Comprehensive treatment method and device for deep extraction of ocean mixed layer

Abstract

The invention provides a comprehensive processing method and device for ocean mixed layer depth extraction, and the method comprises the steps: collecting ocean temperature profile data in a global range, and carrying out the quality control of the ocean temperature profile data; performing interpolation on the ocean temperature profile after quality control, and determining that an interpolation result reaches the depth with the resolution being a first set value; calculating a first mixed layer depth of the to-be-detected ocean, and obtaining a second mixed layer depth through the temperature standard deviation of different depths in the profile of the to-be-detected ocean; comparing the two possible mixing layer depths, and when the first mixing layer depth is greater than the second mixing layer depth, selecting the first mixing layer depth as the final mixing layer depth; otherwise, taking the second mixing layer depth as the final mixing layer depth. According to the technical scheme, the limitation of an existing mixed layer depth calculation method can be overcome, the situation that a temperature gradient threshold value is subjectively set and is not suitable for a complex ocean profile is avoided, and the objectivity of calculating the spring layer thickness is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of ocean mixed layer depth calculation, and in particular relates to a comprehensive processing method and device for extracting ocean mixed layer depth. Background Art

[0002] The upper mixed layer of the ocean is a layer of water located on the surface of the ocean with approximately uniform distribution of physical properties such as temperature, salinity and density. It has the sea surface as the upper boundary and the top of the thermocline as the lower boundary. It plays an important role in the ocean system and affects the physical, chemical and biological processes of the ocean. The depth of the mixed layer refers to the thickness of the upper mixed layer of the ocean, which is usually between tens of meters and hundreds of meters. Changes in the depth of the mixed layer are related to external factors such as wind stress, atmospheric ocean heat flux, and freshwater flux. They bring energy and matter from the surface into deeper water layers by affecting the mixing process, resulting in changes in the uniformity of the water body in the mixed layer, the gradient of temperature and salinity, and the change in the depth of the mixed layer.

[0003] At present, the depth of the mixed layer is often calculated using the vertical temperature profile data of seawater. The calculation methods of the mixed layer depth mainly include: threshold method: 0.2℃ or 0.03kg / m 3 As a threshold, the change of temperature or density in the control value mixed layer is within the threshold. Gradient method: 0.05℃ / m or 0.01kg / m 4 As the gradient critical value, the depth of the mixed layer is found through the gradient critical value to ensure that the gradient in the mixed layer is less than the critical value. Hybrid algorithm: By combining methods such as the threshold method and the gradient method, a variety of possible mixed layer depths are calculated, and then according to the different seasons in which the profile is located, a complex process is selected to select the most appropriate depth as the mixed layer depth. The above methods often rely on subjective threshold setting and are difficult to apply to different ocean vertical profiles. Objective and applicable mixed layer depth calculation methods for various profile situations need to be further developed.

[0004] Therefore, how to provide a comprehensive processing method and device for extracting the depth of the ocean mixed layer that can overcome the limitations of the existing mixed layer depth calculation method, avoid the situation where the subjective setting of the temperature gradient threshold is not suitable for complex ocean profiles, and increase the objectivity of calculating the thickness of the jump layer has become a technical problem that needs to be solved urgently. Summary of the invention

[0005] The embodiment of the present invention provides a comprehensive processing method and device for extracting the depth of the ocean mixed layer, which can overcome the limitations of the existing mixed layer depth calculation method, avoid the situation where the subjective setting of the temperature gradient threshold is not suitable for complex ocean profiles, and increase the objectivity of calculating the jump layer thickness.

[0006] In one embodiment of the present invention, a comprehensive processing method for extracting the depth of an ocean mixed layer is provided, comprising:

[0007] S101. Collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data;

[0008] S102, interpolating the ocean temperature profile after quality control to determine the depth at which the interpolation result reaches a resolution of a first set value;

[0009] S103, using a straight line approximation algorithm to calculate the first mixed layer depth D1 of the ocean to be detected;

[0010] S104. Calculate the characteristic parameters of the ocean profile to be detected by using the temperature standard deviation γ(n) at different depths. Obtaining a second mixed layer depth D2;

[0011] S105. Compare two possible mixing layer depths. When the first mixing layer depth D1 is greater than the second mixing layer depth D2, select the first mixing layer depth D1 as the final mixing layer depth. When the second mixing layer depth D2 is greater than or equal to the first mixing layer depth D1, take the second mixing layer depth D2 as the final mixing layer depth.

[0012] Further, the ocean temperature profile after quality control is interpolated to determine the depth at which the interpolation result reaches a resolution of a first set value, including:

[0013] Using the cubic spline interpolation method, all profiles after quality control are interpolated to above 0 m, 1 m, 2 m, 3 m, ..., 1000 m, so that their vertical resolution reaches the first set value;

[0014] During the interpolation process, since the first point of the ocean temperature profile is on the sea surface of the ocean to be measured, the first data point on each ocean temperature profile is set as the sea surface data for interpolation.

