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模拟温室效应对我国气候变化的影响 总被引：22，自引：0，他引：22
利用5个全球大气海洋海冰模式,模拟了大气中二氧化碳浓度的增加对我国冬季与夏季地面气温、降水率及土壤湿度的影响。结果表明,由于温室效应,我国冬、夏季气温增暖,降水率与土壤湿度也有明显变化。 相似文献
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本文利用全球三维大气耦合混合层海洋环流模式模拟大气中二氧化碳浓度增加对土壤湿度的影响。敏感试验(2×CO_2)与控制试验(1×CO_2)对照表明,当大气中二氧化碳浓度增加时,全球土壤湿度在各季发生明显变化。其中两半球低纬度地区在冬季土壤温度变温,两半球中纬度地区则在各季土壤湿度变干,北半球高纬度地区土壤湿度在夏季变干,其余各季变温。分析大气中二氧化碳浓度增加造成土壤温度全球变化的可能物理机制表明,地面水循环和热量循环是重要的因素。 相似文献
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用IAP/LASG GOALS模式模拟CO_2增加引起的东亚地区气候变化(英文) 总被引：9，自引：0，他引：9
用一个全球耦合的海洋──大气──陆地系统模式（ＩＡＰ／ ＬＡＳＧ ＧＯＡＬＳ）研究因 ＣＯ２增加引起的全球增暖,重点是讨论东亚地区气候变化。完成了两个试验,一个是ＣＯ２含量保持不变的对照试验,一个是ＣＯ２浓度按每年１０％增加的扰动试验。结果表明,在对照试验中没有出现气候漂移,在ＣＯ２含量加倍时全球平均地面气温将增加１．６５℃。ＧＯＡＬＳ模式能较好模拟观测的东亚温度和降水的空间分体和年循环,但模拟的年平均温度略偏低、年降水稍偏大。在ＣＯ２含量加倍时,东亚地区温度和降水将分别增加２．１℃和５％,最大增温出现在中纬度大陆上,最大的降水增加出现在２５°Ｎ附近。 相似文献
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利用CAM3.0气候模式模拟研究东亚地区气溶胶浓度增长以及1976/1977年前后发生的海温年代际变化对东亚夏季降水场的影响及其机制。采用四组试验:即对东亚区域(100~150 °E,20~50 °N)分别进行的单独加倍黑碳气溶胶浓度、单独加倍硫酸盐气溶胶浓度、同时加倍这两种气溶胶浓度的三组关于气溶胶直接气候效应的试验及全球海温在1976/1977前后发生变化的海温年代际变化试验,来比较、探讨海温年代际变化和东亚地区气溶胶浓度增加对东亚夏季降水的影响机制。结果表明,无论是海温年代际变化还是各种气溶胶的浓度加倍,都能导致我国出现长江以北地区降水减少-东南沿海地区降水增加的“南涝北旱”的降水异常分布型。但两者在洋面上空降水的迥异表现及东亚低层风场的不同变化,显示其具有不同的异常降水机制。比较三类气溶胶浓度增加的试验结果发现:在单独硫酸盐气溶胶浓度增加试验中,东亚中部出现最显著的中下层大气降温、异常下沉气流以及降水减少;而在黑碳气溶胶试验中,出现在东亚中部的异常下沉气流强度减弱且位置偏南;在同时增加两类气溶胶浓度时,降水异常分布与单独黑碳气溶胶浓度增加所导致的降水异常相近,但强度减小。 相似文献
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土壤湿度初始异常对东亚区域气候模拟影响的敏感性试验 总被引：1，自引：0，他引：1
利用耦合了CLM3.5陆面模式的区域气候模式RegCM4.0,通过敏感性试验,探讨了人为减小春季初始土壤体积水含量对短期时间尺度东亚夏季气候模拟的可能影响。结果表明:较低的初始土壤湿度场能够明显改变区域的地表能量平衡,引起地表净长波辐射和感热通量的显著增加,进而加强了地表对大气的加热,因而引起东亚大范围地区特别是中国东部、印度北部和中亚地区地表温度、气温的升高。与气温不同,初始土壤湿度场对降水的影响很小而且有较大的不确定性,同时偏暖的下垫面使得对流层中高层出现暖高压异常,但这些影响均不显著。综合来看,土壤湿度初始场的初始异常,对RegCM4.0 模式东亚气候模拟的结果有一定影响,特别是在地表温度、气温和能量平衡方面,应在以后的模拟中加以考虑。 相似文献
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五个全球大气海洋环流模式模拟二氧化碳增加对气候变化的影响 总被引：15，自引：0，他引：15
本文总结五个应用较广的全球大气与海洋环流模式(GFDL,GISS,NCAR,OSU与UKMO),模拟由于人类活动造成大气中二氧化碳浓度增加对气候变化的影响模拟表明,由于大气中二氧化碳浓度增加,将导致全球地面气温增暖大约4℃,其中高纬与极区冬季增暖更明显。高纬与极区海冰和积雪融化增加。全球降水率与土壤湿度在部分地区明显增加,部分地区明显减少,引人注意的是中纬度地区土壤湿度可能变干燥。 本文还给出发达国家与发展中国家在能源战略的各种考虑下各自相应对大气中二氧化碳浓度的影响,以及展望未来由于人类活动的结果,将对全球大气与海洋温度的变暖和土壤湿度变化的影响。 相似文献
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基于NCAR大气模式CAM3.1模式,设计了有、无土壤湿度年际异常两组试验对中国区域近40a(1961-2000年)气候进行了模拟。从气候态和年际变率的角度,通过分析两组试验的差值场来探讨土壤湿度年际异常对气候模拟的影响,并初步探讨了影响的可能机制。结果表明:模式模拟的温度和降水对土壤湿度的年际异常非常敏感,土壤湿度的年际变化对中国春夏季气候及其年际变率均有显著影响。当不考虑土壤湿度年际异常时,模式模拟的春夏季平均温度、最高温度、最低温度在我国大范围内降低,春夏季降水在东部大部分地区明显减少,西部增加。而模式模拟的春夏季温度、降水年际变率在中国大部分地区减弱。但当考虑土壤湿度的年际变化,则能在一定程度上提高模式对气候年际变率的模拟能力。在进一步分析表明土壤湿度年际异常时,主要通过改变地表能量通量和环流场,对温度、降水产生影响。当不考虑土壤湿度年际异常时,地表净辐射通量减少,地表温度降低,感热通量减少。感热通量差值场的空间变化和温度差值场的空间变化一致,感热通量对温度有一定影响。而潜热通量差值场的空间变化和降水的差值场的空间变化一致,可见降水受地表潜热通量的影响。土壤湿度年际异常引起的环流场的变化也是导致气候变化的原因之一,地表能量和环流场年际变率的改变对春夏季气候年际变率存在一定影响。 相似文献
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温湿变化的年代际特征及区域差异是全球气候变化研究的重要内容之一。利用1901-2014年东英吉利大学气候研究中心(CRU)TS3.20月地表温度和降水资料分析了东亚和北美地区温度和降水变化的季节性和区域特征,并利用1979-2015年欧洲中心天气预报中心(ECMWF)ERA-Interim日最高/最低温和降水资料进一步分析了东亚和北美地区受极端天气影响的区域所占比例的年际变化。结果发现,近110多年来东亚地区[0.134℃·(10a)~(-1)]的增温趋势高于北美地区[0.102℃·(10a)~(-1)],东亚干旱半干旱区的增温趋势低于东亚地区,而北美干旱半干旱区的增温趋势高于北美地区。季节性特征表现为在冷季增温明显,东亚地区冷季增温约是暖季的2.9倍,北美地区为1.3倍。季节性增温存在明显的纬度差异,在东亚和北美高纬度地区(45°N以北)冷季温度的增长速率通常比暖季大。东亚和北美的降水增加趋势均高于北半球,暖季降水增加明显并且主要发生在东亚和北美高纬度地区(45°N以北)。东亚和北美的干旱半干旱区的降水没有明显增加趋势,分别为0.04 mm·(10a)~(-1)和0.07 mm·(10a)~(-1)。东亚和北美地区及东亚和北美的干旱半干旱区受极端高温影响的面积有增加趋势,受极端低温影响的面积没有明显变化,受极端降水影响的面积有减少趋势。北美和东亚地区以及北美和东亚干旱半干旱区的月平均温度对PDO(Pacific Decadal Oscillation)的响应比ENSO(El Nino Southern Oscillation)明显,月平均降水对ENSO的响应比PDO明显。 相似文献
