How to calculate the average temperature for a day. How to calculate the average temperature
TEMPERATURE CALCULATION PROCEDURE
USING INDIVIDUAL GRADING CHARACTERISTICS OF PLATINUM THERMOMETERS.
Annotation:
Issues considered construction of an individual calibration scale for a platinum thermometer resistance according to measurement results R0 andR100 and the estimation of the calculation accuracy was carried out. An iterative algorithm for calculating the temperature from the measured resistance of the thermometer Rt.
As you know, GOST 6651-94 (Thermal converters of resistance. General technical requirements and test methods) normalizes the error of technical resistance thermometers according to accuracy classes A, B and C, determining the maximum error for each class depending on the measured temperature. If necessary, an increase in the accuracy of temperature measurement can be achieved by means of individual calibration - measured values R 0 and R 100. However, the construction of an individual temperature scale of a thermometer requires additional calculations.
GOST 6651-94 shows the temperature dependences of the relative resistance W (t) = Rt / R 0 for two different varieties platinum ( W 100 = 1.391 and W 100 = 1.385). Note that the quantity W 100 is also associated with the quality of wire annealing in the manufacture of a sensitive element. We will assume that the dependencies given in GOST correspond exactly to temperature scale... Deviations from the given dependences for a specific sensitive platinum element are associated only with the difference in its R 0 from the nominal value (50, 100 or 500 Ohm) and the difference W 100 from 1.391. Dependencies W (t ) for different grades of platinum represent a family of similar curves, at least in the temperature range of interest to us.
Let us consider the sources of error and their influence on the measurement accuracy.
Temperature determination error
NS The temperature measurement error with platinum resistance thermometers includes the calibration error, temporary instability of the thermometer characteristics and the temperature calculation error.
Data provided by the graduation laboratory Thermiko.
1. Calibration of the thermometer
Calibration error (definition R 0, R 100) consists of:
inaccuracies resistance measurements thermometer dR = ± 1 * 10-5 (dR = ± 0.001 Ohm for R = 100 Ohm, which corresponds to D t = ± 0.0025 ° C);
reference thermometer errors D t arr = ± 0.01 ° C;
error introduced by the ice thermostat D t 0 = ± 0.0025 ° C;
error introduced by a centigrade thermostat D t 100 = ± 0.01 ° C.
Thus:
R 0 is D R 0 = ± 0.002 Ohm (relative d R 0 = ± 2 * 10-5), or in temperature equivalent ± 0.005 ° С;
maximum determination error R 100 (taking into account the reference temperature error) is D R 100 = ± 0.01 Ohm (d R 100 = ± 1 * 10-4), or in temperature equivalent ± 0.025 ° С;
maximum relative error of determination W 100 = R 100 / R 0 for thermometer:
d W 100 = (D W 100) / W 100 = (D R 100) / R 100 + (D R 0) / R 0, or
d W 100 = 1 * 10 -4 + 2 * 10 -5 = 12 * 10 -5, then absolute error D W 100 "0.0002.
2. Stability of thermometric characteristics
AND Studies of the temporal stability of characteristics carried out in "Thermiko" on platinum sensitive elements, individual platinum thermometers, sets of thermometers in the temperature range up to 200 ° C, as well as the results of secondary verification of thermometers received from our customers showed that almost all of them confirm their class, determined during calibration.
With regard to thermometers, this means that for 3 years of operation, they at least do not change their characteristics by more than 0.02¸ 0.03 ° С.
A group of platinum sensitive elements as part of verification devices was subjected to 5-fold daily thermal cycling 0 ° С - 100 ° С. R 0 per year was no more than 0.003 Ohm (~ 0.01 ° C).
As an example, we give the measurement results R 0 t 4 platinum sensitive elements in the process of operating at t = 600 ° C (table 1) and 2 thermometers at t = 200 ° C (table 2).
Table 1
|
Operating time t, hour at t = 600 ° C |
|||||
|
0 hour |
200 hours |
440 hours |
536 hours |
616 hours |
1048 hours |
table 2
|
R 0t / R 0, (R 0 nom. = 100 Ohm) Operating time t, hour at t = 200 ° C |
|||||
|
0 hour |
100 hours |
208 hours |
426 hours |
734 hours |
1159 hours |
3. Calculation of temperature
GOST 6651-94 gives the nominal static characteristics of NSX for platinum thermometers of two types: for W 100 = 1.391 and W 100 = 1.385 in accordance with the ITS-90 scale. In the temperature range of interest to us, the NSC is described by interpolation equations of the type
W t = 1 + At + Bt 2 (1), where:
For W 100 = 1.391, A 1 = 3.9692 * 10 -3 ° C -1, B 1 = -5.8290 * 10 -7 ° C -2;
For W 100 = 1.385, A 2 = 3.9083 * 10 -3 ° C -1, B 2 = -5.7750 * 10 -7 ° C -2.
To determine the A and B coefficients of the equations describing the NSC thermometers, having the value W 100 , which differs from those given in GOST, it is necessary to use the fact that the ratio of the corresponding coefficients for these two grades of platinum coincides with sufficient accuracy with the ratio of their valuesa from the equation
R t = R 0 (1+ a * t) (2):
a 2 /a 1 =0.00385/0.00391=0.98465; (1)
A 2 / A 1 = 3.9083 / 3.9692 = 0.98465 (2); - ratios 1 and 2 are equal.
((W 100) 2 / (W 100) 1) 2 = (0.995686) 2 = 0.991391 (3)
B 2 / B 1 = 5.7750 / 5.8290 = 0.990736; (4) ratios 3 and 4 coincide with an accuracy of 0.06%.
