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1.
利用区域气候模式RegCM3以及考虑作物生长过程的耦合模式RegCM3_CERES对东亚区域进行20年模拟,研究作物生长对流域水文过程与区域气候的影响。结果表明：考虑作物生长过程的耦合模式模拟海河流域、松花江流域、珠江流域多年平均降水效果明显改进,在除黑河流域外的各流域模拟的温度负偏差有所减小,其中在海河流域、淮河流域的夏季改进尤为明显。各流域夏季（6、7、8月）月蒸散量最高,其中长江流域、海河流域、淮河流域、珠江流域的夏季月蒸散量基本上在100 mm左右,并且七大流域蒸散发的季节变化趋势跟总降水基本一致。多数流域考虑作物生长过程的耦合模式模拟得出蒸散发减少且进入的水汽增加,导致局地水循环率减小;黑河流域与黄河流域降水有所增加,其他流域均有不同程度的减小。针对长江流域,比较耦合模式RegCM3_CERES与模式RegCM3模拟结果显示,叶面积指数减少1.20 m2/m2,根区土壤湿度增加0.01 m3/m3,进而导致潜热通量下降1.34 W/m2（其中在四川盆地地区减少16.00 W/m2左右）,感热通量增加2.04 W/m2,从而影响到降水和气温。 相似文献
2.
An ensemble of six 22-year numerical experiments was conducted to evaluate the ability of Regional Climate Model version 3 (RegCM3) to simulate the energy and water budgets of the midwestern United States. RegCM3 was run using two surface physics schemes: Integrated Biosphere Simulator (IBIS) and Biosphere-Atmosphere Transfer Scheme 1e (BATS1e), and two convective closure assumptions: Fritsch & Chappell (FC80) and Arakawa & Schubert (AS74). Boundary conditions were provided by the National Centers for Environmental Prediction-Department of Energy Reanalysis 2 dataset and the ECHAM5 general circulation model. A companion paper examines the American Midwest under future climate scenarios. Overall, the model that reproduces the observed seasonal cycles of the midwestern United States climate system best is RegCM3 using IBIS and the AS74 convective closure assumption. IBIS simulates shortwave radiation more accurately, while BATS1e simulates longwave radiation more accurately. Summer two-meter air temperature is overestimated by the combination of IBIS and the FC80 convective closure assumption. All models contain a wet bias and overestimate evapotranspiration during the spring. Total runoff, surface runoff, groundwater runoff, and root zone soil moisture are best simulated by RegCM3 using IBIS and the AS74 convective closure assumption. While BATS1e does capture the seasonal cycle of total runoff, gross errors in the partitioning of total runoff between surface runoff and groundwater runoff exist. The seasonal cycle of root zone soil moisture simulated by RegCM3 using IBIS and the AS74 convective closure assumption is dry, but agrees with observations during the summer. The rest of the models underestimate root zone soil moisture. 相似文献
3.
陆面过程模型CoLM与区域气候模式RegCM3的耦合及初步评估 总被引：6，自引：2，他引：4
陆面过程通过影响陆面和大气之间物质（如,水分）和能量的交换影响气候, 其参数化方案对数值天气预报、全球及区域气候模拟有重要影响。本研究利用对生物物理、生物化学过程考虑更全面的陆面模式Common Land Model(CoLM) 替代区域气候模式RegCM3原有的陆面模式BATS, 发展了耦合区域气候模式C－RegCM3; 将其应用于东亚地区典型洪涝年份夏季气候模拟以进行评估, 结果表明新耦合的模式C－RegCM3能合理模拟大尺度环流场、近地表气温和降水的分布特征, 对西北半干旱地区降水模拟比RegCM3有所改进。通过利用区域气候模式C－RegCM3及RegCM3对地表能量和水文过程模拟结果的比较, 发现在半干旱、半湿润过渡区C－RegCM3模拟的潜热增大、感热减小; 模拟的地表吸收太阳辐射差异较明显的地区位于模式模拟的主要雨区; C-RegCM3在上述过渡区模拟的夏季地表土壤湿度比RegCM3偏干, 这与它在过渡区降水模拟偏少、蒸散发模拟偏大相对应, 体现了该模式在半干旱、半湿润过渡带模拟出比RegCM3更明显的局地土壤湿度－降水－蒸散发之间的正反馈作用。 相似文献
4.
