Conservation of Biodiversity

Over the years, the depletion of biodiversity has been quite active. This is happening as a result of habitat loss, excessive exploitation of resources, climatic changes, diseases, pollution, poaching of animals etc. All living organisms are natural biological resources that in turn help to create conditions for life on the Earth, including human beings. Maintenance of biodiversity is of vital importance for both present and future generations. Decrease of biodiversity would result in severe ecological problems and raise moral/esthetic consequences for human populations. It can be considered as a global problem, as important as destruction of the ozone layer or increase of carbon dioxide (CO2) concentration in the atmosphere.

For the last 65 years extinction of plants and animal species has been proceeding at an elevated level. Degradation of many valuable communities has also been observed, mostly associated with the increasing impact of human activity on the biosphere.

For the last few decades, the rate of species extinction has been, on average, five times the background rate. Taking into account that the average period of existence for each species on the planet is about 4 million years, the theoretical average rate of extinction must comprise four species per year, for a total number of species of about 10 million. However, in the very near future, according even to the most modest estimates, about 50 000 species will die out each year.

Three main reasons are usually emphasized when giving arguments about the extreme importance of halting the processes of biodiversity reduction.

The first reason (or more exactly a group of reasons) is associated with the possibility of destruction of ecosystems and biospheric functions. These functions provide for optimal gas content of the atmosphere, biological purification of fresh waters, maintenance of the ability of ecosystems to transform solar energy into the chemical energy needed by living organisms, absorption of polluting substances and consequent purification of different habitats, etc. Ecologists have always connected stability of ecological systems with diversity.

The second reason to conserve biodiversity is associated with the commercial value of living organisms. Humans use plants and animals for production of food, medicine, clothes, construction materials, etc. Furthermore, the products of photosynthesis provide people with their main source of energy. Humans rely on only about thirty species of plants, in a variety of genetic forms. This number could potentially be multiplied a thousand fold by utilizing wild species of plants for food production, until their extinction.

The third reason for biodiversity conservation is moral and esthetic. In only fifty years, the human population has doubled and has now reached more than 6 billion. Homo sapiensis clearly the dominant species on the Earth. As a result of human activity one third of the forests has been destroyed, about one fourth of the soil cover has been exhausted, the ozone layer has been depleted, concentration of carbon dioxide keeps on increasing in the atmosphere, and hundreds of thousands species of living organisms have died out.

All the human commercial activity that negatively affects biodiversity or the state of biological resources, and indeed the biosphere, can be examined by taking Russia as an example. Over the last half century in Russia, the processes of biodiversity extinction have intensified at all levels (genetic, species, and ecosystem). Reduction of biological diversity has resulted in decrease of stability of terrestrial and aquatic ecosystems, and has caused negative changes to the environment and quality of human life.

While in a number of regions of Russia, these changes are irreversible, in others biological diversity can still be saved and restored.

Biodiversity conservation is basically aimed at protection, enhancement and scientific management of the biodiversity. To be precise, manage it at its threshold level and acquire sustainable benefits both for the present and future population.

Biodiversity conservation has three prime objectives:

· Maintain crucial ecological processes as well as life support systems.

· Preserve the variety of species.

· Make sustainable exploitation of ecosystems and species.

 

3. Skills development. Underline 2-3 key words in every paragraph. Headline the paragraphs. Retell the text.

 

2. Vocabulary. Match the term with its translation:

habitat loss excessive exploitation of resources climatic changes species extinction poaching of animals biological diversity depletion of ozone layer irreversible changes exhausted soil polluting substances

вымирание видов климатические изменения истощенная почва чрезмерная эксплуатация ресурсов разрушение озонового слоя необратимые перемены биологическое разнообразие браконьерство животных   утрата мест обитания загрязняющее вещество

3. Skills development. Is the statement true or false?

1. Decrease of biodiversity can result in big ecological problems.

2. Mammals is clearly the dominant species on the Earth.

3. As a result of human activity, about one fifth of the soil cover has been exhausted.

4. People can save and restore biological diversity.

5. Biodiversity conservation has a lot of prime objectives.

6. The depletion of biodiversity is a global problem.

7. About 50 000 species have died out already.

8. People carry a moral responsibility for the state of the biosphere.

 

4. Vocabulary. Complete the table.

noun	verb
	reduce
extinction
decrease
	deplete
protection
	pollute
	examine
concentration
activity
	purify

 

5. Vocabulary. Fill in the gaps with the words from the text.

1. All living organisms are natural biological ….. that in turn help to create conditions for life on the Earth.

2. For the last 65 years ….. of plants and animal species has been proceeding at an elevated level.

3. Three main reasons are usually emphasized when giving ….. about the extreme importance of ….. the processes of biodiversity reduction.

