A weather map is an important tool for geographers. A succession of three of four maps presents a continuous picture of weather changes. Weather forecasts are able to determine the speed of air masses and fronts; to determine whether an individual pressure area is deepening or becoming shallow and whether a front is increasing or decreasing in intensity. They are also able to determine whether an air mass is retaining its original characteristics or taking on those of the surface over which it is moving. Thus, a most significant function of the map is to reveal a synoptic picture of conditions in the atmosphere at a given time.
All students of geography should be able to interpret a weather map accurately. Weather maps contain an enormous amount of information about weather conditions existing at the time of observation over a large geographical area. They reveal in a few minutes what otherwise would take hours to describe. The United States weather Bureau issues information about approaching storms, floods, frosts, droughts, and all climatic conditions in general. Twice a month it issues a 30-day outlook which is a rough guide to weather conditions likely to occur over broad areas of the United States. These 30-day outlooks are based upon an analysis of the upper air levels with often set the stage for the development of air masses, fronts, and storms. Considerable effort is being exerted today to achieve more accurate weather predictions. With the use of electronic instruments and earth satellites, enormous gains have taken place recently in identifying and tracking storms over regions which have but few meteorological stations. Extensive experiments are also in progress for weather modification studies. But the limitations of weather modification have prevented meteorological results except in the seeding of super-cooled, upslope mountainous winds which have produced additional orographical precipitation on the windward side of mountain ranges. Nevertheless, they have provided a clearer understanding of the fundamentals of weather elements.
1 One characteristic of weather maps not mentioned by the author in this passage is .
A wind speed
B thermal changes
C fronts
D barometric pressure
2 The thirty-day forecast is determined by examining .
A upper air levels
B satellite reports
C changing fronts
D daily air maps
3 The observation of weather conditions by satellites is advantageous because it .
A gives the scientist information not obtained readily otherwise
B enables man to alter the weather
C uses electronic instruments
D is modern
4 A weather map is synoptic because it .
A summarizes a great deal of information
B can be interpreted accurately
C appears daily
D shows changing fronts
5 At the present time, experiments are being conducted in .
A 30-day outlook
B controlling storms
C satellites
D manipulating weather
参考答案
1. B2. A3. D4. A5. D
国际英语资讯:Venezuelas Diosdado Cabello sworn in as head of national legislature
国际英语资讯:Turkeys Erdogan discusses bilateral ties, regional issues with French, Uzbek leaders by ph
体坛英语资讯:VAR helps Sweden get over South Korea
体坛英语资讯:Belgium beat Panama 3-0 in World Cup Group G match
国内英语资讯:Xinhua Headlines: China-Africa people-to-people interaction expands amid more cooperation
国内英语资讯:Cambodian PM Hun Sen meets senior Chinese official on bilateral ties
国内英语资讯:Chinas first visa center in CEE opens in Bucharest
国内英语资讯:Top legislature hears reports on legal deliberations
国际英语资讯:Over 10,700 cases of femicide unresolved in Brazil in 2017
国际英语资讯:Greek govt survives no confidence motion over Macedonia name deal
体坛英语资讯:Denmark beats Peru 1-0 in tough WC Group C clash
国内英语资讯:Chinas top legislature defines coastguard powers
国际英语资讯:Palestinians hold 13th anti-Israel Friday rally in eastern Gaza
国际英语资讯:UN chief welcomes positive steps towards peace between Eritrea, Ethiopia
国内英语资讯:Top legislature hears reports on 2017 final accounts, audit work
体坛英语资讯:World Cup: Croatia defeat Nigeria 2-0
国内英语资讯:Xinhua releases article on how Xi pushes development of Xiamen Special Economic Zone
国内英语资讯:China, Nepal pledge to enhance cooperation
体坛英语资讯:Italy beat China 3-1 in mens Volleyball Nations League
Social jet lag 社交时差
国际英语资讯:UN chief urges Security Council to act with one voice on Middle East, North Africa
国际英语资讯:French court sentences two men to prison for killing Chinese designer
国际英语资讯:Cuba, India vow to deepen economic ties
“失恋了,小哥可以给我画只小脑斧吗?”盘点外卖小哥收到过的奇葩要求
国际英语资讯:Iran to oppose Saudi Arabia proposal to increase OPEC crude output: official
国内英语资讯:Chinas top political advisor visits Uganda to promote bilateral cooperation
Are chimpanzee beds cleaner than human ones? 黑猩猩的“床”比人类的床还干净?
国际英语资讯:Brazils Supreme Court allows political satire during electoral campaign
国际英语资讯:Europe must be able to defend borders: central European states
国内英语资讯:China to calmly face fickle U.S. attitude: official
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |