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1.
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   

2.
《大气与海洋》2013,51(1):101-118
Abstract

A number of recent sea‐ice and ocean changes in the Arctic and subarctic regions are simulated using the global University of Victoria (UVic) Earth System Climate Model version 2.6. This is an intermediate complexity model which includes a three‐dimensional ocean model (MOM 2.2), an energy‐moisture balance model for the atmosphere with heat and moisture transport, and a dynamic‐thermodynamic sea‐ice model with elastic‐viscous‐plastic rheology. The model is first spun up for 1800 years with monthly wind stress forcing derived from the National Centers for Environmental Prediction (NCEP) climatology winds and a pre‐industrial atmospheric CO2 concentration of 280 ppm. After a second spin‐up for the period 1800–1947 with daily climatology winds‐tress forcing, and a linearly increasing atmospheric CO2 concentration, the model is run with interannually varying wind stresses for the period 1948–2002 with an average forcing interval of 2.5 days and an exponentially increasing atmospheric CO2 concentration varying from 315 to 365 ppm. However, the analysis of the model output is only carried out for the years 1955–2002.

The simulated maximum and minimum sea‐ice areas for the Arctic are within 6% of the observed climatologies for the years 1978–2001. The model output also shows a small downward trend in sea‐ice extent, which, however, is smaller than has been observed during the past few decades. In addition, the model simulates a decrease in sea‐ice thickness in the SCICEX (SCientific ICe EXpeditions) measurement area in the central Arctic that is consistent with, but smaller than, that observed from submarine sonar profiling data.

The observed variability and magnitude of the export of sea ice through Fram Strait is quite well captured in the simulation. The change in correlation between the North Atlantic Oscillation (NAO) index and the sea‐ice export around 1977 as found in a data study by Hilmer and Jung (2000) is also reproduced. Within the Arctic basin the model simulates well the patterns and the timing of the two major regimes of wind‐forced sea‐ice drift circulation (cyclonic and anticyclonic) as found earlier by Proshutinsky and Johnson (1997). The influence of variations in the Fram Strait ice export on the strength of the North Atlantic thermohaline circulation and surface air temperature are also determined. In particular, it is shown that 3–4 years after a large ice export, the maximum meridional overturning streamfunction decreases by more than 10%.

The temperature and salinity increase at depths of 200–300 m, as observed in the eastern Arctic by Morison et al. (1998), between the USS Pargo cruise in 1993 and the Environmental Working Group (EWG) Joint USRussian Arctic Atlas climatology for the years 1948–87, are just visible in the model simulation. The increases are more noticeable, however, when the ocean model data are averaged over the pentade 1995–2000 and compared with model data averaged over the pentade 1955–60. The fact that these, and some of the other modelled changes, are smaller than the observed changes can likely be attributed to the relatively coarse resolution of the UVic Earth System Climate Model (3.6°E‐W and 1.8°N‐S). Nevertheless, the fact that the model captures qualitatively many of the recent sea‐ice and ocean changes in the Arctic suggests that it can be successfully used to investigate other Arctic‐North Atlantic Ocean climate interactions during past and future eras.  相似文献   

3.
Significant CO2 concentration disturbances with an amplitude of 150 ppm are observed in October–November in the region of North Pole-35 drifting ice station over the continental slope of the Arctic Ocean. A local maximum of the CO2 concentration disturbances is observed in April; it is connected with a change in the regime of the sea ice deformation at that time of the year in the western Arctic basin. Changes in the CO2 concentration have oscillations at the frequency of oceanic tides. Several episodes of the initial phase of CO2 release into the near-ice surface atmosphere in October 2007 are recorded. The CO2 amount released into the atmosphere as a result of ice formation in the Arctic Ocean is a significant quantity in the total balance of the CO2 release on the global scale and accounts for approximately 30% of the anthropogenic release of CO2 per year.  相似文献   

