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Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： Jiacheng CHEN Jie CHEN Xunchang John ZHANG Peiyi PENG State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan UniversityWuhan 430072China USDA-ARS Oklahoma and Central Plains Agricultural Research Center El Reno OK 73036USA Southwest Research Institute for Hydraulic and Water Transport Engineering Chongqing Jiaotong UniversityChongqing 400016China

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***,accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in *** this study,a data fusion method based on Convolutional Neural Networks(CNN)is used to fuse the hydrogen isotopic composition(δ^(2)H_(p))of observations and isotope-equipped general circulation model(iGCM)simulations.A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50-60 km is established for East China for the 1969-2017 *** to building the isoscape,the performance of three data fusion methods(DFMs)and two bias correction methods(BCMs)is *** results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a *** fusion methods based on back propagation and long short-term memory neural network perform similarly,while slightly outperforming the bias correction ***,the CNN method is used to generate the hydrogen isoscape,and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this *** generated isoscape shows similar spatial and temporal distribution characteristics to *** general,the distribution pattern of δ^(2)H_(p) is consistent with the temperature effect in northern China,and consistent with the precipitation amount effect in southern *** trend of the δ^(2)H_(p) time series is consistent with that of observed precipitation and ***,the generated isoscape effectively reproduces the observations,and has the characteristics of time continuity and relative spatial regularity,which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope general circulation model Data fusion Dataset

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SEASONAL CHANGES OF SOIL MOISTURE INDUCED BY INCREASED CO2 AS SIMULATED BY THE ATMOSPHERIC general circulation AND MIXED LAYER OCEAN model

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Acta meteorologica Sinica 1992年第2期6卷 170-178页

作者：赵宗慈 Chinese Academy of Meteorological Sciences Beijing 100081

The atmospheric general circulation model coupled to the mixed layer ocean model has been used to simulate the changes of the global soil *** the simulated results with observations,it is shown that the model is ca- pable of doing sensitive experiments about the carbon dioxide change. The 2×CO_2/1×CO_2 comparison shows that there are the obvious changes of the soil moisture in the global for four *** are the wet soil moisture in the lower latitudes of both hemispheres and dry soil moisture in the mid- dle latitudes of both hemispheres for four *** dry soil moisture in summer and wet in other seasons are found in the northern higher latitudes. The analyses of the physical feedbacks responsible for the CO_2-induced changes of soil moisture show that the bud- gets of the surface water and heat are the important factors.

关键词： soil moisture general circulation model seasonal changes

Implementation of Turbulent Mixing over a Stratocumulus-Topped Boundary Layer and Its Impact in a GCM

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Advances in Atmospheric Sciences 2009年第5期26卷 995-1004页

作者： Sun-Hee SHIN Kyung-Ja HA Division of Earth Environmental System Pusan National University

The effect of a vertical diffusion scheme over a stratocumulus topped boundary layer （STBL） was investigated using the YONU AGCM （Yonsei University Atmospheric general circulation model）. To consider the impact of clouds on the turbulence production, the turbulence mixing term, driven by radiative cooling at the cloud top, is implemented as an extended non-local diffusion scheme. In the model with this new scheme, the STBL parameterization significantly influences the lower atmosphere over the tropical and subtropical regions. Consideration of the turbulent mixing within the cloud layer leads to continuous stratocumulus formation. The cloud-top radiative cooling tends to favor more rapid entrainment and produces top-down turbulent mixing. This cooling develops a mixed layer without initiation of deep convection by surface fluxes. Variations in thermodynamical and dynamical features are produced by planetary boundary layer （PBL） cloud development. The simulated stratocumulus induces more mixing of heat and moisture due to the cloud forcing. Over STBL regions, the lower boundary layer becomes warmer and drier. It also weakens vertical motion and zonal trade winds in the eastern Pacific, which indicates that stratocumulus cloud cover plays a role in weakening the Walker circulation; that is, cloud cover damps the tropical circulation.

