【摘要】 <正> 利用树木年轮来推断古气候,是研究气候变化的一种有效途径。一个好的树木年轮序列相当于一部可靠的气候变化史册。特别是对一些荒凉的高山地区,其使用意义和价值更大。年轮宽度能较好地反映大旱、低温等异常气候。一九八一年中日联合考察队对天山博格达峰地区进行冰川考察,采集了一棵年轮为150年左右的天山云杉(PiceaTianshanensis),对这棵树的年轮宽度序列分析如下。更多还原

【Abstract】 This paper discussed the relation of climatic elements to the tree ring using the tree ring data for 147 years in the Bogda area, Tian Shan. After analysis of the climatic variations in the last 150 years, the authors found that there were three dry and wet periods i.e. the three wets in 1841-1854, 1869-1877, 1905-1941 and the three drys in 1855-1868, 1878-1904 and 1942-up to present. Further detailed analysis reveals that the climate tended to be drier and drier in the past 150 years and reached the climax in 70 s and turns to wet in early 80 s. Moreover, the duration of dry spells is becoming longer and longer (the first dry spell lasted 13 years, the second 24 years and the third 34 years ) . The wettest period happened in the first half of this century, and the driest in the 70 s.Because this result agrees fundamently with that of the surrounding regions, we deduce that since the little ice age, there might be four dry and wet spells of climatic variations in this region. The earliest one might happen near the end of 17th century up to beginning of 18th century.更多还原