基于ERAlnlerim资料的2003年淮河流域梅雨期水汽收支分析

以2003年6月29日-7月11日淮河流域梅雨期强降水为研究对象，采用ERAInterim再分析资料和站点降水资料，综合分析该期间慢降水时段水汽收支。结果表明：降水主要来自低层水汽辐合的贡献，而与低空急流相联系的水汽辐合具有显著的日变化，即后半夜至凌晨最大，午后最小，并由此造成了梅雨期强降水独特的日变化特征，最强降水出现在后半夜至凌晨；蒸发主要集中在白天，夜晚很小，数值约为降水量的15％，表明局地水循环的重要作用。针对淮河流域强降水区进行的水汽收支计算表明，水汽收支方程左、右两边数值在整个强降水时段具有较好的一致性，相关系数为0．77；对整个强降水期取时间平均，获得的水汽收支方程左、右两端数值的偏差为18％。

Moisture budgets over the Huai River Basin during the 2003 Meiyu season by using the ERA Interim reanalysis data

Moisture budgets during heavy rainfall events in the Huai River Basin from June 29 to July 11 of the 2003 Meiyu season are stud- led by using the ERA Interim reanalysis dala and rain gauge records. It is shown that the water supply to the raiinfall is mainly from the low-lev- el convergence of moislnre. The moisture emlvergenee assoeialed wilh the low-level jel has a remarkable diurnal variation with a maximum during midnight to early morning and an afternoon minimum, which produees a eharaeleriste preeipitalion diurnal eyele during the Meiyu sea- son. The ewq~oratiml mainly concentrates in the daytime and ~onstitntes about 15% of the amount of precipitation, indicating the importance of ｜he regi~nal moisture recycling. Over Ihe Huai River Basin, lhe left and righl sides of the moislure budget equation have a good ennsisteney with a eorrelalion eoeffieienl of 0.77 throughout lhe 2003 Meiyu season. When averaged over time, a moisture imbalance of 18% is oblained.