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Regime Behavior in the Sea Surface Temperature-Cloud Radiative Forcing Relationships over the Pacific Cold Tongue Region

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Atmospheric and Oceanic Science Letters 2010年第5期3卷 271-276页

作者： WU Chun-Qiang zhou tian-jun De-Zheng SUN State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysieal Fluid Dynamics （LASG） Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China National Satellite Meteorological Center China Meteorological Administration Beijing 100081 China Cooperative Institute for Environmental Studies/University of Colorado ＆ NOAA/Earth System Research Laboratory Boulder Colorado USA

Previous analyses on the estimates of water vapor and cloud-related feedbacks in the tropics usually use observations over the Earth Radiation Budget Experiment （ERBE） period （1985-89）. To examine the sample dependence of previous estimates, the authors extend the analysis to two additional periods： 1990-94 and 1995-99. The results confirm our hypothesis, i.e., the values of the feedbacks depend on the period of data coverage. The differences in the feedbacks from cloud radiative forcings （CRFs） estimated from the three periods are particularly significant. Two possible causes for these differences are proposed. First, a regime behavior in the CRFs-Sea Surface Temperature Anomaly （SSTA） rela- tionship over the cold tongue region is revealed： when SSTA is below -0.5℃, the CRF anomalies are insensitive to the SSTA; when the SSTA is between -0.5℃ and 2.0℃, the CRF anomalies are positively correlated with the SSTA; however, when the SSTA exceeds 2.0℃, the CRF anomalies decrease with the SSTA. This regime behavior is due to the regime behavior of cirrostratus and deep convective clouds. Second, the CRFs-SSTA relationship is regulated by remote forcings. Warming of the far eastern equatorial Pacific would reduce the water vapor convergence over the central Pacific by weakening the trade wind over the southeastern Pacific, thereby reducing the feeding of moisture to the convective flow. The results suggest that CRFs-SSTA relationships during ENSO events are nonlinear and strongly depend on the magnitude and the spatial distribution of the SSTA.

关键词： cloud radiative feedback cloud-SST regime ENSO nonlinearity

Causes of the Intraseasonal SST Variability in the Tropical Indian Ocean

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Atmospheric and Oceanic Science Letters 2008年第1期1卷 18-23页

作者： Tim Li Francis Tam Xiouhua Fu zhou tian-jun ZHU Wei-jun IPRC and Department of Meteorology University of Hawaii at Manoa Honolulu Hawaii USA Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Joint Climate Institute of CMA ＆ NUIST Nanjing University of Information Science ＆ Technology Nanjing 210044 China

Satellite observations reveal a much stronger intraseasonal sea surface temperature （SST） variability in the southern Indian Ocean along 5-10°S in boreal winter than in boreal summer. The cause of this seasonal dependence is studied using a 2 1/2-layer ocean model forced by ERA-40 reanalysis products during 1987-2001. The simulated winter-summer asymmetry of the SST variability is consistent with the observed. A mixed-layer heat budget is analyzed. Mean surface westerlies along the ITCZ （5-10°S） in December-January-February （DJF） leads to an increased （decreased） evaporation in the westerly （easterly） phase of the intraseasonal oscillation （ISO）, during which convection is also enhanced （suppressed）. Thus the anomalous shortwave radiation, latent heat flux and entrainment effects are all in phase and produce strong SST signals. During june-July-August （JJA）, mean easterlies prevail south of the equator. Anomalies of the shortwave radiation tend to be out of phase to those of the latent heat flux and ocean entrainment. This mutual cancellation leads to a weak SST response in boreal summer. The resultant SST tendency is further diminished by a deeper mixed layer in JJA compared to that in DJF. The strong intraseasonal SST response in boreal winter may exert a delayed feedback to the subsequent opposite phase of ISO, implying a two-way air-sea interaction scenario on the intraseasonal timescale.

