Strålingsforcing

Strålingsforcing is a concept used in climate science to describe the change in the net flux of radiation at the top of the atmosphere of the Earth. It is a measure of how much human activities or natural events are altering the Earth's energy balance. A positive strålingsforcing indicates a warming effect, meaning more energy is entering the climate system than leaving it. A negative strålingsforcing indicates a cooling effect, where more energy is leaving the system than entering.

The primary drivers of strålingsforcing are greenhouse gases, such as carbon dioxide, methane, and nitrous oxide. When these gases increase in concentration in the atmosphere, they trap more outgoing infrared radiation, leading to a warming effect. Other factors that can cause strålingsforcing include changes in solar irradiance (the amount of energy the sun emits), volcanic eruptions (which can release aerosols that reflect sunlight), and changes in land surface albedo (how much sunlight is reflected by the Earth's surface).

Quantifying strålingsforcing allows scientists to compare the relative impacts of different climate change drivers. For example, the increase in greenhouse gas concentrations since pre-industrial times has resulted in a significant positive strålingsforcing, largely outweighing any negative forcing from other sources. This forcing is the fundamental driver of the observed global warming. Understanding strålingsforcing is crucial for climate modeling and for projecting future climate change.