T Thus, we do without additional measurements to determine the individual static characteristic of the thermometer using the calibration characteristics at our disposal R 0 and R 100, while maintaining the GOST dependence W (t ), that is, without adding new errors associated with the approximation of experimental data.
So, for real platinum (1.392> W 100> 1.385):
A = 3.9692 * 10 -3 * ( a /0.00391) (5)
B = -5.8290 * 10 -7 * ((W 100) /1.391) 2 (6)
With an accuracy determined by the measurement error W 100 we can compose the interpolation equation (1) for platinum, which has the value a (a = (W 100-1) / 100 - thermometer sensitivity), which differs from the standard 0.00391. Note that the experimental error in the definition (see you she)
D W 100 "0.2 * 10 -3> 0.08 * 10 -3 (7)
Measurement results W 100 in our practice, as a rule, gives a normal distribution of values with a maximum at 1.3912¸ 1.3914.
4. Algorithm for calculating temperature
Calculation of temperature according to equation (1), which describes the individual NSC of the thermometer, taking into account the calibration characteristics R o and R 100 , is carried out by an iterative method according to the algorithm:
The value is determined W meas = R meas / R o. (R meas - the measured value of the resistance of the thermometer at a given temperature, R o - resistance of the thermometer at 0 o C).
Measured value W meas is compared to W races calculated by temperature t races , obtained in the previous approximation (or according to the starting value, for example, 100 about C). An amendment is determined D t = (W races - W meas) / a ( a = (W 100-1) / 100 - thermometer sensitivity), which is subtracted from t races: t meas = t races - D t ... If the condition | D t |< К расчет заканчивается (К-критерий точности расчета). При К=0.001 требуется 2-3 приближения в том случае, если стартовое значение t races significantly differs from the measured one.
If the temperature is calculated according to an individual thermometer scale, then the temperature measurement error consists of the calibration error, plusresistance measurement error,plus the error associated with the conditions of use of the thermometer.
Temperature difference determination error
Annotation:
The analysis of the error in measuring the temperature difference by difference sets of KTPTR thermometers is carried out. Comparison with the requirements of the European standard RU 1434
Temperature difference measurements D t using sets of KTPTR thermometers, except for the temperature measurement error d t , are characterized by the error in determining the temperature difference d (D t).
Differential sets of KTPTR thermometers are made by selecting pairs of thermometers according to the measurement results R 0 and R 100 ... The difference between the readings of the thermometers matched into a pair attemperatures 0 о С and 100 о С does not exceed 0.1 о С. According to the results of statistical studiesabout 2000 sets of various types of KTPTR it was found that, with a probability of 95%, the readingspairs of thermometers in the set at temperature points 0 о С and 100 о С differ by no more than 0.075 o C. The diagram shows the distribution of the relative number kits depending on thedifference in readings dT thermometers set at a temperature of 100 ° C.
Consider the diagram:
The diagram shows the dependence of the maximum inaccuracies (95% confidence level)determination of the temperature difference from the temperature of the "hot" thermometer.The boundary of the region of permissible errors is described quite well by the parabola:
d (dT) = 0.076 - 2.7 * 10 -4 * T + 3.2 * 10 -6 * T 2, о С,(8)
r de t - indications of "hot" thermometer.
Table 3 shows the values of the most probable (95% confidence level) values of the maximum error and maximum permissible error for different temperatures.
Table 3.
|
d (D t), o C (95%) |
d (D t), o C max |
|
In conclusion, I will give graphs of permissible errors d (D t) of sets according to the Technical Conditions "Thermico" and the same requirements of the European standard EN 1434. At the same time, Technical Conditions "Thermico" do not take into account the dependence of the error in determining D t on the temperature values t1 and t2 measured by thermometers kit. This relationship is not explicitly expressed in the EN 1434 standard. Perhaps it was taken into account by providing a guaranteed margin of the maximum permissible error. However, the tolerance for the maximum error of EN 1434 is five times greater than that adopted in "Thermiko".
Thermal simulation for temperature measurements
Annotation:
A method of mathematical modeling of the development in time of the process of establishing thermal equilibrium in the system of resistance thermometer - object of measurement is proposed. The temperature distribution over the thermometer design at any time is calculated, the thermal inertia index of the thermometer, the additional static temperature measurement error, depending on the way the thermometer contacts the measurement object, are determined. Recommendations for the improvement of the thermometer calibration methodology under conditions different from the operating conditions of use are proposed. The calculated data agree with the measurement results.
The main quality criterion for measuring the temperature of an object is the presence of thermal equilibrium between the thermometer and the object. However, thermal equilibrium does not at all guarantee equality temperatures thermometer and object, since there is always a heat flux passing through the thermometer from the object to the environment, which creates a certain difference between the temperature of the object and the temperature of the sensing element (SE). Any thermometer has a thermal connection with environment through its own fittings and outgoing wires. This temperature difference is an additional measurement error, the value of which is determined by the ratio of the thermal resistance between the object and the SE to the thermal resistance between the SE and the environment.
This work is devoted to assessing the additional error in temperature measurement with technical resistance thermometers associated with the conditions of heat transfer between the thermometer and the object of measurement.
When choosing the minimum immersion depth L min, providing a given level of accuracy in measuring the temperature of an object, it is necessary to take into account the nature of heat exchange between the thermometer and the measured medium. Since in most cases the working medium is a water flow, and calibration thermostats use stirred silicone oil as the working fluid, the difference physical conditions v working conditions and at verification leads to a noticeable difference in measurement results at the same immersion depth. This is especially important for thermometers in which the installation length is not much greater than the length of the sensitive element.