关键词： SST ISO shortwave radiation latent heatflux ocean entrainment

Improved simulation of the East Asian winter monsoon interannual variation by IAP/LASG AGCMs

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Atmospheric and Oceanic Science Letters 2016年第3期9卷 204-210页

作者： JIN Chen-Xi zhou tian-jun GUO Zhun WU Bo CHEN Xiao-Long State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences

The simulation of the East Asian winter monsoon （EAWM） has been a challenge for climate models. In this study, the performances of two versions of the AGCM developed at the lAP, versions 1 and 2 of the Grid-point Atmospheric Model of the IAP/LASG （GAMIL1 and GAMIL2）, are evaluated in the context of mean state and interannual variation. Significant improvements are shown for GAMIL2 in comparison to GAMIL1. The simulated interannual variability of the EAWM, measured by the regional average of 1000 hPa meridional wind over East Asia, has evidently improved; the correlation coefficient with reanalysis data changes from 0.37 in GAMIL1 to 0.71 in GAMIL2. The associated interannual precipitation anomalies are also improved, in terms of both spatial pattern and magnitude. Analysis demonstrates that the improvements result from the better simulation of the El Nino-related Philippine Sea anticyclone （PSAC） in GAMIL2. The improved moist processes, including the stratiform condensation and evaporation in GAMIL2, lead to a reasonable atmospheric heating associated with El Nitro in the tropical Pacific, which further drives the PSAC as a Rossby- wave response.

关键词： East Asian winter monsoon El Nino Grid-point Atmospheric Model of the IAP/LASG Philippine Seaanticyclone atmosphericheating

ENSO Signals in Tropospheric Temperature Simulated by an AGCM GAMIL

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Atmospheric and Oceanic Science Letters 2011年第3期4卷 186-190页

作者： YU Chao-Yue zhou tian-jun BIAN Jian-Chun State Key Laboratory of Numerical Modeling for Atmospheric＇ Sciences and Geophysical Fluid Dynamics （LASG） Institute of At- mospheric Physics （lAP） Chinese Academy of Scienees Beijing 100029 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Sciences Beijing 100029 China

Using reanalysis data as a benchmark, the authors evaluate the performance of an Atmospheric General Circulation Model （AGCM） named GAMIL （Grid-point Atmospheric Model of LASG/IAP）. GAMIL is used to simulate the tropospheric temperature anoma- lies associated with the El Nifio-Southern Oscillation （ENSO） in boreal winters for the period 1980-99. The results show that the symmetrical components of tem- perature anomalies simulated by GAMIL closely resem- ble those in the reanalysis data in spatial patterns, espe- cially in the Northern Hemisphere. The limitation of the model is that the simulated cold anomaly over South Asia is located to the east of the reanalysis. The observed tem- perature anomalies in the South Pacific and the high lati- tudes of the Southern Hemisphere are not evident in the simulation. The maximum value is 0.8 K smaller and the minimum value is -0.4 K smaller than the reanalysis. The difference between the simulation and the reanalysis is more evident in the regional features of the asymmetrical components of the temperature anomalies. Our results demonstrate that the previously discovered weak response of the GAMIL model to specified sea surface temperature forcing is dominated by the symmetric （asymmetric） component in the tropics （extra-tropics）.

关键词： ENSO middle troposphere temperatureanomaly GAMIL

Catalyst-free and Reprocessable Aromatic Polydithiourethanes

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Chinese Journal of Polymer Science 2024年第10期42卷 1435-1441,I0007页

作者： Bo Yang Hai-jun Feng tian-tian Ni Xiao-Rui zhou Tao Xie Ning Zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310058China Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China

The incorporation of dynamic covalent bonds into thermosets facilitates the reprocessing of polymer networks,thereby meeting the sustainable requirements for polymer ***,the mechanical properties of many materials often decline significantly upon reprocessing due to side reactions caused by harsh processing *** this work,we find that the aromatic dithiocarbamate bond can undergo dissociation under mild conditions without the need for a catalyst,enabling the efficient reprocessing of the corresponding *** a consequence,the mechanical properties of the polydithiourethane can be largely preserved after *** discovery of this dynamic chemistry is anticipated to broaden the potential for material design in dynamic covalent polymer networks.

