CO2浓度渐增对气温影响的敏感性试验     

邹立尧  罗哲贤 《南京气象学院学报》1994,17(4):426-431

使用辐射对流模式，研究了中纬度冬季气温对于ＣＯ２浓度变化的敏感性。结果表明：气温变幅随ＣＯ２浓度渐增呈现先快后慢的非线性特征；气温变幅具有一定的稳定性。  相似文献   

Stratospheric warming effects on the tropical mesospheric temperature field   总被引：1，自引：0，他引：1  

M.G. Shepherd  D.L. Wu  I.N. Fedulina  S. Gurubaran  J.M. Russell  M.G. Mlynczak  G.G. Shepherd 《Journal of Atmospheric and Solar》2007,69(17-18):2309

Temperature observations at 20–90 km height and 5–15°N during the winter of 1992–1993, 1993–1994 and 2003–2004, from the Wind Imaging Interferometer (WINDII) and Microwave Limb Sounder (MLS) experiments on the Upper Atmosphere Research Satellite (UARS) satellite and the Sounding the Atmosphere using Broadband Emission Radiometry (SABER) experiment on the Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) satellite are analyzed together with MF radar winds and UK Meteorological Office (UKMO) assimilated fields. Mesospheric cooling is observed at the time of stratospheric warming at the tropics correlative with stratospheric warming events at middle and high latitudes. Planetary waves m=1 with periods of 4–5, 6–8, 10 and 12–18 days are found to dominate the period. Westward 7- and 16-day waves at the tropics appear enhanced by stationary planetary waves during sudden stratospheric warming events.  相似文献   

多窗谱分析方法及其在全球变暖研究中的应用   总被引：12，自引：0，他引：12  

江志红  屠其璞  施能 《气象学报》2001,59(4):480-490

多窗谱分析方法是一种低方差、高分辨的谱分析方法 ,尤其适合于非线性气候系统中高噪声背景下弱信号、时频演变信号的诊断分析。文中简要地介绍了多窗谱分析方法的基本原理 ,并将其用于近 1 5 0 a来全球及南、北半球温度变化的研究。结果表明 :(1 )在温度呈线性变暖的背景趋势下 ,北半球、全球年平均温度还具有显著的 40～ 70 a的准周期低频振荡 ,它们与变暖过程中的波动性密切相关 ;(2 )年代际振荡信号在北半球温度序列中也相当明显 ,南半球则存在多种低于 5 a尺度的显著振荡周期 ,半球或全球 ENSO振荡分量、QBO周期信号的振幅都具有缓变包络的特性 ;(3 )与传统功率谱估计、最大熵谱估计结果的对比表明 ,多窗谱分析方法方法得到的谱估计分辨力高 ,稳定性强。  相似文献   

新疆积雪对气候变暖的响应   总被引：38，自引：1，他引：38  

李培基 《气象学报》2001,59(4):491-501

积雪对全球变暖的响应是当前正在争论的问题。文中通过地面气象台站和 SMMR微波卫星遥感两种积雪资料所建立的两个独立的积雪序列的一致性 ,证明前者在表现新疆积雪长期变化能力方面具有可靠性。阐明了积雪年际变化特征及其与冬季气温和降水量年际波动的关系 ,检验了积雪长期变化趋势。研究表明 ,虽然近 5 0 a来新疆冬季变暖十分显著 ,尤其 2 0世纪 90年代为最温暖的时期 ,但是积雪并未出现持续减少的现象 ;积雪长期变化表现为显著的年际波动过程叠加在长期缓慢的增加趋势之上。积雪年际波动是冬季降水量和气温两者年际波动共同作用的结果 ;冬季气温和降雪量变化受不同的欧亚环流振荡所控制 ;积雪增加趋势与降雪量趋势相一致 ,这可能是由于全球变暖导致海洋蒸发量增加 ,以及在寒冷干燥气候下积雪对降雪量变化更为敏感的缘故。  相似文献   

不同边界条件对多年冻土上限影响的模型试验研究   总被引：17，自引：10，他引：17  

冯文杰  李东庆  马巍  张鲁新 《冰川冻土》2001,23(4):353-359

在全球气候转暖对多年冻土影响的情景下，开展了在多模式下气温升高对冻土上限的影响试验研究。针对不加抛石遮阳棚、加抛石、加抛石遮阳棚3种情况，地表温度均采取基本温度加2次不同升温冻融循环，每次温控指标逐级提高0.5℃，即地表温度3次变化依次按照-16.1～5.8～-13.3℃、-15.6～6.3～-12.8℃、-15.1～6.8～-12.3℃进行，结果表明，加抛石及遮阳棚对多年冻土上限有着明显的影响，冻土上限的变化与气温基本上呈正相关，为寒区道路工程设计与施工提供了理论参考依据。  相似文献   

北半球50条山地冰川近期的物质平衡状况   总被引：4，自引：0，他引：4       下载免费PDF全文

杨大庆 《水科学进展》1992,3(3):161-165

近期北半球大多数山地冰川的物质平衡为负,冰川普遍退缩,表明北半球气候暖化的趋势.由于区域气候波动和变化的差异性以及冰川对气候变化的敏感性(响应程度)的不同,北半球山地冰川在普遍退缩的背景下具有鲜明的区域特征.  相似文献   

Climate change of the last millennium inferred from borehole temperatures: regional patterns of climatic changes in the Czech Republic — Part III     