4.
A climate model experiment was conducted using the HadCM3 climate model and a scenario in which the atmospheric CO2 concentration was increased over 70 years from pre-industrial concentrations to 4 times this level and then stabilised for more than a 1,000 years. During the period of stabilisation the global atmospheric surface temperatures continued to rise as the deep oceans adjusted towards a new equilibrium. However, even after 1,000 years this new equilibrium had not been reached. During the first 600 years, Arctic and Antarctic winter sea ice thickness and area covered declined with a significant impact on the global radiation budget. After this period the area of the Arctic covered by sea ice entered a 150 years period during which time it underwent a series of oscillations. Following the oscillation the centre of the Arctic basin became ice free throughout the year. A sensitivity experiment demonstrates that although the sea ice extent can be greatly reduced through the artificial heating of the mixed layer, prior to the onset of the oscillatory phase the ice recovers over 15 years. Understanding the causes of this oscillatory phase may elucidate the mechanisms of variability in the Arctic in the present climate and in future policy relevant scenarios. We have investigated the atmospheric and oceanic forcing on the ice during the oscillatory phase, and find that the behaviour is linked to a redistribution of Arctic Ocean heat stores.  相似文献   

5.
郑帅  孙博  邱振鹏  吴文星 《气象科学》2024,44(2):199-209
为了进一步了解全球变暖背景下北极海冰与东亚冬季风的关系及其变化,本文选用东亚冬季风北模态及南模态作为东亚冬季风指数,利用滑动相关分析、回归分析及合成分析研究了全球变暖背景下1953—2021年北极海冰密集度与东亚冬季风关系的变化特征及其机制。结果表明:11月巴伦支海海冰密集度与东亚冬季风北模态之间的关系发生了显著变化,从1962—1977年显著正相关转为1983—1999年显著负相关,2000年以后两者无显著关系。1962—1977年11月巴伦支海海冰偏多对应东亚冬季风偏强,这是大气环流影响海冰的结果,11月的大气环流异常特征维持到了冬季,使得欧亚大陆上空大气呈现出北极涛动(Arctic Oscillation,AO)负位相,在增强东亚冬季风的同时将中高纬大陆干冷空气输送至巴伦支海,在表面风应力的作用下巴伦支海海冰增多。1983—1999年则由前一时期的大气环流影响海冰变为海冰影响大气环流,11月巴伦支海海冰显著减少在冬季激发出了北极涛动负位相,加强东亚大槽及东亚高空西风急流,从而使得东亚冬季风偏强。2000年以后北极海冰与东亚冬季风北模态的关系明显减弱,此时东亚冬季风与北极涛动的负相关关系更为显著。  相似文献   

6.
Recent work in modelling climatic changes due to increased atmospheric CO2 has shown the maximum change to occur in the polar regions as a result of seasonal reductions in sea ice coverage. Typically, sea ice thermodynamics is modelled in a very simple way, whereby the storage of both sensible and latent heat within the ice is ignored, and the effects of snow cover on conductivity and on surface albedo and of oceanic heat flux on bottom ablation may also be neglected. This paper considers whether omission of these processes is justified within the context of quantitatively determining regional climatic changes. A related question, whether omission of ice dynamics can be justified, is not considered.Relatively complete one-dimensional models of sea-ice thermodynamics have previously been developed and tested for a variety of environmental conditions by Maykut and Untersteiner (1969, 1971) and by Semtner (1976). A simpler model which neglects the storage of sensible and latent heat is described in the Appendix to Semtner (1976). In that model, the errors in annual-mean ice thickness which would arise from neglect of heat storage can be compensated by increases in albedo and in conductivity. Here we examine the seasonal cycle of ice thickness predicted by such a model and find significant errors in phase (one month lead) and in amplitude (50% overestimate). The amplitude errors are enhanced as snowfall and oceanic heat flux diminish (or are neglected). This suggests that substantial errors may occur in climate simulations which use very simple formulations of sea ice thermodynamics, whereby early and excessive melting exaggerates the seasonal disappearance of sea ice.To illustrate the above point, two models are configured to examine the local response of Arctic sea ice to a quadrupling of atmospheric CO2. The first model neglects a number of physical processes and mimics the behavior of sea ice found in Manabe and Stouffer (1980), both for present and enhanced levels of CO2. The more complete second model gives a better simulation of Arctic ice for the present level of CO2 and shows a reduced response to CO2 quadrupling relative to that in Manabe and Stouffer (1980). In particular, the change in surface temperature is cut by a factor of two. In view of this result, a more complete treatment of sea ice thermodynamics would seem warranted in further studies of climate change. Only a minor computational increase is required.A portion of this study is supported by the U.S. Department of Energy as a part of its Carbon Dioxide Research Program.The National Center for Atmospheric Research is sponsored by the National Science Foundation.  相似文献   

