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1.
人类活动对气候影响的研究Ⅱ.对东亚和中国气候变化的影响 总被引：21，自引：6，他引：15
系统总结和介绍了20世纪90年代以来作者所开展的有关人类活动对东亚和中国气候影响的一系列研究活动.其中包括温室气体辐射强迫及其气候效应,大气微量气体的全球增温潜能,对流层和平流层气溶胶的辐射气候效应,气候系统外部因子对中国气候影响的总体评估,人类活动对中国和东亚地区未来气候变化的影响,以及20世纪和21世纪东亚及中国的气候变化.同时给出了一系列研究成果,这些研究成果对于正确认识和准确预测东亚地区以及中国气候变化具有十分重要的意义. 相似文献
2.
大气层中温室气体的增加,将会引起全球性的气候变化,进而导致生态、经济、政治方面的严重后果,对温室效应与气候变化关系的研究,已成为世界瞩目的刻不容缓的问题。1温室效应对全球气候影响及预测对全球气候变化的研究表明,人类活动使大气中温室气体（二氧化碳、甲烷、臭氧、氟氯烃、氧化氮、二氧化硫和水汽等）浓度不断增加,使全球温度升高、气候变暖。如果人类不能有效地控制这些温室气体的排放,这种趋势将持续,其增暖效应陆地比海洋强,高纬比低纬显著。全球气候持续变暖将对海平面升高、水资源、农业生态、林业及人类健康等带来… 相似文献
3.
《气候变化研究进展》2010,(5)
<正>很多著名的气候科学家一直在发出警告:持续地往地球大气中释放温室气体会造成危险的后果。但是,科学界显然有不同声音。不少人即便接受了人为活动导致变暖的结论,但对其灾难性后果仍然持反对意见,认为全球升温的负面影响被过分夸大了。 相似文献
4.
本文介绍大气中主要的卤代化合物以及它们对臭氧循环和气候的影响。 水汽与二氧化碳是红外辐射的主要吸收体,对地表的热收支具有很大的影响,所以作为气候变化的因素而受到注目。然而,伴随着特殊的大气成分的变化,气候变化的因子增多,使其更难于预报。大气中卤代化合物浓度的大量增加,可能对全球气候具有相应的效应。近年来,国外已经开展了这方面的探索研究。显然,了解大气中存在哪些卤代化合物,目前的浓度和今后的发展趋向以及它们对气候变化的可能影响(尽管目前知道得还不很确切)是完全必要的。本文根据现有认识水平作一简单介绍,材料虽然并非都是成热的,但是对于进一步开拓研究气候变化问题的思想可能会有所裨益。 相似文献
5.
随着对气候变暖问题认识的逐步深入,人们开始意识到,要为减缓气候变暖而奋斗。但是,这显然不是少数科学家,乃至个别政府机构能够做到的。因为大气中温室气体浓度增加带来的温室效应加剧所造成的气候影响是全球性的,而且温室气体也不是个别国家排放的。因此,气候变化及其应对本身的性质就注定了这是一个全球性的问题。1988 相似文献
6.
加强人影工作 减缓气候变化给人类造成的灾害 总被引：1，自引：0，他引：1
瓦黑提·阿扎买提 《沙漠与绿洲气象(新疆气象)》2003,26(2):45-46
1气候变化及其对人类的影响气候系统是包括大气、海洋、陆地、冰雪以及生物圈在内的庞大系统。引起气候系统变化的原因有多种,概括起来可分为自然的气候波动和人类活动的影响两大类。气候波动主要包括太阳辐射的变化以及火山爆发等。人类活动主要包括人类燃烧化石燃料、毁林等引起的大气中二氧化碳等温室气体浓度的增加,以及陆面覆盖和土地利用的变化等等。在气候系统中没有提到人类,但从19世纪末开始,人类活动已经成为气候变化的重要原因。人类对气候无意识的影响是值得注意的新的因子,正因为这个新因子的出现,打破了原有各个因子之间的平… 相似文献
7.
