一、初中英语作文沙尘暴是怎样形成的

沙尘暴的形成需具备4个条件.

一是地面上的沙尘物质.它是形成沙尘暴的物质基础.

二是大风.这是沙尘暴形成的动力基础,也是沙尘暴能够长距离输送的动力保证.

三是不稳定的空气状态.这是重要的局地热力条件.沙尘暴多发生于午后傍晚说明了局地热力条件的重要性.

四是干旱的气候环境.沙尘暴多发生于北方的春季,而且降雨后一段时间内不会发生沙尘暴是很好的证据.

春季沙漠的边缘地区,由于长期干旱,而且地表少有植被覆盖,当有大风来临的时候地表的沙尘很容易被吹起且被输移,但由于沙子粒径较大,不易形成悬移(悬浮移动,是小颗粒物质保证长距离输移的必要条件),因此不能长距离输移,这也是距沙尘较远的地区只有降尘而少见扬沙的主要原因.如果风持续的时间很长,形成悬移的浮尘能够被输送到很远的地方,所经过的地区就会出现沙尘暴；当风速减弱到一定程度后,浮尘就会降落,该地就会出现降尘天气.如果此时降水,就会形成所谓的“泥雨”.

从沙尘暴形成过程所需的4个条件看,黄土高原、广袤的沙漠及由人为因素的破坏正处于荒漠化过程中的土地,北方春季末耕种的土地及处于施工过程中的基础设施(如高速公路等)为沙尘暴的发生提供了充分的物质源；而春季北方地区的干旱,又使沙尘暴发生的可能性增强；大风的产生是一种复杂的大气现象,主要是冷锋活动或经纬向环流调整作用的结果.由此可见沙尘暴的产生是多种复杂因素共同作用结果,人类活动对自然界的破坏导致土地荒漠化的加剧,对沙尘暴发生产生了极其重要的作用,而近几年全球干旱(其原因目前尚未知)等异常天气现象也对沙尘暴的发生起了不可估量的作用.所以说人类活动对沙尘暴的产生只起到一定作用,并不能说沙尘暴就是人为因素造成的.

The formation of the sandstorm to have the four conditions.

One is the dust on the ground material.It is the material basis of form sandstorm.

2 it is winds.This is the power of the formation,is fundamental to the power of the sandstorm long-distance transport of guarantee.

Three is not stable air condition.This is an important local thermal conditions.Sandstorm occurs more often in the afternoon that incorporates the evening the importance of thermal condition.

Four is the dry weather environment.Born in the north of the sandstorm multiple spring,and rain after a period of time within a won't happen very good evidence is dust storms.

The edge of the desert in the spring,due to long drought,and surface vegetation cover,when there is little wind comes on the surface of the earth is easy to be blowing dust and sand,but due to lose move large particle size,is formed not easily movable (suspension movement,it is small particle material guarantee to lose the necessary conditions of long distance move),and therefore can not move long lost,this is far from the dust in the dust and rare only micrometeorology main reason.If the wind last time is very long,form the dust suspended loads can be transported to a very far place,through which areas will appear sandstorm; When the winds weaken to certain degree,floating dust will the landing,the dust weather will appear.If the precipitation,can form the so-called "NiYu".

The formation process from the four conditions look,the loess plateau and vast desert and by the destruction of the human factors in the process of desertification is in the land of the north,at the end of the spring farming land and in the construction process of infrastructure (such as high speed road,etc.) for the dust storm occurrence providing full source material; And the spring drought in the north,and the likelihood of the sandstorm strengthened; The winds generated is a complex phenomenon,mainly is the cold air activities or to the circulation of the regulatory role longitude results.This shows the generation of sandstorm is DuoZhong complex factors results of human activity on the natural world to disruption of the desertification intensifies,dust storms happen to have an important role,and in recent years the global drought (the cause isn't yet known) abnormal weather phenomenon also to the dust storm occurrence have played an important role.So that human activities for the generation of dust storms only play a role,and can't say dust storms are caused by human factors.

二、求一篇关于沙尘暴的英语文章，要多一些介绍原因，特点，措施，总之越全面越好，最好有翻译

At first glance, dust storms do not seem very fascinating. Winds pick up fine particles from the ground, and then the air becomes thick with dust. What is interesting, though, is that dust storms can travel across the ocean, sometimes from continent to continent. Such dust storms are worth investigating.