7.
Summary Outgoing longwave radiation (OLR) as seen from satellite (NOAA-series), and sea ice concentration in Mer Dumont d'Urville, Eastern Antarctica were analyzed. For the time period 1974–1990 available radiative flux data showed a slight increase of 1.8 W/m2 or 1% for the period. If thistrend should continue — trends over a 16-year period in any geophysical data is a rather questionable concept in isolation — a 4°C warming would be observed from space for this polar region over a century. The observed increase is, however, in agreement with Dumont d'Urville, the only ground station within the study area, which displayed a similar temperature increase (Periard and Pettré, 1991). Further it is in agreement with the general temperature increase which has been observed for the high southern latitudes (Boden et al., 1990). In addition, models of climatic change due to increased CO2 and other trace gases predict for polar regions values of similar size.Sea ice concentration showed a slight decrease for the time period 1974–1989, for which data were available. However, a relationship existed between the radiative flux and the ice concentration, not only for the actual data, but also for the deviation series with the annual cycles removed. A correlation factor of –0.74 was found; the sensitivity for an increase of 10% in ice concentration was –2.9 W/m2. This represents a temperature change as seen from space of about 1°C for a 10% change in sea ice concentration.With 7 Figures  相似文献   

8.
S. J. Kim 《Climate Dynamics》2004,22(6-7):639-651
The role of reduced atmospheric CO2 concentration and ice sheet topography plus its associated land albedo on the LGM climate is investigated using a coupled atmosphere-ocean-sea ice climate system model. The surface cooling induced by the reduced CO2 concentration is larger than that by the ice sheet topography plus other factors by about 30% for the surface air temperature and by about 100% for the sea surface temperature. A large inter-hemispheric asymmetry in surface cooling with a larger cooling in the Northern Hemisphere is found for both cases. This asymmetric inter-hemispheric temperature response is consistent in the ice sheet topography case with earlier studies using an atmospheric model coupled with a mixed-layer ocean representation, but contrasts with these results in the reduced CO2 case. The incorporation of ocean dynamics presumably leads to a larger snow and sea ice feedback as a result of the reduction in northward ocean heat transport, mainly as a consequence of the decrease in the North Atlantic overturning circulation by the substantial freshening of the North Atlantic convection regions. A reversed case is found in the Southern Ocean. Overall, the reduction in atmospheric CO2 concentration accounts for about 60% of the total LGM climate change.  相似文献   

9.
《大气与海洋》2013,51(3):224-237
Abstract

The University of Victoria's (UVic) Earth System Climate model is used to conduct equilibrium atmospheric CO2 sensitivity experiments over the range 200–1600 ppm in order to explore changes in northern hemisphere snow cover and feedbacks on terrestrial surface air temperature (SAT). Simulations of warmer climates predict a retreat of snow cover over northern continents, in a northeasterly direction. The decline in northern hemisphere global snow mass is estimated to reach 33% at 600 ppm and 54% at 1200 ppm. In the most northerly regions, annual mean snow depth increases for simulations with CO2 levels higher than present day. The shift in the latitude of maximum snowfall is estimated to be inversely proportional to the CO2 concentration. The northern hemisphere net shortwave radiation changes are found to be greater over land than over the ocean, suggesting a stronger albedo feedback from changes in terrestrial snow cover than from changes in sea ice. Results also reveal high sensitivity of the snow mass balance under low CO2 conditions. The amplification feedback (defined as the zonal SAT anomaly caused by doubling CO2 divided by the equatorial anomaly) is greatest for scenarios with less than 300 ppm, reaching 1.9 at the pole for 250 ppm. The stronger feedback is attributed to the significant albedo changes over land areas. The simulation with 200 ppm triggers continuous accumulation of snow ('glaciation') in regions which, according to paleo‐reconstructions, were covered by ice during the last glacial cycle (the Canadian Arctic, Scandinavia, and the Taymir Peninsula).  相似文献   

10.
采用Hadley中心的海冰密集度资料和中国160站气温资料,对冬季北极海冰变化的主要模态进行了分析,定义了5个关键海区,重点讨论了冬季北极海冰异常与中国冬季气温的关系。结果表明,冬季北极海冰变化主要表现为第一模态,即太平洋、大西洋的海冰反位相分布。海冰变化的关键区域为区域Ⅰ巴伦支海、区域Ⅱ格陵兰海、区域Ⅲ戴维斯海峡、区域Ⅳ白令海以及区域Ⅴ鄂霍次克海。中国冬季平均气温、冬季最低气温、冬季最高气温均与北极关键海区的海冰异常有显著相关,但是与其对应的海区有所不同。  相似文献   