利用能源经济领域具有权威性的英国石油公司(BP)世界能源统计资料和联合国人口统计资料,通过一些简单的数值计算,初步估算了人为热释放的全球气候强迫。结果表明:当前(2008年)全球年平均人为热释放的气候强迫还不是很大,约为0.031W/m2;但随着人口及能源消费总量的增加,未来人为热释放产生的全球年平均气候强迫将有可能达0.30W/m2。 相似文献
8.
本文综合国内外有关资料, 从全球气候系统辐射能量平衡原理出发, 概述了影响全球气候长期变化的几个主要外部强迫因素：大气上界辐射变化（ 地球轨道形状变化和太阳活动） 、温室气体变化、气溶胶和火山活动、下垫面物理景观变化。分别论述了他们对气候变化的影响机制、辐射效应及作用效果。这些因素多与人类活动有关。 相似文献
9.
关于温室气体浓度变化及其引起的气候变化的几个问题 总被引：9，自引：3，他引：6
阐述了当前全球温室气体浓度的增加及其引起的气候效应,讨论了气候变化研究中存在的许多不确定性,如未来温室气体的浓度如何变化,未来气候如何变化,以及气候影响的评价问题等.最后,强调了未来气候变化基础研究中需要注意的问题.
相似文献
10.
气候变化的归因与预估模拟研究 总被引：14，自引：2，他引：12
本文总结了近五年来中国科学院大气物理研究所在气候变暖的归因模拟与预估研究上的主要进展。研究表明,利用海温、太阳辐射和温室气体等实际强迫因子驱动大气环流模式,能够较为合理地模拟全球平均地表气温在20世纪的演变,但是难以模拟出包括北大西洋涛动／北极涛动和南极涛动在内的高纬度环流的长期变化趋势。利用温室气体和硫酸盐气溶胶等“历史资料”驱动气候系统模式,能够较好地模拟出20世纪后期的全球增暖,但如果要再现20世纪前期(1940年代)的变暖,还需同时考虑太阳辐射等自然外强迫因子。20世纪中国气温演变的耦合模式模拟技巧,较之全球平均情况要低;中国气候在1920年代的变暖机理目前尚不清楚。对于近50年中国东部地区“南冷北暖”、“南涝北旱”的气候变化,基于大气环流模式特别是区域气候模式的数值试验表明,夏季硫酸盐气溶胶的负辐射效应超过了温室气体的增暖效应,从而对变冷产生贡献。但现有的数值模拟证据,不足以说明气溶胶增加对“南涝北旱”型降水异常有贡献。20世纪中期以来,青藏高原主体存在明显增温趋势,温室气体浓度的增加对这种增暖有显著贡献。多模式集合预估的未来气候变化表明,21世纪全球平均温度将继续增暖,增温幅度因不同排放情景而异;中国大陆年均表面气温的增暖与全球同步,但增幅在东北、西部和华中地区较大,冬季升温幅度高于夏季、日最低温度升幅要强于日最高温度;全球增暖有可能对我国中东部植被的地理分布产生影响。伴随温室气体增加所导致的夏季平均温度升高,极端温度事件增多;在更暖的气候背景下,中国大部分地区总降水将增多,极端降水强度加大且更频繁发生,极端降水占总降水的比例也将增大。全球增暖有可能令大洋热盐环流减弱,但是减弱的幅度因模式而异。全球增暖可能不是导致北太平洋副热带－热带经圈环流自20世纪70年代以来变弱的原因。文章同时指出了模式预估结果中存在的不确定性。 相似文献
11.
