共查询到17条相似文献，搜索用时 125 毫秒
1.
采用政府间气候变化委员会资料中心的模式预测结果,本文分析了SRES A2温室气体和气溶胶排放情景下中国大陆21世纪前30年的10年际气候变化趋势. 研究揭示：大陆冬季和夏季表面温度、表面最高温度和最低温度分别升高0.3～2.3℃、0.1～2.0℃、0.5～2.7℃,增幅大体上呈现东西向带状分布,由南至北升温逐渐加强,且增幅随时间加大. 此外,上述三气候要素冬季升温幅度要大于同期夏季、表面最低温度升幅要强于同期表面最高温度,冬季和夏季表面温度的季节内变化范围减小. 冬季东亚地区海平面气压异常幅度在-1.0hPa至0.4hPa之间变化,呈东西向带状分布,表现为南正北负、随时间推进异常幅度有所加大,正负交界面向南扩展;同时,东北、华北和西部海平面气压负异常较大. 夏季海平面气压异常空间分布与冬季相似. 2001～2030年,青藏高原大部、大陆东南部和河套大部分地区降水量增加0.1～0.8mm/d. 相似文献
2.
使用全球海气耦合模式和区域气候模式,对人类活动影响导致的温室气体和气溶胶增加引起的长江中下游地区的气候变化进行了分析研究.全球模式部分使用的是IPCC数据分发中心提供的5个模式模拟结果,包括IS92a中未来温室气体增加(GG)以及温室气体和硫化物气溶胶共同增加(GS)和A2、B2共4种排放情景.分析表明在温室气体增加的情况下,这里未来的地面气温变化与全球和全国一样,都呈增加趋势.以GG和GS为例,GG情景下,这一地区的变暖幅度在21世纪末期达到4.2℃, GS情景下达到3.1℃.但总体来说这里的变暖幅度较全球和中国其它大部分地区小.各个季节中,冬春季的增温幅度大于夏秋季.对降水的分析表明,GG情景下长江中下游地区是中国降水增加较少的地区之一,而在GS情景下,降水将出现微弱的减少.区域气候模式的模拟,在气温变化方面得到的结果和全球模式类似.但降水与全球模式的结果有所差别,主要表现在降水增加的季节分布不同上,模拟结果中降水增加最多的是冬季和夏季(增加值分别为44%和23%),而春秋季的降水将减少. 相似文献
3.
本文基于中国科学院大气物理研究所大气科学和地球流体力学国家重点实验室(LASG/IAP)发展的气候系统模式FGOALS_gl对近百年气温变化的模拟,讨论了自然变率和人为因素对20世纪全球变暖的相对贡献.数值试验结果表明,在自然和人为因子的共同强迫作用下,耦合模式能够合理再现20世纪全球平均气温随时间的演变;仅在自然因子作用下,模式不能再现1970年以后的全球变暖.自然因素对20世纪第一次变暖的作用是显著的,但温室气体是20世纪后期变暖的主要原因.在这一定性结论基础上,进一步对近百年变化中自然和人为因素的相对贡献做定量的归因分析,结果表明,除赤道中东太平洋和北大西洋外,人为因素对近百年的增暖起决定性作用.对全球、半球及大陆尺度而言,外强迫可以解释平均气温变化的70%以上,而内部变率贡献较小;但对于区域尺度而言,多数地区内部变率的贡献大于外强迫,区域尺度气温变化的机制较全球、半球尺度要复杂.对中国地区而言,20世纪早期的气温变化受自然变率影响,但20世纪后期的变暖主要是温室气体增加的结果.中国东部气温变化的空间分布表明,自然因素对近50年及近百年中国地区的变暖趋势贡献较小.在自然和人为因子共同作用下,模式能够再现近50年中国东部气温变化冬春两季增暖的特征、但没有模拟出夏季长江中下游地区及淮河流域的降温趋势;自然因子试验的结果表明,太阳活动对该区域的变冷有贡献,但模式无法再现该地区气温的季节变化特征. 相似文献
4.