关键词： stratocumulus topped boundary layer non-local diffusion scheme tropical circulation general circulation model

A review and comparison of surface incident shortwave radiation from multiple data sources: satellite retrievals, reanalysis data and GCM simulations

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International Journal of Digital Earth 2023年第1期16卷 1332-1357页

作者： Shuyue Yang Xiaotong Zhang Shikang Guan Wenbo Zhao Yanjun Duan Yunjun Yao Kun Jia Bo Jiang Faculty of Geographical Science State Key Laboratory of Remote Sensing ScienceBejjing Normal UniversityBejjingPeople's Republic of China

Surface incident shortwave radiation(Rs)can promote the circulation of substance and energy,and the accuracy of its estimation is of great significance for climate *** Rs can be acquired from satellite retrievals,reanalysis predictions and general circulation model(GCM)*** Rs estimates have been evaluated and compared in previous studies,most of them focus on evaluating the Rs estimates over specific regions using ground measurements from limited ***,it is essential to comprehensively validate Rs estimates from multiple data *** this study,ground measurements of 690 stations from BSRN,GEBA,CMA,GC-NET and buoys were employed to validate the Rs estimates from seven representative products(GLASS,GEWEX-SRB,CERES-EBAF,ERA5,MERRA2,CFSR and CMIP6).The validation results indicated that the selected products overestimated Rs globally,with biases ranged from 0.48 to 21.27 W/m^(2).The satellite retrievals showed relatively better accuracy among seven datasets compared to ground measurements at the selected ***,the selected seven products were all in poor accuracy at high-latitude regions with RMSEs greater than 50 W/m^(2).The long-term variation trends were also analyzed in this study.

关键词： Downward shortwave radiation satellite reanalysis general circulation model

Some features of effective radius and variance of dust particles in numerical simulations of the dust climate on Mars

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Earth and Planetary Physics 2021年第1期5卷 11-18页

作者： Chi-Fong Wong Kim-Chiu Chow Kwing LChan Jing Xiao Yemeng Wang Space Science Institute/State Key Laboratory of Lunar and Planetary Science Macao University of Science and TechnologyTaipaMacaoChina

Airborne dust is an important constituent in the Martian atmosphere because of its radiative interaction with the atmospheric *** size is one crucial factor in determining this *** reality dust sizes are varied;however,in numerical modeling of dust processes,dust size has usually been described by choice of a particular size distribution function,or by use of fixed values of effective radius(ER)and effective variance(EV).In this work,we present analytical expressions that have been derived to specify ER and EV for Nbin dust schemes,based on a model-calculated dust mixing *** simulations based on this approach thus would consider the effects of variable ER on the atmospheric radiation and their *** have revealed some interesting features of the dust distribution parameters,such as seasonal and spatial variation of ER and EV,which are generally consistent with some previous observational and modeling *** with the usual approach of using a fixed ER,simulation results from the present approach suggest that the variability of ER can have significant effects on the simulated thermal field of the Martian atmosphere.

关键词： Mars dust effective radius effective variance general circulation model

Understanding and building upon pioneering work of Nobel Prize in Physics 2021 laureates Syukuro Manabe and Klaus Hasselmann:From greenhouse effect to Earth system science and beyond

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Science China Earth Sciences 2022年第4期65卷 589-600页

作者： Tianjun ZHOU Wenxia ZHANG Deliang CHEN Xuebin ZHANG Chao LI Meng ZUO Xiaolong CHEN State Key Laboratory of Numerical modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Department of Earth Sciences University of GothenburgGothenburg 40530Sweden Environment and Climate Change Canada Toronto M3H 5T4Canada Max Planck Institute for Meteorology Hamburg 20146Germany

The Nobel Prize in Physics 2021 was awarded jointly to Syukuro Manabe,Klaus Hasselmann,and Giorgio Parisi for their groundbreaking contributions to our understanding of complex *** is the first time that climate scientists were awarded the Nobel Physics ***,we present the evolution of climate science in the past~200 years and highlight the landmarks of the developments in advancing our understanding of climate change,placing the pioneering contributions of Manabe and Hasselmann into a historical *** backbone of modern climate science is further discussed in the context of the development of the discipline from the discovery of the greenhouse effect to the formation of Earth system *** on the future development of climate science are also`presented.