In April of this year, a dust storm that originated in China and Mongolia took a six-day journey across more than ten thousand kilometers of sea and open land to Arizona in the United States. The cloud was so dense that it seemed as if the sun were setting early. At least one person thought a volcano had erupted.

Although traveling dust storms are nothing new, the dust now often contains chemical or metallic substances that contribute to respiratory illnesses and damage the environment. At present, a group of researchers in Asia is studying aerosol particles and their effects on the environment—and they have plenty of dust to work with.

Dust storms are one of the repercussions of humans messing around with Mother Nature. Although they are a natural phenomenon, dust storms have been occurring more often, at shorter intervals, and with greater force in recent years, and human activity is the cause.

It is a fact that excessive herding of animals and exploitation of grasslands are responsible for the majority of dust storms. This means that dust storms are largely a result of human actions; in other words, they are controllable.

We seem to think, however, that economic development and preservation of the environment cannot go hand in hand. For most countries, economic development comes first, at the expense of the environment. It is high time everyone came to grips with the consequences of overusing the earth's resources, including the misuse of land in the pursuit of economic wealth.

乍看之下，沙尘暴似乎不怎么引人注意。地面的细沙被风卷起，空气中便充满厚厚的灰尘。但有趣的是，沙尘暴能穿洋渡海，有时还能横越大洲。这样的沙尘暴值得我们去好好研究一下。

今年四月，源自中国大陆及蒙古内陆的沙尘暴，在六天中跨越了一万多公里的海洋与空旷陆地，最后到达美国亚利桑那州。阴云密布，就象太阳将提早要下山，有人居然以为是火山爆发了。

虽然移动的沙尘暴没什么稀奇，但现在那些沙尘通常含有引起呼吸道疾病和破坏环境的化学或金属物质。现在亚洲有一批研究人员正在研究悬浮颗粒及其对环境的影响——他们要研究的沙尘可多着呢!

沙尘暴就是人类任意破坏大自然，所造成的影响之一。沙尘暴虽是自然现象，但是近年来发生的频率却逐渐增加，间隔的时间也愈来愈短，破坏力更强大了，人的活动是罪魁祸首。

事实上，沙尘暴形成的主要原因是过度放牧及滥垦草原，这表明沙尘暴大多是人的活动所导致，也就是说，它们是可加以控制的。

不过，我们似乎认为经济发展与环境保护无法同时兼顾。对大部分国家来说，经济发展是第一位的，为此可以不惜牺牲环境。然而，我们已过度使用了地球的资源，包括为了追求经济繁荣而滥用的土地，如今该是我们认真面对这个后果的时候了。

三、沙尘暴形成原因英文版

Sand-dust storm is a weather event mainly occurred in the arid and semi-arid regions of the world, which is caused by the sand and dust blown into the atmosphere by strong wind. After its occurrence, the atmosphere becomes very dusty and the sight distance in the horizontal direction is less than 1000m. Sand-dust storm is also a natural event that can cause serious disaster and soil erosion. Consequently, sand-dust storm can be a indicator of the degree of desertification.

The occurrence of sand-dust storm is mainly controlled by atmosphere circle, weather condition, and characteristics of land cover. However, after its occurrence, human being can do nothing to it. To reduce its occurrence frequency and the possible caused disasters, the only practicable way is to improve the condition of land cover. Therefore, researches focus on the relationship between land cover and sand-dust storm can not only reveal the occurrence mechanism of sand storm but also provide the theoretical basis to control it. Besides, these researches can also provide theoretical basis for the actions to improve the eco-environment in Northwest China.

四、以“Sandstorms”为题写一篇100字左右的英语文章，主要介绍沙尘暴的定义、成因、危害和预防措施等

A sandstorm is exactly what it sounds like; a very strong windstorm, especially in the desert, that carries clouds of sand or dust, and greatly reduces visibility. These are also known as dust storms. This wind is usually caused by convection currents (which are created by intense heating of the ground), and is usually strong enough to move entire sand dunes. Air is unstable when heated, and this instability in the air will cause the mixture of higher winds in the troposphere with winds in the lower atmosphere, producing strong surface winds. Sandstorms can interfere with travel, and sometimes obliterates entire roads, and dry, flat regions, such as parts of the western United Sates. They can be seen as solid walls of sand that are up to 5,000ft high. Similar dust storms from windborne particles can be found on the planet Mars, and are thought to be seasonal.