11.
冬季北极海冰与中国同期气温的关系   总被引:3,自引:0,他引:3  
采用Hadley中心的海冰密集度资料和中国160站气温资料,对冬季北极海冰变化的主要模态进行了分析,定义了5个关键海区,重点讨论了冬季北极海冰异常与中国冬季气温的关系.结果表明,冬季北极海冰变化主要表现为第一模态,即太平洋、大西洋的海冰反位相分布.海冰变化的关键区域为区域Ⅰ巴伦支海、区域Ⅱ格陵兰海、区域Ⅲ戴维斯海峡、区...  相似文献   

12.
Arctic sea ice responds to atmospheric forcing in primarily a top-down manner, whereby near-surface air circulation and temperature govern motion, formation, melting, and accretion. As a result, concentrations of sea ice vary with phases of many of the major modes of atmospheric variability, including the North Atlantic Oscillation, the Arctic Oscillation, and the El Niño-Southern Oscillation. However, until this present study, variability of sea ice by phase of the leading mode of atmospheric intraseasonal variability, the Madden–Julian Oscillation (MJO), which has been found to modify Arctic circulation and temperature, remained largely unstudied. Anomalies in daily change in sea ice concentration were isolated for all phases of the real-time multivariate MJO index during both summer (May–July) and winter (November–January) months. The three principal findings of the current study were as follows. (1) The MJO projects onto the Arctic atmosphere, as evidenced by statistically significant wavy patterns and consistent anomaly sign changes in composites of surface and mid-tropospheric atmospheric fields. (2) The MJO modulates Arctic sea ice in both summer and winter seasons, with the region of greatest variability shifting with the migration of the ice margin poleward (equatorward) during the summer (winter) period. Active regions of coherent ice concentration variability were identified in the Atlantic sector on days when the MJO was in phases 4 and 7 and the Pacific sector on days when the MJO was in phases 2 and 6, all supported by corresponding anomalies in surface wind and temperature. During July, similar variability in sea ice concentration was found in the North Atlantic sector during MJO phases 2 and 6 and Siberian sector during MJO phases 1 and 5, also supported by corresponding anomalies in surface wind. (3) The MJO modulates Arctic sea ice regionally, often resulting in dipole-shaped patterns of variability between anomaly centers. These results provide an important first look at intraseasonal variability of sea ice in the Arctic.  相似文献   

13.
Abstract

A study is presented of the seasonal and interannual variability of Arctic sea‐ice extent over the 32‐year period 1953–84. The data set used consists of monthly sea‐ice concentration values given on a 1°‐latitude grid and represents a 7‐year extension of the 25‐year data set analysed by Walsh and Johnson (1979). By focussing attention on the variability in seven distinct subregions that circumscribe the polar region, a number of interesting spatial patterns emerge in the regional seasonal cycles and anomalies of ice coverage. For example, the time‐scale of the smoothed anomaly fluctuations varies from a 4–6 year cycle in the western Arctic (e.g. the Beaufort Sea) to a decadal one in the eastern Arctic (e.g. the Barents Sea). Also, in agreement with earlier studies, a significant out‐of‐phase relationship was found between the 25‐month smoothed anomalies in the Beaufort and Chukchi Sea region and the Greenland Sea. It is proposed that this behaviour is related to atmospheric pressure anomalies associated with the see‐saw in winter air temperature between northern Europe and western Greenland. Finally, a particularly large 9‐year ice anomaly in the Greenland Sea that was centred on 1968 appears to have evolved into a substantial 4‐year Labrador Sea anomaly that peaked in 1972. Both of these anomalies coincided with the passage of the “ Great Salinity Anomaly”, which traversed cyclonically around the subpolar gyre in the northern North Atlantic during the period 1968–82.  相似文献   

14.
基于第六次耦合模式比较计划(CMIP6),使用新一代全球模式BCC-CSM2-MR的历史试验和未来共享社会经济路径(SSPs)数据,依据Hadley中心的海表面温度和海冰密集度数据及NCEP/NCAR I再分析资料,评估了BCC-CSM2-MR模式对北极海冰及北极气候的模拟能力,并对未来变化进行了预估.结果表明:BCC...  相似文献   

