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近20年来中国极地大气科学研究进展 总被引：14，自引：0，他引：14
南极、北极和青藏高原是地球上的 3大气候敏感地区 ,是多个国际计划研究全球变化的关键地区。中国的南极和北极实地考察研究 ,分别始于 2 0世纪 80和 90年代 ,起步较晚 ,但近 2 0余年来有较大的进展。极地大气科学考察与研究是极地科学研究的重要组成部分。讫今为止 ,中国已组织了 2 0次南极考察和 3次北极考察 ,建立了中国南极长城站、中山站和北极黄河站等 3个常年科学考察站 ;进行了常规地面气象、Brewer大气臭氧、近地面物理、高层大气物理、冰雪和大气化学等观测 ,获得了较为系统的极地大气科学第一手资料 ;开展了有关极地与全球变化的研究 ,取得了新的进展。南极地区大气温度、臭氧和海冰的气候变化在时间和空间上都是多样的。南极地区的增暖主要发生在南极半岛地区 ,在南极大陆主体并不明显 ,近 10余年来还有降温趋势。中国南极长城站和中山站的观测资料也证实了这一点。此外 ,还揭示了南极半岛西侧和罗斯海外围的海冰变化具有“翘翘板”特征 ,由此定义的南极涛动指数可用来讨论南极海冰状况和海冰关键区的活动 ;用实地考察资料研究了极地不同下垫面的近地面物理和海 -冰 -气相互作用特征 ,给出了边界层特征参数 ;讨论了极地天气气候和大气环境特征及其对东亚大气环流和中国天气气候的影响 ;利用 相似文献
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《中国气象科学研究院年报》1999,(1)
我院承担了该专题的2个子专题：“南极冰雪与大气相互作用过程和辐射特征的观测研究”和“南极臭氧和紫外辐射的监测和变化机制研究”。1999年的研究进展如下：1）对南极中山站用Brewer臭氧光谱仪观测得到的1993－1998年臭氧总量和紫外辐射的分析结果表明,春季出现臭氧低于200 相似文献
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利用2004—2007年三明市主要大气污染物PM10的监测值及气象因子(气压、风速、温度、湿度、降水、蒸发量)观测资料,以及同期08:00 850 hPa天气图资料,定量分析了PM10的突变特征以及突变与气象因子的相关关系。结果表明:PM10突变事件有明显的季节性特征,冬、春季节发生突变的概率较大;当地面气象要素场出现气压下降、风速减小、相对湿度下降、降水量减小而温度上升、蒸发量加大的配置时,PM10易发生正突变,当出现气压上升、风速加大、相对湿度上升、降水量增加而温度下降、蒸发量减小的配置时,PM10易发生负突变;当受大陆高压后部、暖区辐合系统影响时,PM10发生正突变的概率较高,受大陆高压前部、切变线系统影响时,PM10发生负突变的概率较高。 相似文献
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利用卫星和台站观测的南极臭氧资料和NCEP/NCAR再分析资料,分析了南极臭氧近年来的变化特征和影响因子,探讨了南极臭氧洞期间中山站臭氧突变过程与大气动力的作用。结果显示,平流层氯和溴的卤化物当量（EESC）和平流层温度是影响南极臭氧洞面积的关键因子。臭氧总量与EESC和平流层温度均具有显著相关,表明两站虽然都位于臭氧洞边缘,EESC和平流层温度对臭氧总量的变化仍然可以起决定性的作用,同时也验证了EESC参数在东南极大陆沿岸具有适用性。 EESC的年代际变化与臭氧变化趋势相似,臭氧的年际变化与平流层温度关系密切。回归结果表明,2010年后臭氧洞面积逐渐减小,在2070年左右可能恢复到1980年前的水平,但其结果存在很大的不确定性。 相似文献
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南极和北极是地球上的气候敏感地区, 也是多个国际科学计划研究全球气候变化的关键地区。极地大气科学考察与研究是极地科学研究的重要组成部分。中国气象科学研究院的极地大气科学考察与研究始于20世纪80年代, 25年来有较大进展。中国气象科学研究院参加了我国组织的23次南极考察、2次北冰洋考察和3次北极考察; 承担了南极长城站和中山站、北极黄河站气象业务建设和维持, 以及中-澳合作南极冰盖3个无人自动气象站工作; 进行了常规地面气象、Brewer大气臭氧、近地面物理、冰雪和大气化学等观测, 获得了较为系统的极地大气环境资料。开展了有关极地大气科学与全球变化的研究, 在极地天气气候特征及气候变化时空多样性、极地海冰变化和南极海冰涛动、极地近地面物理特征和海-冰-气相互作用、中山站臭氧变化特征及南极臭氧洞和大气化学、气候代用资料获取和古气候环境以及极地大气环境变化对东亚环流和中国天气气候影响等方面的研究取得了新进展。中国极地大气科学正积极通过多学科交叉、走国际合作道路, 努力提高对极地在全球变化中作用的认识水平, 并积极探索极地变化对我国气候、环境的影响。 相似文献
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利用2005年1月\_2010年2月自动气象站的地面风观测资料, 分析了四川新津机场地面风的平均日变化、 月变化\, 季变化及年际变化等, 讨论了地面瞬时风与机场跑道的关系, 并对≥5 m·s-1地面瞬时风的预报进行了探索。结果表明： 机场主要受偏北风、 偏西南风和偏东南风影响, 且偏北风和偏东南方向风速较大。全年较大风主要出现在春季。各季节均盛行偏北风, 秋\, 冬季偏北风出现的频率远大于春\, 夏季。下午风速大, 早晨和夜间风速小。全年平均风速小, 年际差异小, 微风和静风频率高。持续时间较长的≥5 m·s-1地面瞬时风的预报重点在于天气系统的预报上。 相似文献
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近20年来，中国南极科学考察的气象业务取得了长足进展。1985年在南极半岛建立了中国长城气象站；1989年在南极大陆建成了中国中山气象台；2001年与澳大利亚南极局合作在距中山站160km的南极冰盖上安置了LGB-69自动气象站(AWS)。在长城和中山两站开展了常规地面气象观测、站区天气预报服务、气象卫星高分辨率图像传输资料(HRPT)接收等业务；在中山站进行Brewer大气臭氧和紫外辐射(UV-B)等要素的观测；在赴南极考察的航渡期间进行气象观测和预报服务。南极常规气象业务已为研究南极在全球气候变化中的作用积累了丰富资料，为航渡和站区考察项目的实施提供的气象服务保障，为我国南极科学考察和研究事业作出了重要贡献。进一步提高南极气象业务水平，拓展气象业务和大气科学考察研究领域，是今后极地大气科学考察和研究的重要任务。 相似文献
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利用1957～1992年南极地区大气臭氧总量地面观测站资料，对南极地区臭氧的时空变化特征进行了研究。结果表明，虽然近35年来南极地区的大气臭氧有较明显的减小趋势，但在不同地区、时段和季节，其变化趋势也不同。近年来南极地区大气臭氧的显著亏损，主要是由南极臭氧洞的形成和发展所造成的。南极地区的大气臭氧存在明显的年振荡、准20个月和准30个月的振荡周期。臭氧变化与天文日照、平流层温度场、平流层冰晶云及人类活动排放到大气中的氟氯烃和溴化烃等污染物质有关。 相似文献
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Recent studies demonstrate that the Antarctic Ozone Hole has important influences on Antarctic sea ice.While most of these works have focused on effects associated with atmospheric and oceanic dynamic processes caused by stratospheric ozone changes,here we show that stratospheric ozone-induced cloud radiative effects also play important roles in causing changes in Antarctic sea ice.Our simulations demonstrate that the recovery of the Antarctic Ozone Hole causes decreases in clouds over Southern Hemisphere(SH)high latitudes and increases in clouds over the SH extratropics.The decrease in clouds leads to a reduction in downward infrared radiation,especially in austral autumn.This results in cooling of the Southern Ocean surface and increasing Antarctic sea ice.Surface cooling also involves ice-albedo feedback.Increasing sea ice reflects solar radiation and causes further cooling and more increases in Antarctic sea ice. 相似文献
