The specification for oceanographic survey－Marine hydrographic observations
Some standard content:
National Standard of the People's Republic of China
Specification for oceanographic survey
Marine hydrographic observations
The specification for oceanographic surveyMarine hydrographic observationsSubject content and scope of application
GB 12763.2—91
This standard specifies the technical requirements, observation methods and the compilation method of observation records for ocean hydrographic observations. This standard is applicable to ocean hydrographic observations in the investigation of basic elements of the marine environment. 2 Reference standards
General rules for marine survey
GB I2763.1
G 12763.3
Marine survey specification
Marine meteorological observation
GB 12763. 7
3 Technical design
Marine fragrance specification Marine survey data processing Part 1 I
General provisions
After receiving the task letter or contract, the unit undertaking the task must carry out technical design according to the requirements of the task letter or contract. The contents of the technical design include:
The scope of the tour area and the layout of observation stations
Observation items and quality requirements of observation data; Observation methods and timing;
Requirements for survey ships and their main equipment: the names and quantities of the main observation instruments;
Survey results to be submitted and the completion time. 4 Observation items, methods and sequence
4.1 Observation items
Observation items generally include: depth, water temperature, salinity, ocean currents, waves, transparency, water color, sea luminescence and sea ice. If conditions permit, observations should also be made (see Appendix D). The specific observation items for each survey should be clearly specified in the technical design. 4.2 Observation methods
Hydrological observations shall be carried out in the following ways:
Large-area observations:
b. Cross-sectional observation:
Continuous observation:
Approved by the State Administration of Technical Supervision on 1991-03-22 and implemented on January 1, 1992
d. Synchronous observation.
4.3 Observation sequence
Hydrological observation is generally carried out in the following sequence: station position and water depth:
current and water level:
water temperature and salinity
d. Waves,
transparency, water color and luminescence;
sea luminescence.
5 Principles of station layout and determination of observation time GB 12763.2-91
5.1 The stations to be laid out should be representative in the observed sea area, that is, the hydrological element data measured can reflect the distribution characteristics and change laws of the element.
5.2 Each hydrological section should have no less than three stations. The observation work of each station on the same section should be completed in the shortest possible time. The setting direction of the hydrological section should be perpendicular to the dominant ocean current passing through the observation area as much as possible. 5.3 The distance between two adjacent stations should not be greater than half of the spatial scale of the ocean process being studied. 5.4 Within the time scale of the ocean process being studied, the number of observations at each station should be no less than two. 6 Station positioning and observation time standard
The positioning accuracy of the station and the time standard of observation shall be implemented in accordance with the relevant provisions of GB12763.1. 7 Basic requirements for the selection of hydrological observation instruments
7.1 The selection of hydrological observation instruments must comply with the relevant provisions of GB 12763.1. 7.2 The applicable water depth range and measurement range of the instrument must meet the water depth variation range of the observation area and the variation range of the measured elements, and at the same time, it must meet the requirements for the accuracy and temporal and spatial continuity of the observation elements and their calculation parameters. 7.3 The selected instrument must be suitable for the carrier and observation method used. The recording method of the instrument should be convenient for data processing and further processing.
7.4 The basic requirements for the installation location of survey equipment are: it is convenient for operation, does not interfere with other work, and prevents buildings, radiant heat and sewage discharged from ships from affecting the observation results.
7.5 After each voyage of observation, the survey equipment and observation instruments should be carefully maintained. All instruments that have been exposed to water must be washed with fresh water and dried for ten days before preservation. Winch, wire rope and counter, etc. should be carefully wiped and greased before preservation. 8 General requirements for recording, sorting and acceptance of observation data 8.1 The original observation data shall be recorded in accordance with the relevant provisions of GB12763.1. 8.2 The observation data shall be sorted in accordance with the report and magnetic record format in GB 12763.7. 8.3 The observation results shall be accepted by the task issuing unit or the entrusting unit according to the quality requirements specified in the task book or contract. Part II Depth Measurement
9 Terminology
9.1 On-site water depth
refers to the vertical distance from the white sea surface to the seabed measured on site. It is different from the water depth from the reference surface marked on the nautical chart. The purpose of measurement is to determine the observation level.
9.2 Instrument wash depth
GB 12763. 2-91
Refers to the vertical distance from the sea surface to the underwater observation instrument during measurement. The purpose of measurement is to determine the depth of the measured hydrological element value. 10. Technical requirements
10. 1 Measurement accuracy
The accuracy of the depth dial is ±2%. For shallower than 100m, record the decimal place; for more than 100m, record the integer. 10-2 Measurement time
For large-scale or cross-section stations, the ship will measure once when it arrives at the station; for continuous stations, the measurement will be once every hour. 11 Measurement method
11.1 Water depth measurement
11.1.1 Water depth is usually measured by echo sounder. When using echo sounder to measure water depth continuously, the continuous working time specified by the instrument shall not be exceeded.
11.1.2 When the water depth is not more than 100m, the water depth can also be measured by wire rope sounding method. Before measurement, the correction coefficient of the counter should be obtained first, so as to make instrument error correction for the wire rope. When measuring, the wire rope is tilted, and the inclination of the wire rope should be measured by the inclination meter. When the inclination exceeds 10, the inclination of the wire rope should be corrected: when the inclination exceeds 30°, the weight of the plumb bob should be increased or the side push on the ship should be used to control the inclination within 30°:
11.2 Measurement of instrument sinking depth
The sinking depth of the instrument is usually measured by the depth sensor equipped with the instrument itself. However, when the predetermined depth of the instrument is not greater than 100m, the depth measurement can also be carried out in accordance with the method of wire rope sounding. If the wire rope sounding method has to be used to measure the depth of the instrument greater than 100m, it must be stated in the observation record sheet 1. 12 Arrangement of measurement records
12.1 Arrangement of echo sounder measurement records 12.1.1 The depth indicated or recorded by the sounder must be corrected for transducer draft, sound velocity deviation and rotation speed. The record sheet format should comply with the requirements of Table C1 in Appendix C. The calculation formula (1) for the measured depth is: = D, + + +
Where: D——measured depth, mr
D,—sounder reading m;
AD.--draft correction value, m;
—sound velocity deviation correction value, m;
rotation speed correction value, m.