Possible climatic impacts of land cover transformations,with particular emphasis on tropical deforestation 总被引：1，自引：0，他引：1
The climatic impact of albedo changes associated with land-surface alterations has been examined. The total surface global albedo change resulting from major land-cover transformations (i.e. deforestation, desertification, irrigation, dam-building, urbanization) has been recalculated, modifying the estimates of Sagan et al., (1979). Tropical deforestation (11.1 million ha yr-1, or 0.6% yr-1, Lanly, 1982) ranks as a major cause of albedo change, although uncertainties in the areal extent of desertification could conceivably render this latter process of similar significance. The maximum total global albedo change over the last 30 yr for the various processes lies between 0.000 33 and 0.000 64, corresponding to a global temperature decrease of between 0.06 K and 0.09 K (scaled from the 1-D radiative convective model of Hansen et al., 1981), which falls well below the interannual and longer period variability.An upper bound to the impact of tropical deforestation was obtained by concentrating all vegetation change into a single region. The magnitude of this modification is equivalent to 35–50 yr of global deforestation at the current rate, but centered on the Brazilian Amazon. The climatic consequences of such tropical deforestation were simulated, using the GISS GCM (Hansen et al., 1983). In the simulation, a total area of 4.94 × 106 km2 of tropical moist forest was removed and replaced by a grass/crop cover. Although surface albedo increased from 0.11 to 0.19, the effect upon surface temperature was negligible. However, other climate parameters were altered. Rainfall decreased by 0.5–0.7 mm day-1 and both evapotranspiration and total cloud cover were reduced. The absence of a temperature decrease in spite of the increased surface albedo arises because the reduction in evapotranspiration has offset the effects of radiative cooling. The decrease in cloud cover also counteracts the increase in surface albedo. These locally significant changes had no major impact on regional (Hadley or Walker cells) or the global circulation patterns.We conclude that the albedo changes induced by current levels of tropical deforestation appear to have a negligibly small effect on the global climate. 相似文献
12.
Impact of Climate Change and Variability on Irrigation Requirements: A Global Perspective 总被引：7，自引：1，他引：7
Petra Döll 《Climatic change》2002,54(3):269-293
Anthropogenic climate change does not only affect water resources but also water demand. Future water and food security will depend, among other factors, on the impact of climate change on water demand for irrigation. Using a recently developed global irrigation model, with a spatial resolution of 0.5° by 0.5°, we present the first global analysis of the impact of climate change and climate variability on irrigation water requirements. We compute how long-term average irrigation requirements might change under the climatic conditions of the 2020s and the 2070s, as provided by two climate models, and relate these changes to the variations in irrigation requirements caused by long-term and interannual climate variability in the 20th century. Two-thirds of the global area equipped for irrigation in 1995 will possibly suffer from increased water requirements, and on up to half of the total area (depending on the measure of variability), the negative impact of climate change is more significant than that of climate variability. 相似文献
13.
MODIS反照率产品在模拟北京气温中的应用 总被引：2，自引：1，他引：1
地表反照率是制约地表能量收支平衡的基本因子,其变化会影响气温和降水等气象要素,进而影响区域乃至全球的气候。文中使用WRF模式,设计两组反照率敏感试验,探讨地表反照率参数对近地面2处气温模拟精度的影响。结果表明:(1)当北京地区地表反照率增大(减小)0.05时,气温相应降低(升高)0.1～0.5 K,气温变化从城区到郊区有一个明显的降幅,感热通量和潜热通量也相应减小(增大),且变幅主要为0～13 W/m2;(2)将控制试验和MODIS反照率敏感试验模拟结果与实况对比分析发现,两种试验的模拟结果偏低,但应用卫星反照率产品后,气温升高约0.2～0.7 K,更接近实际,即应用MODIS反照率产品替换WRF模式中原有反照率能进一步提高气温的模拟精度。 相似文献
14.
Günter Lang 《Climatic change》2007,84(3-4):423-439
Motivated by the high abatement costs of the Kyoto Protocol for Germany, this paper is estimating the economic impact of global
warming on agriculture in that country. The hedonic approach is used as theoretical background. Stating that land prices are
– among others – determined by climatic factors, this approach can consequently be used to value global warming. To avoid
a priori restrictions stemming from functional forms, the land price function is modeled as quadratic Box–Cox function that
nests a wide range of specifications. In a second step, the estimated results are used to forecast the impact of climate change.
The results indicate that German farmers will be winners of climate change in the short run, with maximum gains occurring
at a temperature increase of +0.6°C against current levels. In the long run, there may be losses from global warming. However,
the net present value from climate change is under the most probable scenarios positive. 相似文献
15.
