Climate Services Elaboration for Cocoa Cultivation in Côte d’Ivoire: Contribution of CORDEX Climate Projections

This study assessed the contribution of climate projections to improving rainfall information for cocoa crops in the central and southern regions of Côte d’Ivoire. Particular attention was paid to fourteen localities in these two climatic zones. Simulation data were obtained from the CORDEX ensemble and observation data from CHIRPS. They cover the period 1991-2005 for the reference period and the future period from 2021 to 2050 for the RCP4.5 and RCP8.5 scenarios. In addition, the study was based on the water requirements necessary during the critical phase of the cocoa tree (the flowering phase) for a good yield from the cocoa production chain on the one hand, and on a selection of three climate indices CDD, CWD and r95PTOT to study their spatio-temporal changes over two future periods 2021-2035 (near future) and 2036-2050 (medium-term) on the other. These climatic indices influence cocoa cultivation and their use in studies of climatic impacts on agriculture is of prime importance. The analysis of their spatio-temporal changes in this work also contributes to providing climate services based on rainfall, to which cocoa crops are highly sensitive. Our results show that the CDD and CWD indices vary from one region to another depending on latitude. For the fourteen localities studied, the number of consecutive dry days (CDD) could increase between now and 2050, while the number of consecutive wet days (CWD) could decrease over the period 2021-2035 and then increase over the period 2036-2050. The localities of Tabou, Aboisso and San-Pedro record high numbers of CDD index and CWD index for both projection scenarios. In comparison with the RCP4.5 and RCP8.5 scenarios, these results show that the RCP8.5 scenarios are having an impact on cocoa growing in Côte d’Ivoire.

Steric Sea Level Change in Twentieth Century Historical Climate Simulation and IPCC-RCP8.5 Scenario Projection: A Comparison of Two Versions of FGOALS Model

To reveal the steric sea level change in 20th century historical climate simulations and future climate change projections under the IPCC＇s Representative Concentration Pathway 8.5 （RCP8.5） scenario, the results of two versions of LASG/IAP＇s Flexible Global Ocean-Atmosphere-Land System model （FGOALS） are analyzed. Both models reasonably reproduce the mean dynamic sea level features, with a spatial pattern correlation coefficient of 0.97 with the observation. Characteristics of steric sea level changes in the 20th century historical climate simulations and RCPS.5 scenario projections are investigated. The results show that, in the 20th century, negative trends covered most parts of the global ocean. Under the RCPS.5 scenario, global-averaged steric sea level exhibits a pronounced rising trend throughout the 21st century and the general rising trend appears in most parts of the global ocean. The magnitude of the changes in the 21st century is much larger than that in the 20th century. By the year 2100, the global-averaged steric sea level anomaly is 18 cm and 10 cm relative to the year 1850 in the second spectral version of FGOALS （FGOALS-s2） and the second grid-point version of FGOALS （FGOALS-g2）, respectively. The separate contribution of the thermosteric and halosteric components from various ocean layers is further evaluated. In the 20th century, the steric sea level changes in FGOALS-s2 （FGOALS-g2） are largely attributed to the thermosteric （halosteric） component relative to the pre-industrial control run. In contrast, in the 21st century, the thermosteric component, mainly from the upper 1000 m, dominates the steric sea level change in both models under the RCPS.5 scenario. In addition, the steric sea level change in the marginal sea of China is attributed to the thermosteric component.

Assessment of Future Climate Change Scenario in Halaba District, Southern Ethiopia

