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Precipitation variability in central Himalayas and its relation to Northern Hemisphere temperature

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Chinese Science Bulletin 2003年第14期48卷 1480-1482页

作者： duan keqin YAO Tandong NationalLaboratoryofWesternChina'sEnvironmentalSystems LanzhouUniversity.Lanzhou730000.China

A 149.8-m-long ice core was drilled at theaccumulation area of Dasuopu glacier (28?3′N, 85?3′E, 7100 m a.s.l.) in the central Himalayas in 1997. The ice core was analyzed continuously for stable isotopes (d 18O), cations (Na+, K+, Mg2+, Ca2+) and anions (Cl-, 24SO,-3NO-) throughout the core. Cycles indicated by d 18O, cations and anions were identified and counted as seasonal fluctuations as annual increment from maximum to maximum values.Reconstructed 300-year annual net accumulation from thecore reveals a major precipitation trend for the central Himalayas with an average precipitation 750 mm per year. The trend, separated from the time series, shows a strongcorrelation to global temperature. Generally, as northernglobal temperature increases 0.1℃, the accumulationdecreases about 80mm and vise versa. This may suggests that monsoon precipitation in Himalayas have decreasedcontinuously in past decade as a response to global warming.

关键词：季风降水量喜马拉雅山脉北半球温度全球变暧

Response of monsoon vari-ability in Himalayas to global warming

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Chinese Science Bulletin 2002年第21期47卷 1842-1845页

作者： duan keqin YAO Tandong PU Jianchen SUN Weizhen Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of SciencesLanzhou 730000China

Reconstructed annual net accumulation from the Dasuopu ice core recovered in Himalayas, with a good correlation to Indian monsoon, reflects a major precipitation trend in central Himalayas. The Dasuopu accumulation (DSP An) also shows a strong correlation to the Northern Hemispheric temperature. Generally, as the Northern Hemispheric temperature increases by 0.1 K, the accumulation decreases by about 90 mm and vise versa. Under the condition of global warming, especially since 1920, the Northern Hemispheric mean temperature has increased by about 0.5 K, whereas accumulation in Dasuopu ice core has decreased by about 450 mm. According to the relationship between accumulation and temperature, a scenario prediction of monsoon rainfall in central Himalayas is made.

关键词： Dasuopu ice core accumulation global warming.

Numerical simulation of Urumqi Glacier No.1 in the eastern Tianshan,central Asia from 2005 to 2070

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Chinese Science Bulletin 2012年第34期57卷 4505-4509页

作者： duan keqin YAO TanDong WANG NingLian LIU HuanCai State Key Laboratory of Cryosphere Chinese Academy of SciencesLanzhou 730000China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100085China

Due to climate changes, most of the alpine glaciers have retreated dramatically during the past decades. Thus it is significant to predict the alpine glacier variability in the future for a better understanding of the impact of climate changes on water resource. In this paper, we perform the numerical simulation on Urumqi Glacier No.1 in the eastern Tianshan, central Asia (hereafter Glacier No.1 for short) by considering both the mass balance and ice flow. Given the shape of the Glacier No.1, the velocity of the glacier is obtained by solving a two-dimensional nonlinear Stokes equation and simulated result is in agreement with the observation. In order to predict the variability of Glacier No.1 in the next decades, a climatic scenario is constructed with a temperature rise rate as 0.17°C/10 a and precipitation as constant during the period of 2005-2070. The simulation shows that, the glacier terminus will retreat slowly and the glacier will thin dramatically before 2040, while after year 2040, the glacier terminus retreat will accelerate. This study confirms the increasing retreat rate of alpine glaciers under global warming.

关键词： 1号冰川数值模拟乌鲁木齐中亚地区东天山 Stokes方程气候变化影响预测

Ammonium record over the last 96 years from the Muztagata glacier in Central Asia

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Chinese Science Bulletin 2008年第8期53卷 1255-1261页

作者： ZHAO HuaBiao YAO TanDong XU BaiQing LI Zhen duan keqin State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China

As a major alkaline gas in the atmosphere, ammonia (NH3) plays an important role in atmospheric chemistry. However, there is little knowledge about NH3 variations in the Central Asia. Here we ana- lyzed the ammonium (NH+4) history recorded in an ice core from the East Pamir in Central Asia, which was drilled on the Mt. Muztagata at the elevation of 7010 m a.s.l. in 2003. The core was carefully dated and NH4+ concentration history during 1907―2002 was reconstructed. The result shows that NH4+ con- centration remained approximately constant until the 1930s after a sudden decrease at the very begin- ning of the 20th century, followed by a minimum in 1940 before increasing steadily to the peak at the end of 1990s. It is found that the annual mean NH4+ concentration was strongly associated with the Northern Hemisphere temperature, suggesting the impact of temperature on NH3 emissions in the Central Asia. Moreover, an increase of NH+4 concentration after 1940 also reflects the enhancement of NH3 emissions from anthropogenic sources such as fertilizer applications and livestock wastes in the 20th century.

