JP2972915B1 - Method and apparatus for measuring salinity and water temperature in brackish water area - Google Patents

Abstract

Abstract: PROBLEM TO BE SOLVED: To provide a method for measuring brackish water salinity and water temperature using a temperature measuring means and a salinity measuring means in a brackish water area by a relatively simple operation in a short time, and to provide a measuring device therefor. The brackish water is characterized by installing a cable connecting the temperature measuring means and the salinity measuring means in the brackish water area, inputting the measurement result to the calculation processing means via the cable, and measuring the salinity and the water temperature. In the brackish water area, a cable connecting the temperature measurement means and the salt content measurement means is installed, and the measurement result is connected to the calculation processing means via the cable to measure the temperature and the salt content from the measurement result. By defining a relational expression between water temperature and salinity and using this relational expression, the salinity is calculated without actually measuring the salinity based on the actual measured value of the water temperature, and the salinity and the water temperature of the brackish water are measured. Apparatus method and for its measure the salt and water brackish water to be.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for measuring salinity and water temperature in a brackish water area and an apparatus therefor.

[0002]

2. Description of the Related Art At the mouth of an inner bay, there is a brackish area where seawater and river water are mixed, and a brackish lake is partially closed. The brackish lake has a nearly two-layer structure due to the difference in density between seawater flowing from the open sea and freshwater supplied from rivers. Then, a salt jump layer is formed in a portion where the salt content changes suddenly. It is important to know the distribution and dynamics of the salinity layer and the lower saline layer in order to secure fishery resources and protect the environment. When the saltwater flows create a good lake bottom environment, while oxygen-depleted anoxic water masses enter the fishing grounds,
Damage such as death of fish and shellfish occurs. Also, near the mouth of a river, there is a phenomenon that seawater enters the river from the river because the riverbed is below the sea surface. Seawater crawls up the riverbed, and river water flows over it, flowing from the estuary to the sea. The seawater layer is called a saltwater wedge because of its shape. Understanding the distribution of the salinity layer is also important from the viewpoint of environmental protection and salt damage prevention. When considering environmental issues from a global perspective, the effect of sea level rise due to global warming is the first place where brackish waters emerge, so brackish waters are a suitable place for monitoring posts for global environmental research. In such brackish waters, various devices have been developed to measure the aquatic environment. (1) Digital underwater sounding probe (Seiwa Nishimura et al., Brackish Water Research 1, 1-9) to understand the existence and distribution of salt crests and salt water wedges. (2) A continuous dynamic impedance of acoustic transducer installed at the bottom of the lake receives reflections reflected at the boundary between the two layers, and grasps the dynamics of the time series of the saline layer, (3) An observation system for measuring a moving direction and a moving speed of a thermocline in a brackish water area by a change in a distribution water temperature observed by an optical fiber distribution type thermometer (Japanese Patent Application Laid-Open No. 9-210741). In these observations using sound and temperature, the relationship between salinity and salinity is calculated from indirect information that correlates with salinity, and the vertical distribution is measured, or continuous measurement of salinity is performed using a memory-type salinity / thermometer. Or However, in brackish waters where there is a wide range of salinity from freshwater to seawater, salinity measurement is fundamental, and the development of a measurement system using a simple salinity measuring device is desired.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for measuring the salt content and water temperature of brackish water using a temperature measuring means and a salinity measuring means in a brackish water area by a relatively simple operation in a short time. It is to provide a measuring device for that.
Further, an object of the present invention relates to measurement of salinity in a brackish water area, and relates to a method for measuring brackish water's salinity and water temperature, which can calculate the salinity from the measured water temperature using a relational expression of the water temperature and the salinity, and a measuring device therefor. To provide.

[0004]

The inventor of the present invention can measure the salinity and temperature of salt water by using a multipoint salinity / temperature sensor in which a plurality of salinity / temperature sensors are connected to a cable. At that time, it is possible to measure the change of salinity and temperature in the horizontal direction by installing multiple salt and temperature sensors connected to the cable on the lake bottom or riverbed in the brackish water area, or by installing it vertically in the water We found that we could observe vertical salinity and temperature changes. In addition, as a result of continuing these measurements and organizing the measurement results, it was newly found that the correlation between water temperature and salinity in brackish water was extremely high. The present inventors have found that it is possible to calculate the salinity by measuring the water temperature by using the relational expression between the salinity and the temperature of the resulting brine, thereby completing the present invention.

[0005] That is, according to the present invention, the brackish, warm
Probe consisting of a salinity measuring means and a salinity measuring means.
A method of measuring the salinity and water temperature of a brackish water characterized by installing several connected cables, inputting the measurement results to the calculation processing means via the cable, and measuring the salinity and water temperature. By installing a cable connecting the means and the salinity measuring means, connecting the measurement result to the calculation processing means via the cable, determining the relational expression of water temperature and salinity from the measurement result of temperature and salinity, and using this relational expression Based on the actual measured value of the water temperature, calculate the salinity without actually measuring the salinity, a method for measuring the salinity and moisture of brackish water, which comprises measuring the salinity and the water temperature of brackish water, by the method described above. A method for measuring the salinity and moisture of brackish water, which measures the measured temperature of the brackish water using an optical fiber distribution type thermometer when measuring the salinity and water temperature of brackish water, temperature measurement installed in brackish water areas means and salinity measurement means, It consists degree measuring means and salinity measuring means
A measuring device for measuring salt and water temperature of brackish water, comprising: a cable to which a plurality of probes to be connected are connected, calculation processing means for inputting measurement results via the cable, and temperature measuring means installed in the brackish water area. Salinity measuring means, cable to which temperature measuring means and salinity measuring means are connected, calculation processing means for inputting each measurement result via the cable, means for determining the relational expression of water temperature and salt water from temperature and salinity measurement results, measurement In the brackish water salinity and water temperature measuring device, comprising the brackish water salinity and water temperature measuring device, comprising: Having a cable connected to an optical fiber distribution type thermometer for measuring water temperature, in addition to the cable to which the temperature measuring means and the salt measuring means and the cable to which the temperature measuring means and the salt measuring means are connected; Brackish water salinity and temperature of the measuring device is provided, wherein.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Salt water and fresh water constituting a brackish water area are:
Due to the different densities, salt water having a high density has a two-layer structure including a lower layer and fresh water having a low density has an upper layer. These two layers differ in salinity and water temperature. In the lower saline layer, the water temperature remains constant throughout the year and remains almost constant. On the other hand, the temperature of the upper freshwater layer is low in winter and high in summer. In rivers where salt water and fresh water come into contact, the shore of a brackish lake that comes and goes, and a boundary between two layers (fresh salt boundary), there is a salinity crest where the salinity changes suddenly at the part where both bodies of water come into contact. Then, the salinity of the salinity layer near the boundary indicates an intermediate value between the salinity of both water bodies. At the boundary between the freshwater layer and the saltwater layer, there is a thermocline where the water temperature changes rapidly, and the temperature between the two layers is intermediate (Figs. 1 and 2).
Also, the salt content of the salt water layer naturally has a higher value than that of the fresh water layer. By measuring and analyzing the water temperature and salinity of the brackish water area, the existence and flow state of the salt water can be clarified.

[0007] When measuring the temperature and salinity in the vicinity of each of these layers and their boundaries, measurement is performed by means of temperature detection and salinity detection means at the site to be measured. And
For this purpose, a thermistor sensor is used as the temperature measuring means, and a sensor consisting of an electromagnetic induction cell for measuring electric conductivity is used as the salt content measuring means. Attach and measure. The measurement result is input to the computing device via a cable in order to perform the counting process on the measurement result. as a result,
At the same time, it became possible to measure the salinity and water temperature for the same place and perform the tally processing. This device has a relatively simple overall structure, is easy to handle, and can provide sufficiently accurate results. At the same time, by installing a cable with a large number of thermistor sensors on the lake bottom or riverbed in a brackish water area, it is possible to observe changes in salinity and temperature in the horizontal direction. Also, by installing the cable in the vertical direction in the water, it is possible to observe changes in the salt content and the water temperature in the vertical direction (FIG. 4). The measured electrical conductivity and water temperature data output from the sensor can be sent directly to the cable via the data input / output terminal. The power can be supplied from the outside, or can be attached to individual devices by means such as an internal battery. A plurality of sensors can be attached to the cable (CT1, 2,.
3, 4, and 5). For measurement, data can be collected by sequentially switching the sensors. For the collected data, the measurement results are displayed by a salinity / thermometer, and the measurement results are further input to a data recording device and recorded (FIG. 5).

When measuring the water temperature distribution over a wide range, it is effective to use an optical fiber. The system for measuring the temperature distribution using an optical fiber is based on the method shown in FIG. This measuring method uses the following principle. When a laser pulse is incident on an optical fiber cable, Rayleigh scattered light due to fluctuations in the refractive index of glass molecules and Raman scattered light due to movement of molecules are generated. Among them, the intensity of the Raman scattered light on the anti-Stokes side largely depends on the temperature of the optical fiber as compared with that on the Stokes side. Therefore, the temperature at the position where the scattered light occurs can be obtained from the ratio of the backscattered light (light returning to the incident end), and the position can be obtained from the delay time until the backscattered light returns. it can. In this measurement method, the entire area of one long optical fiber cable can be used as a thermometer by utilizing the temperature dependence of the back scattered light (Raman scattered light), which is effective for measuring a wide continuous temperature distribution. is there. The distance resolution is 1 m. For example, in an optical fiber of 2000 m,
It is possible to obtain 2000 points of water temperature data. The main part of the measurement system is an optical system (including a laser light source for generating laser pulses, an optical fiber switch for sequentially switching a plurality of optical fibers at high speed, and a detector for converting a received optical signal into an electric signal). And a data processing unit (consisting of an A / D converter, an averaging unit, a board computer, etc., which performs temperature data calculation processing and high-speed data output to the outside). The system further includes a data display / recording device and an optical fiber for temperature measurement in addition to the measurement system. The data display / recording device includes a system control function for controlling the operation of the entire system, a distribution temperature recording function having a storage device, and a CR.
This is a computer having a function of displaying a distribution temperature by a T monitor (FIGS. 6 to 9). When an optical fiber cable is used, the water temperature can be measured at many points, and this is an effective means when trying to measure at many points.

[0009] The salt content can be measured by using a salt meter. This is known to use electrical conductivity. As described above, it is desirable to measure the salinity concentration by installing it at a specific point by using this. However, it is expensive, expensive to maintain, and economically difficult and impractical to install repeatedly at many points. From this,
In the measurement of salinity, it is not effective to install a large number of sensors and measure them when necessary, and to calculate the salinity from the actually measured water temperature of the present invention is a practically effective means.

The present inventor has newly found that a significant correlation exists between the salt content and the water temperature when the salt content and the water temperature are measured simultaneously. Hereinafter, the contents of the observation will be described. Fig. 3 shows a multipoint CT on the riverbed approximately 5.5km upstream from the estuary in the river of western Eshima, Shimane Prefecture.
(Electric conductivity and temperature) The places where the sensors are installed are shown (CT1, CT2, CT3, CT4, CT5). FIG. 10 shows the measured values of salinity and water temperature at these points every 10 minutes. In this figure, the upper part shows the salt content and the lower part shows the water temperature. From these figures, it can be read that, at the date and time when the water temperature of the riverbed is rising, the salinity is also rising accordingly. As an example, for the CT1, a specific period (27 days to 30 days)
FIG. 11 is an enlarged view of the state of (day). From this figure, the above relationship between the water temperature of the brine layer and the salinity becomes clearer. For example, looking at the measurement result of the result CT1 on the 27th, it is understood that the relationship between the water temperature and the salinity can be displayed by a linear function. If it can be represented by a linear function, it will be noted that the subsequent numerical processing is simple and easy to calculate, and if the relationship between salinity and water temperature is obtained by the least square method, it can be approximated by a specific linear equation ( (FIG. 12). When this relational expression is obtained, it is as follows. Y = −33.352 + 4.0159X In the formula, Y represents a salt, and X represents a water temperature. As is clear from this figure, the relationship between the salt content and the water temperature shows little variation and shows good agreement. On the other hand, when this relational expression is given, regarding salinity and water temperature, for example, if the result of measuring the water temperature is obtained, using this relation, the salinity can be obtained from the measured temperature. . Needless to say, when the salt concentration is clarified by the measurement, the water temperature can be determined on the contrary.

