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The Influence of Large-Scale Circulation on the Summer hydrological cycle in the Haihe River Basin of China

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Acta meteorologica Sinica 2011年第4期25卷 517-526页

作者： OU Tinghai LIU Yanxiang CHEN Deliang David RAYNER ZHANG Qiang GAO Ge XIANG Weiguo School of Geology Beijing Normal University Beijing 100875 China Department of Earth Sciences University of Gothenburg GSteborg 40530 Sweden National Climate Center China Meteorological Administration Beijing 100081 China College of Atmospheric Sciences Chengdu University of Information Science ~ Technology Chengdu 610225 China

In this study, we focus on changes in three important components of the hydrological-cycle in the Haihe River basin （HRB） during 1957-2005： precipitation （Prep）, actual evaportranspiration （ETa）, and pan evaporation （PE）-a measure of potential evaporation. The changes in these components have been evaluated in relation to changes in the East Asian summer monsoon. Summer Prep for the whole basin has decreased significantly during 1957-2005. Recent weakening of the convergence of the integrated water vapor flux, in combination with a change from cyclonic-like large-scale circulation conditions to anti-cyclonic-like conditions, led to the decrease in the summer Prep in the HRB. ETa is positively correlated with Prep on the interannual timescale. On longer timescales, however, ETa is less dependent on Prep or the large-scale circulation. We found negative trends in ETa when the ERA40 reanalysis data were used, but positive trends in ETa when the NCEP/NCAR reanalysis data were used. PE declined during the period 1957-2001. The declining of PE could be explained by a combination of declining solar radiation and declining surface wind. However, the declining solar radiation may itself be related to the weakening winds, due to weaker dispersion of pollution. If so, the downward trend of PE may be mainly caused by weakening winds.

关键词： hydrological cycle runoff Lamb-Jenkinson classification circulation Haihe River basin (HRB)

Simulations of hydrological cycle Changes Between the LGM and the Present Day over China

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Acta meteorologica Sinica 2010年第5期24卷 641-656页

作者：刘煜李维凳何金海陈隆勋 Chinese Academy of Meteorological Sciences Nanjing University of Information Science & Technology

Based on the International Satellite Cloud Climatology Project（ISCCP）data in 1983-2006,it is found that there is a high value center of high cloud amount over the Tibetan Plateau（TP）,while there is a high value center of middle cloud amount over the Sichuan Basin extending to the coastal area of southeastern China along the same latitude,and a low one over the *** present day（PD）and Last Glacial Maximum（LGM）climates are simulated by using the NCAR Community Climate Model（CCM3）nested with a regional mesoscale model（MM5）.Comparing the clouds simulated by MM5 with the ISCCP data,it is found that the main patterns of high and middle clouds over China can be reproduced by MM5,which implies that the climate characteristics of clouds might he dominated by relative ***,the vertical distributions of water vapor and temperature are also well simulated by ***,the hydrological cycle changes between the LGM and PD simulations are *** results show that during the LGM,the tropospheric temperature decreases in summer with a high value reduction center in the upper and middle troposphere; in winter,a high value reduction center of temperature appears in the middle troposphere over southern China,while the temperature in the upper and middle troposphere increases over northern *** obviously exists a positive correlation between the water vapor content and temperature *** water vapor content mostly decreases with the maximum drop in the near-ground surface layer,but it increases in the upper and middle troposphere over northern China in *** of water vapor content gradually weaken with the altitude increasing,reaching the minimum in the upper *** relative humidity can either increase or decrease with the maximum change greater than 15%.It is not conservative on the regional scale,and its change is consistent with the changes of middle and low *** the LGM,the high cloud reduces nationwide except over

关键词： Last Glacial Maximum(LGM) hydrological cycle China

Global and Regional Impacts of Vegetation on the hydrological cycle and Energy Budget as Represented by the Community Atmosphere Model (CAM3)

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Atmospheric and Oceanic Science Letters 2009年第2期2卷 85-90页

作者： XU Zhongfeng ZENG Gang FU Congbin RCE-TEA Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science ＆ Technology Nanjing 210044 China School of Atmospheric Sciences Nanjing University Nanjing 210093 China

The effects of vegetation and its seasonal variation on energy and the hydrological cycle were examined using a state-of-the-art Community Atmosphere Model （CAM3）. Three 15-year numerical experiments were completed： the first with realistic vegetation characteristics varying monthly （VEG run）, the second without vegetation over land （NOVEG run）, and the third with the vegetation characteristics held at their annual mean values （VEGMEAN run）. In these models, the hydrological cycle and land surface energy budget were widely affected by vegetation. Globaland annual-mean evapotranspiration significantly increased compared with the NOVEG by 11.8% in the VEG run run, while runoff decreased by 13.2% when the realistic vegetation is incorporated. Vegetation plays different roles in different regions. In tropical Asia, vegetation-induced cooling of the land surface plays a crucial role in decreasing tropical precipitation. In middle latitudes and the Amazon region, however, the vegetation-induced increase of evapotranspiration plays a more important role in increasing precipitation. The seasonal variation of vegetation also shows clear influences on the hydrological cycle and energy budget. In the boreal mid-high latitudes where vegetation shows a strong seasonal cycle, evapotranspiration and precipitation are higher in the summer in the VEG run than in the VEGMEAN run.