Climate change is one environmental threat that poses great challenges to the future development prospects of Ethiopia. The study used the statistically downscaled daily data in 30-years intervals from the second generation of the Earth System Model (CanESM2) under two Representative Concentration Pathways (RCPs): RCP 4.5 and RCP 8.5 for three future time slices;near-term (2010-2039), mid-century (2040-2069) and end-century (2071-2099) were generated. The observed data of maximum and minimum temperature and precipitation are a good simulation with the modeled data during the calibration and validation periods using the correlation coefficient (R2), the Nash-Sutcliffe efficiency (NSE), and the Root Mean Square Error (RMSE). The projected annual minimum and maximum temperatures are expected to increase by 0.091°C, 0.517°C, and 0.73°C and 0.072°C, 0.245°C, and 0.358°C in the 2020s, 2050s, and 2080s under the intermediate scenario, respectively. Under RCP8.5, the annual minimum and maximum temperatures are expected to increase by 0.192°C, 0.409°C, and 0.708°C, 0.402°C, 4.352°C, and 8.750°C in the 2020s, 2050s, and 2080s, respectively. Besides, the precipitation is expected to increase under intermediate and high emission scenarios by 1.314%, 7.643%, and 12.239%, and 1.269%, 10.316% and 26.298% in the 2020s, 2050s, and 2080s, respectively. Temperature and precipitation are projected to increase in total amounts under all-time slices and emissions pathways. In both emission scenarios, the greatest changes in maximum temperature, minimum temperature, and precipitation are predicted by the end of the century. This implies climate smart actions in development policies and activities need to consider locally downscale expected climatic changes.

SSP-RCP耦合情景的城市局地气候分区模拟--以南京市为例

基于情景的土地利用变化模拟能够展现未来城市的多种可能性,是当前土地覆被变化领域的热点。现有研究地表分类体系中的建设用地无法精确刻画城市内部空间形态,且土地模拟研究中不统一的模拟情景将影响土地模拟结果的可比性,因此,本文采用了国际耦合模式比较计划(CoupledModelIntercomparisonProject,CMIP)最新提出的三种典型SSP-RCP耦合情景,以南京市为研究区,开展了未来近期(2030年)、中期(2060年)和远期(2090年)的局地气候分区(local climate zones,LCZ)时空模拟。结合马尔可夫模型和多目标规划预测未来耦合情景下各LCZ类型的数量需求,并通过未来土地利用变化模拟模型实现LCZ的空间分布模拟。结果表明:①SSP126情景下生态用地(LCZA/B/D/G)得到了有效保护,且建筑用地(LCZ1~6、LCZ8~10)在主城区的扩张得到有效控制。②SSP245情景中,经济发展的同时也顾及了生态环境保护,尽管建筑用地扩张明显,但生态用地(LCZA/B/D/G)的面积仅出现了轻微下降。③SSP585情景建筑用地(LCZ1~6、LCZ8~10)和耕地(LCZ D)扩张态势十分显著;21世纪中、后期的林地(LCZ A、LCZ B)和水体(LCZ G)将遭到严重破坏。本文首次开展了自然与人文双重驱动下的城市LCZ时空模拟,研究成果能够直接应用于城市气候与规划领域。

Climate Change over China in the 21st Century as Simulated by BCC_CSM1.1-RegCM4.0

Driven by the global model,Beijing Climate Center Climate System Model version 1.1(BCC_CSM1.1),climate change over China in the 21st century is simulated by a regional climate model(RegCM4.0)under the new emission scenarios of the Representative Concentration Pathways—RCP4.5 and RCP8.5.This is based on a period of transient simulations from 1950 to2099,with a grid spacing of 50 km.The present paper focuses on the annual mean temperature and precipitation in China over this period,with emphasis on their future changes.Validation of model performance reveals marked improvement of the RegCM4.0 model in reproducing present day temperature and precipitation relative to the driving BCC_CSM1.1 model.Significant warming is simulated by both BCC_CSM1.1 and RegCM4.0,however,spatial distribution and magnitude differ between the simulations.The high emission scenario RCP8.5 results in greater warming compared to RCP4.5.The two models project different precipitation changes,characterized by a general increase in the BCC_CSM1.1,and broader areas with decrease in the RegCM4.0 simulations.

