气候模式应用中的不确定性分析

为了分析和评价气候变化对水文水资源的影响,根据中国东部地区1956～2000年实测年降水量系列数据,采用多年均值、系列趋势变化指标和反映系列可持续特性的Hurst系数等3项指标,对CGCMA3、MPI-ECHAM5和平均GCM等3种气候模式模拟的同期年降水系列数据进行了检验。检验结果表明,3种气候模式模拟结果与实测值之间,以及不同模式模拟结果之间,不仅定量方面差异很大,而且在定性方面甚至出现相悖的结果,不确定性十分显著。同样,根据3种气候模式预测的未来2001～2050年年降水量和季平均气温推得的未来年径流量系列数据,其多年均值、系列趋势变化指标和干旱年年径流量多项指标也存在明显的不确定性。据此对气候模式及其应用提出了相应的建议。

Uncertainty analysis in the application of climate models

In order to analyze and assess the impact of climate change on regional hydrology and water resources, three indices including average annual precipitation,the trend index and Hurst coefficients reflecting the continuity of hydrology series are calculated on the bases of measured annual precipitation series in the east of China from 1956 to 2000,and then compared with those calculated on the bases of the simulated annual precipitation series from each of three climate models(CGCMA3,MPI-ECHAM5 and Average GCM).It is found that each index values between the observed and simulated series are different quantitatively and even contradictory qualitatively.This indicates that the uncertainty is significant in the application of models.Similarly,average annual runoff,the trend index and annual runoff of different drought years for the future annual runoff series from 2001 to 2050 also have significant uncertainty. Future annual runoff series is produced by using the predicted annual precipitation and temperature data from three climate models.Finally,some suggestions on climate models and its application are proposed in this study.