采用高水平分辨率区域气候模式进行区域未来气候变化预估,对理解全球增暖对区域气候的潜在影响和科学评估区域气候变化有很好的参考价值.这里对国家气候中心使用25 km高水平分辨率区域气候模式RegCM3单向嵌套全球模式MIROC3.2_hires在观测温室气体(1951—2000)和IPCC A1B温室气体排放情景下(2001—2100)进行的共计150年长时间模拟结果,进行华北地区未来气温、降水和极端气候事件变化的分析.模式检验结果表明:模式对当代(1981—2000)气温以及和气温有关的极端气候事件(霜冻日数、生长季长度)的空间分布和数值模拟较好;对降水及和降水有关的极端气候事件(强降水日期、降水强度、五日最大降水量)能够模拟出它们各自的主要空间分布特征,但在模拟数值上存在偏大、偏强的误差.和全球模式驱动场相比,区域模式模拟的气温、降水和极端气候事件有明显的改进.2010—2100年华北地区随时间区域平均气温升高幅度逐渐增大,随之霜冻日数逐渐减少,生长季长度逐渐增多;同时随温室效应的不断加剧,未来降水呈增加的趋势,强降水日期和五日最大降水量逐渐增多、降水强度逐渐增大.从空间分布看,21世纪末期(2081—2100)气温、降水以及有关的极端气候事件变化比21世纪中期(2041—2060)更加明显. 相似文献
5.
人工神经网络模型预测气候变化对博斯腾湖流域径流影响 总被引：9，自引：3，他引：6
温室气体排放量增加造成气候变化,对全球资源环境产生重要影响．本文利用人工神经网络模型建立月降水、气温与径流关系,利用开都河流域降水、气温、径流资料对模型进行训练和验证,通过试算法确定网络模型结构,气温升高和降水量增加对径流影响的敏感程度分析表明,气温升高和降水增加对该区域径流影响较大,且气温升高的影响更为显著,径流增加主要集中在夏季,根据区域气候模型（RCMs）推算的CO2加倍情况下西北地区气候的可能变化,预测位于博斯腾湖流域的开都河大山口站年径流量增加38．6％,其中夏季增加71．8％,冬季增加11．4％。 相似文献
6.
基于CMIP5多模式评估人为和自然因素外强迫在中国区域气候变化中的相对贡献 总被引：1，自引：0，他引：1
《中国科学:地球科学》2016,(2)
基于观测资料和CMIP5多模式的历史试验(考虑所有驱动因子)以及单因子强迫气候归因试验结果,估算了温室气体、气溶胶、土地利用及自然因素等外强迫在中国区域气候变化中的相对贡献.结果表明,人为和自然外强迫的共同作用可解释近30年观测气温变化的95%~99%,其中温室气体引起的温度变化是观测增温的2~3倍,而气溶胶起到了显著的冷却降温作用;人为和自然因素外强迫对近几十年观测降水的变化的可能贡献约为65%~78%,其中,气溶胶和温室气体是中国区域降水的主要外强迫因子,尤其气溶胶主导着中国东部降水变化的分布型,而自然因素外强迫的贡献主要体现在干旱半干旱区.人类活动主导了近60年来中国区域气温的长期非线性趋势,特别是从20世纪60年代开始温室气体的影响强度逐渐增大,是中国区域气候变暖最主要的贡献者;不同外强迫因子对中国区域降水长期非线性趋势的影响具有明显的区域差异,温室气体是20世纪70年代以后干旱半干旱区降水逐渐增加的主要贡献者,而气溶胶的主要影响使湿润半湿润区降水有较为明显下降趋势,土地利用和自然因素外强迫也会造成降水呈减少的趋势.通过最优指纹法(Optimal Fingerprinting)的检测可知,人类活动能够很好地解释近60年来中国区域特别是湿润半湿润区观测气温的变化,其中温室气体的单独作用能够清晰地从观测结果中检测出来;由于多模式结果的不确定性,观测降水变化的归因目前还无法通过残余一致性检测.需要指出的是,尽管本文的研究结果还存在着一定的不确定性,但仍可为中国区域气候变化成因研究及其预测提供科学依据. 相似文献
7.