Zhengguo Shi Xiaodong Liu Zhisheng An Bingqi Yi Ping Yang Natalie Mahowald 《Climate Dynamics》2011,37(11-12):2289-2301
Northern Tibetan Plateau uplift and global climate change are regarded as two important factors responsible for a remarkable increase in dust concentration originating from inner Asian deserts during the Pliocene?CPleistocene period. Dust cycles during the mid-Pliocene, last glacial maximum (LGM), and present day are simulated with a global climate model, based on reconstructed dust source scenarios, to evaluate the relative contributions of the two factors to the increment of dust sedimentation fluxes. In the focused downwind regions of the Chinese Loess Plateau/North Pacific, the model generally produces a light eolian dust mass accumulation rate (MAR) of 7.1/0.28?g/cm2/kyr during the mid-Pliocene, a heavier MAR of 11.6/0.87?g/cm2/kyr at present, and the heaviest MAR of 24.5/1.15?g/cm2/kyr during the LGM. Our results are in good agreement with marine and terrestrial observations. These MAR increases can be attributed to both regional tectonic uplift and global climate change. Comparatively, the climatic factors, including the ice sheet and sea surface temperature changes, have modulated the regional surface wind field and controlled the intensity of sedimentation flux over the Loess Plateau. The impact of the Tibetan Plateau uplift, which increased the areas of inland deserts, is more important over the North Pacific. The dust MAR has been widely used in previous studies as an indicator of inland Asian aridity; however, based on the present results, the interpretation needs to be considered with greater caution that the MAR is actually not only controlled by the source areas but the surface wind velocity. 相似文献
16.
This study reports the first assessment of the compounding effects of land-use change and greenhouse gas warming effects on our understanding of projections of future climate. An AGCM simulation of the potential impacts of tropical deforestation and greenhouse warming on climate, employing a version of NCAR Community Climate Model (CCM1-Oz), is presented. The joint impacts of tropical deforestation and greenhouse warming are assessed by an experiment in which removal of tropical rainforests is imposed into a greenhouse-warmed climate. Results show that the joint climate changes over tropical rainforest regions comprise large reductions in surface evapotranspiration (by about –180 mm yr–1) andprecipitation (by about –312 mm yr–1) over the Amazon Basin, along with anincrease of surface temperature by +3.0 K. Over Southeast Asia, similar but weaker changes are found in this study. Precipitation is decreased by –172 mmyr–1, together with the surface warming of 2.1 K. Over tropical Africa, changes in regional climate is much weaker and with some different features, such as the increase of precipitation by 25 mm yr–1. Energy budgetanalyses demonstrates that the large increase of surface temperature in the joint experiment is not solely produced by the increase of CO2concentration, but is a joint effect of the reduction of surface evaporation (due to deforestation) and the increase of downward atmospheric longwave radiation (due to the doubling of CO2 concentration). Furthermore, impactsof tropical deforestation on the greenhouse-warmed climate are estimated by comparing a pair of tropical deforestation simulations. It is found that in CCM1-Oz, deforestation has very similar impacts on greenhouse-warmed regional climates as on current climates over tropical rainforest regions. The extra-tropical climatic response to tropical deforestation is identified in both sets of tropical deforestation experiments. Statistically significant responses are seen in the large-scale atmospheric circulation such as changes in the velocity potential and vertically integrated kinetic and potential energy fields. Wave propagation patterns are identified in the large-scale circulation anomalies, which provides a mechanism for interpreting the model responses in the extra-tropics. In addition, this study suggests that land-use change such as tropical deforestation may affect projections of future climate. 相似文献
17.
