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The South china Sea thermohaline structure and circulation

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Acta Oceanologica Sinica 2002年第2期21卷 227-261页

作者： Peter C. Chu, Binbing Ma, Yuchun Chen1. Naval Postgraduate School, Monterey, California, USA2. cold and arid regions environmental and engineering research institute Chinese academy of {2., lanzhou, china Naval Postgraduate School

In this study, we used the Navy' s Master Oceanographic Observation Data Set(MOODS), consisting of 116019 temperature and 9617 salinity profiles, during 1968-1984 to investigate the temporal and spatial variabilities of South china Sea thermohaline structures and circulation. For temperature, profiles were binned into 2.4 monthly data sets from 1968 to 1984 (17 years). For salinity, profiles were binned into 12.climatological monthly data sets due to the data paucity. A two-scale optimal interpolation method was used to establish a three-dimensional monthly-varying gridded data set from MOODS, covering the area of 5°-2.°N and 105° - 12.°E and the depth from the surface to 400 m. After the gridded data set had been established, both composite analysis and the Empirical Orthogonal Function (EOF) analysis (for temperature only) were used to identify the major thermohaline fratures including annual mean, monthly anomalies, and interannual thermal variabilities. The inverted monthly circulation pattern using the P - vector method is also discussed.

关键词： The South china Sea thermohaline structure circulation

THE BALANCE BETWEEN SUPPLY AND DEMAND OF WATER RESOURCES AND THE WATER-SAVING POTENTIAL FOR AGRICULTURE IN THE HEXI CORRIDOR

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Chinese Geographical Science 2002年第1期 24-30页

作者： GAO Qian zhao, DU Hu lin, ZU Rui ping(cold and arid {2. environmental and engineering research institute, the Chinese academy of sciences, lanzhou 730000, P.R.china) cold and arid {2. environmental and engineering research institute the Chinese Academy of SciencesLanzhou 730000P.R.China

The Hexi Corridor is an important base of agriculture development in Northwest china. According to recent statistics, there are 65.94×108m3 of water resources available in the Hexi Corridor. At present, net consumption in development and utilization is 43.33×108m3. Water supply and demand reach a balance on the recent level of production, but loss of evaporation and evapotranspiration is as much as 2..69×108m3. So net use efficiency of water resources is 59%. Based on analyzing balance between water and land considering ecological environment at present, there exists the serious water shortage in the Shiyang River system where irrigation lands have overloaded. There is a comparative balance between supply and demand of water resource in the Heihe River system; and the Sule River system has some surplus water to extend irrigation land. Use of agriculture water accounts for 83.3% and ecological forest and grass for 6.9%. The Hexi Corridor still has a great potential for water saving in agriculture production. Water saving efficiency of irrigation is about 10% by using such traditional technologies as furrow and border dike irrigation and small check irrigation, and water saving with plastic film cover and techniques of advanced sprinkler and drip/micro irrigation etc. can save more than 60% of irrigated water. Incremental irrigation area for water saving potential in the Hexi Corridor has been estimated as 56%-197% to original irrigation area. So the second water sources can be developed from water saving agriculture in the Hexi Corridor under Development of the Western Part of china in large scale. This potential can be realized step by step through developing the water saving measures, improving the ecological condition of oasis agriculture, and optimizing allocation of water resources in three river systems.

关键词： water resources balance between supply and demand water saving potential of agriculture Hexi Corridor

On efficiency of sand-controlling system along the Tarim Desert Highway in Taklimakan Desert

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Journal of Geographical sciences 2000年第2期10卷 141-150页

作者： WANG Xun-ming, DONG Zhi-bao, CHEN Guang-ting, HAN Zhi-wen (cold and arid {2. environmental and engineering research institute, Chinese academy of sciences, lanzhou 730000, china)

As the longest desert highway in china. the 447-kin-long Taklimakan Desert Highway which goes across the Taklimakan Desert was fully opened to traffic in 1996~[1]. The sand-controlling system along the Desert Highway enables the Highway itself to operate properly and creates enormous socio-economic benefits. However, due to delivery time pressure, the sand-controlling system was built in a haste. Lack of studies on sand-controlling system brought deficiencies on design and construction of the sand-controlling system. And with the lapse of time, troubles such as sand deposition on the roadbeds and erosion on roadsides came to surface and caused more serious problems for the traffic routes[1.2.. This paper discusses two forms of the sand-controlling system-the upright fence and the send-covered sand barrier, then analyzes the general benefits of the sandcontrolling system along the Desert Highway.