4. Ecologists have always connected stability of ecological systems with …...

5. Humans rely on only about thirty ….. of plants, in a variety of genetic forms.

6. As a result of human activity one third of the forests has been ….., about one fourth of the soil cover has been …...

7. Reduction of biological ….. has resulted in decrease of stability of terrestrial and aquatic ……

8. Biodiversity ….. is basically aimed at protection, enhancement and scientific management of the biodiversity.

6. Vocabulary. Match the word with its definition.

1. to reduce 2. to contaminate 3. to consume 4. to solve 5. to waste 6. to transport 7. to regain 8. to contain 9. to supply 10. to increase 11. to survive 12. to dispose of

a. to carry from one place to another b. to change food in the stomach c. to get back to d. to make smaller in size, make less e. to become greater or larger  f. to give or provide g. to have or hold h. to continue to live or exist i. to make dirty j. to find the answer to k. to use without a good purpose l. to get rid of

 

7. Grammar. Find gerund in the text “Conservation of Biodiversity”. Which forms of gerund do you know?

8. Grammar. Translate into Russian, pay attention to -ing forms, determine their part of speech.

1) The role of ecosystems in understanding the environmental challenges faced by humankind has grown significantly.

2) Although household hazardous waste is only a small part of municipal solid waste, it can pose problems such as catching on fire, or injuring the skin or eyes of workers coming in contact with it, or breathing its fumes.

3) Following a review of the historical development and refinement of the ecosystem concept, the authors explain how ecosystems function through analysis of the complex interactions between life and its physical environment.

4) Large quantities of packaging are generated: its composition may make it difficult to recycle, or prevent it from biodegrading.

5) The increasing value of the ecosystem concept is demonstrated through its applications.

6) The amount American communities pay for waste management is second or third only to spending on education and police protection.

7) The Gaia hypothesis was developed by James Lovelock in 1979. Having made a high scientific reputation, and achieved financial independence through his development of the electron capture detector, a key device in environmental analysis, he turned his attention to a unified view of earth and life sciences.

8) Treatment serves two purposes, either reducing waste volume or reducing its toxicity.

9) Most plant species are intermediate, having a combination of traits to resist environmental pressures producing stress, or disturbance, and to forage for their required resources in the face of competition from other plants.

10) While maintaining container strength, manufacturers from the late 1970s to 1993 reduced the weight of plastic soda bottles by 25%, the weight of glass bottles 31%, and of aluminum containers even more.

11) This means that water in the soil is vital for the nutrition of terrestrial plants, as well as having an equally vital role as an input to photosynthesis.

12) Another means to reduce food wastage is to eliminate trays in school and college cafeterias: this leads to students taking less food.

13) By protecting the Catskills’ from pollution and recognizing the natural water filtration capability of undeveloped land, the City avoided having to build a $6 billion treatment plant to purify its drinking water, plus the $300 million a year it would have cost to run the plant.

14) Environmentally preferable products are those that have been analyzed and selected on the basis of having lesser impacts on human health and the environment as compared to others that serve the same purpose.

15) For many years, a Bhopal court had criminal charges pending against Union Carbide’s then Chief Executive Officer, accusing him of having consciously decided to cut back on safety and alarm systems as cost-cutting measures.

16) Although expert opinion differs, most agree that we are uncomfortably close to having used half the world’s oil.

17) And recycling facilities suffer the same resistance to having them in the neighborhood as do landfills and incinerators, the not-in-my-backyard, or NIMBY, phenomenon.

18) Joseph Romm’s book, Cool Companies notes that companies – even after having already gone through a careful examination of energy-saving opportunities – can repeat the process and find additional ways to conserve energy.

19) At one point, when he entered a field not posted as having been recently treated with organophosphate pesticide, he became very ill with sweating, trembling, and tunnel vision.

