Abstract: The two ice caps of Svartisen, at the latitude of the Arctic Circle in Norway, supply 60 glaciers, ranging in size from > 50 to < 1 km2. Until the last two decades of the 19th century, the glaciers remained close to their maximum recent (Little Ice Age) size. In response to the prevailing 20th century climate, they have become smaller, but the changes have varied between glaciers. Climatic factors have not been the sole control of the variations. The response times of small, steep glaciers are shorter than those of the longer, more gently sloping outlet glaciers. Topographic factors may moderate the response of individual glaciers to climate. The 20th century mass balance of several of the larger glaciers was dominated by calving into marginal lakes. The mass balance of Engabreen, the largest outlet of the western ice cap, has been measured every year since 1970 and the cumulative balance to 2008 was a gain of 22.7 m water equivalent. Although the pattern of annual variations probably applies to the other glaciers of Svartisen, it does not indicate their actual changes (gain or loss). Thus, the Engabreen record is of little utility in water resource planning for the whole area.
Abstract: Based on the meteorological and hydrologic data in the Lijang (丽江) basin from 1979 to 2006, variational trend and characteristics of climate change and its effect on runoff in Yanggong (漾弓) River were examined in the study. The results show that the temperature have significantly increased in the drainage basin during the past 28 years. The average temperature increased markedly from 1979 to 2006, and the increase of temperature in winter was higher than those in other seasons. The annual precipitation varied with a slightly upward trend in the same period, suggesting that the increase mainly occurred in spring and summer while the decrease occurred in autumn and winter. The streamflow at Yanggong River showed a significant increasing trend. During the four seasons, spring experienced the most significant increase, and autumn experienced the smallest. On the basis of the above study, we found that the 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.
Abstract: 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 (白水) 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.
Abstract: The seasonal and inter-annual variations of pH and EC (electrical conductivity) at Yulong (玉龙) Snow Mountain, Lijiang (丽江) City, are sensitive to precipitation variations and are important indicators of the atmospheric environment. The pH of summer rainfall at Lijiang City ranges from 6.7 to 7.4, and alkaline mineral salts dominate the variations of rainfall acidity. pH values in the shallow firn profile at Baishui (白水) Glacier No. 1 range from 5.6 to 6.3, and EC values from 2.4 to 7.3 μs/cm. The ranges are lower than those in other firn cores from China because of stronger elution and the influence of marine aerosols. This indicates that environmental records from a monsoonal temperate glacier differ from those at continental glaciers.
Abstract: 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 (白水) 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.
Abstract: Under the background of significant climate warming since the 1980s, the glaciers in China's monsoonal temperate glacier region respond to the warming intensely. Based on the glaciohydrological observations at some typical glaciers from Mts. Yulong (玉龙) and Gongga (贡嘎) of Hengduan (横断) Mountains Range in the southeastern Tibetan plateau, the glaciohydrological changes in the temperate glacier region since the 1980s were investigated. First, the glacier terminus exhibited an accelerating retreat. Second, as the glacier area subject to melting has increased and the ablation season has become longer due to the warming, the ablation of glacier enhanced, leading to increasing contribution of meltwater to annual river discharge. Third, surface topography of small temperate glacier may be changed significantly by crevasses and ruptures developed in the accumulation zone and ice collapse events in the ablation zone. The observed results may indicate a signal that the survival of glaciers in China's monsoonal temperate glacier region is being threatened by today's climate warming.
Abstract: High topographies, such as the Tibetan plateau (TP) in China, have been considered as the sensitive areas in response to global climate change. By analyzing the relationship between warming structure and altitude (1 000-5 000 m) in the TP and its vicinities using the 46-year January mean observed temperature data, we found that there was a significant altitude effect of temperature warming onset time (mutation time) on the plateau and the neighboring regions: the higher the altitude, the later the climate warming happens, and vice versa. There also seems a slight altitude effect on warming magnitude: the higher the altitude, the less the warming magnitude. Therefore, the temperature warming in the high altitude area of the TP (below 5 000 m) responds to global warming less sensitively than the low-altitude neighboring areas both in onset time and magnitude, which may be mainly caused by high albedo and large thermal capacity of the ice/snow cover on the higher part of the plateau and possible heat island effect in the lower part of the plateau.
