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1.
大气科学论著中"量"的运算和"单位"的变化   总被引:2,自引:0,他引:2  
针对大气科学论著中“量和单位”复杂、易错的特点,详细分析了一些“量”的物理意义、推导过程和表达形式。并给出相应的单位。认为在大气科学论著中正确使用“量和单位”是非常必要和重要的。  相似文献   

2.
利用天气动力学原理对2006年7月17日锡盟南部地区及西苏旗出现的暴雨天气过程进行了分析与探讨,结果表明高空处于强暖脊控制,不利于强降水产生的弱对流环境条件下,低空冷涡及地面倒槽仍可为产生暴雨提供辐合上升运动和充沛的水汽条件;而台风"碧利斯"在登陆后长达5天的生命史中,为锡盟"7·17"暴雨过程提供了必要的动力抬升条件,激发了锡盟地区中尺度强降水系统发生、发展.  相似文献   

3.
在有关文件或奖牌中,经常可看到用汉字标示的年月日将“○”字误写为“0”或“O”,如“二000年十月一日”、“二OO一年三月”等,看起来非常别扭.把“○”字误写为“0”或“O”不但看着不舒服,也不符合汉字使用规范.  相似文献   

4.
台风"派比安"分析   总被引:3,自引:1,他引:3  
利用1°×1°NCEP/NCAR再分析资料计算了0606号台风“派比安”的物理量场,结合常规气象资料对“派比安”台风的运动路径、长时间大风以及暴雨特点进行诊断分析,结果表明:1台风过程后期华北大槽减弱北收,副高迅速加强西伸,同时“派比安”旋转风结构中始终存在向西北偏西方向偏转的倾向,副高与台风之间的气压梯度增大,引导了“派比安”向偏西北方向移动;2强散度柱与强涡度柱形成耦合机制,促成了强的垂直上升运动,使台风登陆后中心气压填塞缓慢。台风环流没有出现某一部位突然衰减或增强,是造成大风持续时间长的主要原因;3“派比安”生成于热带辐合带中,台风结构对称,登陆后,一直处在小于10m·s-1的风垂直切变环境之中,水汽源源不断的输入台风环流中,是造成暴雨持续时间长、强度大的主要成因。  相似文献   

5.
目前,我省气象部门采用的文字处理软件基本上是以Word系列为主,特别在办公自动化网络传输中,Word得到广泛运用.在实际运用中笔者发现,有时在对Word文件进行修改以后,尽管只修改了其中一小部分,甚至个别标点符号,但该文件却大了许多,出现了"虚胖"现象;  相似文献   

6.
1998年7月19日深夜-21日凌晨在川中、东部产生了突发性大暴雨过程,本文在对中尺度雨团、地面中尺度低压系统进行了较深入分析的基础上,利用T106的客观分析场对此过程进行分析,发现:过程发生前后,大气的能量、水汽及辐合上升运动等条件有一个急速突变的过程,致使强降水产生.在这次大暴雨过程中,中尺度特征明显,雨团活动频繁.  相似文献   

7.
对比分析0604号强热带风暴与0606号台风的强度变化、环流背景、云系结构以及物理量的分布特点,探讨两个台风暴雨降水的成因。结果表明:0604号强热带风暴虽登陆地点远离广西,但台风低压稳定维持在江西到湖南境内,其倒槽暖式切变进入广西并与西南季风相互作用,不断激发中小尺度降水,产生大范围暴雨;0606号台风正面袭击广西,强度强,登陆后其环境风场衰减慢,移速慢,从而造成大范围的暴雨天气。  相似文献   

8.
粤北"5.09"暴雨过程分析   总被引:2,自引:0,他引:2  
本文通过对造成2001年5月9日韶关暴雨的天气形势、大气物理量场、数值产品应用等特征进行了分析,得出了一些预报体会,在实际预报中有一定的意义。  相似文献   

9.
在副热带高压边缘的西南气流中,由于切变线和低涡的发展产生了大暴雨,其直接原因是华东沿海暖脊的加强,使江南沿海形成较强偏东气流,并与低纬度地区西南气流辐合挤压引起切变线低涡强烈发展的结果.  相似文献   

10.
2002年12月份江门地区出现大范围的冰雹,这在历史资料中是绝无仅有的,本文对这次强对流天气成因进行了分析,分析表明,此次强对流天气是在低层暖湿气流短时加强进退,江南锋生的有利环境背景下发生的。  相似文献   