20) Despite many different materials having been proposed as biomass feedstock for biochar (including wood, crop residues and manures), the suitability of each feedstock for such an application is dependent on a number of chemical, physical, environmental, as well as economic and logistical factors.

METEOROLOGY

UNIT 11

Atmospheric Processes and the Weather. Weather Forecast

 

1. Introduction. Discuss the questions.

Where does the word “meteorology” come from?

Why is meteorology important to study?

What are the different branches of meteorology?

What are the basic instruments of meteorology?

What should you study at university to get a job in meteorology?

Can a meteorology graduate work at NASA?

 

2. Vocabulary. Read the descriptions of the weather and the climate. Can you now explain the saying “ Climate is what you expect, weather is what you get.” Then fill in the Comparison chart under the text with the phrases below.

 

 

 

Weather is a day-to-day state of the atmosphere, and its short-term variation during periods varying from minutes to weeks. People generally think of weather as the combination of temperature, humidity, precipitation, cloudiness, visibility, and wind. We talk about changes in weather in terms of the near future: "How hot is it right now?" "What will it be like today?" and "Will we get a snowstorm this week?"

Climate is the weather of a place averaged over a period of time, often 30 years. Climate information includes the statistical weather information that tells us about the normal weather, as well as the range of weather extremes for a location.

Comparison Chart

BASIS FOR COMPARISON	WEATHER	CLIMATE
Meaning
What is it?
Represents
Variation
Affected by
Assessment
Studied by

 

average state of atmosphere in a region; Climatology; does not vary constantly; over a long period; everyday atmospheric condition of a particular region, as regards temperature, humidity, wind speed, etc.; temperature and precipitation; mountain ranges, attitudes, large water bodies; for short term;

minute by minute state of atmosphere in an area; the conditions of atmosphere in a geographical location, over short period; in what way atmosphere acts over typically long period; Meterology; varies constantly; temperature, humidity, air pressure, cloudiness, precipitation etc.; alludes to standard pattern of weather of a particular place, taken over more than 30 years.

3. Speaking. Discuss the following questions before reading the text:

1) Is there any difference between the terms “to predict” and “to forecast” (if necessary check the dictionary)?

2) What are the main industries affected by the weather?

3) Which atmospheric processes interact to produce the weather?

 

4. Reading. Put the paragraphs of the text in the correct order.

The weather

a) Improved scientific understanding of how the atmosphere, ocean, land and water cycles interact to produce the weather makes it increasingly possible to address the impacts of climate – defined as the average weather over a 30-year period – on people and economies. Meteorologists and climate scientists are starting to make seasonal and longer-term forecasts and to blur the boundaries between weather and climate prediction by developing “seamless weather and climate forecasts”. Climate services that draw on these forecasts will become all the more essential as human-induced climate change affects weather patterns and extreme events over the coming decades.

b) Agriculture, civil aviation and shipping, and many types of business, also depend heavily on modern weather monitoring and prediction. With access to reliable forecasts, farmers can adapt their schedules for planting, harvesting and other activities as needed. Transport is highly vulnerable to wind and storm conditions, which is why many weather stations are based at airports. Construction, energy, tourism and many other industries are also strongly affected by weather conditions.

c) We all talk about the weather, make our daily plans based on forecasts and complain when bad weather spoils our weekend. The weather does much more than determine how people dress or how they can enjoy themselves outdoors. Weather can be dangerous, causing floods, storms and heat waves that can kill or injure. Individuals and communities need to remain alert to weather conditions and forecasts in order to protect their lives and property.

Source: https://public.wmo.int/en/resources/library/career-meteorology

 

5. Vocabulary. Match the phrases from the text with their definition and translation.

 

I. to remain alert (to) II. weather condition III. civil aviation IV. weather monitoring V. weather station VI. weather forecast VII. improved understanding VIII. to address IX. climate service X. to draw on XI. weather pattern XII. extreme events

