature rise has a significant impact on the survival of marine ecology, fish, and algae." Su Jingzhi said.

"It is particularly important to point out that the oceans now store a large amount of excess heat, with a depth of over 2000 meters. After decades or hundreds of years, these heat will eventually turn up again to the sea surface. Considering that the temperature of the Earth's surface had already increased significantly at that time, the heat from the oceans turning up will lead to a secondary rise in global temperature and bring more serious impacts on the global climate, and this delayed effect of ocean heat should be given more attention." "Attention." Su Jingzhi emphasized.

Experts call for more precise ocean observation and in-depth demonstration of the ocean's climate "code" to become more important than ever in today's increasingly severe impact of climate change. At the same time, the public should be aware of the important role of the oceans in the Earth's climate system, reduce greenhouse gas emissions, and pursue a green and low-carbon development path.