Faculty-conducted study takes a physics look at climate change
Amidst walls decked with posters of the solar system and celestial bodies, physics professor Liming Li often sits in his office on the fifth floor of Science and Research Building 1, contemplating the mysteries of the cosmos. In his latest publication, he brought his intellect down to Earth.
The study, recently published in “Nature Communications” and co-authored by two other members of the faculty, views the Earth’s atmosphere as a heat engine in order to analyze climate change from an innovative angle.
“Global warming is well-studied from a meteorological standpoint, but there is a different way to understand this phenomenon,” Li said. “My idea was to check this concept from a physics perspective.”
Co-author and Earth and atmospheric science professor Xun Jiang and Li say they view the Earth’s atmosphere as a physics machine that converts energy from the sun into energy of motion, called a heat engine, in order to verify climate change results that have been observed.
“Variation of global surface temperature over time is a very complicated problem, which is affected by many factors, including the atmospheric energetics, which we studied,” said Jiang.
Heat engines, a subject covered in many physics II classes, are simply machines which convert potential energy into kinetic energy. This research investigates the Earth’s atmosphere as it functions like a heat engine, converting the potential energy received from the sun into kinetic energy that moves molecules of air around the atmosphere to create weather.
“These findings indicate that there should be more eddies, more storms (and) more hurricanes in the future,” Li said.
The study found that the rate at which the Earth is converting the potential energy into kinetic energy is increasing over time. This means that the same amount of energy from the sun is able to cause more meteorological activity today than it would have 35 years ago.
Findings from this study indicate the efficiency of the Earth as a heat engine is increasing, which means the effects of global warming are increasing.
Researchers were able to analyze three independent sets of three-dimensional data collected over a 35-year period, with only the help of complicated computer code that utilized Lorenz equations.
“The Lorenz equations are used to describe the potential and kinetic energies and the conversions among those energies in the atmosphere,” said Gan Li, another co-author and graduate student at Guilin University.
The Intergovernmental Panel on Climate Change suggests that global surface temperature will continue to increase in the future, which could snowball into global weather abnormalities.This study in particular points out that the increasing efficiency of the Earth as a heat engine is a possible explanation to the bouts of severe weather that have ravaged certain areas of the globe.
Though it is clear that the Earth’s climate is changing, it’s uncertain what is causing the conversion rate to go up.
“The physics behind the increased efficiency is still unclear,” said Jiang.