Climate in Taiwan was once benign with picturesque scenery. The warmth and moist in the climate helped bring rich and fertile products; nevertheless, today the global temperature keeps rising and disasters keep pouring in, leading floods and droughts to take place by turns frequently. This is the circumstance which we were not capable of predicting. In this golden era of science and technology development, we have accumulated much information about meteorology and observation, seen the changes in climate over a long period of time as well as proved the fact that the substantial GHGs emitted through anthropogenic activities was the major cause for climate change. If we hope to diminish the damage and prepare for the future, in addition to fortune-telling, is there a more scientific way? The measure which scientists take is – to set up the simulation scenario. Since we considered GHG the major cause of global temperature rising, IPCC has already made various hypothetical assumptions in terms of the potential development of future economy and energy use, proposing “Special Report on Emissions Scenarios, SRES.” There are four main scenarios in the report which are A1, A2, B1 and B2. Within A1, the scenario is distributed into three groups based on the uses of energy: A1T (with emphasis on the use of renewable energy), A1F1 (with emphasis on the use of fossil fuels) and the one that scientists regard as the most possible scenario in the future, A1B (a balanced use of renewable energy and fossil fuels).
The research team of Taiwan also selected scenario A1B. They used computers to calculate and obtain the simulation results on the future climate through General Circulation Models (GCMs), based on the GHGs emission between 2020 and 2039. Nonetheless, what are GCMs? GCMs depict the climate using a three dimensional grid over the globe. Scientists have developed numerous GCMs to simulate the climate. From the 24 internationally approved GCMs, we chose nine which suited Taiwan more and obtained predictions on the future climate in Taiwan such as temperature, precipitation and sea level after calculating.