关键词： Greenhouse gases Climate change general circulation model Detection and attribution Climate science Earth system science

Effects of Climatic Change on Evapotranspiration in Zhalong Wetland,Northeast China

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Chinese Geographical Science 2006年第3期16卷 265-269页

作者： WANG Hao XU Shiguo SUN Leshi Institute of Water and Environmental Research Department of Civil Engineering Dalian University of Technology Dalian 116023 China Meteorological Bureau of Qiqihar Qiqihar 161000 China

Evapotranspiration （ET） process of plants is controlled by several factors. Besides the physiological factors of plants, height, density, LAI （leaf area index）, etc., the change of meteorological factors, such as radiation, temperature, wind and precipitation, can influence ET process evidently, thus remodeling the spatial and temporal distribution of ET. In order to illuminate the effects of meteorological factors on wetland ET, the ET of Zhalong Wetland was calculated from 1961 to 2000, the statistical relationships （models） between ET and maximum temperature （Tmax）, minimum temperature （Tmin）, precipitation （P） and wind speed at 2m height （U2） were established, and the sensitivity analysis of the variables in the model was performed. The results show that Tmax and Tmin are two dominating factors that influence ET markedly, and the difference of rising rate between Tmax and Tmin determines the change trend of ET. With the climatic scenarios of four general circulation models （GCMs）, the ET from 2001 to 2060 was predicted by the statistical model. Compared to the period of 1961-2000, the water consumption by ET will increase greatly in the future. According to the scenarios, the rise of Tmax （about 1.5℃ to 3.3℃） and Tmin （about 1.7℃ to 3.5℃） will cause an additional water consumotion of 14.0%- 17.8% for reed swami）. The ecological water demand in Zhalong Wetland will become more severe.

关键词： climate change evapotranspiration general circulation model Zhalong Wetland

Seasonal　and　Extraseasonal　Predictions　of　Summer　Monsoon　Precipitation　by　Gcms

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Advances in Atmospheric Sciences 1997年第2期14卷 40-53页

作者：曾庆存袁重光李旭张荣华杨芳林张邦林卢佩生毕训强王会军 Institute of Atmopheric Physics Chinese Academy of Sciences

A semi-operational real time short-term climate prediction system has been developed in the Center of Climate and Environment Prediction Research (CCEPRE), Institute of Atmospheric Physics/Chinese Academy of Sciences. The system consists of the following components: the AGCM and OGCM and their coupling, initial conditions and initialization, practical schemes of anomaly prediction, ensemble prediction and its standard deviation, correction of GCM output, and verification of prediction. The experiences of semi-operational real-time prediction by using this system for six years (1989-1994) and of hindcasting for 1980-1989 are reported. It is shown that in most cases large positive and negative anomalies of summer precipitation resulting in disastrous climate events such as severe flood or drought over East Asia can be well predicted for two seasons in advance, although the quantitatively statistical skill scores are only satisfactory due to the difficulty in correctly predicting the signs of small anomalies. Some methods for removing the systematic errors and introducing corrections to the GCM output are suggested. The sensitivity of prediction to the initial conditions and the problem of ensemble prediction are also discussed in the paper.

关键词： Seasonal and Extraseasonal Predictions general circulation model

Direct Climatic Effect of Dust Aerosol in the NCAR Community Atmosphere model Version 3 (CAM3)

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Advances in Atmospheric Sciences 2010年第2期27卷 230-242页

作者：乐旭王会军廖宏范可 Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Center (NZC) Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences

Direct climate responses to dust shortwave and longwave radiative forcing （RF） are studied using the NCAR Community Atmosphere model Version 3 （CAM3）. The simulated RF at the top of the atmosphere （TOA） is-0.45 W m-2 in the solar spectrum and ＋0.09 W m-2 in the thermal spectrum on a global average. The magnitude of surface RF is larger than the TOA forcing, with global mean shortwave forcing of-1.76 W m-2 and longwave forcing of ＋0.31 W m-2 . As a result, dust aerosol causes the absorption of 1.1 W m-2 in the atmosphere. The RF of dust aerosol is predicted to lead to a surface cooling of 0.5 K over the Sahara Desert and Arabian Peninsula. In the meantime, the upper troposphere is predicted to become warmer because of the absorption by dust. These changes in temperature lead to a more stable atmosphere, which results in increases in surface humidity. The upward sensible and latent heat fluxes at the surface are reduced, largely balancing the surface energy loss caused by the backscattering and absorption of dust aerosol. Precipitation is predicted to decrease moderately on a global scale.

关键词： dust aerosol radiative forcing direct radiative effect general circulation model