关键词： Reprocessing Polydithiourethane Dynamic covalent bond

Influence characteristics of water penetration on fibre-reinforced polymer/rigid polyurethane foam interface of the composite cross-arm considering natural ageing

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High Voltage 2024年第1期9卷 81-93页

作者： jun Xie Zhe zhou Ziqian Liu Haonan tian Sigang Zhang Qing Xie Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina State Grid Gansu Electric Power Company LanzhouChina

Fibre-reinforced polymer(FRP)/rigid polyurethane foam(RPUF)interface is susceptible to moisture intrusion in addition to natural ageing during *** study investigated the influence of moisture intrusion on the FRP/RPUF interface under natural ageing using experiments and molecular dynamics(MD)*** absorption,shear strength,and leakage current tests were used to clarify the changes in the interface *** degradation mechanism of moisture intrusion at the interface under natural ageing was revealed by MD simulation and *** results show that the natural ageing of interfacial materials will slightly reduce the quality of the interface but will reduce the water resistance of the material and promote the process of water intrusion into the *** addition,water mainly invades the interface through *** water penetration,the interfacial bonding strength and insulation performance significantly *** and hydrolysis of interfacial materials are the main reasons for decreased interfacial *** can cause irreversible damage to the interface,increasing interface defects and water *** vicious cycle of material hydrolysis is the ultimate cause of interfacial *** polar molecules produced by this process and the water absorbed by the interface caused the degradation of the interface insulation performance.

关键词： interface polyurethane interfacial

Simulation of the Ecosystem Productivity Responses to Aerosol Diffuse Radiation Fertilization Effects over the Pan-Arctic during 2001–19

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Advances in Atmospheric Sciences 2024年第1期41卷 84-96页

作者： Zhiding ZHANG Xu YUE Hao zhou jun ZHU Yadong LEI Chenguang tian Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&Technology(NUIST)Nanjing 210044China Climate Change Research Center Institute of Atmospheric Physics(IAP)Chinese Academy of Sciences(CAS)Beijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Severe Weather&Key Laboratory of Atmospheric Chemistry of CMA Chinese Academy of Meteorological SciencesBeijing 100081China

The pan-Arctic is confronted with air pollution transported from lower *** have shown that aerosols help increase plant photosynthesis through the diffuse radiation fertilization effects(DRFEs).While such DRFEs have been explored at low to middle latitudes,the aerosol impacts on pan-Arctic ecosystems and the contributions by anthropogenic and natural emission sources remain less ***,we perform regional simulations at 0.2o×0.2ousing a well-validated vegetation model(Yale Interactive terrestrial Biosphere,YIBs)in combination with multi-source of observations to quantify the impacts of aerosol DRFEs on the net primary productivity(NPP)in the pan-Arctic during *** show that aerosol DRFEs increase pan-Arctic NPP by 2.19 Pg C(12.8%)yr^(-1)under clear-sky conditions,in which natural and anthropogenic sources contribute to 8.9% and 3.9%,*** all-sky conditions,such DRFEs are largely dampened by cloud to only 0.26 Pg C(1.24%)yr^(-1),with contributions of 0.65% by natural and 0.59% by anthropogenic *** aerosols cause a positive NPP trend of 0.022% yr^(-1)following the increased fire activities in the *** contrast,anthropogenic aerosols induce a negative trend of-0.01% yr^(-1)due to reduced emissions from the middle *** trends in aerosol DRFEs show a turning point in the year of 2007 with more positive NPP trends by natural aerosols but negative NPP trends by anthropogenic aerosols *** affected by modeling uncertainties,this study suggests a likely increasing impact of aerosols on terrestrial ecosystems in the pan-Arctic under global warming.