Usually to estimate the minimum required diving depth L min empirical relations of the type L min > n * d, where d is the diameter of the thermometer, and the number n (from 10 to 30) is selected depending on the application conditions. Obviously, such an assessment can give the most approximate results, since it does not take into account the effect on heat transfer of features of a particular thermometer design, such as the thickness of the thermometer body walls, heat transfer along the output wires, etc., which, of course, leads to an incorrect estimate L min.
In the best way a priori to assess the quality of the interaction of the thermometer with the object of measurement is the mathematical modeling of thermal processes.
Calculate the temperature distribution over a thermometer by solving differential equations heat transfer is impossible, since the design of any thermometer contains interfaces between elements with different physical properties, which excludes the continuity of functions and derivatives necessary for the solution. There remains a numerical simulation, consisting in the fact that the object of study is replaced by a system consisting of a large number sufficiently small elements within which the thermophysical properties remain homogeneous. For each element, the specific heat is determined Cp (t)... Thermal bonds between elements are calculated as thermal resistances determined by material properties and structural geometry. Further, for each element of the object, a heat balance equation is drawn up:
the amount of heat absorbed by an element over time tau should be equal algebraic sum heat fluxes passing through the element during the same time - Cp × dt = Sum (Qi) × tau , where Wed - heat capacity of the element, dt оС - heating value, tau ,with- time step, Qi , W - heat flow power along the i-th heat connection.
The starting temperature distribution in the "thermometer-object" system is selected the same as when measuring the inertia of the thermometer (t term = idem<< t объект = idem), in order to obtain an indicator of thermal inertia as an objective control parameter in the calculation process "k inertz " , the value of which can be easily measured experimentally (GOST R 50353-92). In addition, the Thermal Inertia Index "k inertz " ,
Since the thermometer has, as a rule, cylindrical symmetry, the subdivisions are defined as homogeneous annular sections with a height dx (dx = 1 mm). Heat transfer with a liquid medium is calculated at a liquid velocity of ~ 0.1 m / s (typical value for thermostats). Heat transfer outside the thermostat is calculated using the free air convection model. The temperature dependences of the thermophysical properties of working substances and materials were obtained from reference literature, with the exception of the thermal conductivity of corundum powder (grain size ~ 40 μm), to determine which special experimental studies were carried out.
The diagrams show the calculation results for the TPT-15 thermometer (used in the KTPTR-04 differential sets) with an assembly length L m = 65 mm in a thermowell (initial temperature 20 ° C) immersed in water with a temperature of 100 ° C. Ambient air temperature - 20 ° C. The lines on the graphs correspond to the temperature distribution over individual parts of the structure - outgoing wires, corundum powder filling, tube and sleeve, and a sensitive element. Calculated index of thermal inertia in waterk inertz = 10 s does not differ from the measured one by more than 1 s. After reaching thermal equilibrium mean integral the temperature of the sensing element is 99.958 ° C. That is, with this configuration, the additional measurement error is 0.042 ° C.
Table 1 shows the calculation results for the same thermometer under various conditions of use, at the temperature of the measured medium 100 oC.
Table 1
|
Measured medium |
Immersion depth LNS, mm |
k inertz , with |
Measured temperature, t оС |
additional measurement error,Δ t оС |
|
PMS100 oil |
65 |
99,870 |
0,13 |
|
|
PMS100 oil, |
85 |
99,985 |
0,015 |
|
|
Water |
65 |
99,962 |
0,038 |
|
|
Water |
75 |
99,988 |
0,012 |
|
|
Water, (in the sleeve) |
65 |
99,958 |
0,042 |
It follows from the table that for a given thermometer the immersion depth L n = L m = 65 mm is the minimum allowable when immersed in water, the error does not exceed 0.038 ° C (when installed in a sleeve - 0.042 ° C). But, when checking , when measuring the temperature of PMS100 silicone oil, which is usually used as a working liquid in calibration thermostats, the immersion depth should be increased by ~ 20 mm, (L n = L m +20 mm). This will avoid the additional error arising from the deterioration of heat transfer between the thermometer and oil, which is more viscous than water. Obviously, the minimum immersion depth should increase with increasing viscosity of the medium being measured.
It follows from the above results that verification procedure (MP) for a specific type of thermometer should, among other things, contain information about the minimum immersion depth in various working fluids, taking into account the difference in their physical properties (mainly viscosity). In this case, the minimum permissible immersion depth L min when checking in an oil thermostat, it may be more than the installation length of the thermometer L m.
The problem of heat exchange between a thermometer and a thermostat in the case of the so-called. A "dry" thermostat, in which thermal contact is made by the thermal conductivity of the air or liquid gap between the thermometer and the thermostat mounting socket, is solved in a similar way. The result is the same as the solution for a thermometer placed in a well made of the same material as the thermostat mounting socket. However, the minimum required immersion depth will increase significantly. The size of the gap between the thermometer and the sleeve also proportionally increases the additional error in temperature measurement.
Table 2 shows the results of calculating the equilibrium temperature of the sensing element and additional errorΔ t оС, as well as the indicator of thermal inertia "k inertz " . for two depths of immersion L p = 65 mm and L p = 80 mm in a copper sleeve with different sizes of the gap between the sleeve and the thermometer body. The temperature of the thermostat is 100 ° C, the ambient temperature is 20 ° C.
table 2
|
clearance b = (d g - d t )/2 , mm |
L p = 65 mm |
L p = 80 mm |
k inertz , with |
|||
|
t оС |
Δ t оС |
t оС |
Δ t оС |
L m = 65 mm |
L m = 80 mm |
|
|
0,01 |
99,96 |
0,04 |
99.987 |
0,013 |
||
|
0,05 |
99,952 |
0,048 |
99,985 |
0,015 |
||
|
99,941 |
0,059 |
99,981 |
0,019 |
10,0 |
10,0 |
|
|
0,15 |
99,930 |
0,07 |
99,976 |
0,024 |
11,7 |
11,7 |
|
99,917 |
0,083 |
99,971 |
0,029 |
13,4 |
13,4 |
|
Comparison of the results shows that at greater immersion depthsthe size of the gap has less influence on the measurement accuracy, and the value L p = 80 mm enough for technical thermometers. Thermal inertia indexk inertz hasn't changed because it hasn't changeddiameter of the thermometer section.