A. L. Steiner J. S. Pal F. Giorgi R. E. Dickinson W. L. Chameides 《Theoretical and Applied Climatology》2005,82(3-4):225-243
Summary We replace the existing land surface parameterization scheme, the Biosphere-Atmosphere Transfer Scheme (BATS), in a regional climate model (RegCM) with the newly developed Common Land Model (CLM0). The main improvements of CLM0 include a detailed 10-layer soil model, the distinction between soil ice and water phases, a linked photosynthesis-stomatal conductance model, a multilayer snow model, and an improved runoff parameterization. We compare the performance of CLM0 and BATS as coupled to the RegCM in a one year simulation over East Asia. We find that the RegCM/CLM0 improves the winter cold bias present in the RegCM/BATS simulation. With respect to the surface energy balance, lower CLM0 albedos allow the absorption of more solar radiation at the surface. CLM0 tends to simulate higher sensible heat and lower latent heat fluxes than its BATS counterpart. The surface water balance also changes considerably between the two land surface schemes. Compared to BATS, CLM0 precipitation is reduced overall and surface runoff is increased, thereby allowing less water to enter the soil column. Evapotranspiration is lower in CLM0 due to lower ground evaporation, which leads to a wetter surface soil in CLM0 in spite of less precipitation input. However, transpiration is greater in CLM0 than BATS, which has an overall effect of less surface storage during the summertime. Comparison with station observations indicates that CLM0 tends to improve the simulation of root zone soil water content compared to BATS. Another pronounced difference between the two schemes is that CLM0 produces lower snow amounts than BATS because of different snow models and warmer CLM0 temperatures. In this case, BATS snow cover amounts are more in line with observations. Overall, except for the snow amounts, CLM0 appears to improve the RegCM simulation of the surface energy and water budgets compared to BATS. 相似文献
5.
Marta Llopart Erika Coppola Filippo Giorgi Rosmeri P. da Rocha Santiago V. Cuadra 《Climatic change》2014,125(1):111-125
We analyze the local and remote impacts of climate change on the hydroclimate of the Amazon and La Plata basins of South America (SA) in an ensemble of four 21st century projections (1970–2100, RCP8.5 scenario) with the regional climate model RegCM4 driven by the HadGEM, GFDL and MPI global climate models (GCMs) over the SA CORDEX domain. Two RegCM4 configurations are used, one employing the CLM land surface and the Emanuel convective schemes, and one using the BATS land surface and Grell (over land) convection schemes. First, we find considerable sensitivity of the precipitation change signal to both the driving GCM and the RegCM4 physics schemes (with the latter even greater than the first), highlighting the pronounced uncertainty of regional projections over the region. However, some improvements in the simulation of the annual cycle of precipitation over the Amazon and La Plata basins is found when using RegCM4, and some consistent change signals across the experiments are found. One is a tendency towards an extension of the dry season over central SA deriving from a late onset and an early retreat of the SA monsoon. The second is a dipolar response consisting of reduced precipitation over the broad Amazon and Central Brazil region and increased precipitation over the La Plata basin and central Argentina. An analysis of the relative influence on the change signal of local soil-moisture feedbacks and remote effects of Sea Surface Temperature (SST) over the Niño 3.4 region indicates that the former is prevalent over the Amazon basin while the latter dominates over the La Plata Basin. Also, the soil moisture feedback has a larger role in RegCM4 than in the GCMs. 相似文献
6.
