Changes in the temperature of the surface air layer during the day and year are due to periodic fluctuations in the temperature of the underlying surface and are most clearly expressed in its lower layers.
In the diurnal course, the curve has one maximum and one minimum. The minimum temperature is observed before sunrise. Then it rises continuously, reaching the highest values at 14 ... 15 h, after which it begins to decline until the sunrise.
The amplitude of temperature fluctuations is an important characteristic of weather and climate, depending on a number of conditions.
The amplitude of daily fluctuations in air temperature depends on weather conditions. In clear weather, the amplitude is greater than in cloudy, since clouds trap solar radiation during the day and reduce the loss of heat by the earth's surface by radiation at night.
The amplitude also depends on the season. In the winter months, with a low solar altitude in mid-latitudes, it drops to 2 ... 3 ° С.
The relief has a great influence on the daily variation of air temperature: on convex relief forms (on the tops and on the slopes of mountains and hills), the amplitude of daily fluctuations is less, and in concave ones (hollows, valleys, hollows) it is greater than in flat terrain.
The purpose of the amplitude is also influenced by the physical properties of the soil:
the greater the daily variation on the very surface of the soil, the greater the daily amplitude of the air temperature above it.
The vegetation cover reduces the amplitude of daily fluctuations in air temperature among plants, since it traps solar radiation during the day, and terrestrial radiation at night. The forest decreases the daily amplitudes especially noticeably.
The characteristic of the annual variation of air temperature is the amplitude of annual fluctuations in air temperature. It represents the difference between the average monthly air temperatures of the warmest and coldest months of the year.
The annual variation in air temperature in different geographic areas differs depending on latitude and continental location. According to the average long-term amplitude and the time of the onset of extreme temperatures, four types of annual air temperature variations are distinguished.
Equatorial type. In the equatorial zone, two weakly expressed temperature maximums are observed in the year - after the spring (03.21) and autumn (09.23) equinox, when the Sun is at its zenith, and two minima - after the winter (12.22) and summer (06.22) solstices, when the Sun is at its lowest height.
Tropical type. In tropical latitudes, a simple annual air temperature variation is observed with a maximum after the summer and minimum after the winter solstice.
Temperate belt type. The minimum and maximum temperatures are observed after the solstices.
Polar type. Due to the polar night, the temperature minimum in the annual cycle is shifted by the time the Sun appears above. The maximum temperature in the Northern Hemisphere is observed in July.
The annual variation of air temperature is also influenced by the altitude of a place above sea level. With increasing altitude, the annual amplitude decreases.
AIR TEMPERATURE AND HUMIDITY
Carnation- the most sensitive plant to temperature levels. The optimum temperature in the greenhouse largely determines the size of the crop and the quality of flower products. As a general characteristic of the crop, it can be argued that carnations do not like high temperatures, therefore, when growing in summer, it is necessary to carefully control the climate in the greenhouse. It is important when the temperature rises in hot months to immediately increase the humidity above 70%. It is recommended to set the temperature for carnations in the greenhouse from 15 ° С at night and up to 25 ° С during the day. The temperature should be even, do not allow sudden fluctuations. In the middle of winter, during the period of short and especially cold days, the optimum temperature (if no additional lighting is used) during the day and night. is the range from 8 ° C to 10 ° C. Temperature drop - not allowed. But you should take into account the danger of the appearance of the Botrytis fungus (do not allow humidity to rise above 80% at such low temperatures). When growing in winter, a subsoil heating system is required. When using a ventilation system, prevent sudden rises in relative humidity.
For chrysanthemums. Constant and high relative air humidity of about 85% or more, especially during the flowering period, causes severe damage to plants with gray mold, powdery mildew, septoria, can completely destroy the crop or significantly reduce its quality. This is especially true when using film greenhouses. Therefore, during the growth period, the relative humidity of the air is maintained at 70-75%, and from the beginning of budding - 60-65%. If necessary, greenhouses are equipped with a forced ventilation system, for which they use various electric heaters. Special care should be taken to prevent dew from forming on the plants at night.