关键词：冰块核心铵含量氨水散发冰川

气候变化背景下秦岭南北强降雪与小雪时空变化特征

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地理科学 2024年第5期44卷 890-900页

作者：李双双何锦屏段克勤延军平陕西师范大学地理科学与旅游学院陕西西安710119

不同等级降雪变化可反映气候变暖对关键气候变量趋势和极端性的综合影响。基于1970—2018年逐日气象观测数据,辅以湿球温度动态阈值法、趋势分析等气候诊断方法,论文对秦岭南北11月—次年3月强降雪和小雪时空变化特征进行分析,探究3个分... 详细信息

不同等级降雪变化可反映气候变暖对关键气候变量趋势和极端性的综合影响。基于1970—2018年逐日气象观测数据,辅以湿球温度动态阈值法、趋势分析等气候诊断方法,论文对秦岭南北11月—次年3月强降雪和小雪时空变化特征进行分析,探究3个分区(关中平原、秦岭南坡和汉江谷地)不同等级降雪与气温的响应关系。结果表明:①1970—2018年,秦岭南北11月—次年3月无降水日数增多,固态降水(降雪或雨夹雪)日数明显减少。1998年后,降雪日数比重由前期8.5%下降为5.2%。②秦岭南北小雪降雪量、降雪日数变化显著下降,降雪强度显著上升;强降雪3个指标变化趋势均不显著,说明区域降雪变化以小雪减少为主。③在气温响应关系上,秦岭南北3个子区小雪降雪量、降雪天数与气温显著负相关;关中平原、汉江谷地气温与强降雪量、天数显著负相关,秦岭南坡气温变化与强降雪3个指标相关性较弱。说明河谷平原区是强降雪对气温响应的敏感区。本文研究结论可为理解中国南北过渡带冬季气候响应规律提供理论基础。

关键词：气候变化强降雪雨雪判别方法秦岭南北

Seasonal variations of dust record in the Muztagata ice cores

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Chinese Science Bulletin 2008年第16期53卷 2506-2512页

作者： WU GuangJian YAO TanDong XU BaiQing TIAN LiDe LI Zhen duan keqin Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of Cryospheric Science Chinese Academy of Sciences Lanzhou 730000 China

Based on the oxygen isotope ratio and microparticle record in ice cores recovered at Mt. Muztagata, Eastern Pamirs, the seasonal variations of atmospheric dust have been reconstructed for the past four decades. High dust concentrations and coarser particle grains have the similar trend with oxygen iso- tope value. Our statistical results indicate that 50%―60% high dust concentration samples occur dur- ing the season with high oxygen isotope values (summer), while low dust storm frequency during spring and winter. Back-trajectory analysis shows that the air mass hitting Muztagata predominately came from West Asia (such as Iran-Afghanistan Plateau) and Central Asia, which are the main dust source area for Muztagata. Dust storms in those source areas most frequently occur during summer (from May to August), while frequent dust storm events in northern China mainly occur during spring (March to May). Regions in the path of Asian dust transport, such as in Japan, the North Pacific, and Greenland, also show high dust concentrations during spring (from March to May). Our results indicate that dust storms have different seasonality in different regions within Asia.

关键词：灰尘季节变化冰层氧同位素

Water isotope variations in the snow pack and summer precipitation at July 1 Glacier, Qilian Mountains in northwest China

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Chinese Science Bulletin 2007年第21期52卷 2963-2972页

作者： ZHOU ShiQiao NAKAWO Masayoshi SAKAI Akiko MATSUDA Yoshihiro duan keqin PU JianChen Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Institute of Plateau Meteorology China Meteorological Administration Chengdu 610071 China Research Institute for Humanity and Nature Kyoto 606-8502 Japan Graduate School of Environmental Studies Nagoya University Nagoya 464-8601 Japan Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

