The meteorological archive "TM1-SROKI" contains the results of four main urgent meteorological observations at stations in the USSR for the period 1936-1965. Since 1985, this archive has been included in the State Data Fund on the State of the Natural Environment (Obninsk, VNIIGMI-MCD), and is also part of the information base of the Meteorology and Climate database. This document contains a description of the "TM1-SROKI" archive, developed as part of the second stage of the "Meteorology and Climate" database. The development of this description of the "TM1-SROKI" archive was based on a similar description submitted to the State Data Fund on the State of the Natural Environment when applying for the creation of this archive in 1984 [1]. Due to the fact that this description is not complete enough and requires the use of hard-to-find additional literature, an attempt was made to develop a closed description containing all the information necessary for the user of this archive. The result of this effort—this document—is significantly larger than the previous description. This may, to some extent, complicate its use, but the document's self-contained nature, which allows most users to avoid the need for additional literature, should somewhat compensate for the increased volume. On the other hand, it is planned to incorporate the information from this document into an "e-book" that will contain an organized description of the entire "Meteorology and Climate" database. In this case, the comprehensiveness of the information in the "e-book" will already be an advantage.

It is natural to expect that this document is not without its shortcomings. Therefore, any comments and recommendations for its improvement will be gratefully received. Please send written messages to: 249020, Obninsk, Koroleva Street, 6, VNIIGMI-MCD, Climatology Department.

1. General Description of the Archive

1.1. Origin of the Archive

The "TM1-SROKI" archive was created by transferring data from TM-1 tables to the magnetic types (MT) Unified System of Electronic Computers. Initially, punched card indexes containing daily-resolution data from TM-1 tables for 1936-1965 were created with the intention of processing them using punched-card machines (SPM). With this in mind, the TM-1 tables were presented in a format convenient for subsequent transfer to punched cards (TMM-1 tables). Specifically, the data in the TMM-1 tables is recorded in the order in which it should be entered onto a punched card, and the table header indicates the punched card positions for each data element. Several versions of instructions similar to [2, 3, 4] were used during the preparation of the TMM-1 tables and subsequent data entry stages. The procedure for recording data in the TMM-1 tables was regulated by the "Instructions for Hydrometeorological Stations and Posts," Issues 3, Parts 1 and 2 [5, 6].

1.2. Archive Status

1.2.1. Archive Composition

The archive consists of individual data sets (files). One file contains data from the main meteorological observations at stations across the USSR for the period January 1, 1936, through December 31, 1965.

List of meteorological elements contained in the archive:

• air temperature;
• air humidity characteristics (relative and absolute humidity, saturation deficit, and dew point temperature);
• wind characteristics (wind direction, speed, and regularity);
• cloud characteristics (base height; total and lower cloud cover; cloud shapes);
• weather characteristics (during and between periods);
• precipitation amount;
• horizontal visibility;
• soil surface characteristics (surface condition and temperature).

1.2.2. Archive Quality Assessment

This meteorological archive contains data obtained through numerous operations by thousands of people. These include meteorological network observers, data punching personnel, data processing bureau workers operating punch machines, programmers, computer operators, etc. Data errors may occur at all stages of processing, so the archive structure includes a number of tools to alert the user to any defects already discovered.

First, the user is interested in the completeness of the data series. It is necessary to distinguish between systematic data gaps (missing data due to station outages or data loss due to punch card degradation) and random gaps. Regarding systematic gaps, this archive can generally be used for mass processing, although no comprehensive data control has been performed. A program for logical control of archive data "TM1-DAY" and "TM1-TERMS" [11] has been developed, but it has not yet been used systematically.

At the same time, there is a group of stations for which the data is quite complete. These are primarily meteorological stations included in the International Meteorological Monthly (IMM) (so-called IMM stations).

Further, to assess the feasibility of using meteorological values, each archive element is accompanied by an additional attribute, called a "quality attribute," which takes the following values:

0 - value is reliable
2 - value is questionable
3 - value is rejected
4 - observations were not conducted

For quality attribute values ​​of 3 or 4, the element field is filled with the character 9. In all positions of the field, key elements of the element records do not have a quality attribute.

Absence of data for a given day is indicated by setting the "day" field to "99" (see Section 1.6.2. "Data File Structure").

