Question: How would we be affected by a warmer climate?

James Pope answered on 25 Jun 2012:

Hi lucysugden,

It’s a good question, and in some respect we don’t know. I must confess I have edited my answer to this a couple of times. The key concept in the impacts of global warming is the amount of warming. An estimate of 2°C of warming by 2100 is seen as being below the level that is dangerous, but this would still have impacts and one big climate scientist, an American, James Hansen who works at NASA thinks we need to keep it to 1°C.

If we go over this level of warming, we will start to see an increase in areas that get such little rainfall they become deserts, so a large Sahara desert in Africa, but also the southern states of the USA (Texas, Ohio etc) could be come unihabitable. Likewise a large chunk of China could become desert if warming is above 2°C. A key area for this change would be over India, were the monsoon rains are vital for the growing of the rice crop, if the monsoon doesn’t happen as strongly in a warmer climate than 1 billion people are suddenly in a country where the main food supply has been lost or massively reduced. Other areas could see reductions in crop growth due to changes in the climate of a warmer world, although some areas (such as the UK) will probably see an increase in crop growth.

Another big impact from high levels of warming, is the reduction in size of the Amazon rainforest, which is such a beautiful and diverse bioloigical habitat, containing species we haven’t discovered yet, so it getting shrunk by climate change could cause a lot of extinctions.

The most noticable impact for the UK is liekly to come from extreme weather, so stronger storms in winter and more variable weather in the summer, we’ll go from extremes of really good summers to really horrible summers from the looks of how predictions are going. Elsewhere in the world the strength of Hurricanes will increase so we see more like Hurricane Katrina (in 2005). Tornadoes in the USA will also become more common and more destructive.

We are possibly already seeing some of tehse impacts now, but it’s hard to be sure until we look back over a few decades of data, but by the time we have this data, it may be too late!