首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到17条相似文献,搜索用时 62 毫秒
1.
丁一汇 《物理》2009,38(02):71-83
全球气候变化是一个复杂的科学问题,它涉及到气候系统或地球系统的变化,不但需要考虑它们所包含的这些系统内各部分本身的变化,以及它们之间复杂的相互作用,而且还需考虑物理与地球生物化学等许多过程.文章主要讨论全球气候变化中的物理问题,主要有三个方面:(1)辐射传输和全球辐射平衡:不论是由于自然的原因或人类活动(如太阳活动与火山爆发以及温室气体排放增加导致的温室效应加强)一旦破坏全球的辐射平衡,则会引起气候变化,这是气候变化的主要原因与驱动力;(2)大气波动和气候变化的内部变率:除上述外强迫的作用外,气候变化还可由气候系统内部的变率引起,这包括大气内部变率和耦合气候变率.它们主要是通过产生各种大气的波动而实现的.其中最重要的是罗斯贝(Rossby)波.它们的传播和不稳定发展是造成气候变化的另一个原因;(3)气候系统的混沌性质和可预报性:数值预报模式的预报结果对初始场很敏感,即初始场的微小误差可导致完全不同的预报结果,同时模式中物理过程描述的真实程度也影响预报的结果.大气的这种混沌性质限制了天气的可预报性在2周以内.但气候预测由于明显受外强迫的作用,可使大气的混沌时效延长到月、季、年、几十年甚至上百年.为了减少由初始场误差和模式不完善而造成的预报误差,目前气候预报是采用多初值和多模式的集合预报方法,因而气候预测实际上是一种概率预报.  相似文献   

2.
锂离子电池中的物理问题   总被引:9,自引:0,他引:9  
陈立泉 《物理》1998,27(6):354-357
锂离子电池是一种性能优越的新型可充放电池.文章在简述了它的原理和特性之后,着重介绍了所涉及的一些物理问题,诸如嵌入物理、载流子输运、渗流、分形和相变等,以期对锂离子电池有更深入的理解  相似文献   

3.
在物理模型的教学中应注意一些问题。 1 掌握物理模型的准确内涵 例如:质点是一个物理模型,可看成质点的物体实际上往往并不很小,因此不能将它和几何点简单地等同起来,也不能将它和微观粒子(如电子等)混同起来,就是说要注意物理模型的内涵和外延及它们之间的关系。  相似文献   

4.
锂离子电池中的物理问题及其研究进展   总被引:5,自引:0,他引:5  
施思齐  欧阳楚英  王兆翔 《物理》2004,33(3):182-185
锂离子电池作为一种性能优越的新型可充放电池已经或将要在移动通信、手提式计算机和电动汽车等诸多领域获得广泛的应用 .然而与锂离子电池相关的物理问题却往往被人们忽视 .例如 ,如何从本质上来提高正极材料的体相电子电导率 ,而不是在正极活性物质中添加炭黑之类的电子导电材料 .文章将着重针对与锂离子电池相关的物理问题 ,介绍近年来的主要进展 ,以期待对锂离子电池有更深入的了解 .  相似文献   

5.
6.
声波测井中的物理问题   总被引:6,自引:0,他引:6  
文章从声波测井的基本概念入手,介绍了什么是声波测井,其基本原理是什么,声波测井中的主要物理问题是什么,还从几个侧面介绍了声波测井的基本应用和未来的发展趋势,包括传统的电缆测井、目前国外流行的随钻声波测井以及具有应用前景但是尚处于研究阶段的震电测井.文章向从事物理研究的工作者概述了声波测井相关的物理问题和研究的发展现状,为打算涉入声波测井领域研究或者对相关领域研究感兴趣的读者提供了一些基本素材和知识.  相似文献   

