共查询到20条相似文献，搜索用时 31 毫秒
1.
Joos F Plattner GK Stocker TF Marchal O Schmittner A 《Science (New York, N.Y.)》1999,284(5413):464-467
A low-order physical-biogeochemical climate model was used to project atmospheric carbon dioxide and global warming for scenarios developed by the Intergovernmental Panel on Climate Change. The North Atlantic thermohaline circulation weakens in all global warming simulations and collapses at high levels of carbon dioxide. Projected changes in the marine carbon cycle have a modest impact on atmospheric carbon dioxide. Compared with the control, atmospheric carbon dioxide increased by 4 percent at year 2100 and 20 percent at year 2500. The reduction in ocean carbon uptake can be mainly explained by sea surface warming. The projected changes of the marine biological cycle compensate the reduction in downward mixing of anthropogenic carbon, except when the North Atlantic thermohaline circulation collapses. 相似文献
2.
Ocean salinities reveal strong global water cycle intensification during 1950 to 2000 总被引：3，自引：0，他引：3
Fundamental thermodynamics and climate models suggest that dry regions will become drier and wet regions will become wetter in response to warming. Efforts to detect this long-term response in sparse surface observations of rainfall and evaporation remain ambiguous. We show that ocean salinity patterns express an identifiable fingerprint of an intensifying water cycle. Our 50-year observed global surface salinity changes, combined with changes from global climate models, present robust evidence of an intensified global water cycle at a rate of 8 ± 5% per degree of surface warming. This rate is double the response projected by current-generation climate models and suggests that a substantial (16 to 24%) intensification of the global water cycle will occur in a future 2° to 3° warmer world. 相似文献
3.
全球气候变暖的主要原因在于大气中碳浓度的急速升高。为应对全球气候变暖,以低碳为特征的新发展模式成为目前减少温室气体排放,应对全球气候变暖的根本途径。农业生态系统作为最大的人工生态系统,是重要的碳排放源之一。农业活动与气候变暖关系密切,农业生态系统已成为温室气体的第二大来源。本文以三峡库区为例,在分析了库区农业发展面临问题的基础上,探讨了库区发展低碳循环生态农业的意义,提出了库区低碳循环生态农业发展的一般模式及减少农业生产碳排放的五种对策,即推广免耕法、稻田水旱轮作,适度排水放干、发展以沼气为核心的农村新能源系统、发展高效生态循环种养农业和培育新型农民。 相似文献
4.
How much more rain will global warming bring? 总被引：2，自引：0，他引：2
Climate models and satellite observations both indicate that the total amount of water in the atmosphere will increase at a rate of 7% per kelvin of surface warming. However, the climate models predict that global precipitation will increase at a much slower rate of 1 to 3% per kelvin. A recent analysis of satellite observations does not support this prediction of a muted response of precipitation to global warming. Rather, the observations suggest that precipitation and total atmospheric water have increased at about the same rate over the past two decades. 相似文献
5.
利用四川省139个站点1961～2004年月平均气温和降水资料,并选取九寨沟、海螺沟、峨眉山、蜀南竹海4个旅游景区的气象站点,统计分析了其在全球变暖的背景下的气候变化趋势,进而研究了气候变暖对四川旅游气候资源的影响。结果表明,20世纪90年代以来,与全球变暖相对应,四川地区年均气温呈上升趋势、年降水量呈下降趋势,6个景点的气候变化趋势也基本有类似的响应,这对于以水为景、以气为景的旅游景区(如九寨)的可持续发展提出了挑战。但是冬暖气候在导致降水量减少、冰川面积减少、积雪量减少、雪线上升的同时,也提供了开展冬季旅游、重构现有旅游格局、挖掘新的旅游资源、拓展新的特色旅游空间的机遇。在此基础上,研究提出了主动适应全球变暖的气候响应,大力开展冬季旅游的建议。 相似文献
6.
