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1.
1999年全球重大气候事件概述 总被引：13，自引：6，他引：7
１９９９年,全球气候仍持续较常年偏暖。赤道中、东太平洋的强拉尼娜事件维持并发展,对全球特别是热带地区的气候产生了较明显的影响。欧洲、北冬季连续遭受暴风雪袭击,出现严寒天气,夏季又经受了高温热浪的袭击。全球许多地区暴雨频繁,亚洲南部、欧洲中部、北美南部、南美北部以及非洲的一些地区都遇到了严重的洪涝灾害;而北美中部、西亚等地却干旱少雨,发生了凡十年来最严重的旱灾。北美、南亚、澳大利亚东北部先后遭到罕见 相似文献
2.
近50年中国东部夏季降水与贝加尔湖地表气温年代际变化的关系 总被引：11，自引：1，他引：11
最近50年全球变暖,陆地增温幅度大于海洋,主要的增温中心位于亚洲北部、欧洲和北美等地区。因此,全球变暖有可能通过改变大尺度季风环流而影响中国气候变化。利用美国国家航空航天局空间研究中心(GISS)的逐月地表气温资料、NCEP/NCAR再分析资料及中国604个站逐月气温和降水观测资料,重点讨论了1951—2007年中国东部夏季降水与同期的北半球大陆地表气温年代际尺度变化关系。结果表明,近50年中国东部夏季降水异常主要表现为南旱北涝与南涝北旱两者年代际异常之间的转换,但在1996年之后,伴随北方干旱区向南发展,呈现出华北和长江中下游地区降水同时减少的特征。研究发现中国华北地区夏季降水与同期的环贝加尔湖地表气温在年代际尺度上存在显著的负相关关系;贝加尔湖地区地表气温增暖可能导致蒙古高原对流层出现异常的暖性反气旋,使得位于蒙古高原的气旋频数减少和强度减弱。由于华北降水与蒙古气旋的活动直接相关,从而导致华北地区夏季降水的持续性减少。自1996年开始贝加尔湖地区的地表气温进一步升高,导致中国北方干旱化加剧。由于环贝加尔湖地区是过去50年全球变暖的最显著地区之一,因此,全球变暖可能是通过关键区域的温度变化对中国的气候变化产... 相似文献
3.
The radiance lights data in 2006 from the National Oceanic and Atmospheric Administration Air Force Defense Meteorological Satellite Program/Operational Linescan System (DMSP/OLS) and authoritative energy data distributed by the United State Energy Information Administration were applied to estimate the global distribution of anthropogenic heat flux.A strong linear relationship was found to exist between the anthropogenic heat flux and the DMSP/OLS radiance data.On a global scale,the average value of anthropogenic heat flux is approximately 0.03 W m 2 and 0.10 W m 2 for global land area.The results indicate that global anthropogenic heat flux was geographically concentrated and distributed,fundamentally correlating to the economical activities.The anthropogenic heat flux concentrated in the economically developed areas including East Asia,Europe,and eastern North America.The anthropogenic heat flux in the concentrated regions,including the northeastern United States,Central Europe,United Kingdom,Japan,India,and East and South China is much larger than global average level,reaching a large enough value that could affect regional climate.In the center of the concentrated area,the anthropogenic heat flux density may exceed 100 W m 2,according to the results of the model.In developing areas,including South America,Central and North China,India,East Europe,and Middle East,the anthropogenic heat flux can reach a level of more than 10 W m 2 ;however,the anthropogenic heat flux in a vast area,including Africa,Central and North Asia,and South America,is low.With the development of global economy and urban agglomerations,the effect on climate of anthropogenic heat is essential for the research of climate change. 相似文献
4.
