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1.
Projections of annual mean air temperature and precipitation over the globe and in China during the 21st century by the BCC Climate System Model BCC_CSM1.0 
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下载免费PDF全文 Evaluating the projection capability of climate models is an important task in climate model development and climate change studies. The projection capability of the Beijing Climate Center (BCC) Climate System Model BCC CSM1.0 is analyzed in this study. We focus on evaluating the projected annual mean air temperature and precipitation during the 21st century under three emission scenarios (Special Report on Emission Scenarios (SRES) B1, A1B, and A2) of the BCC CSM1.0 model, along with comparisons with 22 CMIP3 (Coupled Model Intercomparison Project Phase 3) climate models. Air temperature averaged both globally and within China is projected to increase continuously throughout the 21st century, while precipitation increases intermittently under each of the three emission scenarios, with some specific temporal and spatial characteristics. The changes in globally-averaged and China-averaged air temperature and precipitation simulated by the BCC CSM1.0 model are within the range of CMIP3 model results. On average, the changes of precipitation and temperature are more pronounced over China than over the globe, which is also in agreement with the CMIP3 models. The projection capability of the BCC CSM1.0 model is comparable to that of other climate system models. Furthermore, the results reveal that the climate change response to greenhouse gas emissions is stronger over China than in the global mean, which implies that China may be particularly sensitive to climate change in the 21st century. 相似文献
2.
Evaluating the projection capability of climate models is an important task in climate model development
and climate change studies. The projection capability of the Beijing Climate Center (BCC) Climate System
Model BCC_CSM1.0 is analyzed in this study. We focus on evaluating the projected annual mean air
temperature and precipitation during the 21st century under three emission scenarios (Special Report on
Emission Scenarios (SRES) B1, A1B, and A2) of the BCC_CSM1.0 model, along with comparisons with
22 CMIP3 (Coupled Model Intercomparison Project Phase 3) climate models. Air temperature averaged
both globally and within China is projected to increase continuously throughout the 21st century, while
precipitation increases intermittently under each of the three emission scenarios, with some specific temporal
and spatial characteristics. The changes in globally-averaged and China-averaged air temperature and
precipitation simulated by the BCC_CSM1.0 model are within the range of CMIP3 model results. On
average, the changes of precipitation and temperature are more pronounced over China than over the globe,
which is also in agreement with the CMIP3 models. The projection capability of the BCC_CSM1.0 model is
comparable to that of other climate system models. Furthermore, the results reveal that the climate change
response to greenhouse gas emissions is stronger over China than in the global mean, which implies that
China may be particularly sensitive to climate change in the 21st century. 相似文献
3.
We assessed the potential effects of a greenhouse gas-induced global climate change on the hydrology and vegetation of a semi-permanent prairie wetland using a spatially-defined, rule-based simulation model. An 11-yr simulation was run using current versus enhanced greenhouse gas climates. Projections of climatic change were from the Goddard Institute for Space Studies (GISS) general circulation model. Simulations were also run using a range of temperature (+2 and +4 °C) and precipitation change values (–20, –10, 0, +10, +20%) to determine the responsiveness of wetland vegetation and hydrology to a variety of climate scenarios.Maximum water depths were significantly less under the enhanced greenhouse gas scenario than under the current climate. The wetland dried in most years with increased temperature and changes in precipitation. Simulations also revealed a significant change in the vegetation, from a nearly balanced emergent cover to open water ratio to a completely closed basin with no open water areas. Simulations over a range of climate change scenarios showed that precipitation changes (particularly increases) had a greater impact on water levels and cover ratios when the temperature increase was moderate (+2 °C).These potential changes in wetland hydrology and vegetation could result in a dramatic decline in the quality of habitat for breeding birds, particularly waterfowl. Continued research on climate and wetland modeling is needed. 相似文献
4.