目前,我国粮食生产正遭受以非对称性增温为特征的气候变暖影响,以春冬季和夜间升温明显为特征的非对称性增温过程与我国主要粮食作物小麦的生育期基本重叠,因此,亟须明确夜间增温对小麦优质高产的影响,为准确判断和预测全球气候变暖背景下农田生态系统对夜间增温的响应程度与趋势以及制定对策提供科学依据。综述了夜间增温对小麦物候期、农艺性状、产量、品质及土壤微生物、养分含量、呼吸等方面的影响,并对夜间增温对小麦-土壤系统影响的未来研究方向进行展望,以期为气候变暖背景下小麦安全生产研究方向的确立及粮食安全生产措施的制定提供理论依据。 相似文献
7.
An optimal transition path for controlling greenhouse gases 总被引：1，自引：0，他引：1
Nordhaus WD 《Science (New York, N.Y.)》1992,258(5086):1315-1319
Designing efficient policies to slow global warming requires an approach that combines economic tools with relations from the natural sciences. The dynamic integrated climate-economy (DICE) model presented here, an intertemporal general-equilibrium model of economic growth and climate change, can be used to investigate alternative approaches to slowing climate change. Evaluation of five policies suggests that a modest carbon tax would be an efficient approach to slow global warming, whereas rigid emissions- or climate-stabilization approaches would impose significant net economic costs. 相似文献
8.
Improved surface temperature prediction for the coming decade from a global climate model 总被引：9，自引：0，他引：9
Smith DM Cusack S Colman AW Folland CK Harris GR Murphy JM 《Science (New York, N.Y.)》2007,317(5839):796-799
Previous climate model projections of climate change accounted for external forcing from natural and anthropogenic sources but did not attempt to predict internally generated natural variability. We present a new modeling system that predicts both internal variability and externally forced changes and hence forecasts surface temperature with substantially improved skill throughout a decade, both globally and in many regions. Our system predicts that internal variability will partially offset the anthropogenic global warming signal for the next few years. However, climate will continue to warm, with at least half of the years after 2009 predicted to exceed the warmest year currently on record. 相似文献
9.
Forests and climate change: forcings, feedbacks, and the climate benefits of forests 总被引：12，自引：0，他引：12
Bonan GB 《Science (New York, N.Y.)》2008,320(5882):1444-1449
The world's forests influence climate through physical, chemical, and biological processes that affect planetary energetics, the hydrologic cycle, and atmospheric composition. These complex and nonlinear forest-atmosphere interactions can dampen or amplify anthropogenic climate change. Tropical, temperate, and boreal reforestation and afforestation attenuate global warming through carbon sequestration. Biogeophysical feedbacks can enhance or diminish this negative climate forcing. Tropical forests mitigate warming through evaporative cooling, but the low albedo of boreal forests is a positive climate forcing. The evaporative effect of temperate forests is unclear. The net climate forcing from these and other processes is not known. Forests are under tremendous pressure from global change. Interdisciplinary science that integrates knowledge of the many interacting climate services of forests with the impacts of global change is necessary to identify and understand as yet unexplored feedbacks in the Earth system and the potential of forests to mitigate climate change. 相似文献
10.
近年来,随着温室效应的加剧,全球气候变暖问题日益突出,对农业生产带来了严重影响。全球气候变暖是多种因素综合作用的结果,人们最关心的是起决定性作用的一种或几种因素。分析表明：自然因素是影响全球气候变暖的基本因素,而人为因素是主导因素。在此基础上,探讨了减缓和控制全球气候变暖的主要措施,如减少温室气体排放,提高现有能源的利用效率,加强新能源的开发等。 相似文献
11.
气候变暖对我国水稻生产的综合影响及其应对策略 总被引：4，自引：0，他引：4
气候变暖已是不争的事实,预计到21世纪末全球地表平均气温仍将上升1.5℃以上。水稻是我国最重要的口粮作物,全国80%以上的人口以稻米为主食,探明气候变暖对我国“口粮绝对安全”的潜在影响意义重大。作者依据多年的田间增温试验及长期观察,并结合国内外现有研究,阐明了我国粮食主产区气候变暖的基本态势,总结发现温度升高1.5℃对我国水稻生产的潜在影响正负参半,并取决于具体的稻作季节和地区。但是,随着水稻种植制度调整,尤其是南方双季稻种植面积下降,温度升高对我国水稻生产的负面影响将逐步递增。最后,作者提出了应对气候变暖的气候智慧型稻作技术创新建议,并展望了该研究领域的重点内容和方向。 相似文献
12.