For tulips. For the formation of a flower bud, the optimal storage conditions for the bulbs will be a temperature regime in the range of 17-20 degrees with a relative humidity of 70-75%. Violation of the temperature regime for a long time will lead to a delayed formation of flower buds and inferiority of tulips.
For daffodils. In the flower greenhouse, it is recommended to maintain the optimum relative humidity. It should be between 70 and 85%
14. Evaporation from the surface of water, soil and plants
The amount of evaporation of water from the surface of the soil and plants is called the total evaporation. The total evaporation of agricultural fields is also due to the thickness of the vegetation cover, biological characteristics of plants, the depth of the root layer, agrotechnical methods of plant cultivation, etc.
Evaporation is directly measured by evaporators or calculated using heat and water balance equations, as well as other theoretical and experimental formulas.
In practice, it is usually characterized by the thickness of the evaporated layer, water, expressed in millimeters.
Evaporation tanks with an area of 20 and 100 m2, as well as evaporators with a surface area of 3000 cm2, are used to measure evaporation from a water surface. Evaporation in such pools and evaporators is determined by the change in water level taking into account precipitation.
Evaporation from the soil surface is measured with a soil evaporator with an evaporating surface area of 500 cm2 (Figure 5.10). This evaporator consists of two metal cylinders. The outer one is set in the soil to a depth of 53 cm. The inner cylinder contains a soil monolith with undisturbed soil structure and vegetation. The height of the monolith is 50 cm. The bottom of the inner cylinder has holes through which excess water from the rains falls into the catchment vessel. To determine evaporation, the inner cylinder with the soil monolith is removed from the outer cylinder every five days and weighed.
Soil evaporator GGI-500-50 1 - inner cylinder; 2 - outer cylinder; 3 - catchment. The coefficient 0.02 is used to convert weight units (g) to linear (mm). The measurement of evaporation by the soil evaporator is carried out only in the warm season. Example 3 Determine the evaporation according to observations: on August 1, the monolith weighed 42450g on August 6, 42980g ... From 1 to 6 August, 28.4 mm of precipitation fell
Calculation formula.
W from = A × F × d × (d w - d l / 10³); (1)
W from = e × F × (P w - P l / 10³); (2)
W from = F × (0.118 + (0.01995 × a × (P w - P l / 1.333)), where (3)
W from - the amount of moisture evaporating from the open water surface of the swimming pool;
A is an empirical coefficient that takes into account the presence of the number of people bathing;
F is the area of the open water surface;
d = (25 + 19 V) - moisture evaporation coefficient;
V is the air speed above the water surface;
d w, d l - respectively, the moisture content of saturated air and air at a given temperature and humidity;
P w, P l - respectively, the pressure of water vapor of saturated air in the pool at a given temperature and humidity;
e - empirical coefficient equal to 0.5 - for closed pool surfaces, 5 - for fixed open pool surfaces, 15 - small private pools with limited use time, 20 - for public pools with normal swimmers' activity, 28 - for large recreation pools and entertainment, 35 - for water parks with significant wave formation;
a - the occupancy rate of the pool by people 0.5 - for large public pools, 0.4 - for hotel pools, 0.3 - for small private pools.
It should be noted that under the same conditions, the comparative calculations carried out according to the above formulas show a significant discrepancy in the amount of evaporated moisture. However, the results obtained by calculations using the last two formulas are more accurate. In this case, the calculations according to the first formula, as practice shows, are most suitable for play pools. The second formula, in which the empirical coefficient makes it possible to take into account the highest evaporation rate in pools with active games, slides and significant wave formation, is the most universal and can be used both for water parks and for small individual swimming pools.
Daily variation of air temperature the change in air temperature during the day is called - in general, it reflects the course of the temperature of the earth's surface, but the moments of the onset of maxima and minima are somewhat delayed, the maximum occurs at 14 o'clock, the minimum after sunrise.
Daily amplitude of air temperature(the difference between the maximum and minimum air temperatures during the day) is higher on land than over the ocean; decreases when moving to high latitudes (the largest in tropical deserts - up to 40 0 С) and increases in places with bare soil. The magnitude of the daily amplitude of air temperature is one of the indicators of the continentality of the climate. In deserts, it is much higher than in areas with a maritime climate.