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基于气温和降水观测资料以及美国国家环境预报中心/国家大气研究中心（NCEP/NCAR）大气再分析资料,系统评估了大样本初始化十年际预测试验（CESM-DPLE）对1959—2016年东亚夏季气候预测的能力。结果表明,CESM-DPLE能较好地模拟东亚夏季气候以及相关主要大气环流系统的基本态特征,在年际尺度上对东亚气温有很高的预测技巧但对降水几乎没有预测能力。CESM-DPLE再现了北大西洋多年代际振荡（AMO）经由激发遥相关波列所引起的中高纬度大气环流、东亚夏季风和气候的异常。20世纪90年代末之后,北大西洋多年代际振荡由冷位相转为暖位相,遥相关波列位相调整,东亚受异常低压控制,东亚夏季风偏强,夏季气温偏高、降水偏多。总体上,尽管还存在着不足,但CESM-DPLE对东亚夏季温度年际变化以及与20世纪90年代末北大西洋多年代际振荡位相转变相联的东亚夏季气候年代际变化具备一定的预测能力,是目前研究和预测东亚气候变化的一套较好试验数据。 相似文献
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Yonghui Yang Masataka Watanabe Zhiping Wang Yasuo Sakura Changyuan Tang 《Climatic change》2003,57(1-2):163-183
The WAVES model was used to simulate the effect of global warming on soil moisture on the semi-arid Taihang Mountain in China. Parameters of the WAVES model were first adjusted according to soil moisture data from a field global warming experiment. Then, the reliability of WAVES in predicting soil moisture changes induced by climatic change was confirmed by comparing the simulated and observed soil moisture values under different climatic conditions and plant growth rates of another field treatment. Next, 10 climate change scenarios incorporating increases in temperature and changes in precipitation were designed. When a simulation was conducted using the leaf area index (LAI) growth pattern from a field experiment under the present climatic conditions, the results suggested that the combination of temperature increase and precipitation decrease would greatly decrease soil water content throughout the entire simulation period. On the other hand, only when precipitation increased by 20% and temperatureincreased by 2 °C, the effect of precipitation increase on soil moisture was obviously positive. Although soil moisture conditions in the T2P1 (temperature increase by 2 °C and precipitation increase by 10%) and T4P2 (temperature increase by 4 °C and precipitation increase by 20%) scenarios were slightly better during the rainy season and notmuch changed before the rainy season, the positive effect of 10%precipitation increase on soil moisture was totally offset by moisture decrease caused bya 4 °C temperature increase in the T4P1 scenario. At the same time, the trends of soil-moisture change were highly coincident with predicted changes in productivity. Finally, the predicted LAI values from other studies were combined with the climatic change scenarios and used in the simulation. The results showed that changes in LAI alleviated, at least to some extent, the effects of temperature and precipitation changes on soil moisture. 相似文献
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青藏高原为全球气候变化中的敏感区域。利用WRF3.5.1中尺度模式,选取青藏高原为关键区域,设计干、湿土壤湿度两组敏感试验,以探讨青藏高原土壤湿度异常对中国夏季短期区域气候产生的可能影响。结果表明：模式模拟的短期区域气候对土壤湿度十分敏感,湿土壤导致东北、内蒙古东北部以及华东地区降水增多,与此同时,全国大部分地区气温下降,且各地区表现较一致;干土壤导致西北、华北、华中以及西南除四川西部以外的地区降水减小,全国气温除华中地区以外,普遍升高。湿土壤对降水主要表现为正反馈作用,对气温表现为负反馈作用。干土壤则反之。 相似文献
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Assessment of future climate change over East Asia due to the RCP scenarios downscaled by GRIMs-RMP 总被引：1，自引：1，他引：0