12.1.2 The calculation formula for the correction value of transducer draft depth (2) is: Ah - H+ +(H. - H) -
Where: f
bow draft, m;
stern draft, m
0—horizontal distance from bow to transducer, m;
vertical distance from transducer working surface to keel edge, m. .....( 1)
12.1.3When the vertical average sound speed of the measuring station deviates from the design sound speed by ±7.5m/s, a sound speed deviation correction shall be made. The calculation formula (3) for the sound speed deviation correction value is:
GB 12763. 2
Wherein, —
the vertical average sound speed of the measuring station, m/s, which can be obtained by calculating the sound speed of each layer according to the sound speed formula of GB12763.7 based on historical or measured temperature, salinity and depth data and then taking the average;
the design sound speed of the depth sounder, m/s.
12.1.4When the actual rotation speed deviation of the depth sounder exceeds 1% of the design rotation speed, a rotation speed correction shall be made. The calculation formula (4) of the speed correction value is:
where n
-the actual speed of the depth sounder, r/min;
the design speed of the depth sounder, r/mn.
12.2 Theory of wire rope depth sounding records
12.2.1 The wire rope depth sounding records must be corrected by the counter error. The method for calculating the counter correction coefficient is as follows: a section of wire rope (about 100 Ⅱ) is released through the counter, and the length of the released wire rope is measured with a tape measure. The ratio of this length to the counter reading is the correction coefficient of the counter. If the inclination of the wire rope is within 1 during depth sounding, no inclination correction is required.The counter reading (the difference between the counter reading when the hammer reaches the seabed and the surface) multiplied by the correction coefficient of the counter will give the water depth value. 12.2.2 The correction of the inclination of the wire rope is divided into two parts: above water and underwater. The correction value of the above water part can be obtained from Table 1 by the height of the winch arm end from the plum surface and the inclination of the wire rope when the hammer reaches the seabed. There are two cases for the correction of the underwater part: when the ship is anchoring, the length of the paid-out rope is obtained by subtracting the actual length of the rope above water from the counter reading after the instrument error correction. The underwater correction value is obtained by looking up the length of the paid-out rope and the inclination of the wire rope in Table 2. The actual water depth is obtained by subtracting the underwater correction value from the length of the paid-out rope. When the ship is drifting, the underwater correction value is obtained by looking up the length of the paid-out rope and the inclination of the wire rope in Table 3. Then the actual water depth is obtained by subtracting the underwater correction value from the length of the paid-out rope. The format of the record sheet should meet the requirements of Table C2 in Appendix C.
Table 1 Correction value of the above-water part when the wire rope is inclined Wire rope inclination angle
Released rope length
Height of winch arm end from sea surface
Correction value of the underwater part of the wire rope when the ship is anchored and sounding the depth
Release rope length
Release rope length
GB 12763. 2—91
Continued Table 2
Myanmar Cape
Table 3 Correction value of underwater part of wire rope inclination during vessel drifting soundingWire rope
12.3 Arrangement of instrument sinking depth measurement records 15
12.3.1 For observation instruments equipped with depth sensors, the arrangement method of sinking depth measurement records shall be carried out according to the type and recording method of the sensor used.
12.3.2 When determining the sinking depth of the instrument based on the length of the wire rope paid out and the inclination of the wire rope, if only one instrument is hung on the wire rope, the arrangement method of its sinking depth measurement records shall refer to the arrangement method of wire rope sounding records. When a wire rope is hung with an instrument, the actual sinking depth of each instrument can be obtained according to the counter readings at the depth of each instrument (the difference between the counter readings when the instrument reaches the depth and when it reaches the surface), after the counter error correction, the stop of the upper and lower parts of the wire rope when it is inclined. The third swallow
13Terms
refers to the seawater overflow measured under field conditions. 14Technical requirements
14.1Accuracy of water temperature observation
The accuracy of water temperature observation is listed in Table 4.
Accuracy level
14.2Observation time
GB 12763. 2 -91
Table 4Accuracy of water temperature observation
Accuracy
For large-scale or cross-sectional measurement stations, the ship arrives at the station for observation times; for continuous measurement stations, observations are generally made once every two hours. 14.3 Standard layers for water temperature observation
Resolution
The standard layers for water temperature observation are shown in Figure 5, where the surface layer refers to the water layer within 1 meter below the sea surface. The bottom layer is defined as follows: when the water depth is less than 50m, the bottom layer is the water layer 2m from the bottom; when the water depth is within the range of 50-200m, the distance from the bottom to the bottom is 4% of the water depth; when the water depth exceeds 200m, the distance from the bottom to the bottom is determined by comprehensive consideration of the water depth measurement error, wave conditions, ship drift conditions and seabed topography characteristics, and is kept as close to the seabed as possible while ensuring that the instrument does not touch the bottom. Table 5 Standard levels for water temperature observation
Water depth range
Standard levels for water temperature observation
Surface layer, 5.10, 15, 20.25, center, 50, 75.100, 125, 150, bottom layer, 10, 20, 30, 50, 75, 100, 125, 150, 200, 250.300.400, 500, 600, 700, 800.1000.1200, 1500.2000, 2500, 3000 ( When the water depth is greater than 3000m, add one layer for every meter), the bottom layer 14.4 Minimum distance between the bottom layer and the adjacent standard layer When the water depth is less than 50m, the minimum distance between the bottom layer and the adjacent standard layer is stipulated as 2 meters; when the water depth is within the range of 50-100m, the minimum distance is stipulated as 5 meters; when the water depth is within the range of 100-200m, the minimum distance is stipulated as 10 meters; when the water depth exceeds 200m, the minimum distance is stipulated as 25 meters. When the distance between the bottom layer and the adjacent standard layer is less than the specified minimum distance, the pseudo-standard layer close to the bottom layer can be avoided. 15 Observation method
15.1 Vertical continuous observation of water temperature
15.1.1 The vertical continuous change of water temperature can be measured by using the temperature-depth system. Commonly used instruments include temperature, salinity and depth instrument (abbreviated as CED or STD), electric temperature and depth instrument (abbreviated as FBT) and throwable temperature and depth instrument (abbreviated as XRT). When using the temperature and depth system to measure water temperature, at least one relatively uniform water layer should be selected every day to compare with the measurement results of the temperature meter. If it is found that the measurement results of the temperature and depth system do not meet the required accuracy, the instrument zero point should be adjusted or the instrument probe should be replaced, and the comparison results should be recorded in the measurement duty log. 15.1.2 Observations should be carried out on the windward side of the ship to prevent cables or wire ropes from entering the bottom of the ship. If they are pressed into the bottom of the ship, measures should be taken immediately. The observation position should avoid the engine room sewage outlet and other pollution sources. 15.1.3 Determine the lowering depth of the probe according to the on-site water depth. The lowering speed of the temperature, salinity and depth instrument probe should generally be controlled within the range of 0.5~1.0m/s, and it should remain unchanged during one observation. If the ship is shaking violently, a larger descent speed should be selected to avoid more depth (or pressure) inversion phenomena in the observation data.