Projected Shifts in Kppen Climate Zones over China and Their Temporal Evolution in CMIP5 Multi-Model Simulations

Previous studies have examined the projected climate types in China by 2100. This study identified the emergence time of climate shifts at a 1 o scale over China from 1990 to 2100 and investigated the temporal evolution of Koppen-Geiger climate classifications computed from CMIP5 multi-model outputs. Climate shifts were detected in transition regions （7%-8% of China＇s land area） by 2010, including rapid replacement of mixed forest （Dwb） by deciduous forest （Dwa） over Northeast China, strong shrinkage of alpine climate type （ET） on the Tibetan Plateau, weak northward expansion of subtropical winter- dry climate （Cwa） over Southeast China, and contraction of oceanic climate （Cwb） in Southwest China. Under all future RCP （Representative Concentration Pathway） scenarios, the reduction of Dwb in Northeast China and ET on the Tibetan Plateau was projected to accelerate substantially during 2010-30, and half of the total area occupied by ET in 1990 was projected to be redistributed by 2040. Under the most severe scenario （RCP8.5）, sub-polar continental winter dry climate over Northeast China would disappear by 2040-50, ET on the Tibetan Plateau would disappear by 2070, and the climate types in 35.9% and 50.8% of China＇s land area would change by 2050 and 2100, respectively. The results presented in this paper indicate imperative impacts of anthropogenic climate change on China＇s ecoregions in future decades.

Climate change and potential distribution of zoonotic cutaneous leishmaniasis in Central Iran: Horizon 2030 and 2050

Objective: To investigate and predict the effects of climate change on the potential distribution of the main vector and reservoir hosts of the disease in Yazd province in the future.Methods: Distribution data for vector and reservoir hosts of zoonotic cutaneous leishmaniasis in Yazd province were obtained from earlier studies conducted in the area.MaxEnt ecological niche modeling was used to predict environmental suitability.BCC-CSM1-1(m) model and two climate change scenarios, RCP 4.5 and RCP 8.5 were used for horizons 2030 and 2050 climate projections.Future projections were based on data of a regional climate change model.Results: With both scenarios in 2030 and 2050, the results of jackknife test indicated that the mean temperature of wettest quarter and temperature annual range had the greatest effect on the model for the vector and the reservoir hosts, respectively.Conclusions: The climate conditions are the major determinants of zoonotic cutaneous leishmaniasis incidence rate in Yazd Province.These climate conditions provide favorable habitats for ease transmission of zoonotic cutaneous leishmaniasis in this endemic area.Habitats suitability for the vector and reservoir will be expanding in the coming years compared with the current conditions, such that, in horizon 2030 & 2050, the probability of the presence of the vector and reservoir within 38 580 and 37 949 km^2, respectively, from Yazd province is above 60%.Moreover, an increase is predicted in the presence of the vector in the western parts and the reservoir in the northern and central parts of the province in the future.Understanding the role of environmental and bioclimatic factors in zoonotic cutaneous leishmaniasis occurrence can provide a guide for policy-makers in the creation and implementation of more effective policies for prevention and control.

Comparison of climate projections between driving CSIRO-Mk3.6.0 and downscaling simulation of RegCM4.4 over China

A 151-year (1950e2100) dynamical downscaling simulation over East Asia is conducted by using the Regional Climate Model RegCM4.4 at 25 km grid spacing, which is nested within CSIRO-Mk3.6.0. Climate changes over China during the 21st century under the RCP4.5 scenario from CSIRO-Mk3.6.0 and RegCM4.4 are analyzed. Both simulations project that continuous warming with large regional variations will occur in the future. The two simulations obtain similar inter-annual fluctuations of regional average warming, with RegCM4.4 obtaining somewhat smaller values than CSIRO-Mk3.6.0. Projected precipitation changes are even more regionally variable than temperature changes. In western China, both models project increased precipitation, while the projections from two models show different regional details in eastern China. In both simulations, projected annual mean precipitation on a national scale does not change significantly due to the contrast changes between dry and wet seasons. To analyze uncertainties of the projected climate change in China, the simulation of RegCM4.4 is compared with a previous simulation of the RegCM3 at the same horizontal resolution. The overall consistency in precipitation change between RegCM3 and RegCM4.4 is projected across western China, while inconsistency is identified in most of eastern China.