1. a greater level of understanding; 2. a place where instruments record information about the weather; 3. a report on likely weather conditions for a period of time in the future; 4. a series of weather conditions or events that together show how things normally happen; 5. one of two major categories of flying, representing all non-military aviation, both private and commercial; 6. the complex of meteorological characteristics in a given region; 7. the periodic or continuous surveillance or analysis of the state of the atmosphere and climate, including variables such as temperature, moisture, wind velocity and barometric pressure; 8. the system provided by a government or official organization for the needs of the public on climate issues; 9. to pay attention to what is happening and ready to react quickly if necessary; 10. to try to deal with the problem or question, for example by thinking carefully about it, or by doing things to improve a situation; 11. to use something that you have gradually gained or saved 12. unexpected, unusual, unpredictable, severe or unseasonal weather;

a) сохранять бдительность; b) метеоусловия, погодные условия; c) метеорологическая станция; d) климатологическая служба; e) мониторинг погоды; f) заниматься решением проблемы; g) тип (модель) погоды; h) экстремальные погодные явления; i) гражданская авиация; j) прогноз погоды; k) более глубокое понимание; l) основываться, использовать в качестве источника

 

6. Vocabulary. Paste the words given below into the gaps.

 

Observing the weather

Accurate observations about the current weather are the basis of a good weather ________. This information is also required to monitor the ________. _______ sources of observations are observing stations on land and at sea and upper-air soundings. Today, satellites, radar and aircraft are an increasingly _______ source of information.

There are many different instruments at an _______. Some measure temperature and humidity. _______ measure air pressure, wind speed and direction, rainfall and sunshine duration.

Weather Services of maritime countries make ________ with ships to take observations at sea and transmit them to shore. The observations are usually ________ free of charge by shipping companies in return for the instrumentation and the forecasting and warning service.

Upper-air soundings are obtained by _______ a balloon that carries instruments through the atmosphere. Information about pressure, temperature, humidity and wind is sent back to a _______.

Wind and other useful atmospheric information is also deduced from satellite data. Satellite meteorologists _______ the processes for turning the vast amount of data into useful information and products.

The improved _______ of weather forecasts over the last 30 years is partly due to the increase in the amount of satellite data available, along with advances made in extracting useful information for use in computer models.

Radar meteorologists have developed _______ for obtaining information about rainfall and wind from radar signals. This information shows the distribution and intensity of the rainfall and is used to forecast _______. Forecasters depend upon information from satellites to help _______ the location and development of weather systems, especially over the oceans. In addition, radar products provide forecasters with _______ information about the structure of rainfall. A _______ of satellite and radar images helps forecasters make detailed predictions of the weather over the next six hours or so. Such techniques are especially useful for providing warnings of _______ rainfall.

Source: https://public.wmo.int/en/resources/library/career-meteorology

Words to insert: accuracy, identify, others, tornadoes, ground station, provided, vital, arrangements, releasing, series, detailed, climate, observing site, forecast, techniques, heavy, traditional, develop

 

7. Vocabulary. Fill in the table according to the text above.

 

The objects of observation (the weather parameters)	Sources of observation
- - …	- - …

 

8. Word formation. Complete the table. Mark the word stress.

 

verb	noun	adjective/participle	profession
	observation
			forecaster
to monitor
		informational
to develop
	prediction
		useful
	distribution
			sounder
to rain

9. Skills development. Speaking. Make five questions to the text above and ask your partner. Take turns.

10. Reading. Read the text and decide which title suits best.

1) Steps to make a reliable weather forecast

2) Using computers to forecast the weather

3) The increasing power of computers

 

The behaviour of the atmosphere is simulated using computer models which make a detailed analysis of the state of the atmosphere at a particular time, using the latest available observations, and then apply the laws of physics to forecast what will occur.

Most computer models use a three-dimensional grid to represent the atmosphere. At each grid point, information is recorded about pressure, temperature, humidity and wind.

The starting point for making a forecast is to collect observations from around the world using the WMO Information System, which transmits surface observations, as well as data from satellites, radar and aircraft. Once the observations have been checked, they are used to determine the atmospheric variables at each grid point at the start of the forecast.

Some of the complex processes taking place in the atmosphere cannot be fully describedand represented precisely in the models so their effects have to be estimated. This is called “parameterization”. Research meteorologists use field experiments and physical principles to understand these processes and then develop the parameterization schemes.

The numerical models use the initial grid-point values, laws of physics regarding the behaviour of fluids and parameterization schemes to make a prediction of the change in grid-point values a short time ahead. New grid-point values are then calculated and the process is repeated. In this way, a forecast is built up.

With powerful computers becoming more widely available, the models are being improved constantly, allowing the behaviour of the atmosphere to be better modelled and resulting in ever-increasing accuracy of the forecasts. More and more data are being used in the modelling of the atmosphere as soon as they are collected (this is what is called “real time”). New modelling methods are also being used to improve the estimates of the confidence we should have in the forecasts.

