Английский язык = English. Учебное пособие

increased; and in addition if the large-scale introduction of radiosonde observations on these vessels could be arranged, a considerable improvement in the present upper-air network would result. But these methods alone will by no means solve the problem of sampling the atmosphere over the vast empty reaches of ocean where no ship sails.

Several new methods are fortunately available or are being studied to fill these gaps on land and sea. In the first place the meteorological satellite has already demonstrated beyond any doubt its unique and unprecedented capacity for obtaining certain types of weather information on a truly global scale. By means of television cameras and infra-red sensors cloud patterns covering the Earth can be detected and from this information much can be learned about weather systems and their movement and development. These valuable functions, which have given us the first global view of the world’s weather will certainly be extended in the future. Spectrometers and other new devices, perhaps including lasers, will enable satellites to be used for vertical sampling of temperature and other elements. It is clear that within a few years space techniques will have to play a leading role in a new observational system.

Other methods used to complete the system will include special aircraft reconnaissance flights as well as reports from commercial aircraft. The use of radiosondes which transmit observations as they descend on a parachute after release from an aircraft is likely to become more widespread. Meteorological rockets and ocean weather ships will also play their role.

Many of these projects are still experimental and the final mixture of observing techniques will evidently depend on many factors, not least the cost and efficiency of each type in different parts of the world. Whatever the choice, meteorology stands on the threshold of a new era as the result of the rapid development in space technology and advances in electronics, with the promise of considerable benefits to be reaped from the money and effort expended upon the global observing system.

But effort and money devoted to this end will be of little avail unless it is effectively supported by a speedy and reliable system for the collection and distribution of the resulting data. For this reason a telecommunication system capable of handling a greatly increased quantity of material is being developed whose task is to collect weather observations from all parts of the world, taking into account various methods used to obtain measurements, and then to ensure that they are rapidly transmitted to the national, regional and world meteorological centres which are waiting to use them. It also has a second function, hardly less important, to provide a means by which the analyses and forecasts based on the observations can be given the required distribution. Not infrequently as a part of the forecasting system the telecommunication channels must carry warnings of the approach of bad weather

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for which early device is vital to the safety of human life. The essence of the system is therefore speed and reliability.

From English for the students of Geography, part III by M.A. Vasilyeva

More About Life on Venus

The possibility of life on the surface of Venus has been given another airing, this time by the distinguished American scientist Dr. Libby, Professor of Physics at University of California, at Los Angeles. The essence of Dr. Libby’s argument is that, in spite of the high temperatures thought to be characteristic of the surface of Venus, it should nevertheless be possible for icecaps to exist there.

The conclusion is based on data obtained by the Russian spacecraft Venera-4. Measurements by Venera-4 show that the atmosphere of Venus consists largely of carbon dioxide. There seems to be as much carbon dioxide in the atmosphere of Venus as there is in the form of limestone in the earth’s crust.

This suggests that the planets may be similar in composition and history. The carbon dioxide on the Earth is believed to have been liberated by volcanic action, together with large amounts of water, presumably in the form of steam. This poses the question: what has happened to Venus’ water?

The Venera-4 measurements show that the water cannot be in the atmosphere, and there are good reasons for believing that there are no oceans on Venus. Professor Libby therefore suggests that water may be trapped in icecaps at the poles.

At first sight this seems to contradict much to what is known about Venus. Evidence based on the emission of short wavelength radiowaves, called microwaves, shows that the temperature at the surface of the planet might be as high as 400° C in equatorial regions and 200° С at the poles.

Venera 4, however, found the temperatures in the equatorial regions to be lower than this, about 200°. This suggests to Professor Libby that a temperature below the freezing point of water may be possible at the poles. The polar temperature based on the microwave data could be in error, Dr. Libby suggests, because of the great thickness of the atmosphere through which emission from the polar regions has to travel.

For similar reasons, he suspects the surface temperatures measured by the US space probe Mariner-2. In his article in the Science, Professor Libby says that our knowledge of Venus supports the idea that the Earth and Venus were made of similar material and contained about the same amount of carbon in the form of carbides, carbonates and so on. These carbon compounds were converted to carbon dioxide and released to the atmosphere in association

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