11.
大气中硝酸盐、硫酸盐、铵和钙的浓度   总被引:2,自引:0,他引:2  
1985年10月,在中国的三个不同地点用太氟龙和尼龙滤膜采样系统观测了硝酸根、硫酸根、铵和钙的浓度。平均而言,硫酸根的摩尔浓度与硝酸根的摩尔浓度之比不到2。考虑到中国燃煤大量排放SO_2这一事实,这一低比值有点出乎预料。在北京钙是最重要的阳离子,而在华北山区的兴隆天文观测站和南方城市长沙气溶胶中铵离子多于钙离子。在北风条件下,兴隆的硫酸根和硝酸根浓度与文献中报道的欧洲和北美的本底值接近。因此,兴隆天文观测站是研究亚洲大陆本底空气的理想地点。  相似文献   

12.
A coupled lattice Boltzmann (LB) model with second-order accuracy is applied to the reduced-gravity, shallow water, 2.5-layer model for wind-driven double-gyre ocean circulation. By introducing the secondorder integral approximation for the collision operator, the model becomes fully explicit. The Coriolis force and other external forces are included in the model with second-order accuracy, which is consistent with the discretization accuracy of the LB equation. The feature of the multiple equilibria solutions is found in the numerical experiments under different Reynolds numbers based on this LB scheme. With the Reynolds number increasing from 3000 to 4000, the solution of this model is destabilized from the anti-symmetric double-gyre solution to the subtropic gyre solution and then to the subpolar gyre solution. The transitions between these equilibria states are also found in some parameter ranges. The time-dependent variability of the circulation based on this LB simulation is also discussed for varying viscosity regimes. The flow of this model exhibits oscillations with different timescales varying from subannual to interannual. The corresponding statistical oscillation modes are obtained by spectral analysis. By analyzing the spatiotemporal structures of these modes, it is found that the subannual oscillation with a 9-month period originates from the barotropic Rossby basin mode, and the interarmual oscillations with periods ranging from 1.5 years to 4.6 years originate from the recirculation gyre modes, which include the barotropic and the baroclinic recirculation gyre modes.  相似文献   

13.
Anthropogenic, Climatic, and Hydrologic Trends in the Kosi Basin, Himalaya   总被引:1,自引:0,他引:1  
A great debate exists concerning theinfluence of land-use and climatic changes onhydrology in the Himalayan region and its adjacentplains. As a representative basin of the Himalayas, westudied basinwide land-use, climatic and hydrologictrends over the Kosi Basin (54,000 km2) in themountainous area of the central Himalayan region. Theassessment of anthropogenic inputs showed that thepopulation of the basin grew at a compound rate ofabout one percent per annum during the past fourdecades. The comparison of land-use data between thesurveys made during the 1960s and 1978–1979 did notreveal noticeable trends in land-use change. Theanalysis of meteorological and hydrological timeseries from 1947 to 1993 showed some increasingtendency of temperature and precipitation. Thestatistical tests of hydrologic trends indicated anoverall decrease in discharge on the Kosi River andits major tributaries. The decreasing trends ofstreamflow were more significant during the low-flowmonths. The statistical analysis of homogeneityshowed that the climatic as well as the hydrologictrends were more localized in nature lacking adistinct basinwide significance.  相似文献   

14.
Climatic change is likely to affect Pacific Northwest (PNW) forests in several important ways. In this paper, we address the role of climate in four forest ecosystem processes and project the effects of future climatic change on these processes across Washington State. First, we relate Douglas-fir growth to climatic limitation and suggest that where Douglas-fir is currently water-limited, growth is likely to decline due to increased summer water deficit. Second, we use existing analyses of climatic controls on tree species biogeography to demonstrate that by the mid twenty-first century, climate will be less suitable for key species in some areas of Washington. Third, we examine the relationships between climate and the area burned by fire and project climatically driven regional and sub-regional increases in area burned. Fourth, we suggest that climatic change influences mountain pine beetle (MPB) outbreaks by increasing host-tree vulnerability and by shifting the region of climate suitability upward in elevation. The increased rates of disturbance by fire and mountain pine beetle are likely to be more significant agents of changes in forests in the twenty-first century than species turnover or declines in productivity, suggesting that understanding future disturbance regimes is critical for successful adaptation to climate change.  相似文献   

