Massachusetts Institute of Technology researchers concluded in their new paleoclimate study that “warming bias” will occur if ice sheets continue to disappear. Reference to “warming bias” denotes that more extreme warming events rather than cooling events will transpire as results of temperature shifts.
According to the researchers, it may be because of the “multiplier effect” created by volcanic eruptions that emit large amounts of carbon dioxide into the atmosphere. Such occurrences accelerate chemical and biological processes; leading to an increase of fluctuations that create more warming events.
They added that the last warming bias vanished around 5 million years ago when ice sheets began materializing in the Northern Hemisphere. Today, as the Arctic ice subsides and eventually disappear, the study implies this might trigger a new period of warming bias that is aggravated by anthropogenic global warming.
How the MIT Research Team Conducted the Paleoclimate Study
The team of researchers examined large databases of sediments containing deep sea unicellular organisms that have been around for millions of years. The organisms have been fossilized through their hard shells. Their compositions change depending on the ocean temperature while they were growing, which made their hard shells a reliable source of information in finding out the Earth’s ancient temperatures.
The composition of shells have been studied by scientists for many decades as they were collected from all parts of the world during various time periods. This allowed the group of MIT researches to discover that the Earth’s temperature had fluctuated for millions of years.
Lead author Constantin Arnscheidt mentioned that usually, previous studies concentrated on the individual large spikes noted by other researchers in their data analysis. Instead of doing the same, the MIT team reviewed the overall statistics and considered all of the fluctuations involved.
The research team found out that over the last 66 million years, the distribution of global temperature fluctuations did not reveal equal probabilities between extreme cool and extreme warm temperatures. Their analysis was distinctly asymmetrical, which showed more warm events exhibiting a longer tail that denoted more warming conditions likely to happen.