Lesson objectives:
- Identify the reasons for the annual fluctuations in air temperature;
- establish the relationship between the height of the Sun above the horizon and air temperature;
- the use of a computer as a technical support for the information process.
Lesson Objectives:
Educational:
- development of skills and abilities to identify the causes of changes in the annual course of air temperatures in different parts of the earth;
- building a graph in Excel.
Developing:
- the formation of skills among students to draw up and analyze graphs of the course of temperatures;
- the use of Excel in practice.
Educational:
- fostering interest in the native land, the ability to work in a team.
Lesson type: Systematization of ZUN and the use of a computer.
Teaching method: Conversation, oral questioning, practical work.
Equipment: Physical map of Russia, atlases, personal computers (PC).
During the classes
I. Organizational moment.
II. Main part.
Teacher: Guys, you know that the higher the Sun is above the horizon, the greater the angle of inclination of the rays, so the surface of the Earth heats up more, and from it the air of the atmosphere. Let's take a look at the picture, analyze it and draw a conclusion.
Student work:
Work in a notebook.
Record in the form of a diagram. Slide 3
Writing in text.
Heating of the earth's surface and air temperature.
- The earth's surface is heated by the Sun, and the air heats up from it.
- The earth's surface heats up in different ways:
- depending on the different heights of the Sun above the horizon;
- depending on the underlying surface.
- The air above the earth's surface has different temperatures.
Teacher: Guys, we often say that it is hot in summer, especially in July, and cold in January. But in meteorology, in order to establish which month was cold and which was warmer, they calculate by the average monthly temperatures. To do this, add up all the average daily temperatures and divide by the day of the month.
For example, the sum of the average daily temperatures in January was -200 ° С.
200: 30 days ≈ -6.6 ° C.
Observing the air temperature throughout the year, meteorologists found that the highest air temperature is observed in July, and the lowest in January. And we also found out that the highest position of the Sun is -61 ° 50 'in June, and the lowest - in December 14 ° 50'. During these months, the longest and smallest length of the day is observed - 17 hours 37 minutes and 6 hours 57 minutes. So who's right?
Students' answers: The thing is that in July the already heated surface continues to receive, although less than in June, but still a sufficient amount of heat. Therefore, the air continues to heat up. And in January, although the arrival of solar heat is already increasing somewhat, the Earth's surface is still very cold and the air continues to cool from it.
Determination of the annual amplitude of air.
If we find the difference between the average temperature of the warmest and coldest months of the year, then we will determine the annual amplitude of fluctuations in air temperature.
For example, the average temperature in July is + 32 ° С, and in January -17 ° С.
32 + (-17) = 49 ° C. This will be the annual amplitude.
Determination of the average annual air temperature.
In order to find the average temperature of the year, add up all the average monthly temperatures and divide by 12 months.
For example:
Student work: 23:12 ≈ + 2 ° С - average annual air temperature.
Teacher: You can also determine the multi-year t ° of the same month.
Determination of long-term air temperature.
For example: average monthly temperature in July:
- 1996 - 22 ° C
- 1997 - 23 ° C
- 1998 - 25 ° C
Children's work: 22 + 23 + 25 = 70: 3 ≈ 24 ° C
Teacher: Now guys find the city of Sochi and the city of Krasnoyarsk on the physical map of Russia. Determine their geographic coordinates.
Students use atlases to determine the coordinates of cities, one of the students on the map at the blackboard shows cities.
Practical work.
Today, in the practical work that you perform on a computer, you have to answer the question: Will the graphs of the air temperatures for different cities coincide?
Each of you has a piece of paper on the table, which presents an algorithm for performing the work. The PC contains a file with a ready-to-fill table containing free cells for entering the formulas used to calculate the amplitude and average temperature.
Algorithm for performing practical work:
- Open the My Documents folder, find the file Practice. work 6 cl.
- Enter the air temperature values in Sochi and Krasnoyarsk in the table.
- Use the Chart Wizard to build a graph for the values of the A4: M6 range (name the graph and axes yourself).
- Zoom in on the plotted graph.
- Compare (verbally) the results obtained.
- Save the work under the name PR1 geo (surname).
| month | Jan. | Feb | March | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| Sochi | 1 | 5 | 8 | 11 | 16 | 22 | 26 | 24 | 18 | 11 | 8 | 2 |
| Krasnoyarsk | -36 | -30 | -20 | -10 | +7 | 10 | 16 | 14 | +5 | -10 | -24 | -32 |
III. The final part of the lesson.
- Do you have the same temperature graphs for Sochi and Krasnoyarsk? Why?
- Which city has lower air temperatures? Why?
Output: The greater the angle of incidence of the sun's rays and the closer the city is to the equator, the higher the air temperature (Sochi). The city of Krasnoyarsk is located further from the equator. Therefore, the angle of incidence of the sun's rays is smaller here and the air temperature reading will be lower.
Homework: p. 37. Build a graph of the course of air temperatures based on your observations of the weather for the month of January.
Literature:
- Geography 6kl. T.P. Gerasimova N.P. Neklyukova. 2004.