15.1.4 The probe should be placed in a cool place and should not be exposed to the sun. If the probe is overheated or the sea temperature is high, the probe should be placed in the water for a few minutes before observation. When the water is calm, observe immediately after the probe is in the water; when the wind and waves are strong, wait until the probe reaches a depth of several meters before starting observation. 15.1.5 For a temperature, salinity and depth meter with real-time display, the depth (or pressure) value of the probe when it is on the water surface should be recorded before observation. For a self-contained temperature, salinity and depth meter, it should be confirmed according to the sampling interval that at least one set of data has been recorded on the water surface before it can be lowered to start observation. 15.1.6 The data obtained when the probe is lowered is the official measurement value, and the data obtained when the probe is raised is used as a reference value when processing water temperature data. 15.1.7 During the observation, the instrument model and serial number, the station number, station position and water depth, observation period, start time (time when the probe enters the water and starts to be lowered), end time (time when the probe reaches the bottom) and observation depth, data sampling interval, probe lowering speed, head replacement ascent speed (when obtaining ascent data) and probe out of water time (when obtaining ascent data) and ship drift should be recorded. 15.1.8 The acquired records, such as magnetic tapes, disks, solid state storage devices or recording curves, should be read or checked immediately. If missing data, out-of-band data or recording curves are found to be discontinuous and unclear, they should be re-measured immediately. If it is confirmed that the temperature measurement source drift of the probe is large, the temperature measurement system of the probe should be checked to find out the cause and eliminate the fault. 15.1.9 When using XIT for observation, the observation should be carried out at the speed specified by the technical performance of the instrument. 15.2 Observation of water temperature of standard layer
The water temperature of standard layer can be obtained by interpolation of adjacent observation values above and below the standard layer measured by temperature-depth system. It can also be measured by inverted temperature table. The method of observing seawater temperature by inverted temperature table and the method of collating observation records shall meet the requirements of Appendix A. 16 Collation of observation records
16.1 Collation of observation records of temperature-depth system
16.1.1 Depth (or pressure) and water temperature measured values must be corrected according to the calibration results. 16.1.2 Delete the depth value (or pressure value) and its corresponding water temperature data of depth (or pressure) inversion in the original water temperature observation record, and establish a water temperature sequence with increasing depth (or pressure). 16.t.3 Determine the "abnormal value" in the water temperature data sequence. For water temperature, the judgment formula (5) is as follows: [Tx Tr-1il/(Dk — Dx-1) A7e Where: Tx is the water temperature value to be determined at the depth (or pressure) D, C+Tr-[--\--the water temperature value at the previous depth (or pressure) ;AT. A quality control coefficient, depending on the maximum water temperature gradient that may occur in the observed sea area, C/m city/kPa. If the above formula is established, Tk is considered to be an unreasonable record value, and T and the value are deleted. 16.1.4 If the measured pressure needs to be converted into depth, it should be calculated according to formula (6): 2-+++r+%
g()+rp
Where: 2-depth, m
ppressure, kPa
9(Pa)=9.780318(1.0+5.2788×10-sin—2.36×10-5sin*), is the gravity acceleration that varies with latitude, m/s3;
=2.184×10-7, is the average vertical gradient of gravity, m/(s2-kFa); - is the gravity potential deviation, m=/s, where
=[(s,t,p）-V(35,o,P), is the specific volume deviation C = 9.72659×10-#;
C, ——2.251 2X10-7
Gg =2. 279X 10-*,
C, = - 1. 82X10-19,
16.1.5 For water temperature data with a fast sampling rate and more than two samplings per meter interval, the water temperature data should be smoothed according to the predetermined depth (or pressure) interval to obtain a water temperature data series with equal depth (or pressure) intervals. For example, the water temperature measurement values between 1 and 3 m are summed and averaged to obtain the water temperature value at 2 m: in this way, the water temperature data series with equal depth intervals of 2, 4, 6, and 8 m are obtained. 16.1.6 For water temperature data series with a slow sampling rate and a sampling interval of more than 1m, if you want to obtain water temperature data of equal depth intervals, you can interpolate to obtain it.
16.1.7 For water temperature data of water temperature observation series that have been corrected for time lag, the above processing should use the corrected water temperature data series.
16.7.8 When the original record is given in the form of a temperature-depth curve, the temperature-depth curve can be continuously read using a digitizing device. The digitized temperature-depth data can be used to give the water temperature values of equal depth intervals or standard layers according to the above method. If the reader is used for manual reading, only the temperature and depth values of the standard layer are read. When reading the values, the "abnormal values" on the curve should be discarded. When there are overlapping layers on the recording curve, some characteristic points of the thermocline should be read, such as the temperature and depth values of the upper and lower boundaries of the thermocline and some inflection points in the middle. Part 4 Salinity Measurement
17 Terminology
17.1 Absolute Salinity
The ratio of the mass of solutes in seawater to the mass of seawater is called absolute salinity. Since absolute salinity cannot be measured directly, practical salinity is defined. 17.2 Practical Salinity
Practical salinity is determined by formula (7):
S=a +a+ais +ak+ +
where
Practical salinity:
When the temperature is 15°C. The ratio of the conductivity of a seawater sample at standard atmospheric pressure to the conductivity of a potassium chloride solution with a mass-to-basis ratio of 32.435 6×10-\ at the same temperature and pressure; n - 0.008 0;
= = -0.169 2;
dg -25.385 1;
as - 14.094 1;
+ - - 7.026 1;
ab =2.708,
When K15 is exactly equal to 1, the practical salinity of the seawater sample is exactly equal to 35, that is, 24:=35.0000. The applicable salinity range of formula (7) is: 2 S 42
18 Technical requirements
18.1 Accuracy of salinity measurement
The accuracy of salinity measurement is listed in Table 6.
Table 6 Accuracy of salinity measurement
Accuracy level
18.2 Observation time
Accuracy
Resolution
Salinity and water temperature are observed simultaneously. For large-area or cross-sectional stations, the ship observes once at the station; for continuous stations, the observation is generally once every two hours. 18.3 Standard layer for salinity measurement
The standard layer for salinity measurement and other relevant provisions are the same as those for temperature, see 14.3 to 14.4. 19 Measurement method
19.1 Measuring salinity using a field temperature-disk-depth meter 19.1.1 The vertical continuous change of salinity can be measured using a field temperature-salinity-depth meter. For the measurement method, refer to 15.1.2~15.1.8. 19.1.2 When using a temperature-salinity-depth instrument to measure salinity, at least one relatively uniform water layer should be selected every day and compared with the measurement results of seawater samples using a laboratory salinity meter. If it is found that the measurement results of the temperature-salinity-depth instrument do not meet the required accuracy, the instrument zero point should be adjusted or the instrument probe should be replaced. The comparison results should be recorded in the observation duty log. GB 12763-2--91
19.1.3 The conductivity sensor of the temperature-salinity-depth instrument must be kept clean. After each observation, it must be rinsed with distilled water (or deionized water) without leaving any salt particles or dirt:
19.2 Using a laboratory salinometer to measure the salinity of seawater samples 19.2.1 When using an electrode or induction laboratory salinometer to measure the salinity of a water sample, it must be calibrated first to obtain the calibration value of the standard seawater conductivity ratio at temperature T (C) and then adjust the calibration value to each level of the sample reading. Repeat the adjustment of the positioning calibration level so that the final phase difference between the two readings is within 3 and the calibration is completed. When measuring seawater samples, the positioning calibration knobs are not changed. 19.2.2 When measuring seawater samples, first inject the seawater sample into the conductivity cell, start the stirrer to stir for 1~2 minutes, then measure the temperature of the seawater sample, adjust the R knobs to make the meter pointer approach zero, and read the R value. If the reading is suspicious, it must be re-measured until the data is considered reasonable. The measured seawater sample temperature and value shall be recorded in the salinity analysis record sheet 1. The record sheet format is shown in Table C10 of Appendix C. 19.2.3 When measuring continuously, standard seawater shall be used for calibration at least once a day. Calibration and measurement shall not be carried out without stirring, and bubbles and other floating objects are not allowed in the conductivity cell. 19.2.4 The temperature of the seawater sample to be measured shall be close to that of the standard seawater before measurement. The induction type salinometer requires that the difference between the two should be within 2°C; the electrode type salinometer requires that the stirrer should be started for 1 to 2 minutes before the two temperatures are basically equal. 19.2.5 After the work is completed, the conductivity cell must be cleaned with distilled water. The electrode type salinometer must be filled with distilled water in the conductivity cell to protect the electrode.
20 Arrangement of measurement records
20.1 Arrangement of salinity records measured by on-site salt depth meter 20.1.7 The salinity records measured by the temperature-salinity depth meter shall be arranged in accordance with 16.1.1 to 16.1.7. 20.1.2 If the measured values are conductivity, temperature and pressure, the conductivity shall be converted into salinity with the help of the practical salinity calculation formula. The practical salinity calculation formula (8) is:
=a +a + aR ++ a as
T— 15
+1+ K(T-15)
Eho h +b2 +b + +hR\]
Wherein: R is the ratio of the conductivity of the tested seawater sample to the standard seawater sample with a practical salinity of 35 at the same temperature and a standard atmospheric pressure;
T is the temperature of the tested seawater sample, ℃
t = 0. 000 5
b: -0. 005 6;
b = — 0. 006 6 :
ta=--0.037 5,
h, -0. 063 6 :
K =0.016 2.
The values of ota+a and as are the same as in formula (7).
The conductivity ratio can include the conductivity, temperature and pressure values measured on site, and is calculated by formula (9): R
where: n
The ratio of the conductivity measured on site to the conductivity of the standard seawater at %=35, T=15℃+=0: Here, - the ratio of the conductivity measured on site to the conductivity of the same sample under the same temperature and =0 conditions; - the ratio of the conductivity of reference seawater with a practical benefit of 35 at temperature T (C) to its conductivity at 15C. R. can be calculated by the following formula:
GB 12763. 2--- 91
(A +AP + A)
R, =1+I+RT+BP+ (B + B/T)R
Pressure measured on site, kPa;
T—seawater temperature measured on site, ℃
R—ratio of conductivity measured on site to standard seawater conductivity of 8-35.T=15,=0;41 =2. 070X10-5 :
Ag ---6. 370X10-12
As =3. 989X 10: 11 ,
B, = 3. 426X10-*:
H =4. 464X10-1;
B3 -4. 215×10-1;
B, =-3. 107X 10 *.
The calculation formula is
= G + CT +C+CT + CT
Wherein, T is the seawater temperature measured on site, Co = 0. 676 609 7,
G, 2. 005 64 × 10- ;
C2 =1. 104 259×10-4;
Cs =-6. 969 8X10-\,
G, =1. 003 1x.10-
The above formulas (8), (9) and (11) are valid in the temperature range of -2 to 35°C, pressure of 0 to 10°kPa and practical salinity of 2 to 42. 20.1.3 After the measured conductivity value is converted into salinity, if there is an obvious "abnormal peak" in the layer other than 1, the conductivity or temperature measurement value should be corrected after time, and then the salinity should be recalculated. 20.2 Arrangement of records of salinity of water samples measured by laboratory salinometer When the salinity of seawater samples is measured by laboratory salinometer, the salinity 5 value can be calculated by formula (8) based on the measured conductivity ratio R value and the temperature T value of the seawater sample; the measured conductivity ratio and the temperature of the seawater sample can also be used to look up the international oceanography commonly used table to obtain S (uncorrected value) and S value, and then the two are added to obtain the salinity value, S=S+AS. Part V Ocean Current Observation
21 Terminology
21.1 Current
The macroscopic flow of seawater is called ocean current, which is characterized by velocity and direction. 21.2 Velocity
The distance that seawater flows per unit time is called velocity. 21.3 Direction
The direction in which seawater flows is called direction. True north is zero and measurement is clockwise. 22 Technical Requirements
22.1 Quantities to be measured
The main quantities to be measured are velocity and direction: the auxiliary quantities to be measured are wind speed and direction. The measurement of auxiliary quantities shall comply with the relevant provisions of GB12763.3.
22.2 Accuracy of measurement
GB12763.2--91
22.2.1 The velocity and direction values of ocean current observation are specified as the average velocity and mainstream direction of 3 minutes. If the observed value of the current velocity is not the average value of 3 minutes, the sampling period should be stated in the observation record. 22.2.2 When the current velocity is not more than 100m/g, the accuracy of current velocity measurement in the sea area with a water depth of less than 200m is ±5cm/s; in the sea area with a water depth of more than 200m, the accuracy of current velocity measurement is ±3cm/s. The accuracy of current direction measurement is ±10°22.2.3 When the current velocity exceeds 100m/s, the accuracy of current velocity measurement in the sea area with a water depth of less than 200m is ±5%; in the sea area with a water depth of more than 200m, the accuracy of current velocity measurement is ±3%. The accuracy of current direction measurement is ±10°. 22.3 Observation level
Refer to: Table 5 (see Article 14.3), select according to needs. However, the surface layer for current observation is stipulated as the water layer within 3m. 22.4 Continuous observation time and frequency The continuous observation time of ocean currents should be no less than 25 hours, with a minimum observation rate of times per hour. For tide forecasting stations, continuous observation should generally be no less than one week in accordance with good astronomical conditions. 23 Standard Observation Methods
23.1 When observing shallow ocean currents (water layers within three times the draft of the ship), observations should be made with the aid of small anchored buoys and small boats. 23.2 When using survey vessels as carriers to measure ocean currents below the shallow layer, non-self-recording current meters can be used for observation after the current meter is sunk to the predetermined observation water layer. + Self-recording current meters can be used to string together multiple current meters to measure multiple layers of ocean currents at the same time according to the load of the winch and wire rope. The start and end times of observations must be recorded when measuring currents. 23.3 When using self-recording current meters to observe ocean currents with the aid of buoys or submerged buoys, the vessels that deploy and recover buoys (or submerged buoys) must be equipped with special lifting equipment. After the buoy (or submerged buoy) is located, record the start time of observation and the position of the buoy (or submerged buoy). At the end of observation, record the end time of observation before recovering the buoy (or submerged buoy). Question: The flashing device on the buoy or submerged buoy must be truly watertight to ensure normal and continuous flashing. 23.4 When measuring currents in the deep sea, if it is difficult for the ship to drop anchor and the current velocity in the deep layer is indeed very small, the "dual machine method" can be used for observation, that is, on the source-moving ship, one current meter is placed in the predetermined observation water layer, and the other current meter is sunk in the "no current layer". The vector basis difference of the observation results of the two layers of current meters is the current observation value of the predetermined observation layer. www.bzxz.net
23.5 When the inclination angle of the wire rope or cable for placing the current meter exceeds 10°, the inclination angle should be corrected. The correction method is shown in Article 12.2.2. 23.6 When using a ship as a carrier for continuous current observation, the ship's position should be observed once an hour. If it is found that the ship is seriously wrong (exceeding the positioning accuracy requirement), it should be moved to the original position and the observation should be restarted. 23.7 Continuous observations around the mouth should generally not be missed. Anyone who interrupts the observation for more than two hours must repeat the observation. Start observation again. 24 Arrangement of observation records
24.1 When measuring current using a current meter with digital display, recording paper tape or direct reading, the measured data should be arranged according to the method and procedure required by the technical performance of the instrument to obtain the actual current velocity and true current direction. 24.2 When measuring current using an automatic current meter with tape recording, the recording tape can directly print out the current velocity and current direction values through a player and printer.
Chapter 6 Wave Observation
25 Terminology
25.1 Waves
Wind waves and swells appearing on the sea are collectively referred to as waves. Waves generated under the direct action of wind are called wind waves; waves from other sea areas, or waves left after the local wind force decreases sharply, the wind direction changes or the wind calms down, are all called swells. 25.2 Wave height
The vertical distance between adjacent wave crests and troughs is called wave height. In the continuous record of sea waves, the average of the individual wave heights of one third of the total number of wave heights is called the significant wave height.
25.3 Cycle
GE 12763.2—91
The time interval between two adjacent wave crests or two wave troughs passing through a fixed point is called a wave period. The average value of each wave period used to determine the significant wave height is called the significant wave period.
25.4 Interwave
The direction of the wave, with the north as zero and the direction measured clockwise. 25.5 Wave type
The appearance of the wave is called the wave type.
25.6 Sea state
The characteristics of the sea surface under the action of wind are called sea state. 26 Technical requirements
26.1 Quantities to be measured
The ten main quantities to be measured are wave height, period, wave direction, wave type and sea state; the auxiliary quantities to be measured are wind speed and wind direction. The observation of auxiliary quantities shall comply with the relevant provisions of GB12763.3
26.2 Accuracy of wave height, period and wave direction observation 26.2.1 The accuracy of effective height measured by instrument is ±10%, and the accuracy of effective period is ±0.5s. 26.2.2 The accuracy of effective wave height measured by instrument is ±15%, and the accuracy of effective wave period is ±0.5s: The accuracy of wave direction measured by compass azimuth (magnetic deviation correction must be performed when measuring wave direction by magnetic compass) is ±5°. 26.3 Observation time
For large-scale or cross-sectional stations, the ship shall observe once at the station; for continuous stations, the observation shall be traced back once every two hours, and the observation time is 02.05, 08, 11, 14, 17, 20, and 23 Beijing Standard Time. Daily measurements are only carried out during the day. 26.4 The length of time for recording the wave surface and the sampling time interval The wave surface recording instrument requires no less than 100 waves; the length of the recording time depends on the size of the effective wave period, generally 10 to 20 minutes, and the sampling time interval is 0.5s or 15.
26.5 Classification of wave types
According to the appearance characteristics of the waves, the wave types are divided into three categories: wind wave type, swell wave type and mixed wave type (see Table B1 in Appendix B). 26-6 Level of sea conditions
According to the shape of the wave crest, the degree of crest breakage and the number of waves, the sea conditions are divided into 10 levels (see Table B2 in Appendix B). 27 Current measurement methods
27.1 Observation of wave height and period
27.1.1 Measurement methods
27.1.1, 1 Shallow water wave measurement usually uses an easy-to-fix wave meter; deep water wave measurement generally uses a floating ball acceleration type wave meter. 27.1.1.2 The working mode of the ship (move or anchor) and the placement position of the probe shall be determined according to the wind and current. When the induction float is applied, the ship generally does not anchor, so that the float can be quickly separated from the hull. 27.1.1.3 The observation position should avoid obstacles that affect the waves, such as reefs, shoals, islands and artificial buildings. When there are obstacles near the measuring point, the conditions that affect the waves must be recorded. 27.1.1.4 When measuring waves in strong current areas, it is not advisable to use wave measurement that will cause errors such as drifting of wave records due to currents: when there is strong electrical interference near the measuring point, it is not advisable to use a remote wave meter.