青藏高原地区气溶胶的时空分布特征及其辐射强迫和气候效应的数值模拟 总被引：7，自引：0，他引：7
利用美国的SAGEⅡ全球月平均格点卫星资料, 对青藏高原地区的大气气溶胶状况进行了分析. 分析表明高原上空平流层大气气溶胶的光学厚度在冬季最大, 春、秋季次之, 夏季最小, 存在明显的季节振荡现象. 然后利用MM 5模拟了气溶胶的辐射强迫状况, 结果表明, 相对于设置均一的背景气溶胶而言, 青藏高原地区的辐射强迫均为正值. 高原上地面土壤温度和地面气温均有所增加, 增加的量级相当, 但增幅略小. 高原上500 hPa处的气温也有所增加, 增幅比地面气温的增幅更小, 但仍处于同一个量级. 相似文献
8.
2006年"碧利斯"台风登陆中国大陆后,在湖南、广东和江西三省交界附近地区造成明显暴雨增幅,造成十分严重的灾害,影响巨大.本文利用高分辨率数值模拟资料,从微观云物理过程角度出发,研究了"碧利斯"暴雨增幅发生前和增幅强降水发生时段云微物理特征的差异,探讨了登陆台风暴雨增幅云微物理方面的可能成因,结果指出:暴雨增幅前后,强降水区云微物理特征存在明显不同,与降水强度的明显增强相伴,云中各种水凝物含量也明显增加,其中云冰、雪和霰等固态水凝物的增加尤为显著,冰相过程对地面降水的贡献明显加大,降水云系发展旺盛、高大;云微物理转化率的对比分析发现,暴雨增幅时段,由水汽凝结过程显著增强所带来的云水的增加,主要通过两个途径作用于暴雨增幅:一是通过云中雨水对云水的碰并收集,促进雨水含量显著增加,进而增强地面降水;二是通过云中雪粒子对云水的碰并造成雪粒子含量增加,增加的雪粒子又被云中霰粒子碰并收集造成霰含量增长,进而由霰粒子融化为雨水,并最终作用于地面降水的增幅.文中最后通过分析总结给出了"碧利斯"暴雨增幅云微物理成因示意图. 相似文献
9.
新疆天山北坡气候变化的生态响应研究 总被引：8，自引：2，他引：8
通过近40年天山北坡气候、水文、现代冰川、湖泊观测数据和近10年卫星遥感数据, 利用遥感和GIS技术, 从地表覆被生态系统和景观尺度, 提出了一套基于遥感的干旱区生态自然变化信息提取的研究方法, 分析了近40年天山北坡气候的变化趋势和与之相应的生态响应关系. 结果表明: (1) 近40年天山北坡气候变化的总体趋势是气温和降水增加, 特别是20世纪90年代以来的近10年气温、降水与径流量增加幅度较大; (2) 近10年天山北坡各地理分区植被综合指数显著提高, 提高幅度较大的是人工绿洲区和前山带, 其变化趋势有利于植被生态的改善; (3) 干旱区植被生态对气候变化的响应非常敏感, 由于近10年天山北坡气候的变化, 其植被覆盖度和生物量持续增加, 平原区增幅明显大于山区, 后期增幅明显大于前期. 相似文献
10.
气候变化对沅江流域径流影响研究 总被引：1，自引：0，他引：1
温室气体排放量增加造成气候变化,对全球资源环境产生重要影响.本文在水量平衡基础上,建立考虑气象要素和地形变化的月水文模型,利用实测径流资料对模型在时空尺度上进行验证.利用全球气候模型(GCMs)预测的未来气候变化情形,对处于湿润区的沅江流域径流过程进行预测.分析结果表明,该区域径流过程对降雨和气温变化十分敏感.根据英国Hadcm2模型对本世纪中叶气候变化预测结果,沅江流域未来年降雨量减少0.43%气温升高1.55℃,丰水期降雨增加,而枯水期将有较大幅度减少.年径流量相应减少6.8%,丰水期径流量增大11%,枯水期径流减少47%,不利于防洪和水资源开发利用. 相似文献
11.
