从我国玉龙雪山典型温冰川王白水1号冰川不同区段表面融水，新近积雪和冰川补给河水采样分析结果表明，雪线以上降水中的稳定同位素和离子含量比雪线以下为高，低海拔河水比高海拔融水的氧同位素浓度为低，可能在来源上存在着差异，这种分布特征说明本温冰川区局部大气环流情况随高度而不同，有可能存在季风气候区所特有的“降水量效应”或“季节性效应”。冰川不同水体内离子浓度变化说明，冰川融水与地壳表面接触时间越久，其中的可融性离子浓度就越高，此外也与当地基岩岩性密切相关。冰川水化学的空间分布反映出温冰川化学溶解作用和物理活动性都比较强。小冰期以后气候变暖，玉龙山冰川后退的幅度也比较大。实测资料表明，50年代以来气候大体以11 a～12 a的周期波动，受气候波动的控制，冰川时进时退，变化幅度不同。玉龙山冰川在经历了1980～1990年的后退以后，最近又显示出前进趋势。在大部分时期内，除非突然出现全球大幅度变暖的情况，冰川受气温和降水非同步变化的制约，在总体趋势上是比较稳定的，不会很快消失，也不会突然大幅度前进。%Mt. Yulong is the southmost present glacialized area in Eurasia,where there are 19 typical sub-tropics temperate glaciers above 4000m a. s. l., formed under the climate of south-west monsoon. In the summer of 1999, investigations of glacial hydro-chemistry were carried out at the largest glacier, Baishui No. 1 and 23 samples were collected from new accumulated snow, summer rain, glacial meltwater and glacier-feeding river at the different levels of the glacier. Chemical analysis of these samples show that isotopic and ionic contents of precipitation above the equilibrium line (4 800 m) is much higher than that below it, implying that the atmospheric vapor for precipitation came from different sources and a ”precipitation effect” or ”monsoon effect” may exist in this typical monsoon-climate region. Ionic contents of glacial meltwater were increasing with the decrease of elevation as a result of longer-time contact with the earth's surface. The highest content of Ca2+ in all collected samples is closely related to local bedrock which mainly compose of limestone. Glacial hydro-chemistry of the studied area is characterized by a distinct spatial variability in various water bodies because of stronger physical and chemical activity of the temperate glacier, which differs from those of the continental glaciers.rn Glaciers have greatly retreated after the Little Ice Age because of warming of the climate. The recent 50 year climatic data at Lijiang, the closest meteorological station to Mt. Yulong, indicates that there are 2～3 year periodic changes for the local temperature and apparent 11～12 year periodic cycles for precipitation, showing a corresponding pattern with that in northeastern part of India. During the most recent half-century, glaciers in Mt. Yulong have alternately retreated and advanced, with smaller amplitudes. According to the trend of local climatin last 50 years and recent observation at the glacier Baishui No. 1, the glaciers in Mt. Yulong start to advance in 1998 after a continuous retreat stage between early 1980's and late 1990' s. However, as a result of a negative relation between temperature and precipitation in most cases of this region, the glaciers will keep a relatively stable state in the future overall trends, except for a case of abrupt large-scale global warming.
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