Ji-Woo Lee Song-You Hong Eun-Chul Chang Myoung-Seok Suh Hyun-Suk Kang 《Climate Dynamics》2014,42(3-4):733-747
This study assesses future climate change over East Asia using the Global/Regional Integrated Model system—Regional Model Program (RMP). The RMP is forced by two types of future climate scenarios produced by the Hadley Center Global Environmental Model version 2 (HG2); the representative concentration pathways (RCP) 4.5 and 8.5 scenarios for the intergovernmental panel on climate change fifth assessment report (AR5). Analyses for the current (1980–2005) climate are performed to evaluate the RMP’s ability to reproduce precipitation and temperature. Two different future (2006–2050) simulations are compared with the current climatology to investigate the climatic change over East Asia centered in Korea. The RMP satisfactorily reproduces the observed seasonal mean and variation of precipitation and temperature. The spatial distribution of the simulated large-scale features and precipitation by the RMP is generally less reflective of current climatic conditions than that is given by the HG2, but their inter-annual variations in East Asia are better captured by the RMP. Furthermore, the RMP shows higher reproducibility of climate extremes including excessive heat wave and precipitation events over South Korea. In the future, strong warming is distinctly coupled with intensified monsoonal precipitation over East Asia. In particular, extreme weather conditions are increased and intensified over South Korea as follows: (1) The frequency of heat wave events with temperature greater than 30 °C is projected to increase by 131 and 111 % in the RCP 8.5 and 4.5 downscaling, relative to the current climate. (2) The RCP 8.5 downscaling shows the frequency and variability of heavy rainfall to increase by 24 and 31.5 %, respectively, while the statistics given by the RCP 4.5 downscaling are similar to those of the current climate. 相似文献
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用 IAP／LASG GOALS模式模拟CO2增加引起的东亚地区气候变化 总被引：19，自引：0，他引：19
Two simulations, one for the control run and another for the perturbation run, with a global coupled ocean-atmosphere-land system model (IAP / LASG GOALS version 4) have been carried out to study the global warming, with much detailed emphasis on East Asia. Results indicate that there is no climate drift in the control run and at the time of CO2 doubling the global temperature increases about 1.65℃. The GOALS model is able to simulate the observed spatial distribution and annual cycles of temperature and precipitation for East Asia quite well. But, in general, the model underestimates temperature and overestimates rainfall amount for regional annual average. For the climate change in East Asia, the temperature and precipitation in East Asia increase 2. l℃ and 5% respectively, and the maximum warming occurs at middle-latitude continent and the maximum precipitation increase occurs around 25°N with reduced precipitation in the tropical western Pacific. 相似文献
15.
Sensitivity of Runoff, Soil Moisture and Reservoir Design to Climate Change in Central Indian River Basins 总被引：2，自引：0，他引：2
R. Mehrotra 《Climatic change》1999,42(4):725-757
Climate change due to a doubling of the carbon dioxide in the atmosphere and its possible impacts on the hydrological cycle are a matter of growing concern. Hydrologists are specifically interested in an assessment of the impacts on the occurrence and magnitude of runoff, evapotranspiration, and soil moisture and their temporal and spatial redistribution. Such impacts become all the more important as they may also affect the water availability in the storage reservoirs. This paper examines the regional effects of climate change on various components of the hydrologic cycle viz., surface runoff, soil moisture, and evapotranspiration for three drainage basins of central India. Plausible hypothetical scenarios of precipitation and temperature changes are used as input in a conceptual rainfall-runoff model. The influences of climate change on flood, drought, and agriculture are highlighted. The response of hypothetical reservoirs in these drainage basins to climate variations has also been studied. Results indicate that the basin located in a comparatively drier region is more sensitive to climatic changes. The high probability of a significant effect of climate change on reservoir storage, especially for drier scenarios, necessitates the need of a further, more critical analysis of these effects. 相似文献
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An assessment of future dryness over Korea based on the ECHAM5-RegCM3 model chain under A1B emission scenario 总被引：2，自引：0，他引：2
Eun-Soon Im Joong-Bae Ahn Do-Woo Kim 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(4):325-337
We analyze the future dryness over Korea based on the projected temperature and precipitation. For fine-scale climate information, the ECHAM5/MPI-OM A1B simulation has been dynamically downscaled using the RegCM3 double-nested system. A 130-year long-term climatology (1971?C2100) from the mother domain (East Asia: 60 km) and nested domain (South Korea: 20 km) is discussed. Based on the intercomparison with CMIP3 participant models, the ECHAM5/MPI-OM provides climatic change information over the East Asia that is not markedly different from other projections. However, the reduction of summer precipitation over Korea is rather different with ensemble mean of CMIP3 participant models. The downscaled results generally follow the behavior of ECHAM5/MPIOM, but substantial fine-scale details are found in the spatial pattern and the change signals become more enhanced at the local scale. In the future projection, significant warming is found regardless of the season and region while the change in precipitation shows a mixed feature with both increasing and decreasing patterns. The increase of temperature enhances the evapotranspiration, and hence the actual water stress becomes more pronounced in the warmer climate. This is related to the negative trends of the self-calibrating Palmer Drought Severity Index (PDSI) to measure the drought condition in Korea. Although PDSI is overall associated with the precipitation variation, its long-term trend tends to be modulated by the temperature trend. It is confirmed that the detrended temperature is shown to mask the decreasing tendency of the PDSI. The result indicates that without an increase in precipitation appropriate for atmospheric moisture demand, future dryness is a more likely condition under global warming. 相似文献
17.