关键词： vegetation seasonal variation hydrological cycle energy budget regional climate

Detection and Attribution of Observed Changes in the hydrological cycle under Global Warming

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Advances in Climate Change Research 2011年第1期2卷 31-37页

作者： Chunzhen Liu Jun Xia Water Resources Information Center Ministry of Water Resources Beijing 100053 China Key Lab of Water cycle ＆ Related Land Surface Processes Institute of Geographical Sciences National Resources Research Chinese Academy of Sciences Beijing 100101 China

The progress and advances of the detection and attribution of changes in the hydrological cycle in the IPCC Assessment Reports of WGI and WGII from 1990 to 2007 are reviewed. Accomplishment and endorsed by the joint Expert Meeting on Detection and Attribution in 2009, the Good Practice Guidance Paper （GPGP） for IPCC Lead Authors with its main content and characteristics are briefly introduced. Based on the review and the purpose of the GPGP, some characteristics on the detection and attribution of global warming and of changes in the hydrological cycle are presented.

关键词： IPCC Assessment Report climate change hydrological cycle detection and attribution

Changes of the hydrological cycle in two typical Chinese monsoonal temperate glacier basins,： A response to global warming？

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Journal of Geographical Sciences 2012年第5期22卷 771-780页

作者： PANG Hongxi LI Zongxing Wilfred H. THEAKSTONE Key Laboratory of Coast and Island Development of Ministry of Education School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China Gansu Hydrology and Water Resources Engineering Research Center/Alashan Desert Eco-hydrology Ex-perimental Research Station Cold and Arid Regions Environmental and Engineering Research InstituteCAS Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Environment and Development University of Manchester Manchester M13 9PL England UK

Studying the response to warming of hydrological systems in Chin＇s temperate glacier region is essential in order to provide information required for sustainable develop- ment. The results indicated the warming climate has had an impact on the hydrological cycle. As the glacier area subject to melting has increased and the ablation seasor has become longer, the contribution of meltwater to annual river discharge has increased. The earlier onset of ablation at higher elevation glaciers has resulted in the period of minimum discharge occurring earlier in the year. Seasonal runoff variations are dominated by snow and glacier melt, and an increase of meltwater has resulted in changes of the annual water cycle in the Lijiang Basin and Hailuogou Basin. The increase amplitude of runoff in the downstream re- gion of the glacial area is much stronger than that of precipitation, resulting from the promi- nent increase of meltwater from glacier region in two basins. Continued observations in the glacierized basins should be undertaken in order to monitor changes, to reveal the relation- ships between climate, glaciers, hydrology and water supplies, and to assist in maintaining sustainable regional development.

关键词： global warming hydrological cycle temperate glacier basins

Quantitative estimation of global mean precipitation throughout the Phanerozoic era

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Science China Earth Sciences 2024年第5期67卷 1616-1624页

作者： Xiujuan BAO Yongyun HU Laboratory for Climate and Ocean-Atmospheric Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871China

Quantitatively estimating the global mean precipitation(GMP)throughout Earth's history is crucial for enhancing our understanding of long-term climate evolution and the hydrological ***,currently there is no established methodology for estimating global mean ***,we present the first study that estimates GMP in the Phanerozoic *** relationship between GMP and global mean surface temperature(GMST)is investigated by analyzing data from 23 models in the Coupled Model Intercomparison Project phase 6(CMIP6).The result reveals consistent and significant impact of temperature on precipitation,with a sensitivity range of 2–3%K^(-1).Additionally,we propose a method for accessing latitudinal variations in precipitation caused by land area distributions and paleo-Koppen climatic *** climatic belts are determined based on geological indicators such as coals,evaporites,and glacial *** GMP is thus quantitatively estimated by combining variations in GMST,land area distributions,and paleo-koppen climatic belts,spanning from 540 Ma to the present *** quantitative GMP curve demonstrates fluctuations in GMP about 500 mm yr^(-1),with values ranging from 948 to1442 mm yr-1over the Phanerozoic *** curve aligns closely with findings derived from numerical *** presented paleoprecipitation variations facilitate a more comprehensive understanding of the interconnected geological and paleoclimatic developments.

