1994-2004 saw some of the hottest temperatures ever known on earth. The global temperature 'only' rose by 0.75 °C over the course of the 20th century, but some experts are warning that we could see an alarming rise of 2-4°C by the end of the 21st century.

Climate change is caused by greenhouse gas emissions and human activity.

According to Greenpeace figures taken from scientific studies, there are two possible scenarios: by 2100, we could see a rise of 4° and London could be underwater. On the other hand, according to some scientists we could also see a return to a mini Ice Age (a drop of 5-10°). This is because the Gulf Stream, which gives Western Europe its generally balmy climate, is slowing down (with global warming possibly to blame) and could fail altogether. 

Also, extremes such as the scorching heatwave we had back in 2003 could become commonplace. According to Greenpeace, it's highly likely that the summers from 2070-2099 will be just as hot as the heatwave of 2003 - which contributed to 30, 000 deaths in Europe alone.

Whatever your views on the outcome of climate change, one thing is for sure: there will be sweeping changes taking place in our lifetimes. So what can we do about it?