关键词： sand-controlling system, desert highway Taklimakan Desert

Feasibility Comparison of Reanalysis Data from NCEP-I and NCEP-II in the Himalayas

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Journal of Mountain Science 2009年第1期6卷 56-65页

作者： XIE Aihong REN Jiawen QIN Xiang KANG Shichang State Key Laboratory of Cryospheric sciences Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73oooo China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China

Mt. Everest is often referred to as the earth＇s ＇third＇ pole. As such it is relatively inaccessible and little is known about its meteorology. In 2.05, an automatic weather station was operated at North Col （2.°1′ 0.95＂ N, 86°57′ 48.4＂ E, 652. m a.s.l.） of Mt. Everest. Based on the observational data, this paper compares the reanalysis data from NCEP/NCAR （hereafter NCEP-Ⅰ） and NCEP-DOE AMIP-Ⅱ （NCEP- Ⅱ）, in order to understand which reanalysis data are more suitable for the high Himalayas with Mr. Everest region. When comparing with those from the other levels, pressure interpolated from 500 hPa level is closer to the observation and can capture more synoptic-scale variability, which may be due to the very complex topography around Mt. Everest and the intricately complicated orographic land-atmosphereocean interactions. The interpolation from both NCEP-Ⅰ and NCEP-Ⅱ daily minimum temperature and daily mean pressure can capture most synopticscale variability （r〉0.82. n=83, p〈0.001）. However, there is difference between NCEP-Ⅰ and NCEP-Ⅱ reanalysis data because of different model parameterization. Comparing with the observation, the magnitude of variability was underestimated by 34.1%, 2..5 % and 2..1% for NCEP-Ⅰ temperature and pressure, and NCEP-Ⅱ pressure, respectively, while overestimated by 44.5 % for NCEP-Ⅱ temperature. For weather events interpolated from the reanalyzed data, NCEP-Ⅰ and NCEP-Ⅱ show the same features that weather events interpolated from pressure appear at the same day as those from the observation, and some events occur one day ahead, while most weather events and NCEP-Ⅱ temperature interpolated from NCEP-Ⅰ happen one day ahead of those from the observation, which is much important for the study on meteorology and climate changes in the region, and is very valuable from the view of improving the safety of climbers who attempt to climb Mt. Everest.

关键词： Mt. Everest NCEP/NCAR (NCEP-Ⅰ) NCEP-DOE AMIP-Ⅱ (NCEP-Ⅱ) daily minimumtemperature (DMinT) daily mean pressure(DMeanP) High Himalayas

Impacts of Yulong Mountain Glacier on Tourism in Lijiang

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Journal of Mountain Science 2006年第1期3卷 71-80页

作者： YUAN Lingling LU Aigang NING Baoying HE Yuanqing cold and arid {2. environmental and engineering institute Chinese Academy of Sciences Lanzhou 730000 China The institute of Tibet research Chinese Academy of Sciences Beijing 100029 China

The glacier on the Yulong Mountain is one of the most important attractions in Lijiang, Yunnan, china. But it keeps retreating these years due to global warming, which is bound to influence regional tourism significantly in Lijiang. This study estimates the effects of the glacier retreat of the Yulong Mountains on tourism there. Primary data were collected through a visitor survey including demographics, motives, lengths of stay, and opinions about each tourism resource from tourists to Lijiang, as well as questions about which scenic spot（s） they had visited or would visit, how much they expended per day during their visit and how their visiting behavior would be changed upon the hypothesis that the glacier would disappear. These data were used to analyze the proportion of the contribution of glacier to the tourism in Lijiang and estimate the impact of glacier on the regional tourism quantitatively. According to the survey, it could be concluded that three quarters of the tourists to Lijiang were interested in the Yulong Mountain glacier, indicating that the glacier possesses notable appeal for sightseeing tourists. The results of our analysis showed that about 689,013-1,508,2.7 tourists, accounting for 19.63-42.97 % of the total 3,510,000 domestic tourists to Lijiang in 2.04, would not come to Lijiang in the absence of the glacier, resulting in a possible direct economic loss of 84,382.508-184,713,011 USD （viz. 700,374,82.-1,533,117,993 RMB） and a markedly decrease in the attraction radius.