15.
Climate change,migration and adaptation in Funafuti,Tuvalu   总被引:1,自引:0,他引:1  
This paper shows the extent to which people in Funafuti – the main island of Tuvalu – are intending to migrate in response to climate change. It presents evidence collected from Funafuti to challenge the widely held assumption that climate change is, will, or should result in large-scale migration from Tuvalu. It shows that for most people climate change is not a reason for concern, let alone a reason to migrate, and that would-be migrants do not cite climate change as a reason to leave. People in Funafuti wish to remain living in Funafuti for reasons of lifestyle, culture and identity. Concerns about the impacts of climate change are not currently a significant driver of migration from Funafuti, and do not appear to be a significant influence on those who intend to migrate in the future.  相似文献   

16.
Abatement cost and benefit projections through 2100are computed, assembled and interpreted with respectto various levels of emission reduction. Mathematicalexpressions describing regional costs and benefits asa function of abatement strategy are developed. Usingthese data and expressions, optimal abatementstrategies are defined for noncooperative andcooperative (Pareto optimal) policies. Thecooperative solution calls for an average emissionsreduction of 16.6 percent over the 1990–2100 period,as compared to 5.8 percent in the noncooperative case. Achieving the cooperative solution would require sidepayments to China and potentially to the U.S., as wellas stringent (though beneficial) restrictions onnon-OECD countries. It is argued that Paretooptimality is technically achievable but possiblyinfeasible in the real world.  相似文献   

17.
Freezing of rainwater on a surface is often caused by nocturnal clearing after precipitation, which goes along with radiative cooling. Forecasting cloudiness, and especially the risk of clearing, on a scale of 1 to 3 h is of interest in the domains of road weather, agriculture, or water management.Cloud amount and the difference between air and surface temperature are important parameters of the radiation balance. In this contribution, we show the relationship between them, proved at several stations all over Switzerland. We found a correlation coefficient of 0.88 and improved it considering other meteorological parameters like wind speed. We conclude that temperature difference is a signature for nocturnal cloudiness.We investigated nocturnal cloudiness for a case from winter 2001/02 in northern Switzerland. An ultra-dense combination of two networks with 70 stations in total is operated, measuring air and surface temperature, wind and other parameters. With the aid of our equations, these measurements where converted into cloud maps, including also precipitation seen by radar. We identified a frontal precipitation area, postfrontal clearing, freezing, and the first clouds of a following frontal passage.All these findings will contribute to a better observation and predictability of surface state and other risks connected with radiative cooling.  相似文献   

18.
从云雾降水物理学的角度学习和分析了一些中国古诗词。内容有:1)分析和统计了唐诗300首和毛泽东诗词中用到云雾雨雪等字的百分比,其分别占总首数的45%和66%;2)列举和分析了描述自然过程、大气过程有云雨雪等字的诗(词)句;3)从现代科学观出发,分析了在一些古诗词中有关云、雨、霜、露等的理解,并作了一些评述;4)对古诗词中直接描述云、雾、雨、雪的内容进行了评论。    相似文献   

19.
不断变化的气候可导致前所未有的极端天气和气候事件。这些事件能否构成灾害,在很大程度上取决于脆弱性和暴露度水平。虽然无法完全消除各种灾害风险,但灾害风险管理和气候变化适应的重点是减少脆弱性和暴露度,并提高对各种潜在极端事件不利影响的恢复力,从而促进社会和经济的可持续发展。全面的灾害风险管理要求更加合理地分配对减灾、灾害管理等方面所付出的努力。过去的主流是强调灾害管理,但目前减灾成为关注焦点和挑战。这种主动积极的灾害风险管理与适应有助于避免未来的风险和灾害,而不仅仅是减少已有的风险和灾害,同时这也是灾害风险管理和气候变化适应更加紧密联系的一个背景。灾害风险管理促进气候变化适应从应对当前的影响中汲取经验,而气候变化适应帮助灾害风险管理更加有效地应对未来变化的条件。  相似文献   

20.
Tackseung Jun 《Climatic change》2017,142(1-2):183-197
Civil conflicts have swept through many parts of sub-Saharan Africa in the past half century. Recently, scholars from backgrounds as diver as climate science, economics, political science, and anthropology have explored the effects of climate change on these civil conflicts, with mixed results. Our empirical results confirm effects of temperature on the incidence of civil conflict. The key findings are as follows: (i) between 1970 and 2012 in sub-Saharan Africa, a high temperature during maize growing season reduced the crop’s yield, which in turn increased the incidence of civil conflict and (ii) future expected warming is expected to increase civil conflict incidence by 33% in the period 2031–2050, and by 100% in the period 2081–3010, compared to levels between 1981 and 2000. These results highlight the importance of sufficient food supplies and adaptation to increased climate warming to facilitate peace in sub-Saharan Africa.  相似文献   

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