Next, using the obtained relation of the specific linear equation, an attempt was made to compare the case where the salt concentration was calculated from the water temperature with the calculated value and the case where the salt concentration was calculated with the actually measured value. In this case, the results obtained by deriving the results on the 27th and 28th using the data on the 27th are shown (FIGS. 13 to 18). This means that if there is no change in natural conditions such as large weather if there is a difference of about one day, there is no change in the brackish water area, and as a result, the relationship between the water temperature and the salinity measured on the 27th is unchanged. It is to confirm that it can be used. FIG. 11 is a diagram showing the results of the previous value of T1 from 0:00 on the 27th to 0:00 on the 28th. FIG. 12 shows the results of T1 from 00:00 on the 28th to 0:00 on the 29th. The results of estimating the salt concentration based on the water temperature are as shown by the dotted lines in these figures, and it can be seen that the estimated values are in good agreement with the actually measured values shown in practice. In this way, a relational expression is derived using the actually measured water temperature and salinity once measured,
Next, it can be confirmed that the value obtained by calculating the corresponding salinity from the actually measured value of the water temperature matches well with the actually measured value.

Next, a method of using the measurement result of the water temperature by the optical fiber distribution type thermometer will be described. Install fiber optic cables along the riverbed from the observation station to the point to be measured. This point is a place close to the place where the cable where the means for measuring water temperature and salinity is installed is installed. A method of forming a loop type by folding back the end of the cable can be adopted. When installed up to 700 m from the shore, the total length of the cable is 1400
m. In the temperature measurement, the temperature can be measured every 1 m, and the measurement time is set (for example, about 9 minutes). The setting of the measurement time can be determined as appropriate. The relationship between the water temperature and the salinity at the measurement point is determined by the water temperature and salinity measurement means installed near the measurement point. For this measurement, a measurement device in which a temperature measurement sensor composed of the above-described thermistor and salt measurement by electric conductivity measurement are combined and installed in a probe and connected to a cable is used. Using this measuring device, water temperature and salinity are actually measured, and using the results, a relational expression (primary equation) of water temperature and salinity at one point is determined by means similar to the above (in this measurement, Since the measurement was performed at the same point and at the same time, the above-mentioned relational expression can be used.) Next, from the actually measured value of the water temperature distribution measured using the optical fiber cable, the salt concentration distribution was calculated using the above-mentioned relational expression. Can be calculated. When showing the result of calculating the salinity based on the measured value of the water temperature,
This is as shown in FIGS. The horizontal axis indicates the distance from the shore, and the vertical axis indicates the water temperature (actually measured value) and the salinity (calculated value). According to this method, since the water temperature can be measured in a wide range and at multiple points (water temperature distribution), it can be seen that the corresponding wide range and multiple points (salinity distribution) can be calculated. As a result, when examining the dynamics of brackish waters, it will be possible to clarify the conditions at many points. In this figure, from December 27, 2
It shows the results for a specific time period up to 9 days.

From these results, it can be seen that the salt content can be calculated by the following method. Measure the water temperature and salinity of the measurement point at a specific date and time. For the actual measurement, a device capable of measuring water temperature and salinity is used. Any device can be appropriately used as long as it can measure the water temperature and the salt content. Specifically, the water temperature can be measured by a thermistor, and the salt content can be measured by a device for measuring electric conductivity. These instruments can be connected to a cable and measured at the required time. A relational expression of water temperature and salinity is obtained based on the measured values. Since it is complicated to directly measure the two values of the water temperature and the salt content, it is possible to measure only the water temperature and calculate the salt content using the measured value and the relational expression. An optical fiber temperature sensor or the like can be used for measuring the water temperature in addition to the thermistor. Then, this relational expression can calculate the salinity from the data of only the water temperature as long as the condition is kept constant even if the time elapses. From the results shown in the figure, it can be seen that the estimated salt content has an error of several percent to several tens percent, and can be used sufficiently for practical use.