利用区域气候模式Reg CM4.3(Regional Climate Mode version 4.3)对新疆地区冬季的地表状态进行了模拟分析,通过与ERA40再分析资料的对比分析发现,温度分布形势模拟较好,地面热力状态受地形影响显著,陡峭地形附近由于热性质差异大和非均匀性强会导致较大模拟误差;模式较好模拟出降水和潜热通量北疆多南疆少,山区多盆地少的分布特征,模拟出通过反照率影响,地表吸收的短波辐射呈现出沙漠腹地吸收多而天山地区吸收少的分布,对北疆呈感热通量汇而南疆呈感热通量源的感热分布形势也模拟较好;模拟的雪水当量与降水分布有较好的一致性,春季融雪径流与冬季雪水当量分布及降水均有较好的对应关系。通过模拟分析也发现,现有方案实际感热通量计算中以地面温度代替地面位温,造成感热通量偏小,因此会低估南疆感热源效应和高估北疆感热汇效应。此外,积雪量和地面温度模拟偏高可能是春季北疆主要积雪区径流偏强的原因。 相似文献
7.
以高寒山区—黑河流域上游为研究区，确定区域气候模式RegCM3的模拟方案，率定分布式水文模型（DLBRM），并开发了RegCM3和DLBRM模型接口，从而构建了区域气候水文耦合模拟系统CRCHMS。结果表明，以RegCM3作为气象驱动数据的CRCHMS系统模拟性能优于以观测站点作为气象驱动数据的DLBRM模型，对莺落峡径流量的模拟值与实测值的相关系数在校准期和验证期分别为0.47和0.62，均方根误差分别为0.045和0.044 cm/d，相对误差分别为-0.4%和6%，纳什系数在率定期和验证期分别为0.22和0.36。 相似文献
8.
黄淮海地区是我国传统的农耕区,也是经济快速发展、城镇化进程快速推进的区域之一,使得该地区植被覆盖发生了明显变化。为研究城镇化对气候与水资源的影响,应用RegCM3区域气候模式,通过控制试验和敏感性试验,在保证积分时间（2001-2005年）的情况下,输出降水、蒸发、温度、湿度、土壤水分、径流、整层水汽含量等资料,利用敏感性试验和控制试验输出量的差值,来分析黄淮海地区城镇化对气候和水资源要素的影响情况。结果表明,城镇化对研究地区气候及水资源造成的影响主要表现在使局地风场减弱、降水减少、地面气温增加、空气湿度减小、水资源总量减少、土壤含水量减少和地表径流增加等方面,从而对气候和水资源造成影响。 相似文献
9.
Climate�Csoil�Cvegetation control on groundwater table dynamics and its feedbacks in a climate model
Among the three dynamically linked branches of the water cycle, including atmospheric, surface, and subsurface water, groundwater is the largest reservoir and an active component of the hydrologic system. Because of the inherent slow response time, groundwater may be particularly relevant for long time-scale processes such as multi-years or decadal droughts. This study uses regional climate simulations with and without surface water?Cgroundwater interactions for the conterminous US to assess the influence of climate, soil, and vegetation on groundwater table dynamics, and its potential feedbacks to regional climate. Analyses show that precipitation has a dominant influence on the spatial and temporal variations of groundwater table depth (GWT). The simulated GWT is found to decrease sharply with increasing precipitation. Our simulation also shows some distinct spatial variations that are related to soil porosity and hydraulic conductivity. Vegetation properties such as minimum stomatal resistance, and root depth and fraction are also found to play an important role in controlling the groundwater table. Comparing two simulations with and without groundwater table dynamics, we find that groundwater table dynamics mainly influences the partitioning of soil water between the surface (0?C0.5?m) and subsurface (0.5?C5?m) rather than total soil moisture. In most areas, groundwater table dynamics increases surface soil moisture at the expense of the subsurface, except in regions with very shallow groundwater table. The change in soil water partitioning between the surface and subsurface is found to strongly correlate with the partitioning of surface sensible and latent heat fluxes. The evaporative fraction (EF) is generally higher during summer when groundwater table dynamics is included. This is accompanied by increased cloudiness, reduced diurnal temperature range, cooler surface temperature, and increased cloud top height. Although both convective and non-convective precipitation are enhanced, the higher EF changes the partitioning to favor more non-convective precipitation, but this result could be sensitive to the convective parameterization used. Compared to simulations without groundwater table dynamics, the dry bias in the summer precipitation is slightly reduced over the central and eastern US Groundwater table dynamics can provide important feedbacks to atmospheric processes, and these feedbacks are stronger in regions with deeper groundwater table, because the interactions between surface and subsurface are weak when the groundwater table is deep. This increases the sensitivity of surface soil moisture to precipitation anomalies, and therefore enhances land surface feedbacks to the atmosphere through changes in soil moisture and evaporative fraction. By altering the groundwater table depth, land use change and groundwater withdrawal can alter land surface response and feedback to the climate system. 相似文献
10.
