Climate scientists have been repeatedly highlighting the warning signs of climate change and how it is affecting the planet. Past data has revealed that temperatures similar to the present global average caused sea level increases of over 20 feet. A new study in the journal Science claims just that: we are facing a similar outcome if we don’t move towards changing the current climate trend.
An international team of researchers led by Andrea Dutton, from the University of Florida, has attempted to reveal exactly what is at stake. Their work compares the present climate situation with tree distinct warmer periods from the Earth’s history that are comparable to what we are now experiencing.
The team concluded that, in each of the three warm periods they studies, sea levels experienced rises of over 20 feet. Though neither of these periods is a perfect analogue to the current global average, Dutton explains, the data should not be overlooked.
“We looked at several of the warmest interglacials, and for each of them, we’re finding at least 6 meters worth of sea level rise,” she said.
Dutton, a Florida University geochemist, notes that the evidence obtained by the team of researchers points towards a disequilibrium between the polar ice sheets and the present climate. They used computer models as well as geologic records to assess the effects of temperatures averaging 1-3 degrees more than preindustrial temperature levels.
They explain that there is an unequal warming pattern to be taken into account. The planet warms, however, the poles do so at a much faster rate. This raises concerns as to whether the ice sheets in Antarctica and Greenland will respond similarly.
Of course, a sea level rise of such proportions won’t be an overnight occurrence. The team’s work is aimed at raising awareness and pointing out exactly how sensitive polar ice sheets are to temperature shifts.
Sea level rise is deceptive, Dutton points out, as thermal expansion and glacier loss worldwide tend to interfere with correct measurements. As part of the climate system, sea levels respond slowly and a 20 centimeter sea level increase (the one that we have seen in the past 100 years) is only the minute beginning of what will unavoidably be a larger sea level rise.
One notable aspect of the team’s study is the difference in atmospheric carbon dioxide levels. During the three periods taken into consideration by the researchers, these levels peaked at approximately 280 parts per million. However, nowadays, carbon dioxide levels in the atmosphere are well over 400ppm.
Of course, much uncertainty still remains around such studies and further research is required to offer definitive answers.
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