Welcome to Journal of Agriculture,

Journal of Agriculture ›› 2015, Vol. 5 ›› Issue (1): 130-133.doi: 10.11923/j.issn.2095-4050.2014-xb0407

Previous Articles     Next Articles

Extreme Temperature Variability in Tianshui over the past 63 years

  

  • Received:2014-04-18 Revised:2014-04-18 Accepted:2014-06-16 Online:2015-01-29 Published:2015-01-29

Abstract: Evaluation of extreme temperature changes in Tianshui under global warming is studied based on annual extreme temperature data from 1951 to 2013. To better understand the variability and long-term trend of extreme temperature, various mathematical statistics methods, including the climate tendency rate, climate tendency coefficient, percentile threshold value method and slidingT -test method, have been used. Results indicate that annual extreme temperature showed a significant increase trend over the past 63 years. The extreme high-temperature rate of increase is estimated as 0.2℃/10 a, while the extreme low-temperature increased by 0.3℃/10 a, which are all statistically significant at 99% confidence level. The threshold values of temperature extremes have been determined using the percentile threshold value method, we find that the difference between the extreme high-temperature (extreme low-temperature) and the corresponding threshold value increased (decreased) with the length of time series. The temporal characteristics of extreme hightemperature and extreme low-temperature trends are analyzed by using sliding T-test method. There is no significant abrupt change in extreme low-temperature at 99% confidence level. In contrast, the extreme hightemperature changes abruptly in 1983 and 1993.