7.
王秀明  张海澜  何晓  丛健生  张秀梅 《物理》2011,40(02):79-87
文章从声波测井的基本概念入手,介绍了什么是声波测井,其基本原理是什么,声波测井中的主要物理问题是什么,还从几个侧面介绍了声波测井的基本应用和未来的发展趋势,包括传统的电缆测井、目前国外流行的随钻声波测井以及具有应用前景但是尚处于研究阶段的震电测井.文章向从事物理研究的工作者概述了声波测井相关的物理问题和研究的发展现状,为打算涉入声波测井领域研究或者对相关领域研究感兴趣的读者提供了一些基本素材和知识.  相似文献   

8.
叶玮玮 《技术物理教学》2005,13(3):41-41,44
随着科学技术的发展,自行车经过多次重大改革逐渐变为现代的式样但是不管自行车如何演变,其中运用的基本物理知识是相同的,本文对自行车各部件的物理问题作一剖析.  相似文献   

9.
等效思想在解决物理问题中的应用   总被引:1,自引:0,他引:1  
等效思想,就是从事物的等同效果出发,将复杂物理事物的本身规律转化为等效的、简单的、易于研究的物理事物的思维方法.这种方法在物理学的研究中应用十分广泛,且行之有效.按等同效果形式的不同,一般可分为物理过程的等效、物理作用的等效、物理本质的等效和物理模型的等效等4种.  相似文献   

10.
解答物理问题,通常通过物理概念和规律列出数学方程,然后通过一系列数学计算求出结果.这种解法通常称常规解法.这种解法,一般计算过程冗长,繁琐,稍不留神易出差错,似有淡化物理意义之嫌.物理,即以物说理.解答物理问题,贵在以物说理.解答物理题,如果尽量少列(或不列)数学方程,代之主要用物理语言(概念和规律)说理,求出结果.这种解法,笔者称"物理解法".跟常规解法相比较,具有列式少、物理意义凸显、计算简便、少出错等优点.下举三例均通过两种解法,对比展示物理解法之长处.  相似文献   

11.
Atmospheric greenhouse effect in the context of global climate change   总被引:1,自引:0,他引:1  
Summary Great interest in the problem of the atmospheric greenhouse effect (not only in scientific publications, but also in mass media), on the one hand, and the undoubtfully overemphasised contribution of the greenhouse effect to the global climate change, on the other hand, motivate a necessity to analyse the role which the greenhouse effect plays as a factor of climate change. Significant progress in the analysis of existing observational data as well as succesful development of numerical climate modelling which have been achieved during the recent few years create a basis for a new survey of the atmospheric greenhouse effect in the context of global climate change. Such a survey is the principal purpose of this paper. After discussing a notion of the greenhouse effect, the detailed analysis of the present-day and paleoclimatic observational data has been conducted with subsequent consideration of numerical modelling results. A special attention has been paid to assessments of the greenhouse warmingvs. aerosol cooling. Then possibilities of the early detection of a greenhouse climate signal have been analysed and a few comments on the global climate observing system have been made with the general conclusion that more observations and further numerical modelling efforts are necessary to more reliably assess the contributions of various mechanisms to the observed global climate changes. It is only in the context of a coupled totality of significant climate forming factors and processes that the contribution of the greenhouse effect may be estimated.  相似文献   

12.
基于启发式分割算法检测华北和全球气候变化的特征   总被引:17,自引:0,他引:17       下载免费PDF全文
全球变化已成为当代科学界瞩目的新领域,气候变化是其研究的核心内容之一,它受到各国政府的极大重视.气候突变是气候变化的重要表现形式之一,目前对气候突变的研究主要针对代用资料,运用传统的统计学方法进行处理,尽管取得了不少进展,但气候系统的非线性、多层次性和非平稳性对分析和检测气候突变的方法提出了较高的要求.众所周知,气候系统可能是由多个不同区域气候子系统构成的复杂体系,因而局地和全球气候变化之间必然存在一定的内在联系,但目前关于这方面研究的理论和方法还较少.介绍了一种适合非线性和非平稳时间序列的突变检测新方法 关键词: 突变 启发式分割算法 人为变率 小冰期 全球变化  相似文献   