27.1.2 Daily measurement method
27.1.2. When measuring the wave height and period daily, you should first look around the entire sea surface and pay attention to the distribution of wave height. Then measure the height and period of 10 significant waves (larger waves in the observed wave system) and take the average value, which is the effective slope height and its corresponding effective period. 27.1.2.2 When the wavelength is less than the length of the ship, the distance between the deck and the waterline can be used as a reference scale to measure the height and the distance between the two significant waves can be used as a reference scale to measure the effective slope height.2. Arrangement of salinity records of water samples measured by laboratory salinity meter When using laboratory salinity meter to measure the salinity of seawater samples, the salinity value 5 can be calculated by formula (8) based on the measured conductivity ratio R value and the temperature T value of the seawater sample; the measured conductivity ratio and the temperature of the seawater sample can also be used to look up the international oceanography common table to obtain S (uncorrected value) and S value, and then add the two to get the salinity value, S=S+AS. Part 5 Ocean Current Observation
21 Terminology
21.1 Current
The macroscopic flow of seawater is called ocean current, which is characterized by flow velocity and flow distance. 21.2 Flow velocity
The distance that seawater flows per unit time is called flow velocity. 21.3 Flow direction
The direction in which seawater flows is called flow distance. Due north is zero and measured clockwise. 22 Technical requirements
22.1 Quantities to be measured
The main quantities to be measured are velocity and direction; the auxiliary quantities to be measured are wind speed and direction. The measurement of auxiliary quantities shall comply with the relevant provisions of GB12763.3.
22.2 Accuracy of measurement
GB12763.2--91
22.2.1 The velocity and direction values of ocean current observations are specified as the average velocity and mainstream direction of 3 minutes. If the observed value of the velocity is not the average value of 3 minutes, the sampling period shall be stated in the observation record. 22.2.2 When the velocity is not greater than 100m/g, the accuracy of velocity measurement in sea areas with a water depth of less than 200m is ±5cm/s; in sea areas with a water depth of more than 200m, the accuracy of velocity measurement is ±3cm/s. The accuracy of current direction measurement is ±10°22.2.3 When the current velocity exceeds 100m/s, the accuracy of current velocity measurement is ±5% in the sea area with a water depth of less than 200m; the accuracy of current velocity measurement is ±3% in the sea area with a water depth of more than 200m. The accuracy of current direction measurement is ±10°. 22.3 Observation level
Refer to: Table 5 (see Article 14.3), select according to needs. However, the surface layer of ocean current observation is stipulated as the water layer within 3m. 22.4 Continuous observation time and frequency The length of continuous observation of ocean current should be no less than 25h, and the observation rate should be at least times per hour. The observation station for forecasting tidal currents should generally be no less than a week of continuous observation in accordance with good astronomical conditions. 23 Standard observation methods
23.1 When observing shallow ocean currents (water layer within three times the draft of the ship), small anchored buoys and small boats should be used for observation. 23.2 When using a survey vessel as a carrier to measure the currents in various layers below the shallow layer, if it is not a self-recording current meter, the observation can be carried out after the current meter is sunk to the predetermined observation water layer. + self-recording current meter, according to the load of the winch and wire rope, multiple current meters can be strung together to measure multiple layers of currents at the same time. The start time and end time of the observation must be recorded when measuring the current. 23.3 When using a self-recording current meter to observe the current with the help of a buoy or a submerged buoy, the vessel that launches and recovers the buoy (or submerged buoy) must have a special lifting device. After the buoy (or submerged buoy) is located, record the start time of the observation and the position of the buoy (or submerged buoy). After the observation, record the end time of the observation before recovering the buoy (or submerged buoy). Question: The flashing device on the buoy or submerged buoy must be truly watertight to ensure normal and continuous flashing. 23.4 When measuring currents in the deep sea, if it is difficult for the ship to drop anchor and the current velocity in the deep layer is indeed very small, the "dual machine method" can be used for observation, that is, on the source-moving ship, one current meter is placed in the predetermined observation water layer, and the other current meter is sunk in the "no current layer". The vector basis difference of the observation results of the two layers of current meters is the current observation value of the predetermined observation layer.
23.5 When the inclination angle of the wire rope or cable for placing the current meter exceeds 10°, the inclination angle should be corrected. The correction method is shown in Article 12.2.2. 23.6 When using a ship as a carrier for continuous current observation, the ship's position should be observed once an hour. If it is found that the ship is seriously wrong (exceeding the positioning accuracy requirement), it should be moved to the original position and the observation should be restarted. 23.7 Continuous observations around the mouth should generally not be missed. Anyone who interrupts the observation for more than two hours must repeat the observation. Start observation again. 24 Arrangement of observation records
24.1 When measuring current using a current meter with digital display, recording paper tape or direct reading, the measured data should be arranged according to the method and procedure required by the technical performance of the instrument to obtain the actual current velocity and true current direction. 24.2 When measuring current using an automatic current meter with tape recording, the recording tape can directly print out the current velocity and current direction values through a player and printer.
Chapter 6 Wave Observation
25 Terminology
25.1 Waves
Wind waves and swells appearing on the sea are collectively referred to as waves. Waves generated under the direct action of wind are called wind waves; waves from other sea areas, or waves left after the local wind force decreases sharply, the wind direction changes or the wind calms down, are all called swells. 25.2 Wave height
The vertical distance between adjacent wave crests and troughs is called wave height. In the continuous record of sea waves, the average of the individual wave heights of one third of the total number of wave heights is called the significant wave height.
25.3 Cycle
GE 12763.2—91
The time interval between two adjacent wave crests or two wave troughs passing through a fixed point is called a wave period. The average value of each wave period used to determine the significant wave height is called the significant wave period.
25.4 Interwave
The direction of the wave, with the north as zero and the direction measured clockwise. 25.5 Wave type
The appearance of the wave is called the wave type.