1.2.3. User Recommendations for Processing Individual Meteorological Elements

Instruments at stations used to measure wind speed (light and heavy weathervanes, anemorumbometers) have varying accuracy over different speed ranges. In the practice of processing wind speed data in urgent resolution, it is common to convert the data to a conventional instrument, such as an anemorumbometer. This requires using the historical data of a specific station. The "Station History" database is maintained by the Climatology Department of the All-Russian Scientific Research Institute of Hydrometeorological Information (VNIIGMI-MDC), but the necessary information can be obtained from the Hydrometeorology Department (UGM), which includes the station in question. In this case, possible station relocations can also be taken into account.

The section "Description of Meteorological Elements" provides a brief description of each element, its definition method, units of measurement, change ranges, rules for recording the element, rules for encoding it, and the position of the field in the record.

1.2.4. List of software tools in the State Hydrometeorological Committee's OFAP that allow for archival data processing

a) Logical control program for archives of basic meteorological observations for the period 1936-1965 (CNTR4).[10]

b) SUD-AISORI environment programs [11-20]

1.3. Archive Development Prospects

It is planned to create an archive covering the full list of stations in the former USSR (approximately 2,000).

1.4. Spatial Distribution of Observation Points

Observation points (stations) are distributed unevenly across the former Soviet Union. A denser network of stations is found in the European part of the former USSR.

1.5. Observation Periods

Information about the observation period and any breaks within it is provided in the YOD description of a given station, in the "Abstract" section.

Observations were conducted during climatological periods associated with a specific position of the sun relative to the meridian plane of the observation point. The observation periods changed repeatedly throughout the operation of the meteorological station network. In describing the observation periods, we fully cite the section "Observation Periods" from [7] concerning the period 1936-1965.

In 1935-36, four equally spaced observation times were introduced: 1 p.m., 7 a.m., 1 p.m., and 7 p.m. (with the previously introduced continuous time counting from 0-24 hours from 12 a.m.), which were intended to provide better coverage of the diurnal cycle of meteorological elements.

After the introduction of four observation times, all phenomena observed after 7 p.m. and during the night are recorded in the line for the following day, in chronological order. Phenomena observed at night may be accompanied by a short time mark "n" instead of the exact time.

When calculating the number of days with phenomena, the day is counted from 7 p.m. to 7 p.m. In accordance with the above.

For stations where it was not possible for one reason or another to introduce nighttime observations after January 1, 1936, the 9:00 p.m. period was temporarily retained for coordination purposes. Complete series of observations were made at 7:00 a.m., 1:00 p.m., and 7:00 p.m. At 9:00 p.m., observations were made according to a reduced program - on cloudiness, wind, temperature, and humidity; according to the 1940 guidelines, observations of visibility and pressure were also made.

Precipitation observations were initially made at stations at 8:00 a.m. and at 8:00 a.m.; in 1870 - at 7:00 a.m. in summer and at 8:00 a.m. in winter; subsequently - at 7:00 a.m. all year round; after the introduction of four observation periods - at 7:00 a.m. and at 7:00 PM.

Snow cover observations are made at or near the morning observation time, when there is sufficient light.

Since 1941, observations at Class 3 stations (at outposts) have been made at 8:00 AM and 8:00 PM local civil time. A day is counted from 8:00 PM to 8:00 PM.

For stations serving aviation, additional observation times are introduced by special order.

1.6. Data File Structure

The archive is recorded on standard 0.5-inch magnetic tapes in a format oriented towards processing in the ES computer environment in the DKOI code (IBM 360, 370 and compatible computer models in the EBCDIC code). The organization of the data in the archive is subject to the requirements of the State Data Fund on the State of the Natural Environment. This is, first of all, the file structure, the organization of data on the MT volume. The file structure provides a formal description in the hydrometeorological data description language (YOD-description) [12], adopted as mandatory in the Goskomhydromet system. This description is available on each MT archival volume (usually, the last file on the volume) and can be provided to the user. The data recording density on the MT is 800 BPI, but during copying it can be changed to 1600 BPI or 6250 BPI. The name of the data file and YOD-description coincides with the name of the station (in Russian). The file containing the YOD description of this archive is written before the data file. A sample YOD description of the archive is attached.