We investigated changes to precipitation and temperature of Alberta for historical and future periods. First, the Mann-Kendall test and Sen’s slope were used to test for historical trends and trend magnitudes from the climate data of Alberta, respectively. Second, the Special Report on Emissions Scenarios (SRES) (A1B, A2, and B1) of CMIP3 (Phase 3 of Coupled Model Intercomparison Project), projected by seven general circulation models (GCM) of the Intergovernmental Panel on Climate Change (IPCC) for three 30 years periods (2020s, 2050s, and 2080s), were used to evaluate the potential impact of climate change on precipitation and temperature of Alberta. Third, trends of projected precipitation and temperature were investigated, and differences between historical versus projected trends were estimated. Using the 50-km resolution dataset from CANGRD (Canadian Grid Climate Data), we found that Alberta had become warmer and somewhat drier for the past 112 years (1900–2011), especially in central and southern Alberta. For observed precipitation, upward trends mainly occurred in northern Alberta and at the leeward side of Canadian Rocky Mountains. However, only about 13 to 22 % of observed precipitation showed statistically significant increasing trends at 5 % significant level. Most observed temperature showed significant increasing trends, up to 0.05 °C/year in DJF (December, January, and February) in northern Alberta. GCMs’ SRES projections indicated that seasonal precipitation of Alberta could change from ?25 to 36 %, while the temperature would increase from 2020s to 2080s, with the largest increase (6.8 °C) in DJF. In all 21 GCM-SRES cases considered, precipitation in both DJF and MAM (March, April, and May) is projected to increase, while temperature is consistently projected to increase in all seasons, which generally agree with the trends of historical precipitation and temperature. The SRES A1B scenario of CCSM3 might project more realistic future climate for Alberta, where its water resources can become more critical in the future as its streamflow is projected to decrease continually in the future. 相似文献
5.
Towards the Construction of Climate Change Scenarios 总被引：3，自引：2，他引：1
John F. B. Mitchell T. C. Johns M. Eagles W. J. Ingram R. A. Davis 《Climatic change》1999,41(3-4):547-581
Climate impacts assessments need regional scenarios of climate change for a wide range of projected emissions. General circulation models (GCMs) are the most promising approach to providing such information, but as yet there is considerable uncertainty in their regional projections and they are still too costly to run for a large number of emission scenarios. Simpler models have been used to estimate global-mean temperature changes under a range of scenarios. In this paper we investigate whether a fixed pattern from a GCM experiment scaled by global-mean temperature changes from a simple model provides an acceptable estimate of the regional climate change over a range of scenarios. Changes estimated using this approximate approach are evaluated by comparing them with results from ensembles of a coupled ocean-atmosphere model. Five specific emissions scenarios are considered. For increases in greenhouse gases only, the 'error' in annual mean temperature for the cases considered is smaller than the sampling error due to the model's internal variability. The method may break down for scenarios of stabilisation of concentrations, because the patterns change as the model approaches equilibrium. The inclusion of large local perturbations due to sulphate aerosols can lead to significant deviations of the temperature pattern from that obtained using greenhouse gases alone. Combining separate patterns for the responses to greenhouse gases and aerosols may improve the accuracy of approximation. Finally, the accuracy of the scaling approach is more difficult to assess for deriving changes in regional precipitation because many of the regional changes are not statistically significant in the climate change projections considered here. If precipitation changes are only marginally significant in other models, the apparent disagreement between different models may be as much due to sampling error as to genuine differences in model response. 相似文献
6.
Uncertainty in future climate change presents a key challenge for adaptation planning. In this study, uncertainty arising from internal climate variability is investigated using a new 40-member ensemble conducted with the National Center for Atmospheric Research Community Climate System Model Version 3 (CCSM3) under the SRES A1B greenhouse gas and ozone recovery forcing scenarios during 2000–2060. The contribution of intrinsic atmospheric variability to the total uncertainty is further examined using a 10,000-year control integration of the atmospheric model component of CCSM3 under fixed boundary conditions. The global climate response is characterized in terms of air temperature, precipitation, and sea level pressure during winter and summer. The dominant source of uncertainty in the simulated climate response at middle and high latitudes is internal atmospheric variability associated with the annular modes of circulation variability. Coupled ocean-atmosphere variability plays a dominant role in the tropics, with attendant effects at higher latitudes via atmospheric teleconnections. Uncertainties in the forced response are generally larger for sea level pressure than precipitation, and smallest for air temperature. Accordingly, forced changes in air temperature can be detected earlier and with fewer ensemble members than those in atmospheric circulation and precipitation. Implications of the results for detection and attribution of observed climate change and for multi-model climate assessments are discussed. Internal variability is estimated to account for at least half of the inter-model spread in projected climate trends during 2005–2060 in the CMIP3 multi-model ensemble. 相似文献
7.