15.
Fifty flask air samples were taken during April 1986 from a NOAA WP-3D Orion aircraft which flew missions across a broad region of the Arctic as part of the second Arctic Gas and Aerosol Sampling Program (AGASP II). The samples were subsequently analyzed for both carbon dioxide (CO2) and methane (CH4). The samples were taken in well-defined layers of Arctic haze, in the background troposphere where no haze was detected, and from near the surface to the lower stratosphere. Vertical profiles were specifically measured in the vicinity of Barrow, Alaska to enable comparisons with routine surface measurements made at the NOAA/GMCC observatory. Elevated levels of both methane and carbon dioxide were found in haze layers. For samples taken in the background troposphere we found negative vertical gradients (lower concentrations aloft) for both gases. For the entire data set (including samples collected in the haze layers) we found a strong positive correlation between the methane and carbon dioxide concentrations, with a linear regression slope of 17.5 ppb CH4/ppm CO2, a standard error of 0.6, and a correlation coefficient (r2) of 0.95. This correlation between the two gases seen in the aircraft samples was corroborated by in situ surface measurements of these gases made at the Barrow observatory during March and April 1986. We also find a similar relationship between methane and carbon dioxide measured concurrenty for a short period in the moderately polluted urban atmosphere of Boulder, Colorado. We suggest that the strong correlation between methane and carbon dioxide concentrations reflects a common source region for both, with subsequent long-range transport of the polluted air to the Arctic.  相似文献   

16.
秋季北极海冰对中国冬季气温的影响   总被引:7,自引:0,他引:7  
利用海冰资料、中国地面气候资料、环流特征量资料及NCEP/NCAR再分析资料,研究了秋季北极海冰变化对中国冬季平均气温、日气温变率以及异常低温天气的影响。分析结果表明,秋季北极海冰异常偏多年中国冬季常为暖冬;异常偏少年中国冬季常为冷冬,且异常低温天气出现频率更高,常发生低温灾害事件。秋季北极海冰通过影响后期的北半球极涡、东亚冬季风和西伯利亚高压进而影响中国冬季的平均气温,且通过影响冬季异常强西伯利亚高压的出现频次,影响中国冬季异常低温天气的发生频次。合成分析结果表明,秋季北极海冰异常偏少年的冬季,中国以北亚欧大陆高纬度的偏北风较强,且中国及其以北的中高纬度地区空气异常偏冷,导致极地和高纬度的冷空气易向南爆发,造成中国冬季气温偏低,异常低温天气频发。  相似文献   

17.
利用Hadley海冰密集度资料和NCEP/NCAR再分析资料,分析了北极海冰融冰量及其与大气变量年际关系的年代际变化。结果表明,北极海冰存在显著的年代际变化,且有较强的区域性。东西伯利亚海和波弗特海海冰融冰量的平均值变大且方差增大,格陵兰岛以东洋面海冰融冰量的量值和变率均在减弱。对3个不同气候时段内北极海冰融冰量进行EOF分解,前两个模态均在3个气候时段发生显著的年代际变化,东西伯利亚海海冰融冰量的增加与EOF第一模态年代际变化相关,而EOF第二模态则明显造成了波弗特海海冰的年代际消融。并且,与之相应的大气环流也出现了明显的年代际变化,它们与AO/NAO的年际关系也存在年代际转折,融冰量第二模态与AO的年际关系更为紧密,1960—1990年第二模态与AO的相关系数仅为0.186,而1980—2010年相关系数已升高至0.367。整个北冰洋的海冰融冰量与AO的年际关系也出现了年代际增强,尤其是东西伯利亚地区海冰融冰量与AO的年际关系发生了年代际增强,1980—2010年两者相关达到了0.4以上。而波弗特海融冰量与AO相关系数变化较大,1960—1990年其的相关系数高达-0.488,1980年后却减少至0.161。然而AO却未发生明显的年代际变化。造成北极海冰融冰量及其与大气变量年际关系发生年代际变化的主要因子之一是波弗特高压,其年代际减弱使得极区向东西伯利亚海和波弗特海的海冰输送减弱,导致这两个区域海冰减少,使得AO与北极海冰的年际关系发生了年代际转折。  相似文献   