土地利用变化对长江流域气候及水文过程影响的敏感性研究 总被引：6，自引：0，他引：6
使用区域气候模式(RegCM3)和大尺度汇流模型(LRM), 研究土地利用/植被覆盖变化对长江流域气候及水文过程的影响。RegCM3嵌套于欧洲数值预报中心 (ECMWF) 再分析资料ERA40, 分别进行了中国区域在实际植被和理想植被分布情况下两个各15年 (1987～2001年) 时间长度的积分试验。随后, RegCM3 两个试验的输出径流结果分别用来驱动LRM, 研究土地利用/植被覆盖变化对长江流域河川径流的影响。研究结果指出, 中国当代土地利用变化对长江流域降水、蒸散发、径流深及河川径流等水文气候要素的改变较大, 对气温的改变并不明显。土地利用变化引起长江干流河川径流量在夏季(6～8月)有所增加, 并且越向下游增加幅度越大, 其中大通站径流量增加接近15%。总体而言, 土地利用改变加剧了长江流域夏季水循环过程, 使得夏季长江中下游地区降水增多, 径流增大。 相似文献
11.
An ensemble of six 22-year numerical experiments was conducted to quantify the response of soil moisture to multiple climate change scenarios over the American Midwest. Regional Climate Model version 3 (RegCM3) was run using two surface physics schemes: Integrated Biosphere Simulator (IBIS) and Biosphere-Atmosphere Transfer Scheme 1e (BATS1e); and two convective closure assumptions: Fritsch and Chappell and Arakawa and Schubert. Experiments were forced with a surrogate climate change scenario constructed using the National Centers for Environmental Prediction-Department of Energy Reanalysis 2 dataset and the ECHAM5 A1B climate change scenario. RegCM3-IBIS and RegCM3-BATS1e simulate increased two-meter air temperature and downward longwave radiation throughout the year under both climate change scenarios. While differences in shortwave radiation are relatively small; some model configurations and climate change scenarios produce additional precipitation, evapotranspiration, and total runoff during the spring and summer. Soil moisture is unchanged or increased throughout the growing season as enhanced rainfall offsets greater evaporative demand. Negligible drying in root zone soil moisture is found in all climate change experiments conducted, regardless of surface physics scheme, boundary conditions, or convective closure assumption. 相似文献
12.