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Antarctica and global change 总被引：2，自引：0，他引：2
W. F. Budd 《Climatic change》1991,18(2-3):271-299
The Antarctic region of the globe is of special importance for a wide range of studies of global change. The IGBP research activities needing special focus for global change should be multidisciplinary, should involve both the geosphere and the biosphere, and should be of global as well as local interest. There are a number of important Antarctic research topics which fit these criteria.A decrease of Antarctic sea ice has a positive feedback on global warming. Reduction in the sea ice also impacts on deep ocean circulation and can give a positive feedback to the increase of atmospheric carbon dioxide by the reduction of a deep ocean sink. Changes in the mass balance of the Antarctic ice sheet impact on global sea level. A unique historic record of past climate and global environmental changes is being obtained from deep core drilling in the Antarctic ice sheet. Decreases of stratospheric ozone are most pronounced over the Antarctic in spring. The impact of increases in ultraviolet radiation on the biosphere can be studied in the Antarctic as a precurser to possible changes developing elsewhere around the globe. Changes in the atmosphere and ocean circulations resulting from the decrease in Antarctic sea ice cover can have important effects on ocean surface temperatures which impact on the climates of the continents.These topics are discussed briefly and a number of Antarctic research areas are highlighted which build on existing or planned international programmes and which can make critical contributions to multidisciplinary studies of global change. 相似文献
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The stratospheric polar vortex strengthening from late winter to spring plays a crucial role in polar ozone depletion. The Arctic polar vortex reaches its peak intensity in mid-winter, whereas the Antarctic vortex usually strengthens in early spring. As a result, the strong ozone depletion is observed every year over the Antarctic, while over the Arctic short-term ozone loss occasionally occurs in late winter or early spring. However, the cause of such a difference in the life cycles of the Arctic and Antarctic polar vortices is still not completely clear. Based on the ERA-Interim reanalysis data, we show a high agreement between the seasonal variations of temperature in the subtropical lower stratosphere and zonal wind in the subpolar and polar lower stratosphere in the Southern Hemisphere. Thus, the spring strengthening of the Antarctic polar vortex can occur due to the seasonal temperature increase in the subtropical lower stratosphere in this period. 相似文献
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An assessment and interpretation of the observed warming of West Antarctica in the austral spring 总被引：1，自引：1，他引：0