Coupling between subtropical cloud feedback and the local hydrological cycle in a climate model 总被引：2，自引：1，他引：1
In HadGEM2-A, AMIP experiments forced with observed sea surface temperatures respond to uniform and patterned +4 K SST perturbations with strong positive cloud feedbacks in the subtropical stratocumulus/trade cumulus transition regions. Over the subtropical Northeast Pacific at 137°W/26°N, the boundary layer cloud fraction reduces considerably in the AMIP +4 K patterned SST experiment. The near-surface wind speed and the air-sea temperature difference reduces, while the near-surface relative humidity increases. These changes limit the local increase in surface evaporation to just 3 W/m2 or 0.6 %/K. Previous studies have suggested that increases in surface evaporation may be required to maintain maritime boundary layer cloud in a warmer climate. This suggests that the supply of water vapour from surface evaporation may not be increasing enough to maintain the low level cloud fraction in the warmer climate in HadGEM2-A. Sensitivity tests which force the surface evaporation to increase substantially in the +4 K patterned SST experiment result in smaller changes in boundary layer cloud and a weaker cloud feedback in HadGEM2-A, supporting this idea. Although global mean surface evaporation in climate models increases robustly with global temperature (and the resulting increase in atmospheric radiative cooling), local values may increase much less, having a significant impact on cloud feedback. These results suggest a coupling between cloud feedback and the hydrological cycle via changes in the patterns of surface evaporation. A better understanding of both the factors controlling local changes in surface evaporation and the sensitivity of clouds to such changes may be required to understand the reasons for inter-model differences in subtropical cloud feedback. 相似文献
18.
The impact of climate change on the hydrology of continental surfaces is critical for human activities but the response of
the surface to this perturbation may also affect the sensitivity of the climate. This complex feedback is simulated in general
circulation models (GCMs) used for climate change predictions by their land-surface schemes. The present study attempts to
quantify the uncertainty associated with these schemes and what impact it has on our confidence in the simulated climate anomalies.
Four GCMs, each coupled to two different land-surface schemes, are used to explore the spectrum of uncertainties. It is shown
that, in this sample, surface processes have a significant contribution to our ability to predict surface temperature changes
and perturbations of the hydrological cycle in an environment with doubled greenhouse gas concentration. The results reveal
that the uncertainty introduced by land-surface processes in the simulated climate is different from its impact on the sensitivity
of GCMs to climate change, indeed an alteration of the surface parametrization with little impact on model climate can affect
sensitivity significantly. This result leads us to believe that the validation of land-surface schemes should not be limited
to the current climate but should also cover their sensitivity to variations in climatic forcing.
Received: 24 June 1999 / Accepted: 20 April 2000 相似文献
19.
全球变暖背景下的中国西部地区气候变化研究进展 总被引：9，自引：2，他引：7
全球变暖是19世纪80年代以来,地球的年平均气温和地表温度呈上升趋势的现象.在全球变暖的大背景下,我国的气候也发生了显著的变化.探讨全球变暖背景下中国西部地区的气温、降水、气候转型以及青藏高原对中国气候的影响等,对我国应对气候变化问题有着重要的意义.本文从气温、降水、气候转型以及青藏高原对中国气候的影响等方面概述了近年来中国西部地区气候变化的最新研究进展,并探讨了未来的研究方向. 相似文献
20.
Yasuhiro Ishizaki Hideo Shiogama Seita Emori Tokuta Yokohata Toru Nozawa Tomoo Ogura Manabu Abe Masakazu Yoshimori Kiyoshi Takahashi 《Climatic change》2012,112(2):535-546
To preserve consistency among developed emission scenarios, the scenarios used in climate modeling, and the climate scenarios
available for impact research, the pattern scaling technique is useful technique. The basic assumption of pattern scaling
is that the spatial response pattern per 1 K increase in the global mean surface air temperature (SAT) (scaling pattern) is
the same among emission scenarios, but this assumption requires further validation. We therefore investigated the dependence
of the scaling pattern of the annual mean SAT on GHGs emission scenarios of representative concentration pathways (RCP) and
the causes of that dependence using the Model for Interdisciplinary research on Climate 5 developed by Japanese research community.
In particular, we focused on the relationships of the dependency with effects of aerosols and Atlantic meridional overturning
circulation. We found significant dependencies of the scaling pattern on emission scenarios at middle and high latitudes of
the Northern Hemisphere, with differences of >15 % over parts of East Asia, North America, and Europe. Impact researchers
should take into account those dependencies that seriously affect their research. The mid-latitude dependence is caused by
differences in sulfate aerosol emissions per 1 K increase in the global mean SAT, and the high-latitude dependence is mainly
caused by nonlinear responses of sea ice and ocean heat transport to global warming. Long-term trends in land-use and land-cover
changes did not significantly affect the scaling pattern of annual mean SAT, but they might have an effect at different timescales. 相似文献