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North West Ili in Xinjiang Tianshan southern slope, Huocheng, Yining County, Nilka County, three county administrative district eight sampling points Schrenk spruce tree ring data, developed a tree-ring width chronology. Through comparative analysis of the relevant parameters, suggesting that watershed chronology may contain more climate information. Using tree-ring climatology basic principles and methods of analysis: the study area and the area tree ring width chronology last year July to current June last year July-August average rainfall and average maximum temperature correlation better, highest single correlation coefficients were 0.664 (α = 0.00000025) and -0.624 (α = 0.00000184). Taking into account rainfall and average maximum temperature for the continuity Schrenk spruce tree growth effects of stepwise regression analysis, the study area was established last year in July to current June precipitation and July-August average maximum temperature reconstruction equation , the cross-examination proved equation is stable. Using equation reconstructed the past 250 years of precipitation and average maximum temperature sequence. By precipitation and average maximum temperature reconstruction sequence analysis, the following conclusions: (a) western Xinjiang Yili North Tianshan southern slope last year in July to current June rainfall in July-August last year the average maximum temperature District Schrenk spruce tree-ring growth and have a great impact, both with a clear physiological significance of trees. (2) to study the area near 256a last year in July to current June precipitation has gone through 10 stages and nine dry humid phase. One of the most humid stage is 1869-1877 years, compared with 7.9 per cent above normal mean for many years; most arid phase is 1757-1766 years, compared with 12.7 per cent below normal mean for many years; longest partial wet stage is 1949-1971 years, the last 23 years , 6.0% above normal than average for many years; longest dry stage is 1972-2000, continued for 29 years, compared with 1.7 per cent below normal mean for many years. To study the area near 255a July-August average maximum temperature has gone through eight stages and eight warmer colder phase. One of the most warm moist stage is 1853-1869 years, higher than the historical average of 0.6 ℃; coldest stage is 1870-1876 years, lower than the historical average of 0.8 ℃; longest warm stage is 1912-1947 years, lasted 36 years, higher than the historical average of 0.2 ℃; longest colder phase 1888-1911, the last 24 years, lower than the historical average of 0.1 ℃. (3) on the precipitation, the near-256a to study the drought years of 7a (2.7%); dry years as 55a (21.5%); regular annual number 127a (49.6%); humid number of years 60a (23.4% ); humid number of years 7a (2.7%). Partial wet years (including wet years) than dry years (including drought years). Driest year was 1753, compared with 50.0 percent less than normal years average; wettest year was 1941, compared with 40.0 percent above normal mean years. On average maximum temperature, the study area near 255a to the normal number of years 199a (78%); warmer number of years 27a (10.6%); colder number of years 29a (11.4%). From the extreme perspective, the average maximum temperature maximum in 1916, was 31.6 ℃, warm 1.8 ℃; average temperature minimum in 1875, was 27.8 ℃, cool 2 ℃. (4) the study area last year in July to current June precipitation, in 1807, 1831, 1911, 1971 mutation, which in 1807, in 1911 by a number of mutations in the small, 1831, 1971, from less to more mutations. At the 0.05 level of significance has 2.6a, 3.3a, 3.4a, 8.1a, 17a quasi-periodic variation. July-August average maximum temperature, in 1778, 1803, 1831, 1854, 1871, 1909 mutation, which in 1778, 1831, 1871, from high to low mutation, 1803, 1854, 1909 from low to high mutation. Significant at the 0.05 level of quasi-periodic variation with 2.7a.
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