13.
Summary The report prepared by the Intergovernmental Panel on Climate Change (IPCC) for the Second World Climate Conference contains well-weighted assessments of the present-day state of climate studies and of the possible consequences of climate change. Since IPCC's report is supposed to be a basis for working out an International Framework Convention on Climate Change, an analysis has been made of a number of drawbacks in the consideration of the biosphere as an interactive component of the climatic system, as well as of socio-economic impacts of biospheric changes on climate change. Some thoughts have been expressed on the key components of a convention on climate change.  相似文献   

14.
A major and pressing problem is to understand how, and how fast, the Earth's climate has changed in the past, with and without human influences on the global carbon cycle. Magnetic, remanence-acquiring, minerals, mostly iron oxides and sulphides, occur ubiquitously in sediments. They can act as sensitive recorders of past climates, because as climate has varied (from glacial to interglacial, for example), the mineralogy, magnetic domain state, composition and source of these minerals has varied. Here, the magnetic properties of windblown dust and interbedded soil layers of the Chinese Loess Plateau are used to calculate rainfall for the last million years, identifying the waxing and waning of the Southeast Asian summer monsoon. Comparison of our magnetic rainfall record on land with environmental records from the deep-sea shows that summer monsoon intensity is linked with growth and decay of continental-sized ice sheets, in turn reflecting changes in the Earth's orbit around the Sun.  相似文献   

15.
Understanding the costs that climate change will exact on society is crucial to devising an appropriate policy response. One of the channels through while climate change will affect human society is through vector-borne diseases whose epidemiology is conditioned by ambient ecology. This paper introduces the literature on malaria, its cost on society, and the consequences of climate change to the physics community in hopes of inspiring synergistic research in the area of climate change and health. It then demonstrates the use of one ecological indicator of malaria suitability to provide an order-of-magnitude assessment of how climate change might affect the malaria burden. The average of Global Circulation Model end-of-century predictions implies a 47% average increase in the basic reproduction number of the disease in today’s malarious areas, significantly complicating malaria elimination efforts.  相似文献   

16.
胡永云 《物理》2022,51(1):10-15
两位气候学家和一位理论物理学家共同荣获2021年诺贝尔物理学奖。诺贝尔物理学奖委员会在背景介绍材料中指出,他们在“理解复杂物理系统领域做出了开创性贡献”。相信很多人会对两位气候学家获奖而感到惊讶,物理学奖委员会进一步具体指出,人类活动导致全球变暖这一论断建立在坚实的科学基础之上,两位气候学家获奖是因为他们基于物理原理模拟地球气候、量化气候变率、可靠地预测全球变暖所做出的杰出贡献。物理学奖委员会将诺贝尔奖授予两位气候学家,表明对基于物理理论解决现实世界复杂物理问题的高度重视,尤其是对人类身处其中的气候环境问题的重视。文章将解读两位气候学家的学术贡献,尤其是如何基于基础物理理论建立预测全球变暖的模型以及检测和归因人类活动导致全球变暖的方法。  相似文献   

17.
The cosmic-ray-driven electron-induced reaction of halogenated molecules adsorbed on ice surfaces has been proposed as a new mechanism for the formation of the polar ozone hole. Here, experimental findings of dissociative electron transfer reactions of halogenated molecules on ice surfaces in electron stimulated desorption, electron trapping and femtosecond time-resolved laser spectroscopic measurements are reviewed. This is followed by a review of the evidence from recent satellite observations of this new mechanism for the Antarctic ozone hole, and all other possible physical mechanisms are discussed. Moreover, new observations of the 11-year cyclic variations of both polar ozone loss and stratospheric cooling and the seasonal variations of CFCs and CH4 in the polar stratosphere are presented, and quantitative predictions of the Antarctic ozone hole in the future are given. Finally, a new observation of the effects of CFCs and cosmic-ray-driven ozone depletion on global climate change is also presented and discussed.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号