Abstract: Aerosol and snow samples were collected at ablation zone of Baishui (白水) Glacier No. 1, Mt. Yulong (玉龙), from May to June, 2006. The concentrations of Cl-, NO3-, SO42-, Na+, K+, Mg2+, and Ca2+ 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- and Ca2+ 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 the SO42- /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.
Abstract: The causes and consequences of soil erosion in Madagascar have been the focus of recent environmental debates. The Betsiboka, Madagascar's largest river stretching 600 km from the high central plateau to the northwest coast on the Mozambique Channel, is a major conduit for transporting lateritic soils and sediments derived from the highlands of Central Madagascar to the sea. These entrained lateritic sediments color the river a blood-red hue, as if the life of the island is being drained away. In this study, Landsat visible and near infrared spectral bands are used to map the underwater sediments especially under the sea and in the interface between seawater and freshwater. Band color composites, single bands and band ratios are used to improve the detection of underwater sediments including sand bars and delta lobes. We show the evolution of the bay, coastline, delta, and change detection results derived from Landsat satellite images recorded in 1973, 1989, 1999, 2000 and 2003, respectively. Results indicate that sedimentary transport and suspension in Bombetoka Bay has significantly changed during the past 30 years, with a dramatic increase in the amount of sediment moved by the river, and deposited in the estuary and in offshore delta lobes. These changes have adversely affected agriculture, fisheries, and transportation for one of Madagascar's largest ports. The changes are attributed to increased erosion following large-scale deforestation, bush fires, and overgrazing in the river basin.
Abstract: Up to now, there were no systematic studies of geochemistry and isotopic age for the Yixian (义县) fluorite deposit, western Liaoning (辽宁) Province, China. Based on the analysis of metallogenic geological setting, we studied the REE, Rb-Sr and Sm-Nd isotopes. The chondrite-normalized REE patterns of fluorite are characterized by moderate LREE depletion (LREE/HREE=0.95-3.57, (La/Yb)N=0.08-2.84) and enrichment of Sr (146×10−6-596×10−6) and moderately positive Eu anomalies (δEu=1.10-1.34), which are similar to those of the host Mesoproterozoic carbonate rocks. The fluorite display (87Sr/86Sr)t=−0.708 5, (143Nd/144Nd)t=−0.511 785, and εNd(t)=−12.8, which are similar to those of the host Mesoproterozoic carbonate rocks and volcanic rocks of Middle Jurassic Lanqi (蓝旗) Formation. The REE and Sr-Nd isotope geochemistry suggest that the source of the ore-forming material may be the volcanic rocks of Lanqi Formation and host carbonate rocks. The Sm-Nd isochron age of 154±14 Ma (MSWD=0.23) indicates that the Yixian fluorite mineralization nearly corresponds to the period of Lanqi Formation. Based on the integrated geological and geochemical studies, coupled with previous studies, we suggest that Yixian fluorite deposit formed in the extension setting of postcollisional stage and may be attributed to the partial melting of ancient basaltic rocks in the lower crust induced by underplating of basic magma and to the reaction between the F-rich ore-forming fluids and the host carbonate rocks.
Abstract: The Lunnan (轮南) low uplift is a complex basin that is situated in northwestern China. This area had undergone a range of tectonic events, and there are multi-production zones and reservoir types. Also, heavy oil, common black oil, volatilization oil, condensate oil and natural gas are approximately under the same stratum pressure grads and geothermal grads. The east Lunnan low uplift is mainly composed of condensate oil and natural gas, the middle part has many types of petroleum and the west part mostly has heavy oil. The petroleum geochemistry may be the principal reason for the great difference of the oil and gas characteristics. The heavy oil in the west part is established by the biodegradation and mixing effect. The mixing effect in the middle part produced the complex petroleum distribution, and the oil cracking effect and mixing effect, or air cutting effect in the east part is proof of the existence of the industrial condensate gas reservoir and waxy oil. Understanding of the complex petroleum reservoir can further supervise the development of petroleum exploration in the Lunnan low uplift.