18.
Geometric and aerodynamic roughness of sea ice   总被引:2,自引:0,他引:2  
The aerodynamic drag of Arctic sea ice is calculated using surface data, measured by an airborne laser altimeter and a digital camera in the marginal ice zone of Fram Strait. The influence of the surface morphology on the momentum transfer under neutral thermal stratification in the atmospheric boundary layer is derived with the aid of model concepts, based on the partitioning of the surface drag into a form drag and a skin drag. The drag partitioning concept pays attention to the probability density functions of the geometric surface parameters. We found for the marginal ice zone that the form drag, caused by floe edges, can amount to 140% of the skin drag, while the effect of pressure ridges never exceeded 40%. Due to the narrow spacing of obstacles, the skin drag is significantly reduced by shadowing effects on the leeward side of floe edges. For practical purposes, the fractional sea-ice coverage can be used to parameterize the drag coefficientC dn, related to the 10 m-wind. C dnincreases from 1.2 · 10-3 over open water to 2.8 · 10-3 for 55% ice coverage and decreases to 1.5 · 10-3 for 100% ice coverage.Aircraft turbulence measurements are used to compare the model values of C dnwith measureents. The correlation between measured and modelled drag coefficients results in r 2 = 0.91, where r is the correlation coefficient.  相似文献   

19.
Submarine and satellite observations show that the Arctic Ocean ice cover has undergone a large thickness reduction and a decrease in the areal extent during the last decades. Here the response of the Arctic Ocean ice cover to changes in the poleward atmospheric energy transport, F wall, is investigated using coupled atmosphere-ice-ocean column models. Two models with highly different complexity are used in order to illustrate the importance of different internal processes and the results highlight the dramatic effects of the negative ice thickness—ice volume export feedback and the positive surface albedo feedback. The steady state ice thickness as a function of F wall is determined for various model setups and defines what we call ice thickness response curves. When a variable surface albedo and snow precipitation is included, a complex response curve appears with two distinct regimes: a perennial ice cover regime with a fairly linear response and a less responsive seasonal ice cover regime. The two regimes are separated by a steep transition associated with surface albedo feedback. The associated hysteresis is however small, indicating that the Arctic climate system does not have an irreversible tipping point behaviour related to the surface albedo feedback. The results are discussed in the context of the recent reduction of the Arctic sea ice cover. A new mechanism related to regional and temporal variations of the ice divergence within the Arctic Ocean is presented as an explanation for the observed regional variation of the ice thickness reduction. Our results further suggest that the recent reduction in areal ice extent and loss of multiyear ice is related to the albedo dependent transition between seasonal and perennial ice i.e. large areas of the Arctic Ocean that has previously been dominated by multiyear ice might have been pushed below a critical mean ice thickness, corresponding to the above mentioned transition, and into a state dominated by seasonal ice.  相似文献   

20.
Based on the simulated ice thickness data from 1949 to 1999, monthly mean temperature data from 160 stations, and monthly mean 1°×1° precipitation data reconstructed from 749 stations in China from 1951 to 2000, the relationship between the Arctic sea ice thickness distribution and the climate of China is analyzed by using the singular value decomposition method. Climate patterns of temperature and precipitation are obtained through the rotated empirical orthogonal function analysis. The results are as follows. (1) Sea ice in Arctic Ocean has a decreasing trend as a whole, and varies with two major periods of 12-14 and 16-20 yr, respectively. (2) When sea ice is thicker in central Arctic Ocean and Beaufort-Chukchi Seas, thinner in Barents-Kara Seas and Baffin Bay-Labrador Sea, precipitation is less in southern China, Tibetan Plateau, and the north part of northeastern China than normal, and vice versa. (3) When sea ice is thinner in the whole Arctic seas, precipitation is less over the middle and lower reaches of Yellow River and north part of northeastern China, more in Tibetan Plateau and south part of northeastern China than normal, and the reverse is also true. (4) When sea ice is thinner in central Arctic Ocean, East Siberian Sea, Beaufort-Chukchi Seas, and Greenland Sea; and thicker in Baffin Bay-Labrador Sea, air temperature is higher in northeastern China, southern Tibetan Plateau, and Hainan Island than normal. (5) When sea ice is thicker in East Siberian Sea 5 months earlier, thinner in Baffin Bay-Labrador Sea 7-15 months earlier, air temperature is lower over the north of Tibetan Plateau and higher in the north part of northwestern China than normal, and a reverse correlation also exists.  相似文献   

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