The data file contains records 3581 bytes long. Records in the archive are not locked. When copying data, records can be locked at the user's discretion. File records are sorted in ascending order by key record elements: year, month, and term.

"Year" takes values ​​936,..., 965. The "year" field occupies positions 10-12 in the record.

"Month" takes a value from 1 to 12, with a leading zero usually present. For example, January might be encoded as 01 or b1, where b is the space code. The "Month" field occupies positions 13-14 in the record.

"Date" takes the values ​​01, 07, 13, 19. The "Date" field occupies positions 15-16 in the record.

In each record, positions 1-9 contain a station code, called a "coordinate number." The structure of the coordinate number is as follows:

Positions 1-4 define the latitude of the station location with an accuracy of 0.1 degrees (for example, 375n is 37.5 degrees north); positions 5-9 define the longitude of the station with an accuracy of 0.1 degrees (for example: 1257e is 125.7 degrees east; 0025w is 2.5 degrees west).

Following the key (station, year, month), the record contains 31 rows, 115 bytes long, containing data for the corresponding day of the month (the first row is the first day, the second row is the second day, etc.). When describing each meteorological element, its position in the data row for the corresponding day is defined by the words "field position in row." The first two positions in each row are not used to record a special attribute, conventionally called "day." The "day" attribute can take the following values:

• 99, if there is no data in this row, i.e., data is missing for the i-th day (the i-th row serial number). This can be natural, for example, for February 30th, 31st, April 31st, etc. But it can also be the result of data being missing for some reason. It should be noted that, unfortunately, there are cases of false "data presence," i.e., cases where the "day" attribute has invalid values. For example, data for February 29th in non-yearly years. This is the result of a later-corrected defect in the archive generation software. Therefore, the user must maintain the "calendar" countdown;
• from 01 to 31, if the row contains data and has not been corrected. In this case, the "day" value corresponds to the day number in the month.

2. Description of Data Array Elements

2.1. Conventions Used in Describing Elements

The following conventions are used when describing record field formats:

• The D symbol denotes the field position in which a digit (DIGIT) is recorded;
• The C symbol denotes the field position in which an additional characteristic (COMPLEMENT) is recorded;
• The Q symbol denotes the position occupied by the quality characteristic (QUALITY);
• The S symbol denotes the position in which a numeric sign (SIGN) may be located;
• The Z symbol denotes the position in which insignificant zeros may be replaced by a space (ZERO). PL/1 notations are used to designate the formats of each field component;
• Q02 means that the quality characteristic takes the value Q=0 (the meteorological value is reliable) or Q=2 (the meteorological value is questionable);
• Q34 means that the quality characteristic takes the value Q=3 (the meteorological value is rejected) or Q=4 (no observations were conducted).

2.2. Relative Humidity

Relative humidity is the ratio of the elasticity of water vapor to the maximum elasticity at a given temperature, expressed as a percentage. At stations, relative humidity is determined using a psychrometer.

Table 2
Relative Humidity Recording Format

2.3. Water Vapor Pressure

Water vapor pressure is the main characteristic of air humidity, determined using a psychrometer; The partial pressure of water vapor contained in the air, expressed in hectopascals or millimeters of mercury, the same as air pressure.

Table 3
Water vapor pressure notation format

Note: Absolute humidity is sometimes referred to as water vapor pressure. At a temperature of 16°C, the numerical value of absolute humidity in g/m3 is equal to the numerical value of vapor pressure in mb. At other temperatures encountered in atmospheric conditions, their values ​​are quite close.

2.4. Atmospheric Pressure at Sea Level

Sea level pressure is the atmospheric pressure at mean sea level. This is either the pressure directly measured at sea level or the pressure measured at a location and reduced to sea level: it is calculated using the barometric formula based on the actual observed pressure and the air temperature of the atmospheric pressure that would exist at the station if it were located at sea level. Pressure at stations located above 800 m is not adjusted to sea level.

Table 4
Sea level pressure recording format

2.5. Moisture Deficit (Under-Saturation)

Moisture deficit is the difference between the saturated and actual vapor pressure of water at a given temperature and pressure. Moisture deficit is expressed in hectopascals or millimeters of mercury.

Table 5
Moisture deficit recording format

2.6. Wind Regularity Characteristics

Brief description: the wind can be steady or gusty, constant or changing direction.