Using the relationship between the water temperature of the brackish water area and the salt concentration,
The method of calculating the salt concentration in the brackish water area is as follows. (1) To set the brackish water area to be measured and install water temperature measurement means to measure the water temperature. (A) As means for actually measuring the water temperature, a thermistor sensor is installed at a specific place, and these are connected to collect each temperature, and the result can be input to a recording device. Similarly, the salt concentration can be input to the recording device. A CT sensor having both of them can be used. (B) In addition, an optical fiber distribution type sensor cable is laid on the bottom of the water. A required number of thermistor sensors and salt sensors are attached along the sensor cable so that the measurement results of the water temperature and the salt can be input. (2) Water temperature and salinity are actually measured, and a relational expression of water temperature and salinity is obtained based on the actually measured values. It is preferable that the relationship between the water temperature and the salinity be a linear expression if a simple relational expression is used, since the handling is easy in later calculations and the like. It is necessary to define a new relational equation as the situation in the brackish water area changes. As long as no significant change occurs in the brackish water area, the relational expression once determined can be used. When it is clear that the relationship changes with the passage of time, it is necessary to continuously measure the relationship between the water temperature and the salt concentration and update the relational expression sequentially. (3) Using the relational expression obtained in the above (2), the salinity concentration is calculated from the actually measured water temperature after a lapse of a specific time. Further, the state of brackish water, the flow state of the salt water layer, and the like can be clarified from the actually measured water temperature of the salt water layer and the calculated salt water concentration.

[0015]

Next, the contents of the present invention will be described with reference to specific examples in accordance with the above-mentioned procedure. The present invention is not limited to this embodiment. Example 1 (1) Installation of sensor The downstream of the Eno River was set as the brackish water area to be measured. Next, a 700 m long cable having a multi-point CT sensor (electrical conductivity / temperature sensor) was placed near the riverbed (1
5 cm above) (FIGS. 3 and 4). In this embodiment, the number of the multipoint type CT sensors is five (CT1 to CT5). The characteristics of the sensor were as follows. The water temperature measurement sensor is a thermistor, the measurement range is -2 to 35 ° C, and the accuracy is ± 0.
02 ° C. The electric conductivity measurement sensor was an electromagnetic induction cell, the electric conductivity measurement range was 0 to 70 mS / cm, and the electric conductivity measurement accuracy was ± 0.03 mS / cm. The sensor interval was 50 m, and the total cable length was 500 m.
The measurement / processing time per channel was 49 seconds, and the measurement interval was 5 minutes such as 5 minutes, 10 minutes, and 15 minutes. Each C
FIG. 5 shows a state in which the switching device for measurement of the T sensor and the recording device are connected. (2) Investigation of brackish water dynamics Using the above sensors, water temperature and salinity were measured, and the output results were recorded (FIGS. 10 and 11). In this way, the dynamics of the brackish water area could be clarified by measuring the water temperature and salinity. (3) Calculation of salinity using the relationship between water temperature and salinity Regarding the measurement result of CT1, data on December 27 was taken out and arranged, thereby obtaining a relational expression of the following linear function (FIG. 12). This relational expression is as follows. Y = −33.352 + 4.0159X In the formula, Y represents a salt, and X represents a water temperature. As is clear from this figure, the relationship between the salt water and the water temperature has little variation and is in a specific relationship. Using this relational expression,
With respect to the water temperature, for example, if a result of measuring the water temperature can be obtained, using this relationship, the salinity can be determined from the measured temperature. CT1, CT3,
From the water temperature data on December 27 and 28 of CT5,
Each salt content was calculated using the above relational expression. The result is shown in FIG.
3 to 18 are as indicated by dotted lines. The measured value of salinity is shown by a solid line. From these results, it was confirmed that the result of calculating the measured value of the salt concentration from the measured value of the water temperature using the relational expression of the linear function was consistent with the actually measured value. Moreover, as a result of organizing using the actual measurement data of CT1, C
It was confirmed that the method was also effective for calculating data of CT3 to CT5 100 m or more away from T1.