XIAO Dong ZHOU XiuJi & ZHAO Ping Chinese Academy of Meteorological Sciences Beijing China; State 《中国科学:地球科学(英文版)》2012,(9):1504-1517
Despite many studies on reconstructing the climate changes over the last millennium in China,the cause of the China’s climate change remains unclear.We used the UVic Earth System Climate Model(UVic Model),an Earth system model of intermediate complexity,to investigate the contributions of climate forcings(e.g.solar insolation variability,anomalous volcanic aerosols,greenhouse gas,solar orbital change,land cover changes,and anthropogenic sulfate aerosols) to surface air temperature over East China in the past millennium.The simulation of the UVic Model could reproduce the three main characteristic periods(e.g.the Medieval Warm Period(MWP),the Little Ice Age(LIA),and the 20th Century Warming Period(20CWP)) of the northern hemisphere and East China,which were consistent with the corresponding reconstructed air temperatures at century scales.The simulation result reflected that the air temperature anomalies of East China were larger than those of the global air temperature during the MWP and the first half of 20CWP and were lower than those during the LIA.The surface air temperature of East China over the past millennium has been divided into three periods in the MWP,four in the LIA,and one in the 20CWP.The MWP of East China was caused primarily by solar insolation and secondarily by volcanic aerosols.The variation of the LIA was dominated by the individual sizes of the contribution of solar insolation variability,greenhouse gas,and volcano aerosols.Greenhouse gas and volcano aerosols were the main forcings of the third and fourth periods of the LIA,respectively.We examined the nonlinear responses among the natural and anthropogenic forcings in terms of surface air temperature over East China.The nonlinear responses between the solar orbit change and anomalous volcano aerosols and those between the greenhouse gases and land cover change(or anthropogenic sulfate aerosols) all contributed approximately 0.2℃ by the end of 20th century.However,the output of the energy-moisture balance atmospheric model from UVic showed no obvious nonlinear responses between anthropogenic and natural forcings.The nonlinear responses among all the climate forcings(both anthropogenic and natural forcings) contributed to a temperature increase of approximately 0.27℃ at the end of the 20th century,accounting for approximately half of the warming during this period;the remainder was due to the climate forcings themselves. 相似文献
12.
应用CN05观测资料,以及参与国际耦合模式比较计划第5阶段(CMIP5)中的26个模式,评估了新一代全球气候模式对东北三省气候变化模拟能力并选出4个较优模式,发现经过筛选得出的较优模式集合平均模拟结果的可靠性得到进一步加强,尤其体现在对气温的模拟上.在此基础上着重分析了多模式集合在不同典型浓度路径(RCPs)下对未来气候变化特征的预估.结果表明:21世纪的未来阶段,东北三省将处于显著增温的状态,且RCP8.5情景下的增温速率(0.53℃/10a)明显高于RCP4.5情景下的速率(0.22℃/10a);空间上,北部地区将成为增温幅度最大、增温速率最高的区域.未来降水将会相对增加,但波动较大,21世纪末期RCP4.5和RCP8.5情景下的降水增加幅度分别为11.24%和15.95%;空间上,辽宁省西部地区将成为降水增加最为显著的区域.根据水分盈亏量,21世纪未来阶段,RCP4.5情景下的东北三省绝大多数地区未来将相对变湿,尤其到了中后期;RCP8.5情景下则是中西部地区将相对变干,其余地区则会相对变湿. 相似文献
13.
S. G. Dobrovol’skii 《Water Resources》2018,45(4):437-446
A method is proposed for incorporating possible global changes in the state of the atmosphere, basing on K. Hasselmann’s theory of stochastic climate models, for assessing the significance of forecasts of variations of annual river runoff depth in the XXI century. The data used includes the results of river runoff simulation at warming, obtained using 21 IPCC climate models along with six IPCC scenarios of greenhouse gas emission, and MEI scenario. The significance index of forecasted runoff variations, i.e., the values of runoff depth increments divided by the standard error of forecasts was mapped. To demonstrate the role of the maps of significance index, which have been constructed taking into account forecast uncertainty because of the natural changes in global climate, those maps were compared with the maps of significance index calculated basing on other sources of errors. At large time scales, the uncertainty of runoff forecasts owing to natural changes in global climate plays the main role in assessing the reliability of forecasts in areas where greenhouse effect is strongest. Estimates of the significance index show that statistically significant changes in the annual runoff depth in the extreme northeast of Eurasia can be expected to occur not earlier than the late XXI century. In other RF regions, as well as in the majority of world areas, the forecasted changes in the annual runoff depth are comparable with the standard errors of the respective estimates or are less than they are. 相似文献
14.
