The observation record of the artificial satellite reveals that the speed of sea level rise is accelerating

byklem @ s

In recent years, alarm bells on climate change caused by global warming are actively being played, and the fact that the average temperature of the earth is risingMovie you can see at a glanceAnd others are also made public. Meanwhile, Ars Technica reports that "It is clear from the satellite photograph that the rising speed of sea level is accelerating."

Yes, sea level rise really is accelerating | Ars Technica

Climate Change: Vital Signs of the Planet: Sea Level

People who dispute the theory that "the earth is warming by human activities" said, "Although the rise in sea level is no doubt the fact is that the speed of the rise has been linear all the time, human activities are affecting It is said that rising sea level is a natural phenomenon. " This argument itself ignores the fact that the sea level rises due to melting glaciers, but when referring to the record of the sea surface by the satellite that began in 1993, the speed of sea level rise is obviously accelerating It seems to be understood that it is.

The sea level observation from the satellite can be more reliable than the tide gauge based on the ground which is moving due to the influence of the earthquake etc. However, since the period from the start of recording is short, a slight special climate has a big influence I will give it. For example,El Niño phenomenon and La Niña phenomenon, The sea level that the ocean currents will rush to the continent will change due to unusual influences.

"As described above, it is a very complicated task to accurately calculate sea level variations from satellite photographs, but scientists did not give up," Ars Technica says.

byUnited Nations Photo

According to recent research, Ocean Observing SatelliteTOPEX / PoseidonIt was several millimeters for error correction of the sea level which was done byThere was an error.It turned out to be. Also, it occurred in 1991, which is just before the observation of the sea level by the satellite startedPinatubo MountainOf the eruption, compared to the case where the eruption did not occurPossibility to lower sea levelWas revealed. Taking these into consideration, the sea level rise observed by the satellite is thought to have decreased more than it actually was.

In the figure below, the blue line shows the observation record of the sea level by the satellite without any correction. The red line corrects the influence of the eruption of Mount Pinatubo against the observation record of the satellite, and the green line is the correction of the deviation of TOPEX / Poseidon. From the start of the observation from 1993 to 2017, the sea level has risen by 2.9 mm per year on average, and the sea level rising speed is 0.084 mm ± 0.025 mm per year. A research team at the University of ColoradoAnnouncedThe result of this research is that "the acceleration of the sea surface is due to melting of the ice of Antarctica and Greenland".

According to Ars Technica, if the rise of the sea level progressed without relaxing acceleration, the sea level will be 65 centimeters higher than in the present year in 2100. This seems to be equivalent to twice that when there is no acceleration and it shows that accelerating sea level rise by the melting of Antarctic and Greenland ice has a very big impact.

Also, Ars Technica says, "This estimate is even optimistic." Because the results of this research are based on satellite records extracted from 1993 to 2017 for only 25 years, and if the speed with which ice of Antarctica and Greenland melts further accelerates in the future, the sea level rise will further increase It is because it becomes big. 2017 is the history of observationIt was a warm year for the top classResearch results have also come up, and there is a possibility that future sea level rise will exceed the estimate in the future.

in Science, Posted by log1h_ik