We discuss climate impacts of a hypothetical shutdown of the thermohaline circulation (‘THC’) in the 2050s, using the climate model HadCM3. Previous studies have generally focussed on the effects on pre-industrial climate. Here we take into account increased greenhouse gas concentrations according to an IS92a emissions scenario. THC shutdown causes cooling of the Northern Hemisphere of -1.7?C, locally stronger. Over western Europe cooling is strong enough for a return to pre-industrial conditions and a significant increase in the occurrence of frost and snow cover. Global warming restricts the increase in sea ice cover after THC shutdown. This lessens the amount of cooling over NW Europe, but increases it over North America, compared to pre-industrial shutdown. This reflects a non-linearity in the local temperature response to THC shutdown. Precipitation change after THC shutdown is generally opposite to that caused by global warming, except in western and southern Europe, where summer drying is enhanced, and in Central America and southeast Asia, where precipitation is also further reduced. Local rise in sea level after THC shutdown can be large along Atlantic coasts (pm; 25,cm), which would add to the rise caused by global warming. Potentially rapid THC shutdown adds to the range of uncertainty of projected future climate change. 相似文献
5.
E. Roeckner P. Stier J. Feichter S. Kloster M. Esch I. Fischer-Bruns 《Climate Dynamics》2006,27(6):553-571
The past and future evolution of atmospheric composition and climate has been simulated with a version of the Max Planck Institute Earth System Model (MPI-ESM). The system consists of the atmosphere, including a detailed representation of tropospheric aerosols, the land surface, and the ocean, including a model of the marine biogeochemistry which interacts with the atmosphere via the dust and sulfur cycles. In addition to the prescribed concentrations of carbon dioxide, ozone and other greenhouse gases, the model is driven by natural forcings (solar irradiance and volcanic aerosol), and by emissions of mineral dust, sea salt, sulfur, black carbon (BC) and particulate organic matter (POM). Transient climate simulations were performed for the twentieth century and extended into the twenty-first century, according to SRES scenario A1B, with two different assumptions on future emissions of carbonaceous aerosols (BC, POM). In the first experiment, BC and POM emissions decrease over Europe and China but increase at lower latitudes (central and South America, Africa, Middle East, India, Southeast Asia). In the second experiment, the BC and POM emissions are frozen at their levels of year 2000. According to these experiments the impact of projected changes in carbonaceaous aerosols on the global mean temperature is negligible, but significant changes are found at low latitudes. This includes a cooling of the surface, enhanced precipitation and runoff, and a wetter surface. These regional changes in surface climate are caused primarily by the atmospheric absorption of sunlight by increasing BC levels and, subsequently, by thermally driven circulations which favour the transport of moisture from the adjacent oceans. The vertical redistribution of solar energy is particularly large during the dry season in central Africa when the anomalous atmospheric heating of up to 60 W m−2 and a corresponding decrease in surface solar radiation leads to a marked surface cooling, reduced evaporation and a higher level of soil moisture, which persists throughout the year and contributes to the enhancement of precipitation during the wet season. 相似文献
6.
《Global Environmental Change》2006,16(2):207-220
Global anthropogenic sulfur emissions increased until the late 1980s. Existing estimates for 1995 and 2000 show a moderate decline from 1990 to 1995 or relative stability throughout the decade. This paper combines previously published data and new econometric estimates to show a 22% decline over the decade to a level not seen since the mid-1960s. The decline is evident in North America, Western and Eastern Europe, and in the last few years in East and South Asia. If this new trend is maintained, local air pollution problems will be ameliorated but global warming may be somewhat exacerbated. 相似文献
7.
2001年全球重大气候事件概述 总被引：1，自引：0，他引：1
全球气候仍持续偏暖。亚洲大部出现异常冷冬，许多地区遇到数十年未见的风雪严寒；美国冬季也连续遭受暴风雪袭击。东亚、南亚、中亚有西亚发生了大范围的持久干旱，南亚、东南亚夏季暴雨频繁，造成严重洪涝灾害。欧洲、非洲及南美洲的许多国家和地区降水异常偏多，导致不同程度的洪水，俄罗斯西伯利亚地区发生百年不遇的大洪水。北大西洋飓风较常年显著偏多，西北太平洋台风也给沿海地区带来严重灾害。 相似文献
8.