关键词： Glacier retreat tourism economic impact appraisal Lijiang Yulong Mountain china

Preliminary reconstruction of the desert and sandy land distributions in china since the last interglacial period

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Science china Earth sciences 2004年第z1期47卷 89-100页

作者： CHEN Huizhong, SU Zhizhu, YANG Ping & DONG GuangrongKey Laboratory of Desert and Desertification, cold and arid {2. environmental and engineering research institute, Chinese academy of sciences, lanzhou 730000, china State Key Laboratory of Loess Quaternary Geology, institute of Earth Environment, Chinese academy of sciences, Xi’an 710075, china institute of Loess Plateau, Shanxi University, Taiyuan 030006, china 1. Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 2. State Key Laboratory of Loess Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 3. institute of Loess Plateau Shanxi University 030006 Taiyuan China

The desert and sandy land are the products of arid climate. The spatial distribution of modern deserts and sandy land in china and their relation to climate show following characteristics: arid and hyper-arid desert zones, at isohyet of less than 2.0 mm, are dominated by mobile dunes; semi-arid steppe and arid desert steppe with the precipitation between 2.0?00 mm, are dominated by semi-fixed and fixed sand dunes; the precipitation of sub-humid forest grassland and humid forest zones with scattered fixed sand land is higher than 400 mm. With this as reference, in combination with considerable amount of paleoclimatic data in desert regions and adjacent regions, the distributions of desert and sandy land in china during the last intergla-cial period, the last glacial maximum (LGM), and the Holocene megathermal, were preliminarily reconstructed. The results compared with that of today show that the distribution of desert and sandy land in china was greatly dwindled during last interglacial period, and the mobile dune area was about two-thirds of that of today's, but greatly expanded during LGM. However, the dwindling area of desert and sandy land in the Holocene megathermal was smaller than that in the last interglacial period. The forcing mechanism was mainly related to the changes of East Asian winter and summer monsoon, south-northward swing of the westerlies and the variations of the Qinghai-Tibet Plateau monsoon intensity caused by global climate changes during the cold and warm intervals since the last interglacial period.

关键词： the glacial-interglacial period, desert, sandy land, spatial distribution.

Processes and modes of permafrost degradation on the Qinghai-Tibet Plateau

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Science china Earth sciences 2010年第11期53卷 150-158页

作者： WU JiChun,SHENG Yu,WU QingBai & WEN Zhi State Key Laboratory of Frozen Soil engineering,cold and {2. regions environmental and engineering research institute,Chinese academy of sciences,lanzhou 730000,{12. 1. State Key Laboratory of Frozen Soil engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Climate warming must lead the mainly air temperature controlled permafrost to *** on the numerical simulation,the process of permafrost degradation can be divided into five stages,i.e.,starting stage,temperature rising stage,zero geothermal gradient stage,talic layers stage,and disappearing stage,according to the shape of ground temperature *** on the Qinghai-Tibet Plateau (QTP) is generally considered a relic from late Pleistocene,and has been degenerating as a whole during *** to spatial-temporal compensation,the present thermal state discrepancy of permafrost in different areas on the QTP may correspond with their degradation *** the QTP,permafrost in the high and middle mountains belongs to temperature rising stage,the permafrost thermal state is transiting from late rising temperature stage to zero geothermal gradient stage that is distributed in the *** that is in a zero gradient stage mainly appears in the high plateau and valley,whereas the transition from zero gradient stage to talic layers stage of permafrost is located in the vicinity of the lower limit of permafrost,and permafrost is disappearing from margin of perennially frozen *** are two modes of perennially frozen ground thawing,thawing from top to bottom and thawing from bottom to top *** the temperature rising stage,when the heat flux in the perennially frozen soil layer is less than that in the unfrozen soil underlying frozen soil layer,the geothermal flux is partly used to thaw the base of permafrost,and permafrost thaws from bottom to *** the decrease of thermal gradient in the perennially frozen ground,the heat that is used to thaw permafrost base increases,and geothermal heat will be entirely consumed to thaw the base of permafrost until the temperature gradient reaches zero thermal gradient *** the other hand,the disappearance of permafrost may be delayed by "thermal offset" and "seas