This paper presents the stable isotope data of the snow pack and summer precipitation collected at the July 1 Glacier, Qilian Mountains in northwest China and analyses their relationships with meteorologi- cal factors. On an event scale, there is no temperature effect on the δ 18O values in the summer pre- cipitation, whereas the amount effect is shown to be clear. By tracing the moisture transport history and comparing the precipitation with its isotopic composition, it is shown that this amount effect not only reflects the change in moisture trajectory, which is related to the monsoon activities, but is also associated with the cooling degree of vapor in the cloud, the evaporation of falling raindrops and the isotopic exchange between the falling drops and the atmospheric vapor. As very little precipitation occurs in winter, the snow pack profile mainly represents the precipitation in the other three seasons. There are low precipitation δ 18O ratios in summer and high ratios in spring and autumn. The Meteoric Water Line (MLW) for the summer precipitation is δ D = 7.6 δ 18O + 13.3, which is similar to that at Delingha, located in the south rim of the Qilian Mountains. The MWL for the snow pack is δ D = 10.4 δ 18O + 41.4, showing a large slope and intercept. The deuterium excess (d) of the snow pack is positively correlated with δ 18O, indicating that both d and δ 18O decrease from spring to summer and increase from early autumn to early spring. This then results in the high slope and intercept of the MWL. Sea- sonal fluctuations of d in the snow pack indicate the change of moisture source and trajectory. During spring and autumn, the moisture originates from continental recycling or rapid evaporation over rela- tively warm water bodies like Black, Caspian and Aral Seas when the dry westerly air masses pass over them, hence very high d values in precipitation are formed. During summer, the monsoon is responsi- ble for the low d values. This indicates that the monsoon can reach the western part of the Qilian Mount

关键词：青藏高原祁连山冰川降水粒雪

日本国立公园发展历程比较研究及其启示——以富士箱根伊豆国立公园和知床国立公园为例

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文化创新比较研究 2024年第5期8卷 102-108页

作者：朱恩卿段克勤北京林业大学北京100083

日本作为亚洲最早建立国家公园的国家,其国家公园的管理经验与发展模式可为其他国家尤其是正在建设国家公园的国家提供借鉴。富士箱根伊豆国立公园和知床国立公园是日本知名的国立公园,该文从两者的发展历程及其表现可以得出二者的发展... 详细信息

日本作为亚洲最早建立国家公园的国家,其国家公园的管理经验与发展模式可为其他国家尤其是正在建设国家公园的国家提供借鉴。富士箱根伊豆国立公园和知床国立公园是日本知名的国立公园,该文从两者的发展历程及其表现可以得出二者的发展模式不同。在二者差异较大的观光业发展基础上,可以将研究对象扩大为不局限于观光业的与外界的经济互动行为。文章通过综合运用比较分析、案例分析等方法,分层次从两个国立公园与公园外界(个人、团体、政府)的相异经济互动模式比较中,汲取可利用经验,以期为中国国家公园尚未完全定型的与公园外界的经济互动模式提供借鉴。

关键词：富士箱根伊豆国立公园知床国立公园日本国立公园发展历程互动模式比较研究中国国家公园

1990—2020年帕米尔高原无表碛覆盖冰川变化态势研究——基于Google Earth Engine平台

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冰川冻土 2024年第3期46卷 742-753页

作者：陈逸青段克勤石培宏李朝纲陕西师范大学地理科学与旅游学院陕西西安710119

帕米尔高原是亚洲高山区最大的冰川作用中心,其冰川融水在区域水资源与水循环中发挥关键作用。然而,近年来对帕米尔高原冰川变化的认识仍存在争议,一方面认为喀喇昆仑-帕米尔高原冰川存在异常前进现象,另一方面认为帕米尔冰川正在加剧... 详细信息

帕米尔高原是亚洲高山区最大的冰川作用中心,其冰川融水在区域水资源与水循环中发挥关键作用。然而,近年来对帕米尔高原冰川变化的认识仍存在争议,一方面认为喀喇昆仑-帕米尔高原冰川存在异常前进现象,另一方面认为帕米尔冰川正在加剧退缩。究其原因,一是研究时空范围不重合,二是研究中对冰川的定义有所不同。为明晰帕米尔高原无表碛覆盖冰川近30年来的时空变化情况,本研究基于Google Earth Engine(GEE)平台,利用Landsat 5 TM和Landsat 8 OLI遥感影像数据,消除掉云层遮蔽、季节性积雪和冰川表碛覆盖对无表碛覆盖冰川面积的影响,获取了帕米尔高原1990—2020年期间无表碛覆盖冰川时空变化特征。结果显示,在过去30年帕米尔高原无表碛覆盖冰川面积以116.42 km^(2)·a^(-1)的速率由(12 108.98±250.38) km^(2)缩减到(8 616.44±7.72) km^(2)。在空间上,帕米尔高原西部无表碛覆盖冰川面积总体上呈退缩趋势,而帕米尔东部无表碛覆盖冰川面积则相对稳定。特别是在2000—2010年期间,帕米尔东部无表碛覆盖冰川面积存在异常增加现象,但自2010年,冰川面积退缩加速,冰川末端前进现象已不存在。结合气候及冰川高程变化分析,冰川跃动引起的冰川厚度减薄、冰川末端前进,是1990—2010年间帕米尔高原冰川异常前进的主要原因。

关键词： Google Earth Engine 帕米尔高原无表碛覆盖冰川冰川异常