Sea levels have risen by 10 – 20 cm. This is due to the expansion of warming oceans. Temperature records show that the average temperature has increased by about 0.6ºC in the 20th century.The Kyoto Protocol (1997) commits industrialized countries to reduce their greenhouse gas emissions. It suffered a huge set back in 2001 when the USA, responsible for a quarter of global emissions, pulled out.The planet’s climate is constantly changing but now scientists believe that the extreme changes taking place today are a result of human activity. The changes we see today may affect the stability of the climate on which much life on the planet depends.The term refers to the role played by the layer of gases, including carbon dioxide, methane and nitrous oxide, which trap the heat from the sun in the earth’s atmosphere. We need the layer to keep in some of the heat but now the concentration of gases, especially CO2 is increasing and retaining more heat.It is difficult to predict, but we can expect more extreme weather conditions like floods, storms and heat waves. Scientists believe there will be more rain but also a higher risk of drought in inland areas