- Geography lessons 6th grade. OV Rylova. 2002.
- Lesson development 6kl. ON. Nikitin. 2004.
- Lesson development 6kl. T.P. Gerasimova N.P. Neklyukova. 2004.
The average daily or average monthly air temperature is important for the characteristics of the climate. As with any average, it can be calculated by making a few observations. The number of measurements, as well as the accuracy of the thermometer, depend on the purpose of the study.
You will need
Thermometer;
- paper;
- pencil:
- calculator.
Sponsored by the placement of P & G Articles on "How to calculate the average temperature" How to find the average kinetic energy of molecules How to determine the average temperature How to find the air temperature at constant pressure
Instructions
Use a regular outdoor thermometer to find the average daily outside temperature. To characterize the climate, its accuracy is quite sufficient, it is 1 °. In Russia, the Celsius scale is used for such measurements, but in some other countries the temperature can also be measured in Fahrenheit. In any case, it is necessary to use the same device for measurements, in extreme cases - another, but with exactly the same scale. It is highly desirable that the thermometer be calibrated against the reference. Take readings at regular intervals. This can be done, for example, at 0 o'clock, at 6, 12 and 18. Other intervals are also possible - after 4, 3, 2 hours, or even hourly. Measurements must be carried out under the same conditions. Hang the thermometer so that it is in the shade even on the hottest day. Count and write down how many times you looked at the thermometer. At weather stations, observations are usually carried out after 3 hours, that is, 8 times a day. Add up all readings. Divide the total by the number of observations. This will be the average daily temperature. A situation may arise when some readings will be positive, while others will be negative. Sum them up the same way you would any other negative numbers. When adding two negative numbers, find the sum of the modules and put a minus in front of it. For positive and negative numbers, subtract the lower number from the larger number and place the higher number in front of the result. To find the average daytime or nighttime temperature, determine when noon and midnight are on the astronomical clock in your area. Daylight saving and daylight saving time shifted these moments, and noon in Russia comes at 14 o'clock, not at 12. For the average night temperature, calculate the moments six hours before midnight and the same time after it, that is, it will be 20 and 8 hours. Two more moments when you need to look at the thermometer - 23 and 5 o'clock. Take readings, add up the results, and divide by the number of measurements. Determine the average daytime temperature in the same way. Calculate the average monthly temperature. Add up the daily average for the month and divide by the number of days. In the same way, you can calculate the monthly average values for day and night temperatures. If observations are carried out systematically over several years, it is possible to calculate the climatic norm for each specific day. Add up the average daily temperatures for a specific day of a given month over several years. Divide the sum by the number of years. In the future, it will be possible to compare the average daily temperature with this value. How simple
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1. What is the average daily temperature?
The value of the average daily temperature is calculated as the arithmetic average over 8 periods of meteorological days.
2. On your website, in the Climate Monitor, there is some nonsense in the values of the minimum and maximum temperatures. I compare with other sites and see significant discrepancies: the lows are often underestimated and the highs are overestimated. What's the matter?
Unfortunately, meteorological stations in Russia and the CIS transmit to international exchange only the daytime maximum and the nighttime minimum, you can see these values on other sites. However, often (most often in winter) there is a monotonous increase (decrease) in temperature during the day, therefore, the highest air temperature is often not during the day, but at the beginning of the meteorological day, roughly speaking, the night before. Also, as a result of the invasion of cold air during the day or strong cooling of the air on a long winter evening, the air temperature at the end of the meteorological day may be lower than in the morning hours. Therefore, we decided to consider the daily minimum the lowest temperature value selected from 8 urgent values and the night minimum, and the daily maximum - the highest temperature value selected from the 8 urgent values, the value recorded at the beginning of meteorological days and the daytime maximum.
3. What is a meteorological day and when does it start?
It depends on what time zone the weather station is in. WMO (World Meteorological Organization) has set the start time of the meteorological day for different time zones:
0 hours: 19-24 time zones;
6 hours: 13-18 time zones;
12 hours: 7-12 time zones;
18 hours: 1-6 time zones.
(Universal time, UT). Thus, on the ETR the meteorological day begins at 18 UT. At this time, the results of the day are summed up: the average and extreme values of air temperature and other meteorological parameters are calculated, the amount of precipitation is determined, etc.
4. What is the difference between Moscow and Universal Time?
+4 hours in summer and winter.
5. I went to the Weather Records (Climate Monitor) section. I look and think: was it too cold (hot) yesterday in the city N: -96 ° (+ 75 °)? Antarctica (Africa) is resting!
Air temperature and precipitation monitoring services are fully automated. Observers at meteorological stations encode weather information with a special code KN-01, from where it, having traveled a long way, goes to the world data center in Washington, and from there - to our website, where it is decoded and processed. Sometimes during the coding process, errors occur that go through this entire chain unchanged. Currently, the site has an automated control of air temperature values, so most of the errors are corrected within 12 hours. Unfortunately, the algorithm cannot correct some errors. Such errors have to be corrected manually. Therefore, we will be grateful to you if you inform us about the noticed inaccuracies.
6. Are you planning to expand the list of stations in the Climate Monitor?
This is not planned because in monitoring, the focus is not on quantity, but on quality. Errors are inevitable in climate norms and current data. And the number of stations for which we can carry out a manual check is limited for obvious reasons.
7. For what period have you calculated climatic data for cities in the Climate of the world section?
Average values of air temperature and precipitation, average values of wind, upper and lower clouds, air humidity, snow cover, the number of days with different types of precipitation, clear, cloudy and cloudy days are calculated based on data for 1981-2010. The number of days with different phenomena and the frequency of occurrence of different types of clouds are also calculated based on data for 1981-2010. When determining the extreme values of meteorological elements, data were taken for the entire observation period: archives from the sites meteo.ru, ncdc.noaa.gov, as well as other sources were used.