A wind is considered steady if its speed remains more or less constant over the observation period (2 minutes); if its speed changes sharply, the wind is gusty.

Wind direction is considered constant if it remains within one compass point over the observation period (2 minutes); if the direction changes by more than 1 compass point, the wind is variable.

Both strong and weak winds can equally be gusty or steady, variable or constant.

Table 6
Wind Regularity Characteristic Recording Format

Table 7
Coding of wind regularity characteristics

2.7. Barometric Pressure Characteristics

The barometric pressure characteristic is determined by the barograph curve recording over a three-hour period. The curve's appearance can be used to determine whether the pressure is falling or rising.

Table 8
Barometric Pressure Characteristics Recording Format

Table 9
Rules for encoding the pressure trend characteristic

2.8. Magnitude of Barometric Tendency

The magnitude of the barometric tendency is calculated as the difference between two mercury barometer readings recorded at the time of observation and three hours before. If the pressure at the time of observation was greater than the pressure three hours before, the barometric tendency is considered positive (the pressure was increasing); If less, then negative (pressure dropped).

Table 10
Pressure trend value recording format

To obtain the pressure trend value from the data provided in the archive, concatenation must be performed.

PPP = C !! KK

In this case, PPP will have the format PIC'99V9'.
The archive authors used the C field to place the "tens" section, i.e.

If PPP <= 9.9, then D1 = 0;
If PPP > 9.9, then D1 = 1.

Attention! The archive's authors noted the following exceptions to this rule:

If "year" = 953 (1953), then with PPP=9.9, 10.1 is entered into the archive.

2.9. Horizontal Visibility

Horizontal visibility is the greatest distance from which, during daylight hours, a completely black object of sufficiently large angular dimensions (greater than 15 arc minutes) can be distinguished against the sky near the horizon, while at night, an unfocused light source of a certain intensity becomes indistinguishable. This assumes that the object is always geometrically observable.

The magnitude of horizontal visibility depends on atmospheric phenomena. In fog, it can decrease to almost zero, while in Arctic air it can reach hundreds of kilometers.

Horizontal visibility is measured both instrumentally and visually.

Table 11
Horizontal visibility recording format

Table 12
Coding of meteorological visibility in the horizontal direction (visibility)

2.10. Cloud Base Altitude

Cloud base altitude is the height of the cloud base above the station level. The cloud base altitude is determined for low-level clouds and for middle-level clouds if they are located no higher than 2500 m above station level.

Table 13
Cloud Base Altitude Recording Format

Table 14
Cloud base height encoding

2.11. Dew Point Temperature

Dew point is the temperature at which air reaches saturation (relative to water) at a given water vapor content and constant pressure. It is determined using a psychrometer. At relative humidity less than 100%, the dew point is always lower than the actual air temperature; The lower the relative humidity, the greater the difference between these temperatures. Therefore, to bring the air temperature to the dew point, the air must be cooled.

Table 15
Dew point entry format.

2.12. Soil Surface Condition

Soil surface condition is a characteristic of the terrain adjacent to a meteorological site; it is assessed visually by an observer daily at times closest to 8:00 a.m. and 8:00 p.m. of the station's standard time zone. It indicates whether the soil is dry, moist, wet, etc. (See Table 17)

Table 16
Soil surface condition recording format

Table 17
Soil surface condition coding.

2.13. Total Cloud Cover

The total cloud cover across the entire visible sky is estimated visually using a 10-point scale. The parts of the sky covered by clouds of all types are mentally added up. Gaps between individual cloud elements, which are typical for certain cloud forms (e.g., cirrus, altocumulus, and stratocumulus), are not subject to summation.

Table 18
Total cloud cover amount recording format.

Table 19
Total Cloud Cover Coding

Note: When the sky is not visible or the cloud cover cannot be determined, it can only be determined indirectly using the "8" cloud cover code.

2.14. Low Cloud Amount

The low cloud cover across the entire visible sky is estimated visually using a 10-point scale. The cloud-covered portions of the sky are mentally added up. Gaps between individual cloud elements, which are typical for certain cloud forms (e.g., stratocumulus, cumulus, and cumulonimbus), are not subject to summation.

