本文作者： 21ST
THE change in temperature from a long-term average is used to measure climate change. The chart below shows the global temperature change since 1880. The US National Oceanic and Atmospheric Administraion used the mean (平均的) temperature in 1880 as a reference value (参考值), and compared the following years’ temperatures to that figure. We can see that it’s getting warmer and warmer.