8. What sources do you get the weather forecast from?
Our website contains an extended 5-day combined weather forecast based on data from several global atmospheric models. Updating the forecast is fully automated and takes place without the participation of forecasters and the control of the site administrator. In addition, the comfort of the weather is calculated using a unique method.
9. Believing the weather forecast on your website, I didn't take an umbrella (hat) with me and got wet like a dog (frostbitten ears), etc.
I found some errors in your data tables. Why are you giving false information?
We are not responsible for the accuracy of forecasts and the reliability of other meteorological data, because all information presented on the site is unofficial.
10. What should I do if I have not found an answer to my question here?
Write to us by email, we will try to answer your question.
The rays of the sun, when passing through transparent substances, heat them very weakly. This is due to the fact that direct sunlight practically does not heat the atmospheric air, but strongly heats the earth's surface, which is capable of transferring thermal energy to the adjacent air layers. As it warms up, the air becomes lighter and rises higher. In the upper layers, warm air mixes with cold air, giving it part of the thermal energy.
The higher the heated air rises, the more it cools.
The air temperature at an altitude of 10 km is constant and is -40-45 ° C.
A characteristic feature of the Earth's atmosphere is a decrease in air temperature with altitude. The temperature sometimes rises as the altitude rises. The name of this phenomenon is temperature inversion (temperature permutation).
Temperature change
The appearance of inversions can be caused by the cooling of the earth's surface and the adjacent air layer in a short period of time. This is also possible when dense cold air moves from mountain slopes to valleys. During the day, the air temperature is constantly changing. During the daytime, the earth's surface heats up and heats up the lower air layer. At night, along with the cooling of the earth, the air is cooled. It is cooler at dawn and warmer in the afternoon.
There is no daily temperature fluctuation in the equatorial zone. Nighttime and daytime temperatures are the same. The daily amplitudes on the coasts of seas, oceans and above their surface are insignificant. But in the desert zone, the difference between night and day temperatures can reach 50-60 ° C.
In the temperate zone, the maximum amount of solar radiation on Earth falls on the days of the summer solstices. But the hottest months are July in the Northern Hemisphere and January in the Southern. This is due to the fact that despite the fact that solar radiation is less intense during these months, a huge amount of thermal energy is given off by the highly heated earth's surface.
The annual temperature range is determined by the latitude of a particular area. For example, at the equator it is constant at 22-23 ° C. The highest annual amplitudes are observed in the mid-latitude regions and in the interior of the continents.
Any terrain is also characterized by absolute and average temperatures. Absolute temperatures are determined through long-term observations at meteorological stations. The hottest region on Earth is the Libyan Desert (+58 ° C), and the coldest one is Vostok Station in Antarctica (-89.2 ° C).
Average temperatures are established when calculating the arithmetic mean values of several thermometer indicators. This is how the average daily, average monthly and average annual temperatures are determined.
In order to find out how heat is distributed on the Earth, temperature values are plotted on a map and dots with the same values are connected. The resulting lines are called isotherms. This method allows you to identify certain patterns in the distribution of temperatures. Thus, the highest temperatures are recorded not at the equator, but in tropical and subtropical deserts. A decrease in temperatures from the tropics to the poles in two hemispheres is characteristic. Taking into account the fact that in the Southern Hemisphere water bodies occupy a larger area than land, the temperature amplitudes between the hottest and coldest months are less pronounced there than in the Northern.
According to the location of isotherms, seven thermal zones are distinguished: 1 hot, 2 moderate, 2 cold, 2 permafrost zones.
Related materials:
1. Atmosphere
3. Climatic zones
News and Society
Annual temperature range: how to calculate, calculation features
We all know that the inhabitants of the globe live in completely different climatic zones. That is why with the onset of cold weather in one hemisphere, warming begins in the other. Many go on vacation to bask in the sun in other countries and do not even think about the annual temperature range. How to calculate this indicator, children will learn from school. But with age, it is often simply forgotten about its importance.
Definition
Before calculating the annual temperature amplitude from the graph, it is necessary to remember what this definition is. So, the amplitude, in itself, is defined as the difference between the maximum and minimum indicator. 
In the case of calculating the annual temperature, the amplitude will be the thermometer readings. For accurate results, it is important that only one thermometer is used at all times. This will allow you to independently determine the graph of the course of temperatures in a specific region. How to calculate the annual amplitude in climatology? Experts use for this the average readings of monthly temperatures over the past years, so their indicators always differ from those calculated independently for their locality.
Factors of change
So, before calculating the annual amplitude of air temperature, you should take into account several important factors that affect its performance.
First of all, this is the geographical latitude of the required point. The closer the region is to the equator, the less will be the annual fluctuation in thermometer readings. Closer to the poles of the globe, the continents feel the seasonal climate change more strongly, and, consequently, the annual temperature range (how to calculate - later in the article) will proportionally increase. 
Also, the proximity of the region to large bodies of water also affects the air heating indicators. The closer the coast to the sea, ocean or even a lake, the milder the climate, and the change in temperature is less pronounced. On land, the temperature difference is very high, both annual and daily. Of course, this situation can be changed by air masses often coming from the sea, as, for example, in Western Europe.
The temperature range also depends on the region's altitude above sea level. The higher the desired point is, the less the difference will be. It shrinks by about 2 degrees with every kilometer.
Before calculating the annual temperature amplitude, seasonal climatic changes must also be taken into account. Such as monsoons or droughts.