青藏高原冬春季积雪异常对中国春夏季降水的影响 总被引：27，自引：3，他引：27
利用1956年12月～1998年12月共42a，青藏高原及其附近地区78个积雪观测站的雪深和我国160站月降水的距平资料，分析了其气候特征，并用SVD方法分析了冬春季积雪异常与春夏季我国降水异常的关系。用区域气候模式RegCM2模拟了青藏高原积雪异常的气候效应并检验了诊断分析的结果。分析表明，雪深异常，尤其是冬季雪深异常是影响中国降水的一个因子。研究证明，高原冬季雪深异常对后期中国区域降水的影响比春季雪深异常的影响更为重要。数值模拟的结果表明，高原雪深和雪盖的正异常推迟了东亚夏季风的爆发日期，减弱了季风强度，造成华南和华北降水减少，而长江和淮河流域降水增加。冬季雪深异常比冬季雪盖异常和春季雪深异常对降水的影响更为显著。机理分析指出，高原及其邻近地区的积雪异常首先通过融雪改变土壤湿度和地表温度，从而改变了地面到大气的热量、水汽和辐射通量。由此所引起的大气环流变化又反过来影响下垫面的特征和通量输送。在湿土壤和大气之间，这样一种长时间的相互作用是造成后期气候变化的关键过程。与干土壤和大气的相互作用过程有本质差别。 相似文献
13.
14.
We evaluate water budget components—namely, soil moisture, runoff, evapotranspiration, and terrestrial water storage (TWS)—simulated by the Noah land surface model with multi-parameterization options (Noah-MP) in China, a large geographic domain challenging for hydrological modeling due to poor observational data and a lack of one single parameterization that can fit for complex hydrological processes. By comparing the model simulations with multi-source reference data, we show that Noah-MP can generally reproduce the overall spatiotemporal patterns of runoff and evapotranspiration over six major river basins, with the annual correlation coefficients generally greater than 0.8 and the Nash–Sutcliffe model efficiency coefficient exceeding 0.5. Among the six basins evaluated, the best model performance is seen over the Huaihe River basin. The temporal trend of the modeled TWS anomalies agrees well with GRACE (Gravity Recovery and Climate Experiment) observations, capturing major flood and drought events in different basins. Experiments with 12 selected physical parameterization options show that the runoff parameterization has a stronger impact on the simulated soil moisture–runoff–evapotranspiration relationships than the soil moisture factor for stomatal resistance schemes, a result consistent with previous studies. Overall, Noah-MP driven by GLDAS forcing simulates the hydrological variables well, except for the Songliao basin in northeastern China, likely because this is a transitional region with extensive freeze–thaw activity, while representations of human activities may also help improve the model performance. 相似文献
15.
Effects of crop growth and development on regional climate: a case study over East Asian monsoon area 总被引：1，自引：0，他引：1
In this study, the CERES phenological growth and development functions were implemented into the regional climate model, RegCM3 to give a model denoted as RegCM3_CERES. This model was used to represent interactions between regional climate and crop growth processes. The effects of crop growth and development processes on regional climate were then studied based on two 20-year simulations over the East Asian monsoon area conducted using the original regional climate model RegCM3, and the coupled RegCM3_CERES model. The numerical experiments revealed that incorporating the crop growth and development processes into the regional climate model reduced the root mean squared error of the simulated precipitation by 2.2–10.7% over north China, and the simulated temperature by 5.5–30.9% over the monsoon region in eastern China. Comparison of the simulated results obtained using RegCM3_CERES and RegCM3 showed that the most significant changes associated with crop modeling were the changes in leaf area index which in turn modify the aspects of surface energy and water partitions and lead to moderate changes in surface temperature and, to some extent, rainfall. Further analysis revealed that a robust representation of seasonal changes in plant growth and developmental processes in the regional climate model changed the surface heat and moisture fluxes by modifying the vegetation characteristics, and that these differences in simulated surface fluxes resulted in different structures of the boundary layer and ultimately affected the convection. The variations in leaf area index and fractional vegetation cover changed the distribution of evapotranspiration and heat fluxes, which could potentially lead to anomalies in geopotential height, and consequently influenced the overlying atmospheric circulation. These changes would result in redistribution of the water and energy through advection. Nevertheless, there are significant uncertainties in modeling how monsoon dynamics responds to crop modeling and more research is needed. 相似文献
16.