Today, predictions made by computer models include a wide range of geographical coverage and timescales. Some models can predict weather conditions with great detail in the short range, i.e. two to three days into the future, while others can predict general weather patterns several seasons ahead.

The increasing power of computers is allowing meteorologists to benefit from multiple runs of atmospheric models to create ensemble forecasts (based on a group of forecasts) or probabilistic forecasts (e.g. there is a 30 per cent chance of rain). This is useful because sometimes small changes in initial conditions can lead to big differences in the resulting forecast.

Source: https://public.wmo.int/en/resources/library/career-meteorology

11. Grammar. Find Passive tenses in the text and fill in the table.

Present Simple	Present Continuous	Present Perfect
- - …	- - …	- - …

 

12. Grammar. Make the sentences from the exercise above active. Where necessary insert the subject of the sentence.

Ex.: The behaviour of the atmosphere is simulated using computer models. Using computer models a meteorologist simulates the behaviour of the atmosphere.

13. Grammar. Translate the sentences into English.

a) В прошлом году большая часть опасных условий для автомобильного движения и железнодорожного сообщения были вызваны туманами, метелями, ливнями, сильными ветрами и гололедицами.

b) Экстремальные погодные условия, стихийные бедствия, неспособность к адаптации к изменению климата и смягчению его последствий, а также кризис водоснабжения в последние годы признаются Всемирным экономическим форумом в качестве четырех наибольших и самых вероятных глобальных рисков для человечества.

с) Большая часть выбросов галогенированных короткоживущих субстанций (Halogenated very short-lived substances, HVSLs) будет разрушаться в тропосфере, ограничивая долю выбросов, достигающих стратосферы и вызывающих истощение озонового слоя.

d) До сих пор не установлено устойчивой связи между истощением стратосферного озона и долгосрочными изменениями приземного климата в северном полушарии.

e) Моделирование показывает, что уже к 2019 году Монреальский протокол и его поправки и корректировки принесли существенное положительное воздействие (benefits) на озон.

14. Grammar. Insert the correct verb.

1. Changes in tropospheric circulation driven by ozone depletion ___________ to recent trends in Southern Ocean temperature and circulation

a) have contributed b) has been contributed               c) is contributing

2. Increases in greenhouse gas concentrations ________ to lead to increases in upper-stratospheric ozone at all latitudes, with a more complex pattern of ozone changes in the lower stratosphere.

a) will predict b) predict        c) are predicted

3. Despite these persistent model uncertainties, significant advances ___________ in the understanding of processes responsible for the modeled ocean and sea ice response to ozone depletion.

a) have been made    b) have made            c) made

4. In the lower stratosphere, observed global mean cooling ____ largely ______ to stratospheric ozone changes over the past few decades.

a) is attributed          b) will be attributed c) was attributed

5. Understanding the extratropical rainfall response __________ by the quality of observational products, with little in situ data and changes in satellite products leading to substantial differences across reanalysis results.

a) is hampered         b) hampers               c) is hampering

15. Skills development. Give the summary of the text above using the following word combinations.

to be simulated, a detailed analysis, a three-dimensional grid, to be recorded, the starting point for, the WMO Information System, to be checked, parameterization, the numerical models, to be improved, to improve the estimates of the confidence, a wide range of, to benefit from, ensemble forecasts.

 

16. Speaking. Prepare to speak about the difference of the weather and climate, the methods of observing the natural phenomena and the forecasting of the weather using computer models. Work one by one to make a complete story (the first student says the first sentence, the next one should continue the idea, and so on).

 

17. Vocabulary. Match the verbs in column A with the nouns in column B to make phrases.

A	B
to apply to build up to collect to develop to lead to to make to model/to simulate to predict to result in	a detailed analysis observations weather conditions the laws of physics a forecast big differences ever-increasing forecast accuracy the behaviour of the atmosphere the parameterization schemes

 

18. Vocabulary. Solve a meteorological crossword puzzle.

 

									7
		8
9
						2							4
				1
				3
									6
										5
											10

 

1. The process by which the air obtains the maximum amount of water vapour that is possible at the given temperature and pressure

2. A part of the atmosphere which has relatively uniform temperature and pressure.

3. An amount that is calculated by adding several numbers together and dividing the total by the original number of things that you added together.