Daily Amplitude Calculations
Each owner of a thermometer and free time can independently carry out such calculations. To get the best accuracy for a particular day, take a thermometer reading every 3 hours, starting at midnight. Thus, from the obtained 8 measurements, it is necessary to select the maximum and minimum indicators. After that, the smaller is subtracted from the larger, and the result obtained is the daily amplitude of a particular day. This is how specialists perform calculations at meteorological stations. 
It is important to remember the elementary rule of mathematics that a minus for a minus gives a plus. That is, if the calculations are carried out in the cold season, and the daily temperature ranges from positive during the day to negative at night, then the calculation will look something like this:
5 - (-3) = 5 + 3 = 8 - daily amplitude.
Annual temperature range. How to calculate?
Calculations to determine annual fluctuations in thermometer readings are carried out in a similar way, only the maximum and minimum values are taken by the average thermometer readings of the hottest and coldest months of the year. They, in turn, are calculated by obtaining average daily temperatures.
Obtaining an average reading
To determine the average readings for each day, it is necessary to add up all the readings recorded over a given period of time into a single number, and divide the result by the number of added values. The maximum accuracy is obtained by calculating the average from a larger number of measurements, but more often than not, taking data from the thermometer every 3 hours is sufficient. 
In a similar way, data on average temperatures for each month of the year are calculated from the already calculated daily averages.
Calculation
Before determining the annual amplitude of air temperature in a particular region, you should find the maximum and minimum average monthly temperature. From the larger it is necessary to subtract the smaller, also taking into account the rules of mathematics, and the result obtained is considered the same desired annual amplitude.
Importance of indicators
In addition to calculating air temperatures for various geographic purposes, temperature differences are important in other sciences as well. So, paleontologists study the vital activity of extinct species, calculating the amplitudes of temperature fluctuations in entire epochs. To do this, they are helped by various soil samples and other thermography methods.
Investigating the operation of internal combustion engines, experts define periods as certain intervals of time, constituting a fraction of a second. For the accuracy of measurements in such situations, special electronic recorders are used. 
In geography, temperature changes can also be recorded in fractions, but this requires a thermograph. Such a device is a mechanical device that continuously records temperature data on tape or digital media. It also determines the amplitude of changes, taking into account the set time intervals. Such precise instruments are used in areas where human access is closed, for example, in the zones of nuclear reactors, where every fraction of a degree is important, and it is necessary to constantly monitor their changes.
Conclusion
From the foregoing, it is clear how the annual temperature amplitude can be determined, and what this data is for. To facilitate the task, experts divide the atmosphere of the entire planet into specific climatic zones. This is also due to the fact that the range of temperatures across the planet is so wide that it is impossible to determine the average indicator for it, which would correspond to reality. The division of the climate into equatorial, tropical, subtropical, temperate continental and maritime, allows you to create a more realistic picture, taking into account all the factors affecting the temperature indicators in the regions. 
Thanks to this distribution of zones, it can be determined that the temperature amplitude increases depending on the distance from the equator, the proximity of large bodies of water and many other conditions, including the period of the summer and winter solstices. Interestingly, depending on the type of climate, the duration of the transitional seasons, as well as the peaks of hot and cold temperatures, vary.
Source: fb.ru
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Weather in Moscow. Air temperature and precipitation. June 2018
The table shows the main characteristics weather in Moscow- air temperature and amount of precipitation given for every day in June 2018.
Average monthly temperature in June: 17.0 °... Actual temperature of the month according to observations: 13.7 °... Deviation from the norm: -2.4 °.
The norm of the amount of precipitation in June: 80 mm... Precipitation fell: 33 mm... This amount is 41%
from the norm.
The lowest air temperature (5.6 °
) was on June 1. The highest air temperature (26.1 °
) was on June 3.
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Air temperature in Moscow.
June 2018
Explanations for calculating average daily values... The air temperature and precipitation values in the table are given for the meteorological day, which in Moscow begins at 18:00 UTC (at 21:00 local time). Be careful: if the daily temperature is incorrect, the maximum per day can be noted at night, and the minimum - during the day. Therefore, the discrepancy between the values indicated in the table and the night lows and daily highs from the archive is not an error!
Explanations for the graph. The current minimum, average, maximum air temperatures in Moscow are shown on the graph by solid lines in blue, green and red, respectively.
Normal values are shown with solid thin lines. The absolute maximums and minimums of temperature for each day are indicated by bold points, respectively, in red and blue.
Explanations for daily and monthly records. Temperature records for each day are defined as the lowest and highest values across a series of daily resolution data. To monitor the weather in Moscow, daily data were taken for the period 1879-2018 biennium Monthly weather records are derived from a series of monthly resolution data. Monthly data are taken for the period 1779-2018 biennium - air temperature, 1891-2018 biennium - precipitation.
Select the month you are interested in (starting in January 2001) and press the "Enter!"
How to calculate the average temperature
The average daily or average monthly air temperature is important for the characteristics of the climate. As with any average, it can be calculated by making a few observations. The number of measurements, as well as the accuracy of the thermometer, depend on the purpose of the study. You will need
Instructions
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© CompleteRepair.Ru
Average daily temperature
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The warm period of the year is characterized by an average daily outside air temperature of 10 C and above, and the cold and transitional one is lower - NO C.
The warm period of the year is characterized by an average daily outside temperature of 10 C and above, and the cold and transitional one is below 10 C.
Pupation in spring begins after the average daily temperature is above 10 C and usually occurs during the period of staining of apple buds. Females need additional nutrition, or at least drip moisture.
When the temperature of the oil product in the tank is higher than the average daily air temperature and the turnover rate of 200 and higher per year, the effectiveness of the use of reflective coatings is insignificant.