Assessing the vulnerability of a forest ecosystem to climate change and variability in the western Mediterranean sub-region of Turkey：future evaluation

This study evaluates the multifactorial spatial modelling used to assess vulnerability of the Du¨ zlerc？am？（Antalya） forest ecosystem to climate change.This was done to produce data,to develop tools to support decisionmaking and the management of vulnerable Mediterranean forest ecosystems affected by climate change,and to increase the ability of these forest ecosystems to adapt to global change.Based on regionally averaged future climate assessments and projected climate indicators,both the study site and the western Mediterranean sub-region of Turkey will probably become associated with a drier,hotter,more continental and more water-deficient climate.This analysis holds true for all future scenarios,with the exception of RCP4.5 for the period from 2015 to 2030.However,the present dry-sub humid climate dominating this sub-region and the study area shows a potential for change towards more dry climatology and for it to become semiarid between 2031 and 2050 according to the RCP8.5 high emission scenario.All the observed and estimated results and assessments summarized in this study show clearly that the densest forest ecosystem in the southern part of the study site,characterized by mainly Mediterranean coniferous and some mixed forest and maquis vegetation,will very likely be influenced by medium and high degrees of vulnerability to future environmental degradation,climate change and variability.

Projected Changes of Palmer Drought Severity Index under an RCP8.5 Scenario

The potential change of drought measured by the Palmer Drought Severity Index （PDSI） is projected by using a coupled climate system model under a Representative Pathway 8.5 （RCP8.5） scenario.The PDSI changes calculated by two potential evapotranspiration algorithms are compared.The algorithm of Thomthwaite equation overestimates the impact of surface temperature on evaporation and leads to an unrealistic increasing of drought frequency.The PM algorithm based on the Penman-Monteith equation is physically reasonably and necessary for climate change projections.The Flexible Global Ocean-Atmosphere-Land System model,Spectral Version 2 （FGOALS-s2） projects an increasing trend of drought during 2051-2100 in tropical and subtropical areas of North and South America,North Africa,South Europe,Southeast Asia,and the Australian continent.Both the moderate drought （PDSI ＜-2） and extreme drought （PDSI ＜-4） areas show statistically significant increasing trends under an RCP8.5 scenario.The uncertainty in the model projection is also discussed.

FUTURE CHANGE OF PRECIPITATION EXTREMES OVER THE PEARL RIVER BASIN FROM REGIONAL CLIMATE MODELS

Based on RegCM4,a climate model system,we simulated the distribution of the present climate(1961-1990)and the future climate(2010-2099),under emission scenarios of RCPs over the whole Pearl River Basin.From the climate parameters,a set of mean precipitation,wet day frequency,and mean wet day intensity and several precipitation percentiles are used to assess the expected changes in daily precipitation characteristics for the 21 st century.Meanwhile the return values of precipitation intensity with an average return of 5,10,20,and 50 years are also used to assess the expected changes in precipitation extremes events in this study.The structure of the change across the precipitation distribution is very coherent between RCP4.5 and RCP8.5.The annual,spring and winter average precipitation decreases while the summer and autumn average precipitation increases.The basic diagnostics of precipitation show that the frequency of precipitation is projected to decrease but the intensity is projected to increase.The wet day percentiles(q90 and q95) also increase,indicating that precipitation extremes intensity will increase in the future.Meanwhile,the5-year return value tends to increase by 30%-45%in the basins of Liujiang River,Red Water River,Guihe River and Pearl River Delta region,where the 5-year return value of future climate corresponds to the 8-to 10-year return value of the present climate,and the 50-year return value corresponds to the 100-year return value of the present climate over the Pearl River Delta region in the 2080 s under RCP8.5,which indicates that the warming environment will give rise to changes in the intensity and frequency of extreme precipitation events.

Bayesian multi-model projections of extreme hydroclimatic events under RCPs scenarios

A Bayesian multi-model inference framework was used to assess the changes in the occurrence of extreme hydroclimatic events in four major river basins in China （i.e., Liaohe River Basin, Yellow River Basin, Yangtze River Basin, and Pearl River Basin） under RCP2.6, RCP4.5, and RCP8.5 scenarios using multiple global climate model projections from the IPCC Fifth Assessment Report. The results projected more summer days and fewer frost days in 2006-2099. The ensemble prediction shows the Pearl River Basin is projected to experience more summer days than other basins with the increasing trend of 16.3, 38.0, and 73.0 d per 100 years for RCP2.6, RCP4.5 and RCP8.5, respectively. Liaohe River Basin and Yellow River Basin are forecasted to become wetter and warmer with the co-occurrence of increases in summer days and wet days. Very heavy precipitation days （R20, daily precipitation ≥20 mm） are projected to increase in all basins. The R20 in the Yangtze River Basin are projected to have the highest change rate in 2006-2099 of 1.8, 2.5, and 3.8 d per 100 years for RCP2.6, RCP4.5 and RCP8.5, respectively.