We synthesize variability and trends in multiple analyses of Antarctic near-surface temperature representing several independent source datasets and spatially complete reconstructions, and place these into the broader context of the behavior of other components of the climate system during the past 30–50?years. Along with an annual-mean trend during the past 50?years of about 0.1°C/decade averaged over Antarctica, there is a distinct seasonality to the trends, with insignificant change (and even some cooling) in austral summer and autumn in East Antarctica, contrasting with warming in austral winter and spring. Apart from the Peninsula, the seasonal warming is largest and most significant in West Antarctica in the austral spring since the late 1970s. Concurrent trends in sea ice are independent evidence of the observed warming over West Antarctic, with the decrease in sea ice area in the Amundsen and Bellingshausen Seas congruent with at least 50% of the inland warming of West Antarctica. Trends in near surface winds and geopotential heights over the high-latitude South Pacific are consistent with a role for atmospheric forcing of the sea ice and air temperature anomalies. Most of the circulation trend projects onto the two Pacific South American (PSA) modes of atmospheric circulation variability, while the Southern Annular Mode lacks a positive trend in spring that would otherwise cause a cooling tendency. The largest circulation trend is associated with the PSA-1 mode, a wave-train extending from the tropics to the high Southern latitudes. The PSA-1 mode is significantly correlated with SSTs in the southwestern tropical and subtropical Pacific. The increased SSTs in this region, together with the observed increase in rainfall, suggest that anomalous deep convection has strengthened or increased the occurrence of the Rossby wave-train associated with PSA-1. This hypothesis is supported by results from two ensembles of SST-forced atmospheric general circulation model simulations. Finally, the implications of the seasonality, timing, and spatial patterns of Antarctic temperature trends with respect to interpreting the relative roles of stratospheric ozone depletion, SSTs and increased atmospheric concentrations of greenhouse gasses are discussed. 相似文献
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Low-level temperature inversions are a common feature of the wintertime troposphere in the Arctic and Antarctic. Inversion strength plays an important role in regulating atmospheric processes including air pollution, ozone destruction, cloud formation, and negative longwave feedback mechanisms that shape polar climate response to anthropogenic forcing. The Atmospheric Infrared Sounder (AIRS) instrument provides reliable measures of spatial patterns in mean wintertime inversion strength when compared with available radiosonde observations and reanalysis products. Here, we examine the influence of sea ice concentration on inversion strength in the Arctic and Antarctic. Correlation of inversion strength with mean annual sea ice concentration, likely a surrogate for the effective thermal conductivity of the wintertime ice pack, yields strong, linear relationships in the Arctic (r?=?0.88) and Antarctic (r?=?0.86). We find a substantially greater (stronger) linear relationship between sea ice concentration and surface air temperature than with temperature at 850?hPa, lending credence to the idea that sea ice controls inversion strength through modulation of surface heat fluxes. As such, declines in sea ice in either hemisphere may imply weaker mean inversions in the future. Comparison of mean inversion strength in AIRS and global climate models (GCMs) suggests that many GCMs poorly characterize mean inversion strength at high latitudes. 相似文献
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对近30年南极海冰密集度资料的EOF和SVD分析，发现南极地区在罗斯海外围和别林斯高晋海的海冰密集度场存在着“翘翘板”的变化特征，并与ENSO有密切联系。由此定义两个海冰关键区的差值为南极海冰涛动指数（ASOI），ASOI超前SOI和Nino3指数2个月时，其正、负相关系数达到最大，并通过α=0.001的信度检验。ASOI高、低指数阶段对应的南半球海平面气温、气压场和风场的合成分析表明，海冰关键区的异常变化可能引起温度、气压、风场的响应而影响南太平洋的洋流，进而对ENSO的发生、发展产生影响。 相似文献