In this research the dynamic downscaling method by Regional Climate Model (RegCM4.5) was used to assess the performance and sensitivity of seasonal simulated North and West of Iran (NI&WI) climate factors to different convection schemes, and transforms the large-scale simulated climate variables into land surface states over the North of Iran (NI) and West of Iran (WI). A 30-year (1986–2015) numerical integration simulation of climate over NI&WI was conducted using the regional climate model RegCM4.5 nested in one-way ERA-Interim reanalysis data. The Grell, Kuo and MIT-Emanuel cumulus convection with Holtslag and University of Washington (UW) planetary boundary layer (PBL) parameterization schemes were applied in the running of RegCM4.5 to test their capability in simulating precipitation and temperature in winter-spring (January–April) over NI and WI. The results demonstrated that the RegCM4.5 model has a good potential for simulating the variables and trend of surface temperature over the NI and WI region. Magnitude of the model bias for land surface temperature over different regions of Iran varies by convection parameterization schemes. In most cases, the root mean square error between post-processed simulated seasonal average temperature and observation value was less than 1 °C, but there is a systematic “cold bias”. In general, with respect to land surface temperature simulations, a better performance is obtained when using post-processing model’s data with Holtslag PBL-Grell and Holtslag PBL-Kuo configuration schemes, compared to the other simulations, over the NI&WI region. Also, the UW PBL convection schemes show a relatively excellent spatial correlations and normalized standard deviations closer to 1 for thirty-year seasonal land surface temperature anomalies over the entire NI&WI region. However, the simulation accuracy of model for precipitation is not as optimal as for temperature. The dominant feature in model simulations is a dry bias with the largest average value (∼1.04 mm/day) over NI region, while the lowest mean bias precipitation (∼−0.47 mm/day), mainly located in WI region. In the comparison of six configuration convection schemes, the Emanuel scheme has been proven to be the most accurate for simulating winter-spring seasonal mean precipitation over NI&WI region. The accuracy of the scheme also showed great difference in simulated station interpolation of precipitation, which urges the improvement for the simulation capability of spatial distribution of precipitation. In general, for seasonal variation of precipitation, the Emanuel convection with two (Holtslag, UW) PBL configuration schemes outperforms with a good correlation score between 0.7−0.8 and normalized standard deviations closer to 1. 相似文献
17.
中国当代土地利用变化对黄河流域径流影响 总被引：5，自引：1，他引：4
使用区域气候模式(RegCM3)和大尺度汇流模型(LRM),研究中国地区土地利用/植被覆盖变化对黄河流域降雨径流过程的影响。RegCM3嵌套于欧洲数值预报中心(ECMWF)再分析资料ERA40,分别进行了中国区域在实际植被和理想植被分布情况下两个各15年(1987～2001年)时间长度的积分试验。随后,RegCM3 两个试验的输出径流结果分别用来驱动LRM。与观测资料的对比分析表明,在实际土地利用状况下,LRM能较好地模拟黄河河川径流的季节和年际变化。研究结果指出,当代土地利用引起了冬季黄河上游部分地区降水减少,中下游地区降水增加;引起夏季整个黄河流域降水的减少。总体来说,当代土地利用变化引起黄河流域年平均降水的减少。对于水文站河川径流量,除了冬春季略有增加外,其他月份河川径流均会减少,并且在9月减少最多。土地利用引起的植被退化造成黄河径流的大幅度减少,并且越向下游减少幅度越大,这可能是引起黄河下游断流的重要原因之一。 相似文献
18.
