Abstract:

Based on the daily observational data of precipitation,temperature and weather phenomena of 33 stations over Three Gorges Reservoir area during the period 1961 to 2006,the linear trends of some major meteorological disasters like drought,flood,continuous rain,heat wave,fog,thunderstorm were analyzed.It was found that the average annual drought days have a slight increasing trend in the Three Gorges Reservoir area. There was no significant change in seasonal drought days of spring,summer and winter,while an upward trend in autumn drought days at a rate of 4.1 d/10 a was found.The analysis of precipitation showed that the presence of flood days decreased slightly in autumn,while the annual continuous rainy days decreased significantly and yearly thunderstorm days had decreased at a rate of 29 d/10 a.The foggy days in Three Gorges Reservoir area had no obvious change as a whole,while significant decrease trend was found since 1999.Average extreme high temperatures had no upward or downward trend,but heat wave days had a slight downward trend.

Key words: Three Gorges Reservoir area/meteorological disasters/changing trends