Simpson RH 《Science (New York, N.Y.)》1973,181(4103):899-907
The subjective approach to hurricane prediction of yesteryear has given way to the automation of many facets of prediction, leaving the forecaster with more time to reason dynamically in making the final adjustments to the official track derived from a hierarchy of computer-generated guidances. The most important task immediately ahead is to develop and apply better diagnostic procedures to help the forecaster identify the guidance sources which are most likely to contain the truth, and to help assure that his final decision will either succeed or fail safely. The ultimate prediction method for both hurricane development and movement will probably need to simulate not only the circulation of the hurricane but the interaction of the cloud clusters in its vortex with the largescale environment. Assuming that this can be effectively done, the most important further handicap will be the problem of describing the initial conditions. The development of a model which will dependably simulate the behavior of the three hurricanes in ten that turn out to be bad actors will not likely become operational in the near future. The most troubling problem in applying such a model-and it would have to be tested for years over a range of many storm types and conditions before becoming fully operational-is that the more complex the model is the more inscrutable the results are and the more difficult it becomes to identify the condition in which computational failure is probable. It would appear, therefore, that engineering approache to prediction and diagnostic procedures of evaluation will dominate the methodology of hurricane forecasting for a number of years to come. 相似文献
13.
Otto-Bliesner BL Marshall SJ Overpeck JT Miller GH Hu A 《Science (New York, N.Y.)》2006,311(5768):1751-1753
In the future, Arctic warming and the melting of polar glaciers will be considerable, but the magnitude of both is uncertain. We used a global climate model, a dynamic ice sheet model, and paleoclimatic data to evaluate Northern Hemisphere high-latitude warming and its impact on Arctic icefields during the Last Interglaciation. Our simulated climate matches paleoclimatic observations of past warming, and the combination of physically based climate and ice-sheet modeling with ice-core constraints indicate that the Greenland Ice Sheet and other circum-Arctic ice fields likely contributed 2.2 to 3.4 meters of sea-level rise during the Last Interglaciation. 相似文献
14.
生长模型耦合气候模式模拟是研究气候变化对农业生产影响的有效途径。本文基于3种典型浓度路径排放情景（RCP）下11个国际耦合模式比较计划第五阶段（CMIP5）全球气候模式（GCMs）的气候预估结果,以1971-2000年观测资料作为气候资料基准值（baseline）,利用LARS WG天气发生器形成包含RCP26、RCP45、RCP85情景下2050s（2041-2060年）和2070s（2061-2080年）时段的气候预估逐日数据集合,分析了浙江省杭州、金华两个代表站点的气候资源变化特征,以气候模式耦合水稻机理模型ORYZA2000方法,集合模拟评估了气候变化对浙江水稻生产的影响。结果表明,未来浙江代表站点杭州和金华的平均气温均会升高,预估2070s时段杭州、金华分别平均升温1.65～3.56、1.75～3.67 ℃,高温热害发生加剧。在仅考虑未来气候变化的条件下,随着温度升高,代表站点的水稻生育期相对基准期缩短。不考虑CO2浓度增加对水稻产量的肥效作用,无论早稻、晚稻、单季稻,其产量相对于基准年份均普遍减产,且高排放情景下的减产幅度明显大于低排放情景。 相似文献
15.
Hurricane intensity and eyewall replacement 总被引：3，自引：0，他引：3
Observations made during the historic 2005 hurricane season document a case of "eyewall replacement." Clouds outside the hurricane eyewall coalesce to form a new eyewall at a greater radius from the storm center, and the old eyewall dies. The winds in the new eyewall are initially weaker than those in the original eyewall, but as the new eyewall contracts, the storm reintensifies. Understanding this replacement mechanism is vital to forecasting variations in hurricane intensity. Processes in the "moat" region between the new and old eyewall have been particularly unclear. Aircraft data now show that the moat becomes dynamically similar to the eye and thus is converted into a region inimical to survival of the inner eyewall. We suggest that targeting aircraft to key parts of the storm to gain crucial input to high-resolution numerical models can lead to improvements in forecasting hurricane intensity. 相似文献
16.
