• Melting of ice sheets over land and sea ice over the oceans
• Rising sea levels due to thermal expansion of the oceans and the addition of water from melting ice at the poles. There is evidence of massive cracks in polar ice caps that will release huge quantities of fresh water into the seas.
• Increasingly chaotic weather throughout the World. More storms, flooding etc
• Changes in world climatic zones involving changes in precipitation, temperature, cloudiness and soil moisture patterns
• Changes in the carbon cycle
• Changes in patterns of farming around the world.

In particular these changes may influence the UK quite significantly. The weather is expected to become much more changeable and unpredictable. We could experience warmer spells and colder spells, periods of high winds, periods of high rainfall etc. Perhaps we might naturally look at a warmer UK as an advantage, which would give us a better climate and allow us to grow a wider range of crops here. The possibility of a colder UK is actually quite likely.

The UK is particularly vulnerable to global warming, partly due to flooding of low-lying land but potentially more serious due to the possible changes to the Gulf Stream.

The Gulf Stream brings warm water from the tropics (Gulf of Mexico) as part of a world-wide network of ocean currents. The system depends upon the 'natural pumps' around Greenland which draw warm water up towards Northwest Europe (Ireland, Britain and Scandinavia) and sends cold water back Southwards.

This Gulf Stream, sometimes called the 'Atlantic Conveyer' is actually a flow of warm water equivalent to the entire rainfall in the world; or in terms of heat, each day carries about 100 times the total daily energy use by the entire worlds population. The mild winters, cool summers enjoyed by the UK are due to the Gulf Stream, which crosses the Atlantic to keep our western coastlines moderately warm throughout the year.

The melting of the Arctic ice cap might produce southerly flows of cold water to mix with the Gulf Stream and possibly to disturb the pumping mechanism. If the Gulf Stream were to fail temperatures over Northern Europe would plummet by more than 10^oC during winter months. The UK winter climate would then be comparable to that of Labrador or Siberia. It would be difficult to support our current population in such circumstances.