地理学报 ›› 2014, Vol. 69 ›› Issue (5): 690-696.doi: 10.11821/dlxb201405012

• 气候变化 • 上一篇    下一篇

1981-2010年西藏霜冻日数的变化特征

拉巴次仁, 索朗加措, 白玛   

  1. 西藏自治区气象信息与网络中心, 拉萨 850001
  • 收稿日期:2014-02-20 修回日期:2014-03-30 出版日期:2014-05-20 发布日期:2014-07-30
  • 作者简介:拉巴次仁(1970-),男,西藏拉萨人,学士,工程师,主要从事数据质量控制和气候变化分析。E-mail:623668717@qq.com
  • 基金资助:
    国家自然科学基金项目(41165011)

Spatial and temporal distribution of frost days over Tibet from 1981 to 2010

Labaciren, Suolangjiacuo, Baima   

  1. Meteorological Information and Network Center of Tibet, Lhasa 850001, China
  • Received:2014-02-20 Revised:2014-03-30 Online:2014-05-20 Published:2014-07-30
  • Supported by:
    National Natural Science Foundation of China, No.41165011

摘要: 利用西藏38 个气象站点1981-2010 年的逐日最低气温资料,采用气候倾向率、累积距平、信噪比和R/S 分析等气候统计方法,分析了霜冻日数的年际、年代际、异常、突变等气候变化特征。结果表明:西藏霜冻日数都表现为不同程度的减少趋势,减幅为3.3~14.6 d/10a(37个站P < 0.01);随着海拔高度的升高,霜冻日数减幅在增大。在10a 年际变化尺度上,大部分站点霜冻日数20 世纪80 年代为正距平、21 世纪初为负距平;90 年代霜冻日数以正距平居多。有8 个站点霜冻日数存在突变点,发生在20 世纪90 年代,以1997 年居多。特多霜冻日数发生频数为0~3 次,多发生在20 世纪80 年代;特少霜冻日数频数介于0~4 次,以21 世纪初居多。特多霜冻日数发生频次与经度、纬度和海拔高度的关系不密切,而特少霜冻日数发生频次与海拔高度呈极显著的负相关。

关键词: 年际和年代际变化, 突变, 西藏, 霜冻日数, 异常

Abstract: The annual and decadal variations, anomalous and abrupt change of the frost days are analyzed in this paper, using the daily minimum temperature of 38 stations over Tibet from 1981 to 2010 and modern statistical diagnosis methods, such as linear trend analysis, accumulative anomaly, signal noise ratio and rescaled range analysis (R/S analysis). The results showed that, (1) in recent 30 years, the frost days decreased with a rate of (3.3-14.6) d/ 10a (P<0.01, at 37 stations), and the damping of frost days increased with increasing altitude. (2) In terms of decadal variations, the frost days presented a negative anomaly in the 1980s and a positive anomaly in the 2000s, the positive anomaly range of frost days was larger than the negative anomaly in the 1990s. (3) It was found with abrupt change test that frost days at eight stations had abrupt change, which occurred in the 1990s with the year 1997 having the largest number. (4) The results of R/S analysis showed that changes of frost days had the persistence with a Hurst index larger than 0.5 at most of the stations, and indicated that it will assume a continuous decrease in future and the decreasing rate will became larger. (5) In addition, it was found that the frequency of anomalous (more than normal) frost days was 0 to 3 times and occurred mainly in the 1980s, while the anomalous (less than normal) frost days occurred in the 2000s with a frequency of 0 to 4 times. There is little correlation between altitude (or latitude, longitude) and anomalous more frost days frequency, while altitude has negative correlation with anomalous less frost days frequency.

Key words: annual and decadal variations, climate abrupt, Tibet, frost days, anomalous