Although there is great uncertainty about exactly how climate change will affect us, researchers who have prepared reports for the Intergovernmental Panel on Climate Change (IPCC) highlight the following possibilities:
Sea level rises: At present some 46m people live in areas at risk of flooding due to storm surges. Scientists estimate that a 50cm rise in sea level would increase this number to 92 million and a one-metre rise would put 118 million in peril.
If the global ocean level went up by one metre
- Egypt would lose 1% of its land area
- The Netherlands would lose 6%
- Bangladesh would lose 17.5%
- Some 80% of the Majuro Atoll in the Pacific Marshall Islands would disappear under water
Crops and productivity:
It is thought that total global crop production would be unchanged but regional effects would vary widely.
- Those most at risk from famine would be people relying on isolated agricultural systems in arid and semi-arid regions
- Populations particularly under threat live in sub-Saharan Africa, south east Asia and tropical areas of Latin America
- Climate change could also alter the range of agricultural pests
Disease: Extensions of the geographical range and season for some organisms could result in increases of diseases like malaria, dengue fever and yellow fever.
- If the temperature increases by 3-5 degrees Centigrade the number of people potentially exposed to malaria could go up from 45% to 60% of the world population and result in an extra 50-80 million cases a year
- Air pollution and exposure to greater extremes in temperature could lead to a greater frequency of asthma and respiratory diseases
Ecosystems: Scientists predict that composition and range of many ecosystems will shift as species respond to climate change
- Research models project that a substantial fraction of the world's forests, and possibly up to two thirds, will undergo major changes. They say the species composiiton will change and some forest may disappear all together
- Deserts are likely to become more extreme, resulting in increased soil erosion
- Mountain glaciers could retreat and inland wetlands would be affected by global warming with resultant changes in habitat for the current species