关键词： Qinghai-Tibet Plateau permafrost degradation process degradation stage degradation mode

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Identification and analysis of root causes of desertification in semi-arid region of china──a case study from Ejin Horo Banner, Inner Mongolia

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Journal of Geographical sciences 2000年第2期10卷 108-118页

作者： CHEN Jie, GONG Zi-tong, GAO Shang-yu (institute of Soil Science, Chinese academy of {2., Nanjing 2.0008, china, cold and arid regions environmental and engineering research institute, Chinese academy of {2.,lanzhou 730000, china)

A case study on the driving forces of desertification in the semi-arid region was carried out in the Ejin Horo Banner of Inner Mongolia. The occurrence and development of desertification were demonstrated and its driving factors were identified and analyzed. The results obtained indicated that over-reclamation of land overgrazing and denudation of natural vegetation cover were immediate and dominant factors causing land vulnerability to desertification. For a better understanding of the deep-rooted causes of the inappropriate land use and agricultural practices, the problems arising from various socioeconomic facets were comprehensively discussed.

关键词： desertification, land degradation send-arid region human activities, climatic variation

Effect of Altitude and Latitude on Surface Air Temperature across the Qinghai-Tibet Plateau

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Journal of Mountain Science 2011年第6期8卷 808-816页

作者： WANG Keli SUN Jia CHENG Guodong JIANG Hao cold and arid {2. environmental and engineering research institute Chinese Academy of Sciences Lanzhou 73oooo China National Natural Science Foundation of china Beijing 100085 China Graduate University of Chinese academy of sciences Beijing ~ooo49 China

The correlation between mean surface air temperature and altitude is analyzed in this paper based on the annual and monthly mean surface air temperature data from 106 weather stations over the period 1961-2.03 across the Qinghai-Tibet Plateau. The results show that temperature variations not only depend on altitude but also latitude, and there is a gradual decrease in temperature with the increasing altitude and latitude. The overall trend for the vertical temperature lapse rate for the whole plateau is approximately linear. Three methods, namely multivariate composite analysis, simple correlation and traditional stepwise regression, were applied to analyze these three correlations. The results assessed with the first method are well matched to those with the latter two methods. The apparent mean annual near-surface lapse rate is -4.8 ℃ /km and the latitudinal effect is -0.87 ℃ /°latitude. In summer, the altitude influences the temperature variations more significantly with a July lapse rate of -4.3℃/km and the effect of latitude is only -0.2.℃ /°latitude. In winter, the reverse happens. The temperature decrease is mainly due to the increase in latitude. The mean January lapse rate is -5.0℃/km, while the effect of latitude is -1.51℃ /°latitude. Comparative analysis for pairs of adjacent stations shows that at a small spatial scale the difference in altitude is the dominant factor affecting differences in mean annual near-surface air temperature, aided to some extent bydifferences of latitude. In contrast, the lapse rate in a small area is greater than the overall mean value for the Qinghai-Tibet Plateau （5 to 13℃ /km）. An increasing trend has been detected for the surface lapse rate with increases in altitude. The temperature difference has obvious seasonal variations, and the trends for the southern group of stations （south of 33 o latitude） and for the more northerly group are opposite, mainly because of the differences in seasonal variation at low altitudes. For

关键词： Qinghai-Tibet Plateau Surface airtemperature Vertical lapse rate Altitude Latitude