The temperature is rising and so is the sea. Temperature readings from around the world show that in the last 100 years the earth's temperature has gone up by between 0.4 and 0.8 degrees centigrade. In the same time, sea levels have gone up by between 10 and 25 centimetres and extreme weather events (including floods and heatwaves) are happening more often and seem to be getting worse.
This doesn't sound much, but scientists are worried because these changes are happening much quicker than before and it looks like they're going to carry on speeding up - especially if we don't take action.