Arctic sea ice and Eurasian climate: A review 总被引：12，自引：0，他引：12
GAO Yongqi SUN Jianqi LI Fei HE Shengping Stein SANDVEN YAN Qing ZHANG Zhongshi Katja LOHMANN Noel KEENLYSIDE Tore FUREVIK SUO Lingling 《大气科学进展》2015,32(1):92-114
The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades,including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian climate.Paleo, observational and modelling studies are covered to summarize several major themes, including: the variability of Arctic sea ice and its controls; the likely causes and apparent impacts of the Arctic sea-ice decline during the satellite era,as well as past and projected future impacts and trends; the links and feedback mechanisms between the Arctic sea ice and the Arctic Oscillation/North Atlantic Oscillation, the recent Eurasian cooling, winter atmospheric circulation, summer precipitation in East Asia, spring snowfall over Eurasia, East Asian winter monsoon, and midlatitude extreme weather; and the remote climate response(e.g., atmospheric circulation, air temperature) to changes in Arctic sea ice. We conclude with a brief summary and suggestions for future research. 相似文献
9.
Irrigation induced surface cooling in the context of modern and increased greenhouse gas forcing 总被引：1，自引：0，他引：1
There is evidence that expected warming trends from increased greenhouse gas (GHG) forcing have been locally ??masked?? by irrigation induced cooling, and it is uncertain how the magnitude of this irrigation masking effect will change in the future. Using an irrigation dataset integrated into a global general circulation model, we investigate the equilibrium magnitude of irrigation induced cooling under modern (Year 2000) and increased (A1B Scenario, Year 2050) GHG forcing, using modern irrigation rates in both scenarios. For the modern scenario, the cooling is largest over North America, India, the Middle East, and East Asia. Under increased GHG forcing, this cooling effect largely disappears over North America, remains relatively unchanged over India, and intensifies over parts of China and the Middle East. For North America, irrigation significantly increases precipitation under modern GHG forcing; this precipitation enhancement largely disappears under A1B forcing, reducing total latent heat fluxes and the overall irrigation cooling effect. Over India, irrigation rates are high enough to keep pace with increased evaporative demand from the increased GHG forcing and the magnitude of the cooling is maintained. Over China, GHG forcing reduces precipitation and shifts the region to a drier evaporative regime, leading to a relatively increased impact of additional water from irrigation on the surface energy balance. Irrigation enhances precipitation in the Middle East under increased GHG forcing, increasing total latent heat fluxes and enhancing the irrigation cooling effect. Ultimately, the extent to which irrigation will continue to compensate for the warming from increased GHG forcing will primarily depend on changes in the background evaporative regime, secondary irrigation effects (e.g. clouds, precipitation), and the ability of societies to maintain (or increase) current irrigation rates. 相似文献
10.
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
11.
近年来,在全球变暖的背景下,极端气候事件特别是极端降水事件,发生频率愈发上升。本文使用美国气候预测中心提供的逐日降水资料,统计分析了1979—2018年期间欧亚大陆各个子区域极端降水事件的时空变化特征。结果表明:1)从气候态的空间分布特征来看,南欧、南亚、东南亚、东亚地区为欧亚大陆全年总降水量高值区,同时也是极端强降水频发地区;而东亚地区青藏高原、中国中西部至蒙古一带,南亚地区印度次大陆以及中亚、西亚等地的部分地区则是连续性干旱事件的高频区,极端强降水事件发生频次较少;2)在21世纪初之后,东南亚、南亚、东亚、北亚、西亚和南欧这6个地区的全年总降水量发生年代际增加,且在研究时段呈显著增加趋势。在过去近40 a,南亚、东亚和中亚的RX1day(日最大降水量)、RX5day(连续5 d最大降水量)、中雨日数(R10mm)、大雨日数(R20mm)自20世纪90年代中期年代际增加,且呈长期增加趋势。南亚、北亚、东亚、中亚这4个地区的最大连续干旱日数在20世纪80年代初显著增加,但长期趋势并不显著。需要指出的是,自2014年起极端强降水事件在东南亚、南亚和东亚地区持续增多,而连续性干旱事件在北欧地区持续增多。 相似文献
12.
