ThecropmodelWorldFoodStudies(WOFOST)wastunedandvalidatedwithmeteorologicalaswellaswinterwheatgrowthandyielddataat24stationsin5provincesofNorthChinafrom1997to2003.Theparameterizationobtainedbythetuningwasthenusedtomodeltheimpactsofclimatechangeonwinterwheatgrowthforallstationsusinglong-termweatherdatafrom1950to2000.Twosimulationsweremade,onewithallmeteorologicaldata(rainfed)andtheotherwithoutwaterstress(potential).Theresultsindicatethatthefloweringandmaturitydatesoccurred3.3and3daysearlierinthe1990sthanthatinthe1960sduetoa0.65℃temperatureincrease.Thesimulatedrainfedyieldsshowthattheaveragedroughtinducedyields(potentialminusrainfedyields)havedecreasedby9.7%overthelast50years.Thisistobecomparedwitha0.02%decreaseinyieldiftheprecipitationlimitislifted.Althoughtheprecipitationduringthegrowingseasonhasdecreasedoverthelast50years,thedroughteffectsontherainfedyieldsremainedtobepracticallyunchangedasthespringprecipitationdidnotdecreasemarkedly.
