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利用次季节-季节(S2S)预测计划的五个数值模式历史回报,评估了东亚5～9月土壤湿度的模式预测技巧.发现在中国南方和东北,多数S2S模式对土壤湿度的有效预测可提前5～10天;在我国青藏高原和西北地区,仅有欧洲中心模式的有效预测能提前20天左右.一般来说,土壤湿润区的预测技巧好于干燥区,多数模式在9月的预测技巧高于其余月份.然而,模式间的预测技巧还存在较大的差异.此外,厄尔尼诺-南方涛动对土壤湿度的S2S技巧也具有一定的影响,当发生厄尔尼诺(拉尼娜)事件时,我国东部的土壤湿度预测技巧偏高(低).与大气变量相比,土壤湿度的预测技巧明显偏低,说明陆面过程的次季节预测还有待进一步的提高.“,”Based on the reforecasts from five models of the Subseasonal to Seasonal (S2S) Prediction project,the S2S prediction skill of surface soil moisture (SM) over East Asia during May-September is evaluated against ERA-Interim.Results show that good prediction skill of SM is generally 5-10 forecast days prior over southern and northeastern China in the majority of models.Over the Tibetan Plateau and northwestern China,only the ECMWF model has good prediction skill 20 days in advance.Generally,better prediction skill tends to appear over wet regions rather than dry regions.In terms of the seasonal variation of SM prediction skill,some differences are noticed among the models,but most of them show good prediction skill during September.Furthermore,the significant positive correlation between the prediction skill of SM and ENSO index indicates modulation by ENSO of the S2S prediction of SM.When there is an El Ni(n)o (a La Ni(n)a) event,the SM prediction skill over eastern China tends to be high (low).Through evaluation of the S2S prediction skill of SM in these models,it is found that the prediction skill of SM is lower than that of most atmospheric variables in S2S forecasts.Therefore,more attention needs to be given to the S2S forecasting of land processes.