摘要
自1991年起对玻利维亚的查卡尔塔亚冰川(16°S,雷亚尔山)和1995年起对厄瓜多尔的安蒂扎纳15号冰川(0°,厄瓜多尔)的质量平衡作了连续监测。在冰川消融区,按一个月尺度测量了质量平衡,提供了有关两种不同热带环境中季节性变化模式的有意义的详细数据。这两个地区最近40年来都有关于冰后退的断断续续的报道。这些资料指出,这10年来冰川退缩明显加速了;消融速率已比前几十年高3～4倍。以前在秘鲁北部测量3条冰川的变动,使我们可以假定:安第斯山脉热带山段冰川退却的速率在20世纪70年代增高了。小规模冰川(<1km)的现状特别令人担忧,象查卡尔塔亚等许多冰川将在今后10年内消失。已经收集的资料证明,在ENSO(厄尔尼诺南方涛动)变暖期消融作用显著增强,而在变冷期(拉尼娜)减弱。自20世纪70年代晚期以来,变暖事件变得更频繁、更强烈了。可以假定,它们已对安第斯山脉中部现代冰川退缩起了显著作用,还有全球气候变暖的影响。
Mass balance has been continuously monitored on Chacaltaya Glacier (16°S, Cordillera Real, Bolivia) since 1991, and on the Antizana Glacier 15 (0°, Ecuador) since 1995. In ablation areas, mass balance has been surveyed on a monthly scale, providing interesting details about the seasonal pattern in 2 contrasting tropical environments. Intermittent information about ice recession exists in both regions for the last 4 decades. The data point to a clear acceleration during glacier decline during this decade; ablation rates have been 3-5 times higher than during the former decades. Fluctuations measured before on 3 glaciers in northern Peru, allow the assumption that the rate at which the glaciers retreated in the tropical Andes increased in the late 1970s. The present situation is particularly dramatic for the small-sized glaciers (< 1 km2) and many such as Chacaltaya, could disappear in the next 10 years. As evidenced by the data collected, ablation increases significantly during the warm phases of ENSO (El Nino) and decreases during the cold phases (La Nina). Warm events becoming more frequent and intense since the late 1970s, it can be assumed that they have played an important role in the recent glacier decline in the central Andes, together with the global warming.
