This study dispels the fallacy that says we shouldn't be concerned about climate change because it is entirely natural.
A recent study demonstrated that specific signals from human activities have changed the temperature structure of the Earth's atmosphere, demonstrating that climate change is caused by humans. Differences in temperature trends between the troposphere and the lower stratosphere have long been known by scientists as a "fingerprint" of anthropogenic climate change.
The incorporation of information from the mid to upper stratosphere, 25 to 50 kilometres above the Earth's surface, would have increased the detectability of a human fingerprint by a factor of 5, according to the study's experts, but this fingerprint omitted that information.
The study published in Proceedings of the National Academy of Sciences (PNAS) stated,, “Enhanced detectability occurs because the mid to upper stratosphere has a large cooling signal from human-caused CO2 increases, small noise levels of natural internal variability, and differing signal and noise patterns.”
Day-to-day weather, interannual variability brought on by El Nino and La Nina events, and longer-term naturally occurring climatic oscillations are all examples of noise in the troposphere. In the upper stratosphere, the signal of human-caused climate change is stronger and more easily distinguishable due to lower levels of fluctuation noise.
This is the most conclusive proof of a human-caused climate change signal connected to CO2 rises, according to lead author Benjamin Santer, an adjunct scientist in the Physical Oceanography Department at the Woods Hole Oceanographic Institute (WHOI) in Massachusetts, US. This study disproves the myth that because climate change is purely natural, we don't need to take it seriously.
This study demonstrates that changes in the real world are simply too profound to be accounted for by natural processes.
Due to improved simulations and satellite data, this layer, which sits between the mid and upper stratosphere, may now be examined in greater depth. The current study, according to the experts, is the first to look for patterns of climate change induced by humans in the middle and high stratosphere.
The fact that observations show not only a warming troposphere but also a strongly cooling upper stratosphere is unique tell-tale evidence that nails the dominant role of carbon dioxide in climate change and significantly boosts confidence, according to co-author Susan Solomon, Martin Professor of Environmental Studies at the Massachusetts Institute of Technology.