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The temperature,precipitation around last century retrieved by tree ring in the northern and middle parts of Ningxia were used to fit and prolong the series of precipitation and temperature anomaly in the sandy lands to the east of the yellow river and the climate tendency in the last century was analyzed.The climate features there were studied in detail using the meteorological data from six typical stations.The results show that it was cold and dry in the first three decades;then turned warm and wet till the mid of the 1950s.After the end of 1950s,there was a typical cold and wet period,and after the 1960s it was relatively cold and dry.Since the middle 1980s till now,it was relatively warm and dry.The temperature,precipitation,evaporation,relative humidity and average wind velocity varied in different places and different periods.