[0015] Furthermore, a straight-line approximation algorithm is used to calculate the first mixed layer depth D1 of the ocean to be detected, including:

[0016] Assume that the seawater temperature distribution is T i , i represents depth; when i = 0, it represents sea surface temperature. Linear fitting is performed on the temperature profile, and the temperature corresponding to the depth of the data is obtained as And calculate the characteristic parameter δ(n):

[0017]

[0018] Where n represents the depth, when n = 0, it represents the sea surface temperature, T i is the temperature of the temperature profile at depth i, is the temperature at depth i of the fitting line;

[0019] Take the constant m=5 and calculate the characteristic parameter σ(n) of m data points below the fitting depth

[0020]

[0021] Where T is the temperature profile, is the temperature of the fitted straight line;

[0022] Calculate the ratio λ(n) of the characteristic parameter σ(n) to the characteristic parameter δ(n):

[0023]

[0024] When the ratio of the characteristic parameter δ(n) to the characteristic parameter σ(n) is the largest, the depth of the ocean to be detected is taken as the mixed layer depth D1.

[0025] Furthermore, the characteristic parameters are calculated by the temperature standard deviation γ(n) at different depths in the ocean profile to be detected. Obtaining the second mixed layer depth D2 includes:

[0026] Calculate the temperature standard deviation γ(n) at each depth of the ocean to be detected:

[0027]

[0028] Where n is the current depth, is the average seawater temperature above a depth of n meters;

[0029] Calculate feature parameters

[0030]

[0031] Among them, γ(n) is the standard deviation of temperature at a depth of n meters; γ(1.3×n) is 1.3 times the standard deviation of temperature at a depth of n meters; when the characteristic parameter When it is at its maximum, this depth is taken as the mixed layer depth D2.

[0032] Furthermore, collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data include:

[0033] Remove the ocean temperature profiles whose depth profiles cannot always increase and the ocean temperature profiles with more than 2 consecutive missing values;

[0034] The number of data points on the entire section line of the ocean temperature profile is greater than 50, and there are more than 2 data points between 10 meters and 40 meters.

[0035] Furthermore, collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data include:

[0036] Each ocean temperature profile has a sufficiently wide coverage area, with the minimum depth below 10 meters and the maximum depth above 1000 meters.

[0037] The ocean temperature is required to be between -2°C and 35°C, and the maximum temperature difference in the entire profile is greater than 1°C;

[0038] Among them, the maximum temperature difference between 0 and 20 meters is greater than the maximum temperature difference below 20 meters.

[0039] Furthermore, the first set value is 1 meter.

[0040] In another embodiment of the present invention, a comprehensive processing device for extracting the depth of an ocean mixed layer is provided, based on a comprehensive processing method for extracting the depth of an ocean mixed layer as described in any one of the above items, characterized in that the device comprises: a data collection module, an interpolation module, a first mixed layer depth module, a second mixed layer depth module and a processing module;

[0041] The data collection module is used to collect ocean temperature profile data worldwide and perform quality control on the ocean temperature profile data;

[0042] The interpolation module is used to interpolate the ocean temperature profile after quality control and determine the depth at which the interpolation result reaches a resolution of a first set value;

[0043] The first mixed layer depth module is used to calculate the first mixed layer depth D1 of the ocean to be detected using a straight line approximation algorithm;

[0044] The second mixed layer depth module is used to calculate its characteristic parameters through the temperature standard deviation γ(n) at different depths in the ocean profile to be detected. Obtaining a second mixed layer depth D2;

[0045] The processing module is used to compare two possible mixing layer depths. When the first mixing layer depth D1 is greater than the second mixing layer depth D2, the first mixing layer depth D1 is selected as the final mixing layer depth. When the second mixing layer depth D2 is greater than or equal to the first mixing layer depth D1, the second mixing layer depth D2 is taken as the final mixing layer depth.

[0046] The beneficial effects brought by the present invention are as follows:

[0047] It can be seen from the above scheme that the embodiment of the present invention provides a comprehensive processing method and device for extracting the depth of the ocean mixed layer, by collecting ocean temperature profile data on a global scale and performing quality control on the ocean temperature profile data; interpolating the ocean temperature profile after quality control to determine the depth at which the interpolation result reaches a resolution of the first set value; using a linear approximation algorithm to calculate the first mixed layer depth of the ocean to be detected; calculating its characteristic parameters through the temperature standard deviation at different depths in the ocean profile to be detected, and obtaining the second mixed layer depth; comparing two possible mixed layer depths, when the first mixed layer depth is greater than the second mixed layer depth, selecting the first mixed layer depth D1 as the final mixed layer depth, and when the second mixed layer depth is greater than or equal to the first mixed layer depth, taking the second mixed layer depth as the final mixed layer depth. The technical scheme of the present invention can overcome the limitations of the existing mixed layer depth calculation method, avoid the situation where the subjective setting of the temperature gradient threshold is not suitable for complex ocean profiles, and increase the objectivity of calculating the jump layer thickness. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 A flow chart showing a comprehensive processing method for extracting the depth of an ocean mixed layer according to an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] At present, most of the calculation methods of the mixed layer depth are limited to the gradient threshold, which subjectively limits the temperature change trend in the mixed layer to a fixed threshold range, and is not applicable to various regions and temperature profiles with complex change trends. The purpose of the present invention is to overcome the limitations of the existing mixed layer depth calculation methods and provide a calculation method of the set linear fitting and temperature standard deviation.