25.6 Sea state
The characteristics of the sea surface under the action of wind are called sea state. 26 Technical requirements
26.1 Quantities to be measured
The ten main quantities to be measured are wave height, period, wave direction, wave type and sea state; the auxiliary quantities to be measured are wind speed and wind direction. The observation of auxiliary quantities shall comply with the relevant provisions of GB12763.3
26.2 Accuracy of wave height, period and wave direction observation 26.2.1 The accuracy of effective height measured by instrument is ±10%, and the accuracy of effective period is ±0.5s. 26.2.2 The accuracy of effective wave height measured by instrument is ±15%, and the accuracy of effective wave period is ±0.5s: The accuracy of wave direction measured by compass azimuth (magnetic deviation correction must be performed when measuring wave direction by magnetic compass) is ±5°. 26.3 Observation time
For large-scale or cross-sectional stations, the ship shall observe once at the station; for continuous stations, the observation shall be traced back once every two hours, and the observation time is 02.05, 08, 11, 14, 17, 20, and 23 Beijing Standard Time. Daily measurements are only carried out during the day. 26.4 The length of time for recording the wave surface and the sampling time interval The wave surface recording instrument requires no less than 100 waves; the length of the recording time depends on the size of the effective wave period, generally 10 to 20 minutes, and the sampling time interval is 0.5s or 15.
26.5 Classification of wave types
According to the appearance characteristics of the waves, the wave types are divided into three categories: wind wave type, swell wave type and mixed wave type (see Table B1 in Appendix B). 26-6 Level of sea conditions
According to the shape of the wave crest, the degree of crest breakage and the number of waves, the sea conditions are divided into 10 levels (see Table B2 in Appendix B). 27 Current measurement methods
27.1 Observation of wave height and period
27.1.1 Measurement methods
27.1.1, 1 Shallow water wave measurement usually uses an easy-to-fix wave meter; deep water wave measurement generally uses a floating ball acceleration type wave meter. 27.1.1.2 The working mode of the ship (move or anchor) and the placement position of the probe shall be determined according to the wind and current. When the induction float is applied, the ship generally does not anchor, so that the float can be quickly separated from the hull. 27.1.1.3 The observation position should avoid obstacles that affect the waves, such as reefs, shoals, islands and artificial buildings. When there are obstacles near the measuring point, the conditions that affect the waves must be recorded. 27.1.1.4 When measuring waves in strong current areas, it is not advisable to use wave measurement that will cause errors such as drifting of wave records due to currents: when there is strong electrical interference near the measuring point, it is not advisable to use a remote wave meter.
27.1.2 Daily measurement method
27.1.2. When measuring the wave height and period daily, you should first look around the entire sea surface and pay attention to the distribution of wave height. Then measure the height and period of 10 significant waves (larger waves in the observed wave system) and take the average value, which is the effective slope height and its corresponding effective period. 27.1.2.2 When the wavelength is less than the length of the ship, the distance between the deck and the waterline can be used as a reference scale to measure the height and the distance between the two significant waves can be used as a reference scale to measure the effective slope height.2. Arrangement of salinity records of water samples measured by laboratory salinity meter When using laboratory salinity meter to measure the salinity of seawater samples, the salinity value 5 can be calculated by formula (8) based on the measured conductivity ratio R value and the temperature T value of the seawater sample; the measured conductivity ratio and the temperature of the seawater sample can also be used to look up the international oceanography common table to obtain S (uncorrected value) and S value, and then add the two to get the salinity value, S=S+AS. Part 5 Ocean Current Observation
21 Terminology
21.1 Current
The macroscopic flow of seawater is called ocean current, which is characterized by flow velocity and flow distance. 21.2 Flow velocity
The distance that seawater flows per unit time is called flow velocity. 21.3 Flow direction
The direction in which seawater flows is called flow distance. Due north is zero and measured clockwise. 22 Technical requirements
22.1 Quantities to be measured
The main quantities to be measured are velocity and direction; the auxiliary quantities to be measured are wind speed and direction. The measurement of auxiliary quantities shall comply with the relevant provisions of GB12763.3.
22.2 Accuracy of measurement
GB12763.2--91
22.2.1 The velocity and direction values of ocean current observations are specified as the average velocity and mainstream direction of 3 minutes. If the observed value of the velocity is not the average value of 3 minutes, the sampling period shall be stated in the observation record. 22.2.2 When the velocity is not greater than 100m/g, the accuracy of velocity measurement in sea areas with a water depth of less than 200m is ±5cm/s; in sea areas with a water depth of more than 200m, the accuracy of velocity measurement is ±3cm/s. The accuracy of current direction measurement is ±10°22.2.3 When the current velocity exceeds 100m/s, the accuracy of current velocity measurement is ±5% in the sea area with a water depth of less than 200m; the accuracy of current velocity measurement is ±3% in the sea area with a water depth of more than 200m. The accuracy of current direction measurement is ±10°. 22.3 Observation level
Refer to: Table 5 (see Article 14.3), select according to needs. However, the surface layer of ocean current observation is stipulated as the water layer within 3m. 22.4 Continuous observation time and frequency The length of continuous observation of ocean current should be no less than 25h, and the observation rate should be at least times per hour. The observation station for forecasting tidal currents should generally be no less than a week of continuous observation in accordance with good astronomical conditions. 23 Standard observation methods
23.1 When observing shallow ocean currents (water layer within three times the draft of the ship), small anchored buoys and small boats should be used for observation. 23.2 When using a survey vessel as a carrier to measure the currents in various layers below the shallow layer, if it is not a self-recording current meter, the observation can be carried out after the current meter is sunk to the predetermined observation water layer. + self-recording current meter, according to the load of the winch and wire rope, multiple current meters can be strung together to measure multiple layers of currents at the same time. The start time and end time of the observation must be recorded when measuring the current. 23.3 When using a self-recording current meter to observe the current with the help of a buoy or a submerged buoy, the vessel that launches and recovers the buoy (or submerged buoy) must have a special lifting device. After the buoy (or submerged buoy) is located, record the start time of the observation and the position of the buoy (or submerged buoy). After the observation, record the end time of the observation before recovering the buoy (or submerged buoy). Question: The flashing device on the buoy or submerged buoy must be truly watertight to ensure normal and continuous flashing. 23.4 When measuring currents in the deep sea, if it is difficult for the ship to drop anchor and the current velocity in the deep layer is indeed very small, the "dual machine method" can be used for observation, that is, on the source-moving ship, one current meter is placed in the predetermined observation water layer, and the other current meter is sunk in the "no current layer". The vector basis difference of the observation results of the two layers of current meters is the current observation value of the predetermined observation layer.
