Yulong Snow Mountain Glaciers and Environmental Observation Station, Cold and Arid Region Environment and Engineering Research Institute, Chinese Academy of Sciences
Based on the meteorological and hydrologic data in the Lijang basin from 1979 to 2006, variational trend and characteristics of climate change and its effect on runoff in Yanggong increasing trend in runoff was more significant than the increase in precipitation in the study area. That was the synactic results of variation of groundwater, ice-snow meltwater and precipitation caused by global climate change. Under the background of global warming, the past 28 years have witnessed the fact of significant temperature upward with fluctuation in Lijiang basin.According to preceding analysis, the increase of winter temperature was the most at the level of 0.55 ℃/10a.
The annual precipitation varied with a slightly upward trend in the past 28 years. However, there are notable differences between different seasons. Precipitation increase occurred in spring and summer,whereas the decrease occurred in autumn and winter.In addition, spring experienced the most significant amplitude of variation; winter came next. Summer and autumn experienced the lowest. The streamflow at Yanggong River showed a significant increasing trend in the past 28 years, of which increase rate is greater than precipitation. During During the four seasons, spring experienced the most significant increase and autumn experienced the smallest.The tendency of runoff change comes in line with the precipitation in spring and summer, but the two go in opposite tendency in summer and winter. In winter and spring, the recharge of runoff by precipitation is little. Correlation analysis proved that precipitationis the most important factor affecting runoff in thestudy area embodied in rainy season. Nevertheless, the effect of temperature on runoff especially in non-flood season should not be neglected(He et al, 2010).
Based on observed mass balance and meteorological data since September 2008 and ablation data by the expedition team of Tibetan plateau from June to August 1982 at Baishui Glacier No. 1 region, we analyzed the spatial and temporal changes of degree-day factor (DDF) of the Baishui Glacier No. 1 following the changes of space, time, and temperature, which lays a theoretical foundation to establish DDF model. The results indicate that the melting DDF of ice showed a significant downward trend with rising temperatures, and larger value of DDF only appeared at low temperature conditions. A larger value of DDF appeared in the high altitude areas, and as altitude rises, the value of DDF increased. The snow DDF is lower than the DDF of ice, and the DDF is higher in temperate glaciers than those in other glaciers. The melting DDF of snow has a more obvious seasonal variation than the melting DDF of ice(He et al,2010).
Alpine glaciers usually feature with best hydrothermal condition in mountain climate, and present beautiful glacier scenery, various glacier landforms, rich biodiversity, and easier accessibility, compared with continental glaciers or ice sheets. Nevertheless, Alpine glaciers are more sensitive to climate warming, and climate warming has seriously affected Alpine glaciers and surrounding environment. The quality and attractiveness of Alpine glaciers to tourism has been and will continue to be diminished with tourists’ visitation and local economic development. At present, it has become a primary problem that Alpine glacier tourism adapts to climate warming. Based on this reason, the purpose of this article is to take Baishui Glacier No. 1 as an example to outline the possible impacts of climate warming on Alpine glacier tourism and put forward some adaptive measures and strategies aligned with climate warming. Specific measures are as follows: (1) optimize the space layout of glacier tourism area; (2) improve glacier tourism and environmental protection planning; (3) adopt multidimensional protective measures; (4) strengthen scientific research of glacier and environment protection; (5) develop glacier tourism products by multi-directions; (6) integrate regional tourism resources; (7) reinforce public environmental education (Wang et al,2010).
Aerosol and snow samples were collected at ablation zone of Baishui Glacier No. 1,Mt. Yulong, from May to June, 2006. The concentrations of Cl-, NO3-, SO42-, Na+, K+, Mg2+, andCa2+ were determined by ion chromatograph both in aerosol and snow samples. The average total aerosol loading is 25.45 neq·scm-1, NO3- and Na+are the dominant soluble ions in the aerosol, accounting for 39% and 21% of average total aerosol loading, respectively. Monsoon circulation reduces the concentration of most ions, indicating that wet scavenging is effective for aerosol particles. In snow samples, SO42- andCa2+ are the dominant anion and cation, respectively.A lower Na+/Cl- ratio was found in fresh snow samples compared to the higher ratio that was found in aerosol samples. Analyzing the difference in SO42- and NO3- in air and fresh snow indicated that the aerosol was influenced by local circulation, but the components in fresh snow samples were from long-distance transport. Enrichment of NO3- in aerosol samples is attributed to motor exhaust emissions from tourism by calculating theSO42-/NO3- ratio in aerosol and fresh snow samples. The temporal variation and correlation coefficients between soluble species in aerosol samples suggest that Cl-, Na+ and K+ come from sea-salt aerosol, and SO42-, Mg2+ and Ca2+ are from continental crust sources(Zhang et al,2010).
Changes of climate, glaciers and runoff during the last several decades in China’s monsoonal temperate glacier region have been studied. Temperature has increased in a fluctuating manner during the last several decades, and temperature rise has accelerated since the 1980s. Net accumulation of Dasuopu ice core has consistently declined, and the precipitation decrease was also obvious from the end of 1970s through the middle 1980s, and particularly after the 1990s in China’s monsoonal temperate glacier region. As a response to climate change, eight monsoonal temperate glaciers were stationary or advancing between the 1900s–1930s and the 1960s–1980s, and were in retreat from the 1930s to the 1960s and from the 1980s to the present. Ablation is heavy in the glacier tongue areas, and the mean ablation water equivalent in Hailuogou glacier during 1990/91–1997/98 was 876 mm more than that in 1982/83. Ablation depth on the exposed ice area increased by 1.4 m/a over the period 1983/84–1990/91. Mass balance records also show that glaciers suffered a constant mass loss of snow and ice, and the accumulated mass balance in Hailuogou basin and Baishui glacier No.1 was -10.83 m water equivalent in the past 45 years, and -11.38 m in the past 52 years. As glaciers become shorter, narrower and thinner under the background of climate warming, changes of internal and upper surface morphology also occurred, providing evidence of the response to climatic warming in recent years. Local hydrological and climatic data demonstrated that, in Yanggong basin during 1979–2003 and Hailuogou basin during 1988–2004, runoff from the glacier areas has been increasing both seasonally and annually. Overall, it is clear that China’s monsoonal temperate glaciers are losing mass and are retreating under the background of climate warming. China’s monsoonal temperate glaciers are losing mass and are retreating under the background of climate warming. Changes of glaciers and runoff have responded to climate fluctuations in the last several decades, but it is difficult to quantitatively evaluate the relationship owing to the sparse spatial coverage of reliable evidence and the limited available longer term data. As the results of glacial retreat, floods, mudflows and rock falls caused by meltwater and storms will affect traffic, tourism and the wider economic development of the monsoonal temperate glacier region.Further changes of the water cycle in a warming climate could lead to serious water and soil erosion in high altitude zones, and may threaten soil systems and the ecological environment. Climate warming is one of the most critical challenges of our time, and its impact on glaciers and hydrological systems in West China demands continued study(Li et al,2009).