关键词： Paleoprecipitation Paleoclimate K?ppen climatic belts Global mean precipitation hydrological cycle

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Oceanic Origin of A Recent La Nin a-Like Trend in the Tropical Pacific

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Advances in Atmospheric Sciences 2011年第5期28卷 1109-1117页

作者：张丽萍吴立新于立三 Physical Oceanography Laboratory Ocean University of China Qingdao 266100 Department of Oceanography Woods Hole Oceanography Institute MA 02543 USA

Global ocean temperature has been rising since the late 1970s at a speed unprecedented during the past century of *** accelerated warming has profound impacts not only on the marine ecosystem and oceanic carbon uptake but also on the global water cycle and *** this rapid warming period,the tropical Pacific displays a pronounced La Nin a-like trend,characterized by an intensification of west-east SST gradient and of atmospheric zonal overturning circulation,namely the Walker *** La Nin a-like trend differs from the El Nin o-like trend in warm climate projected by most climate models,and cannot be explained by responses of the global water cycle to warm *** results of this study indicate that the intensification of the zonal SST gradient and the Walker circulation are associated with recent strengthening of the upper-ocean meridional overturning circulation.

关键词： tropical Pacific warming trend hydrological cycle subtropical tropical cell

Connection Between Atmospheric Latent Energy and Energy Fluxes Simulated by Nine CMIP5 Models

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Journal of Meteorological Research 2015年第3期29卷 412-431页

作者：韩博吕世华李瑞青奥银焕陈昊高艳红马迪 Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The atmospheric latent energy and incoming energy fluxes of the atmosphere are analyzed here based on the historical simulations of nine coupled models from the Coupled Model Intercomparison Project Phase 5 （CMIP5） and two reanalysis datasets. The globally averaged atmospheric latent energy is found to be highly correlated with several types of energy flux, particularly the surface latent heat flux, atmosphere absorbed solar radiation flux, and surface net radiation flux. On the basis of these connections, a hydrological cycle controlled feedback （HCCF） is hypothesized. Through this feedback, the atmosphere absorbed solar radiation is enhanced and causes intensification of the surface latent heat flux when the atmospheric latent energy is abnormally strong. The representativeness of the HCCF during different periods and over different latitudinal zones is also discussed. Although such a feedback cannot be confirmed by reanalysis, it proves to be a common mechanism for all the models studied.

关键词： atmospheric latent energy CMIP5 hydrological cycle climate feedback

Evaluation of the energy budget of thermokarst lake in permafrost regions of the Qinghai-Tibet Plateau

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Advances in Climate Change Research 2024年第4期15卷 636-646页

作者： Ze-Yong GAO Fu-Jun NIU Yi-Bo WANG Jing LUO Guo-An YIN Yun-Hu SHANG Zhan-Ju LIN Key Laboratory of Cryospheric Science and Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of ScienceLanzhou 730000China College of Earth and Environment Science Lanzhou UniversityLanzhou 73000China

Thermokarst lake formation accelerates permafrost degradation due to climate warming,thereby releasing significant amounts of carbon into the atmosphere,complicating hydrological cycles,and causing environmental ***,the energy transfer mechanism from the surface to the sediment of thermokarst lakes remains largely unexplored,thereby limiting our understanding of the magnitude and duration of biogeochemical processes and hydrological ***,herein,a typical thermokarst lake situated in the center of the Qinghai-Tibet Plateau(QTP)was selected for observation and energy budget *** results showed that the net radiation of the thermokarst lake surface was 95.1,156.9,and 32.3 W m^(-2) for the annual,ice-free,and ice-covered periods,respectively,and was approximately 76%of the net radiation consumed by latent heat *** in heat storage in the thermokarst lake initially increased from January to April,then decreased from April to December,with a maximum change of 48.1 W m^(-2) in *** annual average heat fuxes from lake water to sediments were 1.4 W m^(-2);higher heat fluxes occurred during the ice-free season at a range of 4.9-12.0 W m^(-2).The imbalance between heat absorption and release in the millennium scale caused the underlying permafrost of the thermokarst lake to completely *** present,the ground temperature beneath the lake bottom at a depth of 15 m has reached 2.0℃.The temperatures and vapor-pressure conditions of air and lake surfaces control the energy budget of the thermokarst *** findings indicate that changes in the hydrologic regime shifts and biogeochemical processes are more frequent under climate warming and permafrost degradation.

关键词： Qinghai-Tibet Plateau Thermokarst lake Energy budget Permafrost degradation hydrological cycle