The Earth is warming from human activities, primarily because of increased carbon dioxide and other greenhouse gases in the atmosphere. This creates an energy imbalance at the top of the atmosphere called Earth’s energy imbalance.
A new study- published today in the first issue of Environmental Research: Climate, a new open-access journal- suggests that knowing the earth’s energy imbalance is vital in gauging the size and effects of climate change.
Distinguished scholar at the National Center of Atmospheric Research (NCAR) and highly cited lead author Kevin Trenberth and climate scientist and co-author Lijing Cheng have made a new complete inventory of all the various sources of excess heat on Earth. He studied energy changes from the atmosphere, ocean, land, and ice as climate system components from 2000 to 2019 and compared this to the radiation at the top of the Earth’s atmosphere to find the imbalance.
Trenberth said, “The net energy imbalance is calculated by looking at how much heat is absorbed from the Sun and how much can radiate back into space. It is not yet possible to measure the imbalance directly; the only practical way to estimate it is through an inventory of the energy changes.”
To understand and thus manage the climate catastrophe, it is essential to comprehend the net energy gain of the climate system from all sources, how much extra energy there is, and where it is redistributed in the Earth system. Previously, the focus of climate research has been on the rise of the global mean surface temperature on Earth. This is just one result of the overall energy imbalance that Earth is currently experiencing.
Excessive energy impacts weather patterns, directly increasing the frequency or intensity of extreme weather events, including hurricanes, wildfires, droughts, heat waves, heavy rain, and flooding. Weather events move energy, aid the climate system in releasing energy by radiating it into space, and impact global warming. According to the study, 93 percent of the excess heat caused by the imbalance is absorbed by the seas, raising their temperature and sea level and making 2021 the hottest year for the oceans.
Lijing Cheng, a co-author of the study, said, “Modelling the Earth energy imbalance is challenging, and the relevant observations and their synthesis need improvements. Understanding how all forms of energy are distributed across the globe and are sequestered or radiated back to space will give us a better understanding of our future.”
- Kevin E Trenberth and Lijing Cheng. A perspective on climate change from Earth’s energy imbalance. DOI: 10.1088/2752-5295/ac6f74