23.5 When the inclination angle of the wire rope or cable for placing the current meter exceeds 10°, the inclination angle should be corrected. The correction method is shown in Article 12.2.2. 23.6 When using a ship as a carrier for continuous current observation, the ship's position should be observed once an hour. If it is found that the ship is seriously wrong (exceeding the positioning accuracy requirement), it should be moved to the original position and the observation should be restarted. 23.7 Continuous observations around the mouth should generally not be missed. Anyone who interrupts the observation for more than two hours must repeat the observation. Start observation again. 24 Arrangement of observation records
24.1 When measuring current using a current meter with digital display, recording paper tape or direct reading, the measured data should be arranged according to the method and procedure required by the technical performance of the instrument to obtain the actual current velocity and true current direction. 24.2 When measuring current using an automatic current meter with tape recording, the recording tape can directly print out the current velocity and current direction values through a player and printer.
Chapter 6 Wave Observation
25 Terminology
25.1 Waves
Wind waves and swells appearing on the sea are collectively referred to as waves. Waves generated under the direct action of wind are called wind waves; waves from other sea areas, or waves left after the local wind force decreases sharply, the wind direction changes or the wind calms down, are all called swells. 25.2 Wave height
The vertical distance between adjacent wave crests and troughs is called wave height. In the continuous record of sea waves, the average of the individual wave heights of one third of the total number of wave heights is called the significant wave height.
25.3 Cycle
GE 12763.2—91
The time interval between two adjacent wave crests or two wave troughs passing through a fixed point is called a wave period. The average value of each wave period used to determine the significant wave height is called the significant wave period.
25.4 Interwave
The direction of the wave, with the north as zero and the direction measured clockwise. 25.5 Wave type
The appearance of the wave is called the wave type.
25.6 Sea state
The characteristics of the sea surface under the action of wind are called sea state. 26 Technical requirements
26.1 Quantities to be measured
The ten main quantities to be measured are wave height, period, wave direction, wave type and sea state; the auxiliary quantities to be measured are wind speed and wind direction. The observation of auxiliary quantities shall comply with the relevant provisions of GB12763.3
26.2 Accuracy of wave height, period and wave direction observation 26.2.1 The accuracy of effective height measured by instrument is ±10%, and the accuracy of effective period is ±0.5s. 26.2.2 The accuracy of effective wave height measured by instrument is ±15%, and the accuracy of effective wave period is ±0.5s: The accuracy of wave direction measured by compass azimuth (magnetic deviation correction must be performed when measuring wave direction by magnetic compass) is ±5°. 26.3 Observation time
For large-scale or cross-sectional stations, the ship shall observe once at the station; for continuous stations, the observation shall be traced back once every two hours, and the observation time is 02.05, 08, 11, 14, 17, 20, and 23 Beijing Standard Time. Daily measurements are only carried out during the day. 26.4 The length of time for recording the wave surface and the sampling time interval The wave surface recording instrument requires no less than 100 waves; the length of the recording time depends on the size of the effective wave period, generally 10 to 20 minutes, and the sampling time interval is 0.5s or 15.
26.5 Classification of wave types
According to the appearance characteristics of the waves, the wave types are divided into three categories: wind wave type, swell wave type and mixed wave type (see Table B1 in Appendix B). 26-6 Level of sea conditions
According to the shape of the wave crest, the degree of crest breakage and the number of waves, the sea conditions are divided into 10 levels (see Table B2 in Appendix B). 27 Current measurement methods
27.1 Observation of wave height and period
27.1.1 Measurement methods
27.1.1, 1 Shallow water wave measurement usually uses an easy-to-fix wave meter; deep water wave measurement generally uses a floating ball acceleration type wave meter. 27.1.1.2 The working mode of the ship (move or anchor) and the placement position of the probe shall be determined according to the wind and current. When the induction float is applied, the ship generally does not anchor, so that the float can be quickly separated from the hull. 27.1.1.3 The observation position should avoid obstacles that affect the waves, such as reefs, shoals, islands and artificial buildings. When there are obstacles near the measuring point, the conditions that affect the waves must be recorded. 27.1.1.4 When measuring waves in strong current areas, it is not advisable to use wave measurement that will cause errors such as drifting of wave records due to currents: when there is strong electrical interference near the measuring point, it is not advisable to use a remote wave meter.
27.1.2 Daily measurement method
27.1.2. When measuring the wave height and period daily, you should first look around the entire sea surface and pay attention to the distribution of wave height. Then measure the height and period of 10 significant waves (larger waves in the observed wave system) and take the average value, which is the effective slope height and its corresponding effective period. 27.1.2.2 When the wavelength is less than the length of the ship, the distance between the deck and the waterline can be used as a reference scale to measure the height and the distance between the two significant waves can be used as a reference scale to measure the effective slope height.1 Quantities to be measured
The main quantities to be measured are velocity and direction; the auxiliary quantities to be measured are wind speed and direction. The measurement of auxiliary quantities shall comply with the relevant provisions of GB12763.3.
22.2 Accuracy of measurement
GB12763.2--91
22.2.1 The velocity and direction values of ocean current observations are specified as the average velocity and mainstream direction of 3 minutes. If the observed value of the velocity is not the average value of 3 minutes, the sampling period shall be stated in the observation record. 22.2.2 When the velocity is not greater than 100m/g, the accuracy of velocity measurement in sea areas with a water depth of less than 200m is ±5cm/s; in sea areas with a water depth of more than 200m, the accuracy of velocity measurement is ±3cm/s. The accuracy of current direction measurement is ±10°22.2.3 When the current velocity exceeds 100m/s, the accuracy of current velocity measurement is ±5% in the sea area with a water depth of less than 200m; the accuracy of current velocity measurement is ±3% in the sea area with a water depth of more than 200m. The accuracy of current direction measurement is ±10°. 22.3 Observation level
Refer to: Table 5 (see Article 14.3), select according to needs. However, the surface layer of ocean current observation is stipulated as the water layer within 3m. 22.4 Continuous observation time and frequency The length of continuous observation of ocean current should be no less than 25h, and the observation rate should be at least times per hour. The observation station for forecasting tidal currents should generally be no less than a week of continuous observation in accordance with good astronomical conditions. 23
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