Table 20
Low-level cloud amount entry format

Table 21
Low Cloud Amount Coding

2.15. Wind Direction

Wind is the movement of air relative to the Earth's surface. This movement is usually measured horizontally, which is what is determined using station instruments. The driving force of wind is the pressure gradient. Wind direction is the direction from which the wind blows. It is expressed in points relative to the horizon. Wind direction is determined at a height of 10-12 meters above the ground using station instruments.

Table 22
Wind direction recording format

Note: When rejecting wind direction and speed values, the "wind regularity characteristic" is also rejected. (See Section 2.5.)

Table 23
Wind Direction Coding Rules

2.16. Wind Speed

Wind speed is the distance air particles travel per unit of time. Wind speed at weather stations is measured at an altitude of 10-12 meters above the ground using station instruments.

Table 24
Wind Speed ​​Recording Format

Note: When rejecting wind speed and direction values, the "wind regularity characteristic" is also rejected. (See Section 2.5.)

2.17. Precipitation Amount

Precipitation amount is determined by the height (in millimeters) of the water layer formed on a horizontal surface by precipitation in the absence of runoff, infiltration, and evaporation. The receiving surface of the precipitation measuring device is located two meters above the ground and snow cover and is strictly horizontal. Precipitation is measured to tenths of a mm, at 3:00 a.m. and 3:00 p.m. Moscow time, as well as at times closest to 8:00 a.m. and 8:00 p.m. Moscow time, according to the time zone in which the station is located.

Table 25
Precipitation Recording Format

2.18. Atmospheric Pressure at Station Level

Atmospheric pressure is the hydrostatic pressure of the atmospheric column, caused by the weight of all the overlying layers of air. Atmospheric pressure at station level is measured using a station mercury cup barometer.

Table 26
Station-Level Pressure Recording Format

2.19. Soil Surface Temperature

Soil surface temperature observations are conducted on a level, sun-exposed, and vegetation-free area. Once snow cover has established, thermometers are placed on the snow surface and the temperature of the snow cover is measured. On the MT, temperature is recorded in whole degrees Celsius.

Table 27
Soil surface temperature recording format

Note: When the soil surface temperature is below -36 degrees Celsius, the minimum thermometer reading is taken.

2.20. Weather at the time of observation (current weather)

The general weather conditions are monitored continuously. Current weather is the conventional name for information about weather phenomena, coded in meteorological telegrams under the WW code heading, observed during the observation period or during the last hour.

Table 28
Current weather recording format

Table 29
Weather Coding at the Time of Observation

2.21. Weather between observation periods (past weather)

The general weather conditions are observed continuously. Past weather is the conventional name for information about weather phenomena transmitted in meteorological telegrams under the heading W, observed during the period between the last two observation periods (current and previous).

Table 30
Past weather recording format

2.22. Air Temperature

Air temperature is measured with a mercury thermometer installed 2 m above the soil or snow surface, away from living quarters, protected from direct and solar radiation, and well ventilated.

Table 32
Air Temperature Recording Format

2.23. Atmospheric Phenomena (AP)

This archive records APs observed only during a period of time, where the period is defined as a 30-minute interval (15 minutes before and 15 minutes after the full hour). For a period of 7:00 p.m., for example, the time from 6:45 p.m. to 7:15 p.m. is considered. APs are observed visually, and their intensity is also estimated visually. The intensity of speech is divided into weak, moderate, and strong.

Table 33
Groups AP recording format

Continuation of Table 33

Situation of groups AP 1 - 7

2.24. Cloud Shape

Cloud observations also include determining their shape. Depending on the altitude of their base, clouds are divided into three tiers:

1. High-level clouds; their base lies above 6,000 m - these are cirrus (Ci), cirrocumulus (Cc), and cirrostratus (Cs) clouds.
2. Middle-level clouds; their base lies between 2,000 and 6,000 m - these are altocumulus (Ac) and altostratus (As) clouds.
3. Low-level clouds; Their lower boundary is located below 2000 m and can begin at the ground surface - these are stratocumulus (Sc), stratus (SC), nimbostratus (Ns), cumulus (Cu), and cumulonimbus (Cb) clouds.

When determining cloud shapes, it is necessary to refer to the "Cloud Atlas", taking into account their similarity to one of the atlas photographs.

Table 34
Cloud form code and recording format

Continued from Table 34