The duration of development of one generation at an average daily temperature of 21 - 23rd relative air humidity of 63 - 73% is 25 - 30 days. With an increase in temperature, the duration of development decreases.
Most flowers grow well at an average daily temperature of 12 to 18 - 20 C.
For rough calculations, the difference between the maximum and average daily outside air temperature L / n is 9 C for areas with a dry climate and 7 C for areas with a temperate humid climate.
For rough calculations, the difference between the maximum and average daily outdoor air temperature Ata is 9 C for areas with a dry climate and TS for areas with a temperate humid climate.
For the design temperature of the outside air, the average daily temperature (average over the last 5 years according to meteorological observations) is taken with a repeatability of at least three times a month, which, when coinciding with the unfavorable wind direction, gives the worst conditions for rolling off cars.
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Strong winds can significantly increase the rate of heat loss in cold weather. Wind chilling can have a certain effect on human skin. All you need to calculate the wind chill factor is to measure the air temperature and wind speed. Both numbers can be viewed from the weather forecasts. However, you can measure wind speed at home with just small paper cups and plastic straws.
Steps
Calculating the wind chill factor
- If you measured in ºF and miles: wind chill temperature = 35.74 + 0.6215 T - 35.75V 0.16 + 0.4275TV 0.16
- If you measured ºC and km / h: wind chill temperature will be = 13.12 + 0.6215 T - 11.37V 0.16 + 0.3965TV 0.16
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Adjust according to the sun. The bright sun helps the temperature rise to +10 - + 18ºF (+5.6 - + 10ºC). There is no official formula to measure this effect, but you need to be aware that exposure to the sun will cause the weather to appear warmer than measured by the wind chill formula.
The wind chill coefficient measures the loss of body heat in an exposed area of skin at low temperatures. In extreme conditions, this can be an important factor in determining how soon frostbite occurs. If the wind chill temperature is -19ºF (-28ºC), frostbite on exposed skin will occur in 15 minutes or less. If the temperature is -58ºF (-50ºC), frostbite on exposed skin will occur within 30 seconds.
Using the wind chill calculator
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Find an online wind chill ratio calculator. Try the following sites: the US National Weather Service, freemathhelp.com, or onlineconversion.com.
- All of these calculators use the new wind chill formula adopted in the United States and other countries in 2001. If you are using a different calculator, try to find one that uses this formula. Calculations derived from old formulas may turn out to be erroneous.
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Find readings for air temperature and wind speed. These indicators can be found from weather forecasts available on websites, on TV and radio, or in newspapers.
Multiply your wind speed by 0.75. Since, according to the weather forecast, the wind speed is determined at ground level, the wind speed must be multiplied by 0.75 to get a more accurate wind speed that corresponds to the level of a human face.
Enter the metrics into the calculator. Make sure you select the correct units of measure (for example, miles per hour or ºC). Click "OK" or another similar button to see the wind chill ratio.
Measuring wind speed
- If there is nothing sharp at hand, then the holes can be made with a pencil.
Decide if you should buy or make your own anemometer. An anemometer is an instrument for measuring wind speed. You can buy it online, or make a simple anemometer yourself within 30 minutes using the steps below. If you have already purchased an anemometer, then skip this step and go to the one in which you will learn how to make calculations.
Punch holes in small paper cups. Take four small paper cups and punch a single hole in each of them 1.25 cm below the rim. Take the fifth glass and poke four evenly spaced holes, about 6 mm below the rim, and make the fifth hole in the center of the bottom.
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Insert a 2.5 cm plastic straw into the single hole cup. Pass the other end of the straw through the two holes in the five-hole cup. Insert the free end of the straw into another single-hole cup. Rotate the single-hole cups strung on the same straw so that they point in opposite directions. Use a stapler to attach the straws to the glasses.
Repeat with two other cups and a second straw. Place the cups one after the other so that the bottom of the next one looks into the open part of the previous one. Staple the straws to the cups.
Make a base for the anemometer. Adjust both straws so that all four cups are the same distance from the center. Stick a small pin through the intersection of the two straws. Insert a pencil with an eraser end through the hole in the base of the center cup, and gently stick the mace into it. You can now hold the anemometer by the tip of a pencil and use it to measure wind speed.
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Count the number of revolutions that the anemometer makes. Keep the anemometer upright in a windy area. Keep an eye on one cup (mark it with a marker for ease) and count the number of revolutions it takes. Using a stopwatch, time the time for 15 seconds, and stop the countdown. Multiply that number by four to get the number of revolutions per minute (RPM).
- For more accuracy, count the number of revolutions of the cup in 60 seconds (then, you do not need to multiply by 4).
Measure the temperature T. Use a thermometer or check the temperature in your area on the weather forecast website. You can measure the temperature in Fahrenheit or Celsius. To measure wind speed, read the next step carefully to find out which device to use.
Find or measure wind speed V. You can find wind speed estimates on most weather forecast sites or online by searching for "wind speed + (your city name)". If you have an anemometer (you can make one yourself using the instructions below), then you can measure the wind speed yourself. If you are measuring temperature in ºF, then use wind speed in miles per hour (miles per hour). If you are measuring in ºC, then use the wind speed measurement in kilometers per hour (km / h). If necessary, use the [http://www.metric-conversions.org/speed/knots-to-kilometers-per-hour.htm website to convert knots to km / h.
Enter these values into the formula. Over the years, the wind chill coefficient has been calculated using different formulas in different regions. But today we will be calculating with the formula used in the UK, USA and Canada, which was developed by an international team of researchers. Enter the numbers you received into the formula below. Replace T with air temperature and V with wind speed:
