Abstract: For revealing and exploring climate change and its causes, Granger causality test is introduced in this paper. In presenting the basic principle of the Granger test, several climatic variables are tested for their impacts on temperature changes in China by means of the Granger causality test, and the possible physical connections between these variables and temperatures in China are revealed. The focus lies on the impact of CO2 concentration on temperature changes in China; further, the cause for the lag of temperature changes in China relative to global warming is explained reasonably. Thus it is proved that the Granger causality test may be a new and useful method of the detection and attribution of climate change and its feasibility is demonstrated.

Key words: climate change, detection and attribution, Granger causality test, weather forecast