We compared regional biases and transient doubled CO2 sensitivities of nine coupled atmosphere-ocean general circulation models (GCMs) from six international climate modeling
groups. We evaluated biases and responses in winter and summer surface air temperatures and precipitation for seven subcontinental
regions, including those in the 1990 Intergovernmental Panel on Climate Change (IPCC) Scientific Assessment. Regional biases
were large and exceeded the variance among four climatological datasets, indicating that model biases were not primarily due
to uncertainty in observations. Model responses to altered greenhouse forcing were substantial (average temperature change=2.7±0.9 °C, range of precipitation change =−35 to +120% of control). While coupled models include more climate system feedbacks than
earlier GCMs implemented with mixed-layer ocean models, inclusion of a dynamic ocean alone did not improve simulation of long-term
mean climatology nor increase convergence among model responses to altered greenhouse gas forcing. On the other hand, features
of some of the coupled models including flux adjustment (which may have simply masked simulation errors), high horizontal
resolution, and estimation of screen height temperature contributed to improved simulation of long-term surface climate. The
large range of model responses was partly accounted for by inconsistencies in forcing scenarios and transient-simulation averaging
periods. Nonetheless, the models generally had greater agreement in their sensitivities than their controls did with observations.
This suggests that consistent, large-scale response features from an ensemble of model sensitivity experiments may not depend
on details of their representation of present-day climate.
Received: 9 September 1996 / Revised: 31 July 1997 相似文献
8.
This is the second of the two-part paper series on the analysis and evaluation of the Fifth phase of Coupled Model Intercomparison Project (CMIP5) simulation of contemporary climate as well as IPCC, AR5 Representative Concentrations Pathways (RCP), 4.5 and 8.5 scenarios projections of the Greater Horn of Africa (GHA) Climate. In the first part (Otieno and Anyah in Clim Dyn, 2012) we focused on the historical simulations, whereas this second part primarily focuses on future projections based on the two scenarios. Six Earth System Models (ESMs) from CMIP5 archive have been used to characterize projected changes in seasonal and annual mean precipitation, temperature and the hydrological cycle by the middle of twenty-first century over the GHA region, based on IPCC, 5th Assessment Report (AR5) RCP4.5 and RCP8.5 scenarios. Nearly all the models outputs analyzed reproduce the correct mean annual cycle of precipitation, with some biases among the models in capturing the correct peak of precipitation cycle, more so, March–April–May (MAM) seasonal rainfall over the equatorial GHA region. However, there is significant variation among models in projected precipitation anomalies, with some models projecting an average increase as others project a decrease in precipitation during different seasons. The ensemble mean of the ESMs indicates that the GHA region has been experiencing a steady increase in both precipitation and temperature beginning in the early 1980s and 1970s respectively in both RCP4.5 and RCP8.5 scenarios. Going by the ensemble means, temperatures are projected to steadily increase uniformly in all the seasons at a rate of 0.3/0.5 °C/decade under RCP4.5/8.5 scenarios over northern GHA region leading to an approximate temperature increase of 2/3 °C by the middle of the century. On the other hand, temperatures will likely increase at a rate of 0.3/0.4 °C/decade under RCP4.5/8.5 scenarios in both equatorial and southern GHA region leading to an approximate temperature increase of 2/2.5 °C by the middle of twenty-first century. Nonetheless, projected precipitation increase varied across seasons and sub-regions. With the exception of the equatorial region, that is projected to experience precipitation increase during DJF season, most sub-regions are projected to experience precipitation increase within their peak seasons, with the highest rate of increase experienced during DJF and OND seasons over southern and equatorial GHA regions respectively. Notably, as precipitation increases, the deficit (E < P) between evaporation (E) and precipitation (P) increased over the years, with a negatively skewed distribution. This generally implies that there is a high likelihood of an increased deficit in local moisture supply. This remarkable change in the general hydrological cycle (i.e. deficit in local moisture) is projected to be also coincident with intensified westerly anomaly influx from the Congo basin into the region. However, better understanding of the detailed changes in hydrological cycle will require comprehensive water budget analyses that require daily or sub-daily variables, and was not a specific focus of the present study. 相似文献
9.