In the 20 th century, Eurasian warming was observed and was closely related to global oceanic warming(the first leading rotated empirical orthogonal function of annual mean sea surface temperature over the period 1901–2004). Here, large-scale patterns of covariability between global oceanic warming and circulation anomalies are investigated based on NCEP–NCAR reanalysis data. In winter, certain dominant features are found, such as a positive pattern of the North Atlantic Oscillation(NAO), low-pressure anomalies over northern Eurasia, and a weakened East Asian trough. Numerical experiments with the CAM3.5, CCM3 and GFDL models are used to explore the contribution of global oceanic warming to the winter Eurasian climate. Results show that a positive NAO anomaly, low-pressure anomalies in northern Eurasia, and a weaker-than-normal East Asian trough are induced by global oceanic warming. Consequently, there are warmer winters in Europe and the northern part of East Asia. However, the Eurasian climate changes differ slightly among the three models. Eddy forcing and convective heating from those models may be the reason for the different responses of Eurasian climate. 相似文献
13.
Christoph Schmitz Anne Biewald Hermann Lotze-Campen Alexander Popp Jan Philipp Dietrich Benjamin Bodirsky Michael Krause Isabelle Weindl 《Global Environmental Change》2012,22(1):189-209
The volume of agricultural trade increased by more than ten times throughout the past six decades and is likely to continue with high rates in the future. Thereby, it largely affects environment and climate. We analyse future trade scenarios covering the period of 2005–2045 by evaluating economic and environmental effects using the global land-use model MAgPIE (“Model of Agricultural Production and its Impact on the Environment”). This is the first trade study using spatially explicit mapping of land use patterns and greenhouse gas emissions. We focus on three scenarios: the reference scenario fixes current trade patterns, the policy scenario follows a historically derived liberalisation pathway, and the liberalisation scenario assumes a path, which ends with full trade liberalisation in 2045.Further trade liberalisation leads to lower global costs of food. Regions with comparative advantages like Latin America for cereals and oil crops and China for livestock products will export more. In contrast, regions like the Middle East, North Africa, and South Asia face the highest increases of imports. Deforestation, mainly in Latin America, leads to significant amounts of additional carbon emissions due to trade liberalisation. Non-CO2 emissions will mostly shift to China due to comparative advantages in livestock production and rising livestock demand in the region. Overall, further trade liberalisation leads to higher economic benefits at the expense of environment and climate, if no other regulations are put in place. 相似文献
14.
This paper assesses regional abatement action and costs for two scenarios in which atmospheric greenhouse gas concentrations
stabilise at 450 and 550 ppm CO2-equivalent. It evaluates two allocation schemes: Multi-Stage and Contraction & Convergence. It was found that abatement costs
as percentages of GDP vary significantly by region, with high costs for the Middle East and the former Soviet Union, medium
costs for the OECD regions and low costs or even gains for (other) developing regions. In addition to the abatement costs
they incur, fossil-fuel-exporting regions are also likely to be affected by losses of coal and oil exports while the former
Soviet Union and South America could experience increased bio-energy exports. Especially in the former Soviet Union and Asia,
non-CO2 abatement options are important in the short term in reducing their emissions. Carbon capture and storage, energy efficiency
improvements, bio-energy use and the use of renewables dominate reductions in the long term in all regions. It was found that
the regional costs are influenced more by the assumed stabilisation level and baseline scenario than by the allocation regimes
explored or the assumptions for different technologies. 相似文献
15.