Impacts of Climate Change on the Hydrology of a Small Brazilian Headwater Catchment Using the Distributed Hydrology-Soil-Vegetation Model

Climate change is one of the greatest issues for human society. The objective of this study is to assess the impacts of future climate change on seasonal average discharge and monthly water budget in a small headwater catchment, located on the Grande River basin, in Minas Gerais, Brazil. The assessment is carried out using the hydrology model, DHSVM. The atmospheric forcing to drive the Distributed Hydrology-Soil-Vegetation Model (DHSVM) is derived from the downscaling of the HadGEM2-ES projections by the Eta Regional Climate Model, at 5-km high resolution. The projections assume the RCP4.5 and RCP8.5 IPCC AR5 emission scenarios. Baseline period was taken between 1961 and 1990. The projections are assessed in three time slices (2011-2040, 2041-2070 and 2071-2099). The climate change is assessed in time slices of 30 years and in comparison against the baseline period to evaluate the hydrological changes in the catchment. The results showed differences in the hydrological behavior between the emission scenarios and though time slices. Reductions in the magnitude of the seasonal average discharge and monthly water budget may alter the water availability. Under the RCP4.5 scenario, results show greater reductions in the water availability in the first time slice, whereas under RCP8.5 scenario greater reductions are indicated in the third time slice.

The Projected Changes of Precipitations over Niger Under the Scenarios RCP 4.5 and RCP 8.5

The socio-economic activities of Niger rely on agriculture which is strongly affected by changes in precipitation during the rainy season.The ultimate aim of this study is to assess the projected changes of precipitation over Niger under the Representative Concentration Pathways(RCP)scenarios 4.5(RCP 4.5)and RCP 8.5 using multi-RCM(Multi-Regional Climate)model approach.The observation data are from CHIRPS(Climate Hazards Group InfraRed Precipitation with Station)and the RCMs are from the SMHI(Swedish Meteorological and Hydrological Institute)model(RCA4)driven by ten(10)different GCMs(General Circulation Model)(e.g.,CCCma,CSIRO,ICHEC,IPSL,MIROC,MOHC-HadGEM2,MPI,NCC-NorESM1,NOOA,and NRCM)within the framework of CORDEX(Coordinated Regional Climate Downscaling Experiment)Africa experiment.The reference and projections periods in this study are respectively 1981-2005 for the present and 2011-2100 for the near,medium and far future divided into three periods,2011 to 2040(P1),2041 to 2070(P2)and 2071 to 2100(P3).The methodology used,consists of assessing the performance of the multi-RCMs of RCA4 model(with respect of CHIRPS)in simulating the precipitations changes by computing the spatial distribution and anomalies of precipitations;and their indices of RMSE(Root Mean Square Error),the bias,SPI(Standardized Precipitation Anomaly Index),correlation coefficient,statistical t-test,spatial evolution rate and the rate of temporal change.After the validation of the multi-RCMs RCA4 models,the ensemble mean of the models is used to assess the projected changes of precipitations over Niger in the future.The results show that most of the multi-RCMs capture the four climatic zone except for IPSL.While the ensemble mean of the models simulates(as compared to CHIRPS)more accurately the monthly,annual precipitations anomalies and their indices than individual’s models in the reference period,some RCMs(e.g.,CSIRO-IPSL and CCCma-HadGEM)poorly reproduce them.The projected changes of precipitations indicate for the scenario RCP 4.5 respectively a moderately surplus of precipitation years in the period P1 and moderately deficit years in the period P2 while the period P3 shows a small upward precipitation trend.In contrary,for the scenario RCP 8.5,all the three periods(P1,P2 and P3)indicate an intensification of precipitation leading to a longer wet period which may lead to extreme precipitations and flooding.Moreover,both scenarios have projected an increase of total monthly precipitation in May and September and a decrease in July and August respectively which will likely lead to an early onset and late cessation of the rainy season;and a shift of the peak of the rainy season.Therefore,this study shows the need of a monitoring system for the projected changes of precipitation in the near future to anticipate urgent action in wet/dry periods to adapt to a changing climate.

Change in Climate Indices Using Bias-Adjusted CMIP5 Models: The Case Study of the Fatick Region, Senegal

This study analyses change in rainfall and temperature indices by 2035 and 2050 in Senegal, with a focus on the Fatick region. These parameters are crucial for understanding the impacts of anthropogenic climate change on some vital socio-economic sectors such as agriculture and water resources in this region. To this end, a multi model ensemble mean of 21 bias-adjusted global climate models participating in CMIP5 has been used. We considered two Representative Concentration Pathways (RCP4.5 and RCP8.5). The results indicate an increase of 0.7˚C for maximum and minimum temperature by 2035 compared to the reference period (1976 - 2005). By 2050, an increase of 1.4˚C (2˚C) is projected for RCP4.5 (RCP8.5). These increases in temperature are statistically significant at the 90% confidence level. Conversely, the mean rainy season length decreases from 95 to 85 days by 2035 and less than 80 days by 2050. These decreases in rainy season length are mainly due to a delayed rainy season onset by 2035 and 2050, with the ensemble mean projecting an onset in the second half of July by 2050 instead of around the middle of June. The changes in both the onset and the length of the rainy season are significant at the 90% confidence level. Our results show a slight decrease in seasonal cumulated total rainfall by 2035 and 2050. However, we note a slight increase in seasonal cumulated extreme rainfall. These future changes in climate indices could induce yield reduction and water resources availability. To reduce yield losses, it would be interesting to adopt longer season varieties and also diversify income-generating activities. Concerning water resources, many actions could be done such as carrying out water retention works, treatment and reuse of non-conforming water for agriculture and livestock to reduce pressure on the resource.

西南地区生态系统服务供需历史变化与SSP-RCP情景预测

生态系统服务的供需平衡对实现可持续发展至关重要。为了更好地了解过去气候变化和社会经济发展对生态系统服务的影响,并对未来不同气候和社会经济发展情景做出正确响应,有必要对生态系统服务的供需变化进行系统的评估和预测。研究对我国西南地区2000、2010、2015年的水源涵养、食物生产和固碳3项生态系统服务的供给和需求进行了定量的空间评估,然后基于IPCC(Intergovernmental Panel on Climate Change)提出的社会经济发展和气候变化联合情景框架,即SSP-RCP情景(Shared Socio-economic Pathways-Representative Concentration Pathways),对此3项生态系统服务在未来2035年和2050年的供给和需求进行了SSP1-RCP2.6、SSP2-RCP4.5、SSP4-RCP6.0和SSP5-RCP8.5 4个情景下的预测。结果显示,西南地区水源涵养和固碳服务的供给和需求具有显著的空间不匹配特征,且其需求从2000—2015年分别增长了11.49%和252.41%。根据SSP-RCP情景预测结果,水源涵养供给服务受到不同情景下气候变化的影响最大,而固碳服务面临的不确定性最大。4个情景中,SSP5-RCP8.5情景下各项生态系统服务从2035—2050年的变化最为剧烈,而SSP1-RCP2.6和SSP2-RCP4.5情景下各项生态系统服务的变化相对较小。采用了一套系统地评估生态系统服务供给和需求的方法,对生态系统服务供需的定量化研究具有指示意义,并创新地应用了SSP-RCP情景框架,综合考虑了未来不同情景下的气候变化和社会经济发展,对生态系统服务供需进行了预测。