Effects of subgrid heterogeneities in soil infiltration capacity and precipitation on regional climate: a sensitivity study 总被引：7，自引：0，他引：7
X.-M. Zeng M. Zhao B.-K. Su J.-P. Tang Y.-Q. Zheng Y.-J. Zhang J. Chen 《Theoretical and Applied Climatology》2002,73(3-4):207-221
Summary ?One of the most pronounced features of the land surface is its heterogeneity. In order to further understand land-atmosphere
interactions and improve climate modeling it is very important to investigate effects of subgrid scale heterogeneities, especially
hydrological-process heterogeneities. In this paper, after the construction and sensitivity tests of a hydrological model
(VXM), which accounts for precipitation heterogeneity (PH) and infiltration heterogeneity (IH), we incorporated VXM into the
NCAR (National Center for Atmospheric Research) regional climate model RegCM2 and thus obtained the augmented regional climate
model (hereafter, ARCM). By using 3-month (May–July) observational data of 1991 Meiyu season, we conducted numerical experiments
with ARCM, analyzed the sensitivities, and found that: (1) The regional climate and surface hydrology are very sensitive to
IH as well as PH, i.e., the simulations for the surface fluxes, soil temperature, soil moisture, precipitation and surface
runoff can be greatly affected by those heterogeneities. (2) ARCM can effectively improve the simulation of hydrological processes,
i.e., it can greatly enhance the surface runoff ratio (i.e., the ratio of surface runoff to precipitation), which is consistent
with observations over humid areas in China. (3) It seems that the IH influence on the surface climate is larger than the
PH influence. (4) The modeled climate is sensitive to the VXM parameters. For example, it is significantly modified after
the surface impermeable fraction has been accounted for, suggesting some features of aridification.
Received June 18, 2001; revised February 14, 2002; accepted March 3, 2002 相似文献
19.
气候变化和人类活动对中国东部季风区水循环影响的检测和归因 总被引：2，自引：0，他引：2
水文循环过程受气候变化与人类活动的共同作用,区分气候内部自然变率与人类活动作用于水循环贡献对于增加气候变化的理解非常重要。本研究利用近期发展的考虑地下水取用水与灌溉影响的全球陆气耦合模式进行数值模拟,基于最优指纹法分析探讨中国东部季风区黄河、淮河、海河、珠江、长江、松花江流域水循环变化(地表温度、降水、径流、蒸散发)及归因。结果表明:大部分流域的地表温度年际变化在1965~2005年间检测到包括温室气体气溶胶人为排放、臭氧与土地利用变化产生的外强迫效应,显示在长期对于地表温度起主要作用的可能为上述强迫;1965~2005年降水年际变化仅在淮河及长江下游检测到上述强迫效应,且在长江下游效应占主导。在1965~1984年间,地表温度的年际变化在海河流域检测到由于地下水取水灌溉产生的外强迫效应,并且该效应占主导。在1982~2005年径流年际变化中,在淮河、长江下游及黄河下游处检测到了由于温室气体排放、气溶胶人为排放、臭氧变化及土地利用变化等产生的外强迫效应但无法有效分离,显示该信号在这些地区可能不为主导效应;1982~2005年间的蒸散发年际变化在珠江、长江下游同样检测到了上述强迫效应,并且该效应在长江下游占主导效应。 相似文献
20.
A 20-year simulation of regional climate over East Asia by the regional climate model RegCM3_CERES (Regional Climate Model version 3 coupled with the Crop Estimation through Resource and Environment Synthesis) was carried out and compared with observations and the original RegCM3 model to comprehensively evaluate its performance in simulating the regional climate over continental China. The results showed that RegCM3_CERES reproduced the regional climate at a resolution of 60 km over China by using ERA40 data as the boundary conditions, albeit with some limitations. The model captured the basic characteristics of the East Asian circulation, the spatial distribution of mean precipitation and temperature, and the daily characteristics of precipitation and temperature. However, it underestimated both the intensity of the monsoon in the monsoonal area and precipitation in southern China, overestimated precipitation in northern China, and produced a systematic cold temperature bias over most of continental China. Despite these limitations, it was concluded that the RegCM3_CERES model is able to simulate the regional climate over continental China reasonably well. 相似文献