David G. Streets 《Climatic change》2007,81(3-4):313-330
Future global emissions of aerosols will play an important role in governing the nature and magnitude of future anthropogenic climate change. We present in this paper a number of future scenarios of emissions of black carbon (BC) and organic carbon (OC) by world region, which we combine with sulfate (SO4) assessed in terms of the emissions of its precursor, SO2. We find that aerosol emissions from the household and industrial sectors are likely to decline along almost all future pathways. Transportation emissions, however, are subject to complex interacting forces that can lead to either increases or decreases. Biomass burning declines in many scenarios, but the Amazon rainforests remain vulnerable if unsustainable economic growth persists. East Asia is the key region for primary aerosols, and trends in China will have a major bearing on the direction and magnitude of releases of BC (expected reductions in the range of 640–1290 Gg), OC (reductions of 520–1900 Gg), and SO2 (ranging from an increase of 21 Tg to a reduction of 30 Tg). Analysis of joint BC, OC, and SO2 emission changes identifies a number of key world regions and economic sectors that could be effectively targeted for aerosol reductions. 相似文献
16.
The intense interest in the greenhouse effect has stimulated detailed studies of temperature records in North America, Europe, and Australia. In this investigation, the temperature records from the Middle East region (defined here as the land area extending from Morocco to Afghanistan) are investigated over the period 1950–1990. Results reveal a linear, statistically significant, temperature increase of 0.07°C per decade over the study area that may or may not be associated with the concurrent rise in equivalent carbon dioxide from approximately 350 ppm to 430 ppm. Seasonal analyses reveal that most of this increase has occurred in the spring season, moderate amounts of warming occurred in the summer and fall seasons, and virtually no warming has occurred in the winter months. An analysis of spatial controls on these temperature changes reveals a general cooling effect associated with the atmospheric sulfate levels and a warming effect associated with the degree of human-induced desertification. The results of this study may prove useful to policymakers in the Middle East who are confronted with many difficult decisions regarding highly interrelated global warming and energy issues. 相似文献
17.
We used a fully coupled chemistry–climate model(version 3 of the Whole Atmosphere Community Climate Model,WACCM3) to investigate the effect of methane(CH4) emission increases,especially in East Asia and North America,on atmospheric temperature,circulation and ozone(O3). We show that CH4 emission increases strengthen westerly winds in the Northern Hemisphere midlatitudes,accelerate the Brewer–Dobson(BD) circulation,and cause an increase in the mass flux across the tropopause. However,the BD circulation in the tropics between 10?S and 10?N at 100 h Pa weakens as CH4 emissions increase in East Asia and strengthens when CH4 emissions increase in North America. When CH4 emissions are increased by 50% in East Asia and 15% globally,the stratospheric temperature cools by up to 0.15 K,and the stratospheric O3 increases by 45 ppbv and 60 ppbv,respectively. A 50% increase of CH4 emissions in North America(with an amplitude of stratospheric O3 increases by 60 ppbv) has a greater influence on the stratospheric O3 than the same CH4 emissions increase in East Asia. CH4 emission increases in East Asia and North America reduce the concentration of tropospheric hydroxyl radicals(4% and 2%,respectively) and increase the concentration of mid-tropospheric O3(5% and 4%,respectively) in the Northern Hemisphere midlatitudes. When CH4 emissions increase in East Asia,the increase in the tropospheric O3 concentration is largest in August. When CH4 emissions increase in North America,the increase in the O3 concentration is largest in July in the mid-troposphere,and in April in the upper troposphere. 相似文献
18.