Performance of a regional climate model (RCM), WRF, for downscaling East Asian summer season climate is investigated based on 11-summer integrations associated with different climate conditions with reanalysis data as the lateral boundary conditions. It is found that while the RCM is essentially unable to improve large-scale circulation patterns in the upper troposphere for most years, it is able to simulate better lower-level meridional moisture transport in the East Asian summer monsoon. For precipitation downscaling, the RCM produces more realistic magnitude of the interannual variation in most areas of East Asia than that in the reanalysis. Furthermore, the RCM significantly improves the spatial pattern of summer rainfall over dry inland areas and mountainous areas, such as Mongolia and the Tibetan Plateau. Meanwhile, it reduces the wet bias over southeast China. Over Mongolia, however, the performance of precipitation downscaling strongly depends on the year: the WRF is skillful for normal and wet years, but not for dry years, which suggests that land surface processes play an important role in downscaling ability. Over the dry area of North China, the WRF shows the worst performance. Additional sensitivity experiments testing land effects in downscaling suggest the initial soil moisture condition and representation of land surface processes with different schemes are sources of uncertainty for precipitation downscaling. Correction of initial soil moisture using the climatology dataset from GSWP-2 is a useful approach to robustly reducing wet bias in inland areas as well as to improve spatial distribution of precipitation. Despite the improvement on RCM downscaling, regional analyses reveal that accurate simulation of precipitation over East China, where the precipitation pattern is strongly influenced by the activity of the Meiyu/Baiu rainfall band, is difficult. Since the location of the rainfall band is closely associated with both lower-level meridional moisture transport and upper-level circulation structures, it is necessary to have realistic upper-air circulation patterns in the RCM as well as lower-level moisture transport in order to improve the circulation-associated convective rainfall band in East Asia. 相似文献
18.
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
19.
Simulation of paleoclimate over East Asia at 6 ka BP and 21 ka BP by a regional climate model 总被引：5，自引：0，他引：5
Using a regional climate model with detailed land surface processes (RegCM2), East Asian monsoon climates at 6 ka BP and 21 ka BP are simulated by prescribing vegetation and employing paleovegetation respectively in order to examine land surface effects on East Asian climate system and the potential mechanisms for climate change. The RegCM2 with a 120 × 120 km2 resolution has simulated the enlargement of the seasonal cycle of insolation, the temperature rising the whole year, and the reduction of perpetual snow in high latitudes at 6 ka BP. The simulation shows the East Asian summer monsoon strengthening, precipitation and P–E increasing, and the monsoon rain belt shifting westwards and northwards. Effect of paleovegetation included in the modeling reduced surface albedo and caused an increase in the winter temperature, which led to weakening of the winter continental cold anticyclone over China. The results make the seasonal characteristics of simulated temperature changes in better agreement with the geological records, and are an improvement over previous simulations of Paleoclimate Modeling Intercomparison Project (PMIP). The RegCM2 simulated the 21 ka BP climate with lowered temperature throughout the year, and with precipitation reduced in most areas of East Asia (but increased in both the Tibetan Plateau and Central Asia). Low temperature over East Asia led to the strengthening of the East Asian winter monsoon and the shrinking of the summer monsoon. The effect of paleovegetation included in the experiment has enlarged the glacial climate influence in East Asia, which is closer to geological data than the PMIP simulations directly driven by insolation, glaciation and low CO2 concentration. 相似文献