关键词： diffuse radiation fertilization effects anthropogenic aerosols natural aerosols pan-Arctic net primary productivity

The Extreme Summer Precipitation over East China during 1982-2007 Simulated by the LASG/IAP Regional Climate Model

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Atmospheric and Oceanic Science Letters 2012年第1期5卷 62-67页

作者： LIU Jing-Wei LI Bo zhou tian-jun ZENG Xian-Feng FENG Lei State Key Laboratory of Numerical modeling for Atmospheric Science and Geophysical Fluid Dynamics （LASG） Institute of Atmospheric Physics （lAP） Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The extreme summer precipitation over East China during 1982-2007 was simulated using the LASG/IAP regional climate model CREM(the Climate version of a Regional Eta-coordinate Model).The results show that the probability density functions(PDFs) of precipitation intensities are reasonably simulated,except that the PDFs of light and moderate rain are underestimated and that the PDFs of heavy rain are *** extreme precipitation amount(R95p) and the percent contribution of extreme precipitation to the total precipitation(R95pt) are also reasonably reproduced by the ***,the R95p and R95pt over most of East China are generally overestimated,while the R95p along the coastal area of South China(SC) is *** bias of R95pt is consistent with the bias of precipitation intensity on wet days(SDII).The interannual variation for R95p anomalies(PC1) is well simulated,but that of R95pt anomalies(PC2) is poorly *** skill of the model in simulating PC1(PC2) increases(decreases) from north to *** bias of water vapor transport associated with the 95th percentile of summer daily precipitation(WVTr95) explains well the bias of the simulated extreme precipitation.

关键词： regional climate simulation extreme precipi- tation East China CREM

East China Summer Rainfall during ENSO Decaying Years Simulated by a Regional Climate Model

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Atmospheric and Oceanic Science Letters 2011年第2期4卷 91-97页

作者： ZENG Xian-Feng LI Bo FENG Lei LIU Xiao-Juan zhou tian-jun State Key Laboratory of Numerical modeling for Atmospheric Science and Geophysical Fluid Dynamics （LASG） Institute of Atmospheric Physics Chinese Aeademy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

The performance of the Climate version of the Regional Eta-coordinate Model （CREM）, a regional climate model developed by State Key Laboratory of Numerical modeling for Atmospheric Science and Geophysical Fluid Dynamics/Institute of Atmospheric Physics （LASG/IAP）, in simulating rainfall anomalies during the ENSO decaying summers from 1982 to 2002 was evalu- ated. The added value of rainfall simulation relative to reanalysis data and the sources of model bias were studied. Results showed that the model simulated rainfall anomalies moderately well. The model did well at capturing the above-normal rainfall along the Yangtze River valley （YRV） during E1 Nifio decaying summers and the below and above-normal rainfall centers along the YRV and the Huaihe River valley （HRV）, respectively, during La Nifia decaying summers. These features were not evident in rainfall products derived from the reanalysis, indicating that rainfall simulation did add value. The main limitations of the model were that the simulated rainfall anomalies along the YRV were far stronger and weaker in magnitude than the observations during E1 Nifio decaying summers and La Nifia decaying summers, respectively. The stronger magnitude above-normal rainfall during E1 Nifio decaying summers was due to a stronger northward transport of water vapor in the lower troposphere, mostly from moisture advection. An artificial, above-normal rainfall center was seen in the region north to 35°N, which was associated with stronger northward water vapor transport. Both lower tropospheric circulation bias and a wetter model atmosphere contributed to the bias caused by water vapor transport. There was a stronger southward water vapor transport from the southern boundary of the model during La Nifia decaying summers; less remaining water vapor caused anomalously weaker rainfall in the model as compared to observations.

关键词： East China rainfall ENSO decaying summers regional climate model water vapor