World scientists and most world politicians agree that the world is getting warmer, due largely to human activities. IPCC
There is also large agreement that the world will warm - by about 2 degrees by about 2050. This is considered manageable, although this will cause problems of exagerated climate changes in particular parts of the world. However, any rise over this could have serious uncontrollable 'runaway' effects such as the seas and land warming, setting up a scenario that would be impossible to stop.
The cause of this change is reckoned to be "industrialisation" - in particular, the concentration of carbon dioxide in the atmosphere (although water vapour is a much bigger element of warming, it has always been there and its fluctuations less predictable). The UNFCCC uses the term "climate change" for human-caused change, and "climate variability" for other changes.
At present there are 383 parts per million (ppm) of CO2in the atmosphere. This rises by about 2 ppm a year - an extra 4 ppm are emitted, while 2 ppm is reabsorbed mainly through forests.
It is easy to calculate that by 2050, concentrations will have reached about 450ppm - the amount required to bring about 2degrees warming. Clearly, we will have to slow down long before that if we are to avert the "runaway" scenario, sometime shortly after that date.
|Main sources of emissions..
Carbon dioxide is the main - but not only gas, that is produced by industrialisation.
Industrialisation is a quite normal natural process consisting of burning fuel (measured in calories) to make energy for our productive processes to run. The same occurs when we run - we burn calories of food, to give us the energy. However if we run too fast we soon run out of breath as the carbon dioxide accumulates - or we run out of energy..
Carbon Cycle consists of a contnous recycling process of carbon moving from bodies through the earth and and air. The trouble is that too much is accumulating in the aire. Where do you consider carbon should be - in the land, air water or our bodies?
Along with methane and nitrous ocides, CO2 make up the "Global Warming Potential".
Food/Farming - about 1/5th GWP worldwide
refer to these other units..