Terje Berntsen Jan Fuglestvedt Gunnar Myhre Frode Stordal Tore F. Berglen 《Climatic change》2006,74(4):377-411
Today's climate policy is based on the assumption that the location of emissions reductions has no impact on the overall climate
effect. However, this may not be the case since reductions of greenhouse gases generally will lead to changes in emissions
of short-lived gases and aerosols. Abatement measures may be primarily targeted at reducing CO2, but may also simultaneously reduce emissions of NOx, CO, CH4 and SO2 and aerosols. Emissions of these species may cause significant additional radiative forcing. We have used a global 3-D chemical
transport model and a radiative transfer model to study the impact on climate in terms of radiative forcing for a realistic
change in location of the emissions from large-scale sources. Based on an assumed 10% reduction in CO2 emissions, reductions in the emissions of other species have been estimated. Climate impact for the SRES A1B scenario is
compared to two reduction cases, with the main focus on a case with emission reductions between 2010 and 2030, but also a
case with sustained emission reductions. The emission reductions are applied to four different regions (Europe, China, South
Asia, and South America). In terms of integrated radiative forcing (over 100 yr), the total effect (including only the direct
effect of aerosols) is always smaller than for CO2 alone. Large variations between the regions are found (53–86% of the CO2 effect). Inclusion of the indirect effects of sulphate aerosols reduces the net effect of measures towards zero. The global
temperature responses, calculated with a simple energy balance model, show an initial additional warming of different magnitude
between the regions followed by a more uniform reduction in the warming later. A major part of the regional differences can
be attributed to differences related to aerosols, while ozone and changes in methane lifetime make relatively small contributions.
Emission reductions in a different sector (e.g. transportation instead of large-scale sources) might change this conclusion
since the NOx to SO2 ratio in the emissions is significantly higher for transportation than for large-scale sources. The total climate effect
of abatement measures thus depends on (i) which gases and aerosols are affected by the measure, (ii) the lifetime of the measure
implemented, (iii) time horizon over which the effects are considered, and (iv) the chemical, physical and meteorological
conditions in the region. There are important policy implications of the results. Equal effects of a measure cannot be assumed
if the measure is implemented in a different region and if several gases are affected. Thus, the design of emission reduction
measures should be considered thoroughly before implementation. 相似文献
19.
Aerosols make a considerable contribution to the climate system through their radiative and cloud condensation nuclei effects, which underlines the need for understanding the origin of aerosols and their transport pathways. Seasonal distribution of mineral dust around the globe and its correlation with atmospheric circulation is investigated using satellite data, and meteorological data from ECMWF. The most important sources of dust are located in North Africa, the Middle East and Southwest Asia with an observed summer maximum, and East Asia with a spring peak. Maximum dust activity over North Africa and the Middle East in summer is attributed to dry convection associated with the summertime low-pressure system, while unstable weather and dry conditions are responsible for the spring peak in dust emission in East Asia. Intercontinental transport of mineral dust by atmospheric circulation has been observed, including trans-Atlantic transport of North African dust, trans-Pacific transport of Asian dust, and transport of dust from the Middle East across the Indian Ocean. The extent of African dust over the Atlantic Ocean and its latitudinal variation with season is related to the large-scale atmospheric circulation, including seasonal changes in the position of the intertropical convergence zone (ITCZ) and variation of wind patterns. North African aerosols extend over longer distances across the North Atlantic in summer because of greater dust emission, an intensified easterly low level jet (LLJ) and strengthening of the Azores-Bermuda anticyclonic circulation. Transport of East Asian aerosol is facilitated by the existence of a LLJ that extends from East Asia to the west coast of North America. 相似文献
20.
1997年全球重大气候事件概述 总被引：1，自引：0，他引：1
近年来,全球气候持续偏暖,１９９７年又成为一个多世纪以来最暖的一年。年内赤道中、东太平洋发生了一次本世纪最强的厄尔尼诺事件,全球气候受到重大影响,特别是热带地区出现了大范围的气候异常,高温干旱、暴雨洪水事件此起彼伏,连续不断,造成严重灾害。欧洲、北美前冬和春季严寒多雪;欧洲夏季暴雨频繁,中欧发生了百年不遇的特大洪水;中国北部和朝鲜出现罕见的持续高温干旱天气;美国和加拿大边境地区发生了一百多年来最严 相似文献