Schneider SH 《Science (New York, N.Y.)》1994,263(5145):341-347
Projected changes in the Earth's climate can be driven from a combined set of forcing factors consisting of regionally heterogeneous anthropogenic and natural aerosols and land use changes, as well as global-scale influences from solar variability and transient increases in human-produced greenhouse gases. Thus, validation of climate model projections that are driven only by increases in greenhouse gases can be inconsistent when one attempts the validation by looking for a regional or time-evolving "fingerprint" of such projected changes in real climatic data. Until climate models are driven by time-evolving, combined, multiple, and heterogeneous forcing factors, the best global climatic change "fingerprint" will probably remain a many-decades average of hemi-spheric- to global-scale trends in surface air temperatures. Century-long global warming (or cooling) trends of 0.5 degrees C appear to have occurred infrequently over the past several thousand years-perhaps only once or twice a millennium, as proxy records suggest. This implies an 80 to 90 percent heuristic likelihood that the 20th-century 0.5 +/- 0.2 degrees C warming trend is not a wholly natural climatic fluctuation. 相似文献
17.
Stott PA Tett SF Jones GS Allen MR Mitchell JF Jenkins GJ 《Science (New York, N.Y.)》2000,290(5499):2133-2137
A comparison of observations with simulations of a coupled ocean-atmosphere general circulation model shows that both natural and anthropogenic factors have contributed significantly to 20th century temperature changes. The model successfully simulates global mean and large-scale land temperature variations, indicating that the climate response on these scales is strongly influenced by external factors. More than 80% of observed multidecadal-scale global mean temperature variations and more than 60% of 10- to 50-year land temperature variations are due to changes in external forcings. Anthropogenic global warming under a standard emissions scenario is predicted to continue at a rate similar to that observed in recent decades. 相似文献
18.
东北地区主要粮食作物对气候变化的响应及其产量效应 总被引：5，自引：0，他引：5
综述了在全球气候变暖背景下,东北地区农业气候资源、农业气象灾害的变化特征以及主要农作物对气候变化的响应。结果表明,气候变暖给东北地区农业带来的影响利弊共存,主要表现为东北地区主要农作物生长季节温度升高、热量资源增加,适宜农作物生长的时期延长、适种区域扩大,为作物的光温生产潜力以及产量的提高提供了潜在的可能。但由于光照及水资源的限制以及CO2浓度的增加而引发的温室效应,对农作物的产量和品质也产生了负面影响。极端天气事件增加,农作物生态环境恶化,干旱、洪涝、盐碱化速度加快,尤其是近几年受全球变暖的影响,东北地区主要农作物受干旱灾害的影响最为明显。降水总量减少和降水分布不均匀,使东北地区成为受气候变化影响最敏感和脆弱地区之一。 相似文献
19.
Robert Mendelsohn 《农业科学学报》2014,13(4):660-665
Asian agriculture is responsible for two thirds of global agricultural GDP. There have been numerous studies exploring the impact of climate change on crops in specific locations in Asia but no study has yet analyzed crops across the entire continent. This study relies on a Ricardian study of China that estimated climate coefficients for Chinese crops. These coefficients are then used to interpolate potential climate damages across the continent. With carbon fertilization, the model predicts small aggregate effects with a 1.5℃ warming but damages of about USS84 billion with 3℃ warming. India is predicted to be especially vulnerable. 相似文献
20.
气候变暖影响区域水循环与粮食安全的研究进展 总被引：1，自引：0，他引：1
综述了气候变暖对水循环、粮食作物生产和粮食安全影响的研究进展。未来气候变暖造成的热浪以及作物生长季节温度的不确定变化导致的农业减产,将严重威胁世界的粮食安全。近些年许多地区热浪增强、强降水事件增多、干旱持续时间延长,表明了全球应对气候变暖采取减排和适应对策的紧迫性和复杂性。减缓温室气体的排放是全世界的共同责任,而适应气候变暖所采取的相应对策则是区域行为,因而难度很大。世界各国应该共同合作,集合世界的力量应对全球变暖的挑战。 相似文献