Based on the ground routine observation and the NCEP/NCAR reanalysis data, the abnormal high temperature over Northern Hemisphere from June to August of 2010 were analyzed. The results show that, most areas over the Northern Hemisphere and some regions experienced high temperature departure above +6 ℃.The positive temperature anomaly in the troposphere reached its maximum value on the record for the recent 30 years. There were 3 durations in China with the longest high temperature. There were 249 stations (about 30％ of the total stations) on July 30 with Tmax ≥ 35℃, 10 stations(1.2％ of total station) with Tmax ≥ 40°C.The longest duration of high temperature over northwest China was from July 27 to the 2nd of Aug. The Tmax and duration over 4 provincial cities did not break the extreme record in history. It was consistent at all pressure levels in the troposphere in the region with anomalous high temperature. The potential heights were obviously higher than the positive departures. The departures in July and August were the highest in the recent 30 years,except in June with a sub-peak. The distribution and the centers of the positiveegative height departures were substantially consistent with those of the temperature departures in each level of the average height field,with a positive correlation. That might have resulted in the occurrence of the anomalous high temperature and enhanced the time of duration in temperature.%利用常规气象观测资料、NCEP/NCAR再分析资料,对2010年夏季6-8月北半球异常高温现象进行了分析.结果表明,夏季北半球大部分地方地面气温偏高,局部地区气温异常偏高,地而气温距平值达+6℃;北半球对流层平均气温正距平值达近30年以来最大值,并且各月平均气温异常偏高的区域,在对流层各层次都表现为一致的偏高;北半球对流层平均高度也明显偏高,都为正距平,除6月的距平值为次高值外,7月和8月的距平值也是近30年来的最高值.中国有三个大范围的高温时段,7月30日是高温范围最大的一天.有249个站最高气温Tmax≥35℃,还有10个站Tmax≥40℃,分别占总站数的30%和1.2%,最高气温Tmax≥40.C的站数要远远少于Tmax≥35℃的站数;7月27日-8月2日,是中国西北地区高温持续时间最长,影响范围最大的时段,但4个省会城市的最高气温、最长持续时间没有突破历史极值.进一步分析表明,各月各层次平均高度距平场上,正负高度距平的区域以及中心位置的分布与平均气温距平场正负距平的分布基本一致,高度距半正值区域对应平均气温距平的止值区域.气温场与高度场的这种分布特征导致异常高温的出现,加剧了高温持续的时间.
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