Archive – The sun rises behind the high voltage towers. Photo: Sebastian Julino / D
Between 2005 and 2019, the so-called energy imbalance on Earth nearly doubled, researchers from the US climate agency NOAA and NASA said in the journal “Geophysical Research Letters.” This trend is primarily due to increased solar radiation absorbed due to reduced reflectivity from clouds and sea ice. At the same time, long-wave radiation from Earth to space, through which energy and therefore heat are released, has decreased, due to an increase in greenhouse gases in the atmosphere, among other things.
It is based on a sensitive energetic balance on Earth: on the one hand, the Earth’s atmosphere and surface absorb sunlight, and on the other hand, the Earth emits infrared radiation into space. If both processes are in balance, then the energy balance is balanced. A positive energy balance means that the Earth is warming. As the oceans absorb about 90 percent of this excess energy, the waters in the seas are warming.
However, energy imbalance can also be affected by natural factors. According to scientists, the Pacific Nodes (PDO) may have a role in particular. However, the surface water temperature in the Pacific Ocean is changing dramatically – a particularly warm phase, as between 2014 and 2020, contributes to the fact that the Earth absorbs significantly more solar radiation.
“It’s probably a combination of human motivation and internal change (on Earth),” said study leader Norman Loeb. Combined human and natural factors “have caused a warming that leads to a fairly significant change in the energy imbalance on Earth. The scale of the increase is unprecedented.” Loeb stressed that the study is only a snapshot of long-term climate change and that it is not possible to predict with any certainty what the Earth’s energy budget may look like in the coming decades. (SDA)