4. The process in which air, being warmed close to the ground, rises.

5. Area of high atmospheric pressure that has a characteristic pattern of air circulation, with subsiding air and horizontal divergence of the air near the surface in its central region.

6. To predict weather conditions on the basis of correlated meteorological observations.

7. Air surrounding the Earth.

8. The degree or intensity of heat present in a substance or object, especially as expressed according to a comparative scale and shown by a thermometer or perceived by touch.

9. Enclosed area of low pressure revealed by the pattern of pressure distribution.

10. Water or other liquid diffused in a small quantity as vapour, within a solid, or condensed on a surface.

 

Choose from the following words:

moisture, atmosphere, anticyclone, saturation, mean, depression, forecast, convection, layer, temperature

19. Reading. Read the text. Prepare to answer the following questions:

1) What does the air contain that stimulates formation of condensation nuclei?

2) Why do the clouds have so many various forms?

3) Which level marks the base of a cloud?

4) Why does the convection happen?

5) How do the wave clouds form?

6) What is the main parameter for dividing cloud types?

 

Cloudforming processes

When water in the atmosphere condenses, it first becomes visible as a cloud, if it is at some upper level, or a fog, if it rests on the ground. Clouds consist of minute water droplets, so small that they float in the air and are carried about by the air currents. If the air were absolutely clean and pure, the water vapour, on cooling, would not readily condense into droplets of visible size. But in fact the air is full of minute particles of dust, smoke and salt from sea spray, sometimes thousands of them in a cubic inch. They stimulate the formation of ice crystals and water droplets around them and are called condensation nuclei.

Clouds have a great variety of forms, from the towering thundercloud to the flat gray pall of a dull winter day. These forms arise from the different processes of cooling by which the vapour is condensed.

The main process of cooling is decompression or expansion arising from the upward movement of air. When this movement occurs in an unstable atmosphere, the air rises in large bubbles or columns. At a given height that depends on the original temperature and humidity of the rising air, condensation begins; this level marks the base of the cloud. The top of the rising column is marked by bulging cauliflower-like heads, which continue to rise until they reach a stable layer. The process is called convection, and the type of cloud, from its heaped appearance, is known as cumulus. There are usually clear spaces between such clouds, and by day the formations appear brilliancy white from the sun shining on their tops and sides. Their flat bases and shady sides are usually gray.

Vertical motion in the atmosphere is also generated by turbulence, the constant stirring of the air caused by wind and gustiness. The air goes up and down not in large bubbles but in small filaments or cores, jumbled together. The result is not a few detached clouds but a more or less continuous layer. If there is a stable layer at some upper level the vertical motion is checked, and the air spreads out horizontally, increasing the tendency for the clouds to fuse together into a sheet.

When the terrain cools, low-level air masses also lose temperature. Such cooling gives rise to a layer of stratus cloud. For this reason, stratus clouds tend to increase by night and diminish by day. Convection clouds, however, which require surface heat for their formation, tend to build up by day and disappear at night.

When the wind blows across a range of hills, a wave-like motion of air is sometimes set up on the downstream side of the hills. In the crests of the waves air moves upward, and it may be cooled enough for clouds to form; in the troughs the air warms up and the clouds are evaporated. These clouds tend to remain in the same position relative to the hills and are called wave clouds.

Clouds are commonly grouped into physical forms that can be up to five in number: cirriform, cumuliform, cumulonimbiform, stratocumuliform, and stratiform. These designations distinguish a cloud's physical structure and process of formation.

 

20. Vocabulary. Match the phrases with the type of their formation. Use the dictionary if necessary.

minute droplet, float, are carried about, condensation nuclei, arise from, unstable atmosphere, rising column, consist of, bulging head, heaped appearance, detached clouds, constant stirring, stratus cloud, jumbled filaments, to fuse together, gives rise to, wave-like motion, the downstream side, towering thundercloud, gray pall, given height, convection cloud.

adj. + n. (part. + n.)	n. + n.	v. + prep.
- - …	- - …	- - …

 

21. Vocabulary. Insert the expressions from the text above in the table. Find the adjectives/participles describing the appearance of the listed clouds and the processes giving rise to their formation.

 

cloud type	appearance	conditions of formation
cumulus	- - …
stratus cloud
wave clouds

 

22. Reading. Read the article. Prepare to answer the following questions:

1. When does condensation/evaporation take place?

2. What does the latent heat mean?

3. What does the rate of vaporizing depend on?

4. What is the main idea of each paragraph of the text? Give the name to each paragraph.

Condensation and evaporation

Condensation, the direct cause of all the various forms of precipitation, occurs under varying conditions which in one way or another are associated with change in one of the linked parameters of air volume, temperature, pressure or humidity. Thus, condensation takes place when the temperature of the air is reduced but its volume remains constant and the air is cooled to dew point; if the volume of the air is increased without addition of heat; this cooling takes place because adiabatic expansion causes energy to be consumed through work, or when a joint change of temperature and volume reduces the moisture-holding capacity of the air below its existing moisture content. The key to the understanding of condensation clearly lies in the fine balance existing between these variables. Whenever the balance between one or more of them is distributed beyond a certain limit condensation may result.

The most common circumstances for condensation producing are those producing a drop in air temperature; namely contact cooling, mixing of air masses of different temperatures and dynamic cooling of the atmosphere. Contact cooling is produced, for example, within warm, moist air passing over a cold land surface. On a clear winter night strong radiation will cool the surface very quickly and this surface cooling will gradually extend to the moist lower air, reducing the temperature to a point where condensation occurs in the form of dew, fog or frost, depending on the amount of moisture involved, the thickness of the cooling air layer and the dew-point value. The latter being below 0° C, it is referred to as the hoar frost-point if the air is saturated with respect to ice. The mixing of the differing layers within a single air mass or of two differing air masses can also produce condensation. Undoubtedly the most effective cause of condensation, however, is the dynamic process of adiabatic cooling.

It’s worth noting that evaporation occurs whenever energy is transported to an evaporating surface if the vapour pressure in the air is below the saturated value. The saturation vapour pressure increases with temperature. The change in state from liquid to vapour requires energy to be expended in overcoming the intermolecular attraction of the water particles. This energy is generally provided by removing heat from the immediate surroundings causing an apparent heat loss (latent heat), and a consequent drop in temperature. The latent heat of vaporization to evaporate 1 g of water at 0° С is 600 calories. Conversely, condensation releases this heat, and the temperature of an air mass in which condensation is occurring is increased as the water vapour reverts to the liquid late. The diurnal range of temperature is often moderated by damp air condition, when evaporation takes place during the day and condensation at night.

Viewed another way, evaporation implies an addition of kinetic energy of individual water molecules and, as their velocity increases, so the chance of individual surface molecules escaping into the atmosphere becomes greater. As the faster molecules will generally be the first to escape, so the average energy (and therefore temperature) of those composing the remaining liquid will decrease and the quantities of energy required for their continued release become correspondingly greater. In this way evaporation decreases the temperature of the remaining liquid by an amount proportional to the latent heat of evaporation.

The rate of vaporizing depends on a number of factors. The two most important are the difference between the saturation vapour pressure at the water surface and the vapour pressure of the air, and the existence of a continual supply of energy to the surface. Wind velocity can also affect the evaporation rate because the wind is generally associated with the importation of fresh, unsaturated air which will absorb the available moisture.

23. Vocabulary. Match the suitable words from column A and B to form word combinations.

 

A	B
wind moisture-holding latent dynamic hoar moisture water adiabatic kinetic dew intermolecular unsaturated heat	energy molecules capacity attraction content air loss velocity expansion cooling point heat frost-point

 

24. Vocabulary. Try to explain the following words and word combinations in English.

contact cooling, to be worth noting, evaporation rate, to be generally associated with, unsaturated air, the key to the understanding, viewed another way, most common circumstances, to be referred to, adiabatic cooling, namely, diurnal range, to be expended.

 

25. Vocabulary. Cross out an odd word in each line. Number each line according to the headings given below.

 

adiabatic cooling contact cooling air masses mixing              wind pattern

joint                correspondingly diurnal                     moist

radiation         adiabatic         contact                     condensation

wind velocity  energy supply saturation vapour pressure latent heat

clean               rate                 cause                        vapour

 

Headings: 1) Types of cooling; 2) Factors of vaporizing rate; 3) Adjectives; 4) Causes of condensation; 5) Conversion-derived words.

 

Unit 12