This paper describes the regional climate change scenarios that are recommended for use in the U.S. Country Studies Program (CSP) and evaluates how well four general circulation models (GCMs) simulate current climate over Europe. Under the umbrella of the CSP, 50 countries with varying skills and experience in developing climate change scenarios are assessing vulnerability and adaptation. We considered the use of general circulation models, analogue warm periods, and incremental scenarios as the basis for creating climate change scenarios. We recommended that participants in the CSP use a combination of GCM based scenarios and incremental scenarios. The GCMs, in spite of their many deficiencies, are the best source of information about regional climate change. Incremental scenarios help identify sensitivities to changes in a particular meteorological variable and ensure that a wide range of regional climate change scenarios are considered. We recommend using the period 1951–1980 as baseline climate because it was a relatively stable climate period globally. Average monthly changes from the GCMs and the incremental changes in climate variables are combined with the historical record to produce scenarios. The scenarios do not consider changes in interannual, daily, or subgrid scale variability. Countries participating in the Country Studies Program were encouraged to compare the GCMs' estimates of current climate with actual long-term climate means. In this paper, we compare output of four GCMs (CCCM, GFDL, UKMO, and GISS) with observed climate over Europe by performing a spatial correlation analysis for temperature and precipitation, by statistically comparing spatial patterns averaged climate estimates from the GCMs with observed climate, and by examining how well the models estimate seasonal patterns of temperature and precipitation. In Europe, the GISS and CCCM models best simulate current temperature, whereas the GISS and UK89 models, and the CCCM model, best simulate precipitation in defined northern and southern regions, respectively. 相似文献
10.
基于RegCM4.4高分辨率区域气候模式数据和华中区域1986—2005年逐日气象观测资料,在对模式模拟性能检验的基础上,对中国华中区域未来不同时期、1.5℃和2℃温升阈值下气候变化进行预估。结果表明：模拟结果能较准确反映出区域气温、降水年内变化特征及空间分布特征;与观测值相比,气温模拟值偏低、降水模拟值偏大;与1986—2005年相比,未来RCP4.5温室气体排放情景下2020—2098年中国华中区域气温增幅为2.1℃,且以0.3℃/10 a的趋势增加,降水量无明显变化趋势;远期（2080—2098年）气温将上升2.88℃,降水将增加7.58%,均高于近期（2020—2035年）和中期（2046—2065年）;1.5℃温升情景下华中区域气温上升1.22℃,降水增加1.93%;2℃温升情景下,华中区域气温上升1.36℃,降水增加3.57%。 相似文献
11.
基于政府间气候变化委员会(IPCC)排放情景特别报告(SRES)A2和B2温室气体排放方案下全球海气耦合模式模拟结果,分析了未来半个世纪中国江淮流域夏季降水变化趋势,发现江淮流域在经历21世纪开始10年降水偏多时期后,从2010年开始该地区将经历一段降水偏少的时期,在温室气体和SO2排放量较多的A2方案下,该时期将维持较长时间.这些地区夏季降水的减少与夏季西北太平洋副热带高压环流的减弱东撤有关,由此伴随这些地区夏季风和对流层中大气上升运动的减弱,而西北太平洋副热带高压环流的减弱东撤与北太平洋海表面南高北低的温度梯度的减小有关. 相似文献
12.
A monthly water balance (WB) model was developed for the Yukon River Basin (YRB). The WB model was calibrated using mean monthly values of precipitation and temperature derived from the Precipitation-elevation Regression on Independent Slopes Model (PRISM) data set and by comparing estimated mean monthly runoff with runoff measured at Pilot Station, Alaska. The calibration procedure used the Shuffled Complex Evolution global search. Potential hydrologic effects of climate change were assessed for the YRB by imposing changes in precipitation and temperature derived from selected Inter-governmental Panel for Climate Change (IPCC) climate simulations. Scenarios from five general circulation model (GCM) simulations were used to provide a range of potential changes. Results from the scenarios indicate an increase in annual runoff in the twenty-first century for the YRB with simulated increases in precipitation having the greatest effect on increases in runoff. Simulated increases in temperature were found to alter the timing of snow accumulation and melt. 相似文献
13.
利用日本东京大学气候系统研究所、日本环境研究所和日本地球环境研究中心联合开发的海气耦合模式MIROC3.2，研究了全球变暖对ENSO年际变率的影响。该模式较好地模拟了ENSO循环的不同阶段表层和次表层海水温度变化，海表温度最大振幅出现在120°W以东，与观测一致，表明模式可以较好反映热带地区大气、海洋的动力、热力特征。研究还比较了控制试验和CO2浓度年增长1%的瞬时试验，结果表明，在全球变暖的大环境下ENSO事件发生频率没有显著变化，但ENSO事件强度增大，年际变率变大；热带太平洋呈现整体增暖趋势，表层温度尤其是热带中太平洋地区温度升高显著。敏感性分析表明，年际ENSO变率的振幅增大的主要贡献来自于海洋。海水增温导致热带太平洋海温垂直梯度增大，在热带西太平洋海温垂直温度梯度变化最为明显；次表层海温对单位大气风应力变化的响应大于表层海温响应。当这种响应与热带太平洋赤道地区径向温度梯度变化的共同作用导致温室效应下ENSO振幅增大。 相似文献
14.