Example 2 A brackish water area to be measured was set near the place of Example 1.
Next, an optical fiber distribution type thermometer was installed, and its output was connected to a calculator (FIGS. 3 and 6). The measuring method is a loop method, the used optical fiber cable is 2 km in total length, 3 mm in outer diameter PVC coated cord, distance resolution 1 m, maximum measuring distance 8 km / loop, measuring temperature range -200 to 500 ° C,
Maximum number of channels is 4 and power consumption is about 200
W, power supply was AC100V 50 / 60Hz. Using the relational expression between the water temperature of the salt water layer and the salt content obtained in Example 1, the salt content was calculated from the water temperature value obtained by the optical fiber distribution type thermometer. The results are as shown in FIGS.

Example 3 A brackish water area to be measured is set, and the points shown in FIG.
Five multi-point CT (electric conductivity / temperature) sensors were installed (CT 1 to 5). Regarding the point of CT2, the measurement results of the water temperature and the salinity are as shown in FIG. The relationship between water temperature and salinity was calculated by sorting the data of February 3 in the data of the measurement results, and a linear equation was obtained (FIG. 26). Using this linear relationship, the salinity was calculated from the measured water temperature (FIG. 27).
~ 29). The results are shown by dotted lines. And it was confirmed that the result calculated by comparing with the measured value shown by the solid line was consistent. Similarly, the same operation was performed for the point of CT4, and it was confirmed that the measured value and the calculated value of the salinity coincided with each other (FIGS. 27 to 29).

[0018]

According to the method and apparatus of the present invention, the water temperature and salinity of a brackish water area can be measured by a relatively simple operation in a short time. According to the present invention, when calculating the salt content of brackish water,
It can be calculated from the water temperature based on a previously measured relational expression between the water temperature and the salt content. Therefore, when measuring,
It is not necessary to measure the water temperature and salinity every time, and once the relationship between the water temperature and the salinity is determined, it is possible to calculate the salinity from the actual measured value of the water temperature as long as the state is considered to be maintained. This eliminates the need to repeat complicated operations. In addition, by regularly correcting the relationship between water temperature and salinity, if data is continuously accumulated over a long period of time, regularity and the like can be grasped, and this can be used for utilization in marine resources and environmental conservation.

[Brief description of the drawings]

FIG. 1 is a diagram showing a brackish water area in a river.

FIG. 2 is a diagram showing a brackish water area in a lake.

FIG. 3 is a diagram showing installation locations of a multipoint CT sensor and an optical fiber distribution type thermometer.

FIG. 4 is a diagram showing a method of installing a multipoint CT sensor and an optical fiber distribution type thermometer.

FIG. 5 is a diagram showing the connection between the switching unit of the multipoint CT sensor and the recording device.

FIG. 6 is a diagram showing a method of installing an optical fiber distribution type thermometer.

FIG. 7 is a diagram showing the connection between the switching means of the optical fiber distribution type thermometer and the recording device.

FIG. 8 is a diagram showing connection of an optical fiber distribution type thermometer.

FIG. 9 is a diagram illustrating the principle of an optical fiber distribution type thermometer.

FIG. 10 is a diagram showing measurement results of a multipoint CT sensor.

FIG. 11 is a diagram showing measurement results of a multipoint CT sensor.

FIG. 12 is a diagram showing the relationship between the salt water content and the salt water temperature obtained from the measurement results of the multipoint CT sensor.

FIG. 13 is a diagram showing a result of calculating salinity from a measurement result of the multipoint CT sensor and a measured water temperature value using a relationship between the water temperature and the salinity.

FIG. 14 is a diagram showing a result of calculating salinity from a measurement result of a multipoint CT sensor and a measured water temperature value using a relationship between water temperature and salinity.

FIG. 15 is a diagram showing a result of calculating salinity from a measurement result of a multipoint CT sensor and a measured water temperature value using a relationship between water temperature and salinity.