黄河流域未来极端气候事件变化趋势评估

极端气候事件会对陆地生态系统服务功能以及人类社会生活造成严重影响。针对GFDL、FGOALS和CCSM4这3种CMIP5气候模式,对RCP2.6、RCP4.5、RCP8.5未来情景下的黄河流域极端气候时空变化特征进行研究。结果表明:RCP2.6、RCP4.5、RCP8.5情景下流域日最高气温的上升速率分别为0.052、0.170、0.470℃/10 a,日最低气温的上升速率分别为0.029、0.170、0.460℃/10 a。日最高气温和日最低气温的空间分布规律呈现出一致性,从黄河上游河源区向中下游呈上升趋势。未来情景下黄河流域整体年降水量呈弱增加趋势,到21世纪后期,高温室气体排放情景下年降水量的增幅变大。

Assessment of climate damage in China based on integrated assessment framework

Developing a localized and consistent model framework for climate loss and damage assessment is crucial for the policy-making of climate change mitigation and adaptation.This study introduces a comprehensive,multidisciplinary Integrated Assessment Model(IAM)framework for evaluating climate damage in China,utilizing BCC-SESM climate model and FUND sectoral climate damage model under the SSP2-RCPs scenario.Employing a bottom-up approach,the research estimates climate damage across eight major sectors,recalibrates sectoral climate damage functions and parameters for China,and elucidates distinctions among direct climate loss,market climate loss,and aggregate climate loss.The findings reveal that the total climate damage function for China follows a quadratic pattern in response to temperature rise.By 2050,the estimated climate damage is projected to be 5.4%,5.7%,and 8.2%of GDP under RCP2.6,RCP4.5,and RCP8.5,respectively.Additionally,both direct and market climate losses are projected to remain below 2%of GDP by 2050,while the aggregate climate loss could reach as high as 8.2%,which is predominantly attributed to non-market sectors.From a sectoral perspective,under the RCP8.5 scenario,human health damage constitutes the largest share(61.9%)of the total climate loss by 2050,followed by sea-level rise damage(18.6%).This study sheds lights on the adaptation policy that should attach importance to the non-market sectors,particularly focusing on human health and sea-level rise.

气候变化对淮河流域水资源及极端洪水事件的影响

利用法国国家气象研究中心气候模型(Centre National de Recherches Météorologiques Climate Model,CNRM)典型代表性浓度路径(Representative Concentration Pathway,RCP)情景资料和可变下渗容量模型(Variable Infiltration Capacity Model,VIC),分析了淮河流域未来气温、降水、水资源及可能洪水的变化趋势。结果表明,淮河流域未来气温将持续升高,RCP2.6、RCP4.5和RCP8.5情景下未来2021~2050年较基准期(1961~1990年)升幅分别约为1.13℃、1.10℃和1.35℃;流域降水可能呈现略微增加趋势,3种排放情景下2021~2050年降水较基准期将分别增加5.81%、8.26%和6.94%;VIC模型在淮河流域具有较好的适用性,能较好地模拟淮河流域的水文过程,在率定期和检验期,模型对王家坝站和蚌埠站模拟的水量相对误差都在5%以内,日径流过程的Nash-Sutcliffe模型效率系数(NSE)在0.70以上,月径流过程的NSE达到0.85以上。气候变化将导致淮河流域水文循环强度增加,流域水资源总体将可能呈增加趋势,王家坝站和蚌埠站断面洪水事件的发生可能性将增大。

CMIP5模式对中国地区气温模拟能力评估与预估

利用第五次国际耦合模式比较计划(CMIP5)中29个气候模式的气温模拟结果,评估了各模式对中国地区年平均气温的模拟能力,对未来不同典型浓度路径(RCPs)下中国地区气温的可能变化给出了预估。结果表明:各模式能较好地模拟过去100多年中国地区增温趋势和年平均气温的空间分布,从模式间标准差来看,各模式对中国中部、南部气温模拟具有较高的一致性。利用相对均方根误差分析了各模式的模拟能力,对于多时间尺度(月、年)气温的气候平均态,有7个模式表现良好,高于中等水平,5个模式的模拟能力低于中等水平,模式集合平均值的模拟效果优于大多数单个模式。根据29个模式的评估结果,使用模拟性能相对较好的模式分析了未来不同排放情景下中国地区气温变化,21世纪前期,不同排放情景之间的预估结果差别较小,21世纪中期各情景之间的差别逐渐增大,到21世纪后期,3种排放情景的升温差别明显增大。