Climate Changes in the 21st Century over the Asia-Pacific Region Simulated by the NCAR CSM and PCM 总被引：3，自引：0，他引：3
The Climate System Model (CSM) and the Parallel Climate Model (PCM), two coupled global climate models without flux adjustments recently developed at NCAR, were used to simulate the 20th century climate using historical greenhouse gas and sulfate aerosol forcing. These simulations were extended through the 21st century under two newly developed scenarios, a business-as-usual case (BAU, CO2≈710 ppmv in 2100) and a CO2 stabilization case (STA550, CO2≈540 ppmv in 2100). The simulated changes in temperature, precipitation, and soil moisture over the Asia-Pacific region (10°-60°N, 55°-155°E) are analyzed, with a focus on the East Asian summer monsoon rainfall and climate changes over the upper reaches of the Yangtze River. Under the BAU scenario, both the models produce surface warming of about 3-5℃ in winter and 2-3℃ in summer over most Asia. Under the STA550 scenario, the warming is reduced by 0.5-1.0℃ in winter and by 0.5℃ in summer. The warming is fairly uniform at the low latitudes and does not induce significant changes in the zonal mean Hadley circulation over the Asia-Pacific do main. While the regional precipitation changes from single CSM integrations are noisy, the PCM ensemble mean precipitation shows 10%-30% increases north of ～ 30°N and ～ 10% decreases south of ～ 30°N over the Asia-Pacific region in winter and 10%-20% increases in summer precipitation over most of the region. Soil moisture changes are small over most Asia. The CSM single simulation suggests a 30% increase in river runoff into the Three Gorges Dam, but the PCM ensemble simulations show small changes in the runoff. 相似文献
15.
Sensitivity of evapotranspiration in a wheat field,a forest,and a grassland to changes in climate and direct effects of carbon dioxide 总被引：2，自引：1，他引：2
Micrometeorological and physiological measurements were used to develop Penman-Monteith models of evapotranspiration for a wheat field in eastern Nebraska, a forest in Tennessee, and a grassland in east-central Kansas. The model fit the measurements well over the periods of observation. Model sensitivities to changes in climatic and physiological parameters were then analyzed. The range of changes considered was established from recent general circulation model output and from review of recent plant physiological research. Finally, climate change scenarios produced by general circulation models for the locations and seasons matching the observed data were applied to the micrometeorological models. Simulation studies show that when all climatic and plant factors are considered, evapotranspiration estimates can differ greatly from those that consider only temperature. Depending on ecosystem and on climate and plant input used, evapotranspiration can differ from the control (no climate or plant change) by about -20 to +40%. 相似文献
16.
Climate is one factor that determines the potential range of malaria. As such, climate change may work with or against efforts
to bring malaria under control. We developed a model of future climate suitability for stable Plasmodium falciparum malaria transmission in Zimbabwe. Current climate suitability for stable malaria transmission was based on the MARA/ARMA
model of climatic constraints on the survival and development of the Anopheles vector and the Plasmodium falciparum malaria parasite. We explored potential future geographic distributions of malaria using 16 projections of climate in 2100.
The results suggest that, assuming no future human-imposed constraints on malaria transmission, changes in temperature and
precipitation could alter the geographic distribution of malaria in Zimbabwe, with previously unsuitable areas of dense human
population becoming suitable for transmission. Among all scenarios, the highlands become more suitable for transmission, while
the lowveld and areas with low precipitation show varying degrees of change, depending on climate sensitivity and greenhouse
gas emission stabilization scenarios, and depending on the general circulation model used. The methods employed can be used
within or across other African countries. 相似文献
17.
We investigate the effect of climate change on crop productivity in Africa using satellite derived data on land use and net primary productivity (NPP) at a small river basin scale, distinguishing between the impact of local and upper-catchment weather. Regression results show that both of these are determining factors of local cropland productivity. These estimates are then combined with climate change predictions obtained from two general circulation models (GCMs) under two greenhouse gas emissions (GHG) assumptions to evaluate the impact of climate change by 2100. For some scenarios significant decreases are predicted over the northern and southern parts of Africa. 相似文献
18.
