同位素温标的显著性水平

The Significance Level of Stable Isotope Thermometer of Precipitation in China

在中国大气降水年均同位素δ值与年均地面气温之间，在α为0．01的显著性水平存在直线关系，氢同位素温标为3.1‰/℃，氧同位素温标为0．36‰/℃。但是，在月均占值与月均地面气温之间的关系比较复杂：①在中国北方，氧同位素温标由西向东为0．65～0．10‰/℃。相关指数自西向东为0．73～0．14，显著性水平均达到。为0．01；②在中国南方，显著性水平虽达α为0．01，但是温标皆小于零，相关指数多数小于0．5；③南京、武汉、长沙、拉萨、西安和太原等台站，月均同位素占值与月均地面气温之间无相关性。

According to multi-year average values from 32 stations in Chinese network, a good linear relationship with the significance level α= 0.01 exists between δ-values of precipitation and surface air temperature, The H-isotope thermometer is about 3.19‰/℃, and the O-isotope thermometer is about 0.36 9‰/℃. The stations with the significance level of α= 0.01 and the monthly isotope thermometer 〉 0 are located in North China （to the north of the Qinling Mountain and the Huaihe River） with latitude from 37°N up to larger than 47°N, where the determination coefficients are 0.41≤R^2≤0.73 in the west stations and 0.14 ≤ R^2≤ 0.56 in the east stations and the monthly O-isotope thermometer ranges from 0.10 to 0.65 ‰/1℃. The stations with the significance level of α= 0.01 and B 〈 0 are located in South China （to the south of the Qinling Mountain and the Huaihe River） with low latitude, i. e. from latitude of 32°N down to 20°N, where the determination coefficients are mostly R^2〈 0.5 and the monthly O-isotope thermometers are wholly 〈 0. Some of the stations withα = 0 and 0. 0002 〈 R^2〈 0.14 and the monthly O-isotope thermometers range from - 0. 005 to 0.2, e.g. , stations of Nanjing, Wuhan, and Changsha are located in the middle and lower reaches of the Yangtze River with latitude from 28°N to 33°N, and stations of Lhasa, Xi＇an and Taiyuan belong to the local climate of mountain valley, all of which show that variations in monthly δ^18O are not related to monthly surface air temperature.