L. Bodri  V. ermk 《Global and Planetary Change》1999,21(4):383

Accurate temperature–depth profiles may help to assess the temperature variations associated with the climate changes in the past. Ninety-eight ground surface temperature histories inverted from the temperature–depth borehole logs drilled on the territory of the Czech Republic [Bodri, L., ermák, V., 1995. Climate changes of the last millennium inferred from borehole temperatures: results from the Czech Republic — Part I. Global Planet. Change 11, pp. 111–125; Bodri, L., ermák, V., 1997. Climate changes of the last two millennia inferred from borehole temperatures: results from the Czech Republic — Part II. Global Planet. Change 14, pp. 163–173.] are used to reconstruct the regional patterns of the respective climate change. The climate was mapped for the following periods: 1100–1300 A.D. (Little Climatic Optimum), 1400–1500 A.D., 1600–1700 A.D. (main phase of the Little Ice Age), and for the most recent climate trend after year 1960. Comparison of the obtained maps with the meteorological observations and proxy climatic reconstructions confirmed good applicability of the “geothermal” paleoclimatic reconstructions for the regional studies.  相似文献   

On the Epochal Variability in the Frequency of Cyclones during the Pre-Onset and Onset Phases of the Monsoon over the North Indian Ocean     

P. P. BABURAJ  S. ABHILASH  K. MOHANKUMAR  A. K. SAHAI 《大气科学进展》2020,37(6):634-651

In this paper we examine the epochal changes in the frequency of cyclones over the North Indian Ocean during the pre-onset and onset phases of the monsoon. We consider three epochs; namely, the early(1955-74), middle(1975-94) and recent(1995-2014) epochs. It is found that the number of cyclones in the Bay of Bengal(BOB) decreases throughout the three epochs. Over the Arabian Sea(ARB), however, there is a decrease in the early epoch, before then reaching a minimum in the middle epoch followed by an increase in the recent epoch, thus exhibiting epochal variability. Dynamic and thermodynamic parameters along with Genesis Potential Index(GPI) are examined to understand the frequency variation in cyclogenesis over the ARB and BOB. Over the ARB, thermodynamic factors such as mid-level moisture,surface latent heat flux and sensible heat flux, and dynamic parameters such as lower-level convergence and upper-level divergence, are favorable during the early and recent epochs but unfavorable during the middle epoch, and these results are found to be consistent with the observed epochal variability in the frequency of cyclogenesis. However, all these influential parameters are found to have decreased over the BOB during the entire 60-year period.  相似文献   

The inhibition of marine nitrification by ocean disposal of carbon dioxide   总被引：1，自引：0，他引：1  

Huesemann MH  Skillman AD  Crecelius EA 《Marine pollution bulletin》2002,44(2):142-148

In an attempt to reduce the threat of global warming, it has been proposed that the rise of atmospheric carbon dioxide concentrations be reduced by the ocean disposal of CO2 from the flue gases of fossil fuel-fired power plants. The release of large amounts of CO2 into mid or deep ocean waters will result in large plumes of acidified seawater with pH values ranging from 6 to 8. In an effort to determine whether these CO2-induced pH changes have any effect on marine nitrification processes, surficial (euphotic zone) and deep (aphotic zone) seawater samples were sparged with CO2 for varying time durations to achieve a specified pH reduction, and the rate of microbial ammonia oxidation was measured spectrophotometrically as a function of pH using an inhibitor technique. For both seawater samples taken from either the euphotic or aphotic zone, the nitrification rates dropped drastically with decreasing pH. Relative to nitrification rates in the original seawater at pH 8, nitrification rates were reduced by ca. 50% at pH 7 and more than 90% at pH 6.5. Nitrification was essentially completely inhibited at pH 6. These findings suggest that the disposal of CO2 into mid or deep oceans will most likely result in a drastic reduction of ammonia oxidation rates within the pH plume and the concomitant accumulation of ammonia instead of nitrate. It is unlikely that ammonia will reach the high concentration levels at which marine aquatic organisms are known to be negatively affected. However, if the ammonia-rich seawater from inside the pH plume is upwelled into the euphotic zone, it is likely that changes in phytoplankton abundance and community structure will occur. Finally, the large-scale inhibition of nitrification and the subsequent reduction of nitrite and nitrate concentrations could also result in a decrease of denitrification rates which, in turn, could lead to the buildup of nitrogen and unpredictable eutrophication phenomena. Clearly, more research on the environmental effects of ocean disposal of CO2 is needed to determine whether the potential costs related to marine ecosystem disturbance and disruption can be justified in terms of the perceived benefits that may be achieved by temporarily delaying global warming.  相似文献   

近44 a中国冬夏气温变率及其对区域变暖性的影响   总被引：6，自引：2，他引：4  

吴胜安  江志红  屠其璞 《南京气象学院学报》2002,25(6):830-836

利用近44a中国85个测站冬夏季逐日平均、最高和最低气温序列,研究冬夏季温度季节变率及其时空演变特征,探讨其对区域变暖稳定性的影响。结果表明：冬季,除高原、西南、东北以外的中国大部分地区,温度的季节变率存在显著下降趋势,是近期变暖的稳定区,其中变暖最为稳定、显著的区域是西北、华北地区,东北北部虽变暖幅度很大,但稳定性最差;夏季,长江中下游及其江南地区温度变率存在显著上升趋势,20世纪70年代后年际变幅明显增大,表明该地区80年代降温的稳定性差。  相似文献