ECHAM4/OPYC3海气耦合模式对东亚季风年循环及其未来变化的模拟 总被引：8，自引：0，他引：8
德国马普研究所海气耦合摸式ECHAM4/OPYC3对东亚地区2 m温度年循环的模拟尽管有一些偏差,但还是相当成功的.其模拟的东亚夏季风偏弱,而冬季风偏强,此偏差可能与2 m温度以及西太平洋副热带高压模拟偏差有关.该模式模拟的东亚季风区夏季降水量偏弱,这与上述夏季风环流的模拟结果是一致的.该模式较好地抓住了华北地区经向环流和降水量的年循环特征.利用最新的温室气体和SO2排放方案,即政府间气候变化委员会(IPCC)排放方案特别报告(SRES)的A2和B2方案,通过该模式111年的积分结果讨论了东亚季风气候在21世纪后30年中的变化,其主要结果为:全球变暖导致夏季海陆温差增大和冬季海陆温差减弱,进而使东亚季风环流在夏季加强,冬季减弱.长江流域和华北地区的夏季降水量显著增强,而后者的增强更为显著,使得东亚季风区的夏季多雨区向北延伸;东亚季风区9月份的降水量在两个方案中都显著增加,说明在全球变暖条件下东亚季风区的多雨季节将延迟一个月. 相似文献
19.
Sin Chan Chou Andr&#; de Arruda Lyra Jorge Lu&#;s Gomes Daniel Andr&#;s Rodriguez Minella Alves Martins Nicole Costa Resende Priscila da Silva Tavares Claudine Pereira Dereczynski Isabel Lopes Pilotto Alessandro Marques Martins Lu&#;s Felipe Alves de Carvalho Jos&#; Luiz Lima Onofre Idal&#;cio Major Manuel Penhor Ad&#;rito Santana 《Climate Dynamics》2020,54(9):4021-4042
Sao Tome and Principe is a small insular African country extremely vulnerable to rising sea levels and impacts such as inundation, shore line change, and salt water intrusion into underground aquifers. Projections of climate change have considered coarse model resolutions. The objective of this work is to dynamically downscale the global model projections to 4-km resolution and to assess the climate change in the Sao Tome and Principe islands. The global climate projections are provided by the Canadian Earth System Model under two Representative Concentration Pathways greenhouse gas scenarios, RCP4.5 and RCP8.5. The downscaling is produced by the Eta regional climate model. The baseline period is taken between 1971 and 2000, and the future climate period is taken between 2041 and 2070. The 2-m temperature simulations show good agreement with station data. The model simulates temperature more accurately than precipitation. The precipitation simulations systematically show underestimation and delay of the rainy and the dry seasons by about 1 month, a feature inherited from the global climate model. In the middle of the 21st century, projections show the strongest warming in the elevated parts of the Sao Tome Island, especially in February under RCP8.5. Warmer nights and warmer days become more frequent in the islands when compared with those in the present. While under RCP4.5, precipitation increases in the islands; under RCP8.5, it decreases everywhere in both islands. Heavy precipitation rates should increase, especially in the south-southwestern parts of the Sao Tome islands. Detailed spatial variability of the temperature and precipitation changes in the islands can only be revealed at very high spatial model resolution. Implications for the potential energy production from two major river basins are assessed in this work. 相似文献
20.
Roger Rodrigues Torres Jose Antonio Marengo 《Theoretical and Applied Climatology》2014,117(3-4):579-587
This study identifies possible hotspots of climate change in South America through an examination of the spatial pattern of the Regional Climate Change Index (RCCI) over the region by the end of the twenty-first century. The RCCI is a qualitative index that can synthesize a large number of climate model projections, and it is suitable for identifying those regions where climate change could be more pronounced in a warmer climate. The reliability and uncertainties of the results are evaluated by using numerous state-of-the-art general circulation models (GCMs) and forcing scenarios from the Coupled Model Intercomparison Project phases 3 and 5. The results show that southern Amazonia and the central-western region and western portion of Minas Gerais state in Brazil are persistent climate change hotspots through different forcing scenarios and GCM datasets. In general, as the scenarios vary from low- to high-level forcing, the area of high values of RCCI increase and the magnitude intensify from central-western and southeast Brazil to northwest South America. In general, the climatic hotspots identified in this study are characterized by an increase of mean surface air temperature, mainly in the austral winter; by an increase of interannual temperature variability, predominantly in the austral summer; and by a change in the mean and interannual variability of precipitation during the austral winter. 相似文献