The origins of climate change

The atmospheric concentration of greenhouse gases and particulate matter is changing as a result of human activity. Greenhouse gases like carbon dioxide (CO2), methane (CH4), nitrous oxide (laughing gas) (N2O) and water vapour alter the permeability of the atmosphere to electromagnetic radiation. The problem that arises here is that the atmosphere retains its permeability to short-wave radiation which strikes the earth from the sun. The long-wave thermal radiation which is radiated back into the atmosphere from the earth is being increasingly absorbed by the higher concentrations of greenhouse gases. As a result the atmosphere’s radiation balance (incoming thermal radiation – outgoing thermal radiation) is positive and warming occurs as a result.

 

The development of the concentration of the greenhouse gas carbon dioxide shows an increase from 280 parts per million (ppm) in pre-industrial times to around 380ppm today. As it has been possible to reconstruct from ice bores, today’s concentrations of the most important greenhouse gases is significantly higher than at any other time in the past 650,000 years.

Based on these observations, climate models have also calculated that the earth’s atmosphere will continue to heat up clearly in the future as has already been observable for the last century in measurement series. The map shows the expected change in temperature and precipitation for Europe towards the end of the 21st century as compared with the average values for the period 1980 – 1999.