FIG. 16 is a diagram showing a result of calculating salinity from a measurement result of a multipoint CT sensor and a measured water temperature value using a relationship between water temperature and salinity.

FIG. 17 is a diagram showing a result of calculating salinity from a measurement result of a multipoint CT sensor and a measured water temperature value using a relationship between water temperature and salinity.

FIG. 18 is a diagram showing a result of calculating salinity from a measurement result of a multipoint CT sensor and a measured water temperature value using a relationship between water temperature and salinity.

FIG. 19 is a diagram showing a measurement result of an optical fiber distribution type thermometer and a calculation result of salt content.

FIG. 20 is a diagram showing a measurement result of an optical fiber distribution type thermometer and a calculation result of salt content.

FIG. 21 is a diagram showing a measurement result of an optical fiber distribution type thermometer and a calculation result of salt content.

FIG. 22 is a diagram showing a measurement result of an optical fiber distribution type thermometer and a result of calculating salt content.

FIG. 23 is a diagram showing a measurement result of an optical fiber distribution type thermometer and a calculation result of salt content.

FIG. 24 is a diagram showing a measurement result of an optical fiber distribution type thermometer and a calculation result of salt content.

FIG. 25 is a diagram showing a measurement result by a multipoint CT sensor.

FIG. 26 is a diagram showing a relationship between water temperature and salinity obtained from measurement results obtained by a multipoint CT sensor.

FIG. 27 is a diagram showing measurement results obtained by a multipoint CT sensor and salinity calculated from the water temperature using a relational expression of water temperature and salinity.

FIG. 28 is a diagram illustrating measurement results obtained by a multipoint CT sensor and salinity calculated from the water temperature using a relational expression of water temperature and salinity.

FIG. 29 is a diagram showing measurement results obtained by a multipoint CT sensor and salinity calculated from the water temperature using a relational expression of water temperature and salinity.

FIG. 30 is a diagram showing installation locations of a multipoint CT sensor and an optical fiber distribution type thermometer.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-58113 (JP, A) JP-A-9-210741 (JP, A) JP-A-5-133818 (JP, A) 105871 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01K 1/02 G01D 21/00 G01N 27/74

Claims (6)

(57) [Claims] 1. A temperature measuring means and a salt measuring means in a brackish water area.
A method for measuring the salt content and the water temperature of brackish water, comprising installing a cable connected to a plurality of probes composed of the above, and inputting the measurement result to the calculation processing means via the cable, and measuring the salt content and the water temperature. 2. A cable connecting the temperature measuring means and the salt content measuring means is installed in the brackish water area, and the measurement result is connected to the calculation processing means via the cable to calculate the water temperature and the salt concentration from the measurement result of the temperature and the salt content. By defining a relational expression and using this relational expression, the brackish water is characterized by calculating the salt concentration without actually measuring the salinity concentration based on the actually measured water temperature, and measuring the salt content and the water temperature of the brackish water. To measure the salinity and water temperature of the sea. 3. The brackish water salinity and water temperature according to claim 2, wherein when measuring the brackish water salinity and the water temperature, the measured value of the water temperature is measured using an optical fiber distribution type thermometer. Method. 4. Installation temperature measuring means and salinity measuring means brackish, and a temperature measuring means and salinity measuring means
An apparatus for measuring salt and water temperature of brackish water, comprising a cable to which a plurality of probes are connected, and calculation processing means for inputting measurement results via the cable. 5. A temperature measuring means and a salt measuring means installed in a brackish water area, a cable connecting the temperature measuring means and the salt measuring means, a calculation processing means for inputting each measurement result via the cable, a temperature and a salinity A means for determining a relational expression of water temperature and salinity from measurement results, and a means for calculating salinity based on a measured value of the measured water temperature. 6. A measuring device for measuring salt content and water temperature of brackish water,
Having a cable connected to an optical fiber distribution type thermometer for measuring water temperature, in addition to the temperature measuring means and the salt measuring means installed in the brackish water area and the cable to which the temperature measuring means and the salt measuring means are connected. The measuring device for salt and water temperature of brackish water according to claim 5, characterized in that: