青藏高原东北部近十年臭氧总量变化研究

Variation of Total Ozone over Northeast Tibetan Plateau in Recent Ten Years

利用青藏高原东北部青海瓦里关站1997年3月—2009年11月十多年的臭氧总量地基观测资料,对臭氧总量的年际变化、季节变化、频数分布、低值频率等特征进行分析。结果表明,近十多年来青藏高原东北部大气臭氧总量略有下降,臭氧损耗减缓;各年的频数分布呈左偏态分布,且夏秋季节(6—10月)的臭氧低值频率与同期臭氧总量平均值呈现极好的负相关,这可能是引起其年均值较低的原因之一;该地区臭氧总量具有明显的季节变化,夏秋季的臭氧低值频率远远高于冬春季,冬春季节臭氧总量平均约为300 DU,夏秋季节平均约为270 DU,最大值出现在3月份,最小值出现在9月份。臭氧总量的连续观测与分析对青藏高原的生态环境与气候能够起到预警作用。

The variation of the total ozone over Northeast of the Tibetan Plateau was analyzed based on more than ten years of ozone data at Waliguan atmospheric baseline observatory during 1997.03—2009.11.The inter-annual and seasonal variations of total ozone were discussed.Frequency distribution and low value frequency were also analyzed.It was shown that the total ozone over Waliguan decreased slowly.Frequencies of each year showed leftward non-normal distribution from 2000 to 2008.The low value frequency of total ozone from June to October of each year was negatively correlated with the mean value.It was one of the possible reasons of the lower total ozone value in Waliguan.The total ozone over Waliguan exhibited obviously seasonal variation.The low value frequency of total ozone in summer and autumn were much higher than thoes in spring and winter.The high value was approximately 300DU in winter and spring and the low value was about 270DU in summer and fall.The total ozone over this region reached its maximum in March and the minimum in September.Continuous observation and analysis of total ozone would help forewarn the change of the environment and climate over Tibetan Plateau.