《水文科学杂志》2013,58(3):596-605
Abstract The potential effect of climatic change on the flow of the Upper Changjiang (or Yangtze River) above the Three Gorges, China, was simulated with the SLURP hydrological model, using ERA40 data from 1961–1990 to simulate the baseline streamflow, and employing scenario temperature and precipitation changes depicted by two global climate models: the Hadley Centre and the Canadian climate model (CCCma) for both the B2 scenario (moderate emission of greenhouse gases) and the A2 scenario (more intense emission), for the 2021–2050 and 2071–2100 time horizons. In general, temperature and precipitation changes are more pronounced for the latter than for the former period. Winter low flows will not change but summer high flow may be augmented by increased precipitation. By mid-century, temperature increase will reduce streamflow according to CCCma, but not so under the Hadley Centre scenario. By the end of the century, precipitation will be great enough to overcome the influence of warming to raise discharge from most parts of the basin. The Min and the Jinsha rivers warrant much attention, the former because of its large flow contribution and the latter because of its sensitivity to climate forcing. 相似文献
15.
Effects of sunspot cycle length and CO2 on air temperature along Qinghai-Xizang railway and air temperature''s trend prediction 总被引：15，自引：0，他引：15
There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73. 相似文献
16.
Evaluating the sensitivity of wetlands to climate change with remote sensing techniques 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Wetlands are valuable ecosystems that provide many valuable services, yet many of these important ecosystems are at risk because of current trends in climate change. The Prairie Pothole Region (PPR) in the upper‐midwest of the United States and south‐central Canada, characterized by glacially sculpted landscapes and abundant wetlands, is one such vulnerable region. According to regional/global climate model predictions, drought occurrence will increase in the PPR region through the 21st century and thus will probably cause the amount of water in wetlands to decline. Water surface area (WSA) of Kidder County, ND, from 1984–2011 was measured by classifying TM/ETM+(Landsat Thematic Mapper / Enhanced Thematic Mapper Plus) images through the modified normalized difference water index. We then developed a linear model based on the WSA of these wetlands and historical climate data and used this to determine the wetland sensitivity to climate change and predict future wetlands WSA in the PPR. Our model based on Palmer drought severity index (PDSI) of the current year (PDSIt ? 0) and of the previous two years (PDSIt ? 2) can explain 79% of the annual wetland WSA variance, suggesting a high sensitivity of wetlands to drought/climate change. We also predicted the PPR wetlands WSA in the 21st century under A1B scenario (a mid‐carbon emission scenario) using simulated PDSI based on Intergovernmental Panel on Climate Change AR4 22‐model ensemble climate. According to our prediction, the WSA of the PPR wetlands will decrease to less than half of the baseline WSA (defined as the mean wetlands WSA of the 2000s) by the mid of the 21st century, and to less than one‐third by the 2080s, and will then slightly increase in the 2090s. This considerable future wetland loss caused only by climate change provides important implication to future wetland management and climate adaptation policy. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
17.
人类活动导致大气中温室气体浓度上升，是全球气候变暖的主要原因之一.本文针对已经连续运行13年的AIRS（Atmospheric Infrared Sounder）卫星反演的对流层中层CO2浓度资料，利用地基观测结果对其进行验证，同时结合多种相关资料对我国区域CO2浓度的时空分布及季节变化进行研究.结果显示：北半球30°N—60°N是CO2浓度高值带，低值中心主要出现在15°S—15°N，140°W向东至100°E的低纬地区.地基观测与AIRS卫星反演结果基本一致，年增长率约为1.926 ppmv·a-1.我国区域CO2浓度空间分布上呈现北高南低的非均匀分布特征，4个高值中心分别位于东北地区西南部、内蒙古西部、新疆地区东部和西部，低值中心在云南和西藏地区.我国区域CO2浓度有明显的季节变化特征，最高值出现在春季，冬夏季次之，秋季最低，其季节演变特点与风场的输送、降水量的清除和植被的吸收等密切相关. 相似文献