This 2007 report written by the Intergovernmental Panel on Climate Change, has made it clear, we need to act now if we want our world to be livable, and not a complete catastrophe in the near future. Many statistics are shown in this report, with very high numbers in increasing temperatures, natural disasters, acidity in the oceans rising, intense precipitation and intense droughts, etc. For example, the average arctic temperatures increased at almost twice the global rate in the past 100 years. Temperatures of permafrost has been rising since the 1980’s in the Arctic. The area covered by permafrost has decreased by 7% in the Northern hemisphere since 1990 with a decrease in the spring of 15%. Arctic sea ice has shrunk by 2.7% per decade, and 7.4% decrease in the summer months since 1978. The IPCC has also reported that there has been heavy precipitation in the Eastern parts of North and South America, Northern Europe and Northern/Central Asia. While these places are getting intense precipitation, the Sahel, Mediterranean, South Africa and parts of southern Asia are drying out. Another data point in the report, is that the total global sea level rise in the 20th century is estimated to be 0.17 metres. All of these examples from the text are due to the increase in greenhouse gas concentrations.
Question : What consequences can we expect from global warming?
Some of the consequences, based on the IPCC report, are the slowing down of the meridional overturning circulation of the Atlantic ocean during the 21st century. It is estimated that in 2100, the global temperature will increase by 4 degrees celsius. With increased CO2 concentrations, the acidity of the ocean will increase even more, which will kill all the coral reefs and kill many aquatic species. If the sea level keeps rising for a millennia, there will be no more Greenland ice sheet. More consequences, are intense winds in both hemispheres, more intente and longer droughts, changes in wind patterns, increased frequency of heavy precipitation because of increased water vapour. There will also be an increase in tropical cyclones, which are devastating for communities as well as their home land. All in all, the consequences we can expect from global warming are nothing but tragic to our earth.