Annual change in air temperature(change in the average monthly temperature during the year) is determined primarily by the latitude of the place. Annual amplitude of air temperature- the difference between the maximum and minimum average monthly temperatures.
The geographical distribution of air temperature is shown using isotherm- lines connecting points with the same temperatures on the map. The distribution of air temperature is zonal; the annual isotherms in general have a sublatitudinal strike and correspond to the annual distribution of the radiation balance.
On average for the year, the warmest parallel is 10 0 N lat. with a temperature of 27 0 С is thermal equator... In summer, the thermal equator shifts to 20 0 N, in winter it approaches the equator by 5 0 N. The shift of the thermal equator in the SP is explained by the fact that in the SP the land area located at low latitudes is larger than in the SP, and it has higher temperatures during the year.
Heat on the earth's surface is distributed zonal-regional. In addition to geographical latitude, the distribution of temperatures on Earth is influenced by: the nature of the distribution of land and sea, relief, terrain height above sea level, sea and air currents.
The latitudinal distribution of annual isotherms is disturbed by warm and cold currents. In the temperate latitudes of the SP, the western shores, washed by warm currents, are warmer than the eastern shores, along which cold currents pass. Consequently, the isotherms at the western coasts bend towards the pole, at the eastern ones - towards the equator.
The average annual temperature of the SP is +15.2 0 С, and in the SP + 13.2 0 С. The minimum temperature in the SP reached –77 0 С (Oymyakon) (absolute minimum of the SP) and –68 0 С (Verkhoyansk). In SP, minimum temperatures are much lower; at the stations "Sovetskaya" and "Vostok" a temperature of –89.2 0 С (absolute minimum of SP) was noted. The minimum temperature in cloudless weather in Antarctica can drop to -93 0 C. The highest temperatures are observed in the deserts of the tropical zone, in Tripoli + 58 0 C, in California, in Death Valley, the temperature is +56.7 0 C.
How the continents and oceans affect the distribution of temperatures, give an idea of the map isonal(isonomals are lines connecting points with the same temperature anomalies). Anomalies are deviations of actual temperatures from mid-latitude temperatures. Anomalies are positive and negative. Positive anomalies are observed in summer over heated continents. Over Asia, temperatures are 4 ° C above the mid-latitude ones. In winter, positive anomalies are located above warm currents (above the warm North Atlantic Current off the coast of Scandinavia, the temperature is 28 ° C above normal). Negative anomalies are pronounced in winter over cooled continents and in summer over cold currents. For example, in Oymyakon in winter the temperature is 22 ° C below normal.
The following thermal zones are distinguished on Earth (isotherms are taken beyond the boundaries of thermal zones):
1. Hot, is limited in each hemisphere by the annual isotherm +20 0 С, passing near 30 0 s. NS. and y.sh.
2. Two moderate belts, which in each hemisphere lie between the annual isotherm +20 0 С and +10 0 С of the warmest month (July or January, respectively).
3. Two cold belts, the boundary runs along the isotherm 0 0 Since the warmest month. Areas are sometimes highlighted eternal frost located around the poles (Shubaev, 1977)
Thus:
1. The Sun is the only source of heat that is of practical importance for the course of exogenous processes in GO. Heat from the Sun enters world space in the form of radiant energy, which is then absorbed by the Earth and turns into thermal energy.
2. A sunbeam on its way is exposed to numerous influences (scattering, absorption, reflection) from various elements of the medium it penetrates and those surfaces on which it falls.
3. The distribution of solar radiation is influenced by: the distance between the earth and the sun; the angle of incidence of the sun's rays; the shape of the Earth (predetermines the decrease in the intensity of radiation from the equator to the poles). This is the main reason for the isolation of heat zones and, consequently, the reason for the existence of climatic zones.
4. The influence of the latitude of the area on the distribution of heat is corrected by a number of factors: relief; distribution of land and sea; the influence of cold and warm sea currents; circulation of the atmosphere.
5. The distribution of solar heat is further complicated by the fact that regularities and features of vertical distribution are superimposed on the patterns of horizontal (along the earth's surface) distribution of radiation and heat.
General information about air temperature
Definition 1
The indicator of the thermal state of air recorded by measuring instruments is called temperature.
The sun's rays, falling on the spherical shape of the planet, heat it up in different ways, because they come from different angles. The sun's rays do not heat the atmospheric air, while the earth's surface heats up very much and transfers thermal energy to the adjacent air layers. Warm air becomes light and rises up, where it mixes with cold air, while giving off part of its thermal energy. With height, warm air cools down and at an altitude of $ 10 $ km its temperature becomes constant $ -40 $ degrees.
Definition 2
A permutation of temperatures takes place in the stratosphere, and its indicators begin to grow. This phenomenon is called temperature inversion.
The warmest surface of the earth is where the sun's rays fall at a right angle - this is the area equator... The minimum amount of heat received polar and circumpolar regions, because the angle of incidence of the sun's rays is sharp and the rays glide over the surface, and besides, they are also scattered by the atmosphere. As a result of this, we can say that the air temperature decreases from the equator to the poles of the planet.
An important role is played by the inclination of the earth's axis to the orbital plane and the season, which leads to uneven heating of the Northern and Southern hemispheres. The air temperature is not a constant indicator, at any point in the world it changes throughout the day. On thematic climatic maps, the air temperature is shown with a special symbol, which was named isotherm.
Definition 3
Isotherms- these are lines connecting points on the earth's surface with the same temperature indicators.
On the basis of isotherms on the planet, heat belts are distinguished, going from the equator to the poles:
- Equatorial or hot zone;
- Two temperate zones;
- Two cold zones.
Thus, the air temperature is greatly influenced by:
- Geographic latitude of the place;
- Heat transfer from low latitudes to high latitudes;
- Distribution of continents and oceans;
- The location of the mountain ranges;
- Ocean currents.
Temperature change
The air temperature changes continuously throughout the day. The land heats up quickly during the day, and the air heats up from it, but with the onset of night, the land also quickly cools, and after it the air cools. Therefore, it will be cooler in the predawn hours, and warmer in the afternoon.
The exchange of heat, mass and momentum between the individual layers of the atmosphere occurs constantly. The interaction of the atmosphere with the earth's surface is characterized by the same processes and is carried out in the following ways:
- Radiation path (absorption of solar radiation by air);
- Thermal conduction path;
- Heat transfer by evaporation, condensation or crystallization of water vapor.
The air temperature, even at the same latitude, cannot be constant. On Earth, only in one climatic zone there is no daily temperature fluctuation - it is a hot or equatorial zone. Here, both nighttime and daytime air temperatures will have the same value. On the coasts of large water bodies and above their surface, the daily amplitude is also insignificant, but in the desert climate zone the difference between day and night temperatures sometimes reaches $ 50-60 $ degrees.
In temperate climatic zones, the maximum solar radiation falls on the days of the summer solstices - in the Northern Hemisphere it is July month, and in the Southern Hemisphere - January... The reason for this lies not only in the intense solar radiation, but also in the fact that the highly heated surface of the planet gives off a huge amount of thermal energy.
Middle latitudes are characterized by higher annual amplitudes. Any area of the planet is characterized by its average and absolute air temperatures. The hottest place on earth is Libyan Desert, where the absolute maximum is recorded - ($ +58 $ degrees), and the coldest place is the Russian station "East" in Antarctica - ($ -89.2 $ degrees). All average temperatures - daily average, monthly average, annual average - are arithmetic mean values of several indicators of a thermometer. We already know that air temperature decreases with height in the troposphere, but in the surface layer its distribution can be different - it can increase, decrease or remain constant. An idea of how the air temperature is distributed with height gives vertical gradient temperature (VGT). The time of the year, time of day, weather conditions affect the value of VGT. For example, the wind promotes the mixing of air and at different heights its temperature is equalized, which means that the wind decreases the VHT. The VHC drops sharply if the soil is wet, the fallow field has a VHC more than a densely sown field, because these surfaces have different temperature regimes.
The VGT sign indicates how the temperature changes with altitude; if it is less than zero, then the temperature increases with altitude. And, conversely, if the sign is greater than zero, the temperature will decrease with distance from the surface and will remain unchanged at VGT = 0. This temperature distribution with height is called inversions.
Inversions can be:
- Radiation (radiation cooling of the surface);
- Advective (formed when warm air moves to a cold surface).
There are four types of annual temperature variation based on the average long-term amplitude and time of the onset of extreme temperatures: - Equatorial type - there are two highs and two lows;
- Tropical type (maximum and minimum are observed after the solstices);
- Moderate type (maximum and minimum are observed after the solstices);
- Polar type (minimum temperature during the polar night);
The altitude of a place above sea level also affects the annual variation in air temperature. The annual amplitude decreases with height. Air temperature measurements are carried out by specialists at meteorological stations.
The daily variation of air temperature is determined by the corresponding variation of the temperature of the active surface. Air heating and cooling depends on the thermal conditions of the active surface. The heat absorbed by this surface partially spreads into the depths of the soil or reservoir, while the other part is given to the adjacent atmosphere layer and then spreads to the overlying layers. In this case, there is a slight delay in the growth and decrease in air temperature compared to the change in soil temperature.
The minimum air temperature at a height of 2 m is observed before sunrise. As the sun rises above the horizon, the air temperature rises rapidly for 2-3 hours. Then the rise in temperature slows down. Its maximum occurs in 2-3 hours after noon. Then the temperature goes down - slowly at first, and then more quickly.
Over the seas and oceans, the maximum air temperature sets in 2--3 hours earlier than over the continents, and the amplitude of the daily variation of air temperature over large bodies of water is greater than the amplitude of fluctuations in the temperature of the water surface. This is due to the fact that the absorption of solar radiation by air and its own radiation over the sea is much greater than over land, since the air contains more water vapor over the sea.
The features of the daily variation of air temperature are revealed by averaging the results of long-term observations. With such averaging, separate non-periodic disturbances in the daily temperature variation associated with the invasions of cold and warm air masses are excluded. These intrusions distort the diurnal temperature variation. For example, when a cold air mass invades during the day, the air temperature over some points sometimes decreases, but does not rise. When a warm mass invades, the temperature can rise at night.
When the weather is stable, the change in air temperature during the day is quite clearly expressed. But the amplitude of the daily variation of air temperature over land is always less than the amplitude of the daily variation of the soil surface temperature. The amplitude of the daily variation of air temperature depends on a number of factors.
The latitude of the site. With an increase in the latitude of the place, the amplitude of the daily variation of the air temperature decreases. The largest amplitudes are observed in subtropical latitudes. On average, the amplitude under consideration in tropical regions is about 12 ° C, in temperate latitudes 8-9 ° C, at the Arctic Circle 3-4 ° C, in the Arctic 1-2 ° C.
Season. In temperate latitudes, the smallest amplitudes are observed in winter, and the largest in summer. In spring they are slightly higher than in autumn. The amplitude of the diurnal temperature variation depends not only on the daytime maximum, but also on the nighttime minimum, which is the lower the longer the night is. In temperate and high latitudes, during short summer nights, the temperature does not have time to drop to very low values, and therefore the amplitude here remains relatively small. In the polar regions, under the conditions of a round-the-clock polar day, the amplitude of the daily variation of air temperature is only about 1 ° С. On a polar night, daily temperature fluctuations are almost not observed. In the Arctic, the greatest amplitudes are observed in spring and autumn. On Dikson Island, the highest amplitude during these seasons averages 5--6 ° С.
The largest amplitudes of the daily variation of air temperature are observed in tropical latitudes, and here they depend little on the season. So, in tropical deserts, these amplitudes throughout the year are 20-22 ° С.
The nature of the active surface. Above the water surface, the amplitude of the daily variation of air temperature is less than over land. Above the seas and oceans, they average 2-3 ° C. With distance from the coast to the interior of the mainland, the amplitudes increase to 20-22 ° С. Inland water bodies and highly moistened surfaces (swamps, places with abundant vegetation) have a similar, but weaker effect on the daily variation of air temperature. In dry steppes and deserts, the average annual amplitudes of the daily variation of air temperature reach 30 ° C.
Cloudy. The amplitude of the daily variation of air temperature on clear days is greater than on cloudy days, since fluctuations in air temperature are directly dependent on fluctuations in the temperature of the active layer, which in turn are directly related to the amount and nature of clouds.
Terrain relief. The daily variation of air temperature is significantly influenced by the terrain, which was first noticed by A.I. Voeikov. With concave landforms (hollows, hollows, valleys), the air comes into contact with the largest area of the underlying surface. Here the air stagnates during the day, and at night it cools over the slopes and flows down to the bottom. As a result, both daytime heating and nighttime air cooling increase within concave landforms compared to flat terrain. Thus, the amplitudes of daily temperature fluctuations in such a relief also increase. With convex landforms (mountains, hills, hills), the air comes into contact with the smallest area of the underlying surface. The influence of the active surface on the air temperature decreases. Thus, the amplitudes of the daily variation of air temperature in hollows, hollows, valleys are greater than over the plains, and over the latter they are greater than over the tops of mountains and hills.
Height above sea level. With an increase in the altitude of the place, the amplitude of the daily variation of the air temperature decreases, and the moments of the onset of maxima and minima shift to a later time. The daily variation of temperature with an amplitude of 1--2 ° С is observed even at the tropopause altitude, but here it is already due to the absorption of solar radiation by ozone contained in the air.
The annual variation of air temperature is determined, first of all, by the annual variation of the temperature of the active surface. The amplitude of the annual cycle is the difference between the average monthly temperatures of the warmest and coldest months.
In the northern hemisphere on the continents, the maximum average air temperature is observed in July, the minimum in January. On the oceans and the coast of the continents, extreme temperatures occur somewhat later: the maximum is in August, the minimum is in February - March. On land, the amplitude of the annual air temperature variation is much greater than over the water surface.
The latitude of the place has a great influence on the amplitude of the annual air temperature variation. The smallest amplitude is observed in the equatorial zone. With an increase in the latitude of the place, the amplitude increases, reaching the highest values in the polar latitudes. The amplitude of the annual fluctuations in air temperature also depends on the altitude of the place above sea level. The amplitude decreases with increasing altitude. Weather conditions have a great influence on the annual variation of air temperature: fog, rain and mainly cloudiness. The absence of cloudiness in winter leads to a decrease in the average temperature of the coldest month, and in summer - to an increase in the average temperature of the warmest month.
The annual variation of air temperature in different geographic zones is varied. According to the magnitude of the amplitude and the time of the onset of extreme temperatures, four types of the annual variation of air temperature are distinguished.
- 1. Equatorial type. In the equatorial zone, two temperature maxima are observed per year - after the spring and autumn equinox, when the sun is at its zenith above the equator at noon, and two minimums - after the winter and summer solstice, when the sun is at its lowest altitude. The amplitudes of the annual cycle are small here, which is explained by the small change in the heat inflow during the year. Over the oceans, the amplitudes are about 1 ° С, and over the continents, 5-10 ° С.
- 2. The type of temperate belt. In temperate latitudes, there is also an annual temperature variation with a maximum after the summer and minimum after the winter solstice. Over the continents of the northern hemisphere, the maximum average monthly temperature is observed in July, over the seas and coasts - in August. Annual amplitudes increase with latitude. Over the oceans and coasts, they average 10-15 ° С, over the continents 40-50 ° С, and at latitude 60 ° they reach 60 ° С.
- 3. Polar type. The polar regions are characterized by long cold winters and relatively short cool summers. The annual amplitudes over the ocean and the coasts of the polar seas are 25--40 ° С, and on land they exceed 65 ° С. The maximum temperature is observed in August, the minimum - in January.
The considered types of annual air temperature variation are revealed from long-term data and represent regular periodic fluctuations. In some years, under the influence of intrusions of warm or cold masses, deviations from these types arise. Frequent invasions of sea air masses on the mainland lead to a decrease in amplitude. The invasions of continental air masses on the coasts of seas and oceans increase the amplitude in these regions. Non-periodic temperature changes are mainly associated with the advection of air masses. For example, in temperate latitudes, significant non-periodic cooling occurs when cold air masses invade from the Arctic. At the same time, cold returns are often observed in spring. When tropical air masses invade temperate latitudes, heat returns are observed in autumn 8, s. 285 - 291.
Number: 15.02.2016
Class: 6 "B"
Lesson no.42
Lesson topic:§39. Air temperature and daily temperature variation
The purpose of the lesson:
Educational: To form knowledge about the patterns of air temperature distribution.
Developing I am : To develop skills, the ability to determine the temperature, count the daily temperature, draw up graphs, solve problems on changing temperatures, find the amplitude of temperatures.
Educational: Foster a desire to study the subject.
Lesson type: combined
Lesson type: problem learning
Equipmentlesson: ICT, thermometers, weather calendars,
I. Organizational moment: Greetings. Identification of the absent.
II. Homework check:
Test.
1. What are the reasons for the heating of the Earth?
And the polar night and the polar day
B angle of incidence of sun rays
Into the change of day and night
G pressure, temperature, wind.
2.What is the difference in surface heating at the equator and temperate latitudes:
Equatorial latitudes are warmer during the year.
B equatorial latitudes are warmed more in summer
Equatorial latitudes are heated equally throughout the year
3.How many light belts?
A 3 B 5 C 6 D 4
4. What are the features of the polar belt
A Twice a year Sun in the tropics
B During the year, there is a polar day and a polar night
In Summer, the Sun is at its zenith.
5.Does the weather change often in the tropical zone?
A Yes B No C 4 times a year
III.Preparing to explain a new topic: Write the topic of the lesson on the board, explain
IV. Explanation of new topicsNS:
Air temperature- the degree of heating of the air, determined using a thermometer.
Air temperature is one of the most important characteristics of weather and climate.
Thermometer Is a device for determining the air temperature. The thermometer is a capillary tube, soldered to a reservoir, filled with a liquid (mercury, alcohol). The tube is attached to a bar with a thermometer scale. With warming, the liquid in the tube begins to rise, with a cold snap - to fall. There are outdoor and indoor thermometers.
Daily change in air temperature - amplitude.
Studies have shown that the temperature changes over time, that is, during the day, month, year. The daily temperature change depends on the rotation of the Earth around its axis.
At night, when the sun's heat is not supplied, the Earth's surface cools. And in the afternoon, on the contrary, it heats up.
Due to this, the air temperature changes.
The lowest temperature of the day - before sunrise.
Highest temperature - 2-3 hours after noon
During the day, temperature readings at meteorological stations are taken 4 times: at 1 h, 7 h, 13 h, 19 h, then they are summed up and divided by 4 the average daily temperature
For example:
1h +5 0 C, 7h +7 0 C, 13h +15 0 C, 19h +11 0 C,
5 0 С + 7 0 С + 15 0 С + 11 0 С = 38 0 С: 4 = 9.5 0 С
V.Mastering a new topic:
Test
1. Air temperature with height:
a) decreases
b) rises
c) does not change
2. Land, unlike water, heats up:
a) slower
b) faster
3. The air temperature is measured:
a) a barometer
b) thermometer
c) hygrometer
a) at 7 o'clock
b) at 12 o'clock
c) at 14 o'clock
5. Fluctuations in temperature during the day depend on:
a) cloudiness
b) the angle of incidence of the sun's rays
6. Amplitude is:
a) the sum of all temperatures during the day
b) the difference between the highest temperature and the lowest
7. Average temperature (+2 o; +4 o; +3 o; -1 o) is equal to:
VI. Lesson summary:
1.determine the amplitude of temperatures, the average daily temperature,
Vii.Homework:
1.§39. Air temperature and daily temperature variation
Vii... Grading:
Teacher appraisal student
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