[0051] In the embodiment of the present invention, the temperature profile measured by Argo is used to fit the temperature profile equation of different seasons, and the fitting curve is calculated by combining linear fitting with temperature standard deviation to extract the depth of the ocean mixed layer, thereby avoiding the situation where the subjective setting of the temperature gradient threshold is not applicable to complex ocean profiles. The objectivity of calculating the thermocline thickness is greatly increased, and the method is applicable to various regions.

[0052] like Figure 1 As shown, Figure 1A flow chart showing a comprehensive processing method for extracting the depth of an ocean mixed layer according to an embodiment of the present invention.

[0053] Figure 1 A comprehensive processing method for extracting the depth of the ocean mixed layer includes:

[0054] S101. Collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data;

[0055] S102, interpolating the ocean temperature profile after quality control to determine the depth at which the interpolation result reaches a resolution of a first set value;

[0056] S103, using a straight line approximation algorithm to calculate the first mixed layer depth D1 of the ocean to be detected;

[0057] S104. Calculate the characteristic parameters of the ocean profile to be detected by using the temperature standard deviation γ(n) at different depths. Obtaining a second mixed layer depth D2;

[0058] S105. Compare two possible mixing layer depths. When the first mixing layer depth D1 is greater than the second mixing layer depth D2, select the first mixing layer depth D1 as the final mixing layer depth. When the second mixing layer depth D2 is greater than or equal to the first mixing layer depth D1, take the second mixing layer depth D2 as the final mixing layer depth.

[0059] In an embodiment of the present invention, a comprehensive processing method for extracting the mixed layer depth can calculate the mixed layer depth more objectively and can be applied to various complex situations of the global ocean profile, rather than being limited to a single critical threshold.

[0060] In one embodiment of the present invention, interpolation processing is performed on the ocean temperature profile after quality control to determine the depth at which the interpolation result reaches a resolution of a first set value, including:

[0061] Using the cubic spline interpolation method, all profiles after quality control are interpolated to above 0 m, 1 m, 2 m, 3 m, ..., 1000 m, so that their vertical resolution reaches the first set value;

[0062] During the interpolation process, since the first point of the ocean temperature profile is on the sea surface of the ocean to be measured, the first data point on each ocean temperature profile is set as the sea surface data for interpolation.

[0063] In one embodiment of the present invention, a linear approximation algorithm is used to calculate the first mixed layer depth D1 of the ocean to be detected, including:

[0064] Assume that the seawater temperature distribution is T i, i represents depth; when i = 0, it represents sea surface temperature. Linear fitting is performed on the temperature profile, and the temperature corresponding to the depth of the data is obtained as And calculate the characteristic parameter δ(n):

[0065]

[0066] Where n represents the depth, when n = 0, it represents the sea surface temperature, T i is the temperature of the temperature profile at depth i, is the temperature at depth i of the fitting line;

[0067] Take the constant m=5 and calculate the characteristic parameter σ(n) of m data points below the fitting depth

[0068]

[0069] Where T is the temperature profile, is the temperature of the fitted straight line;

[0070] Calculate the ratio λ(n) of the characteristic parameter σ(n) to the characteristic parameter δ(n):

[0071]

[0072] When the ratio of the characteristic parameter δ(n) to the characteristic parameter σ(n) is the largest, the depth of the ocean to be detected is taken as the mixed layer depth D1.

[0073] In one embodiment of the present invention, the characteristic parameter is calculated by the temperature standard deviation γ(n) at different depths in the ocean profile to be detected. Obtaining the second mixed layer depth D2 includes:

[0074] Calculate the temperature standard deviation γ(n) at each depth of the ocean to be detected:

[0075]

[0076] Where n is the current depth, is the average seawater temperature above a depth of n meters;

[0077] Calculate feature parameters

[0078]

[0079] Among them, γ(n) is the standard deviation of temperature at a depth of n meters; γ(1.3×n) is 1.3 times the standard deviation of temperature at a depth of n meters; when the characteristic parameter When it is at its maximum, this depth is taken as the mixed layer depth D2.

[0080] In one embodiment of the present invention, collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data include:

[0081] Remove the ocean temperature profiles whose depth profiles cannot always increase and the ocean temperature profiles with more than 2 consecutive missing values;

[0082] The number of data points on the entire section line of the ocean temperature profile is greater than 50, and there are more than 2 data points between 10 meters and 40 meters.

[0083] In one embodiment of the present invention, collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data include:

[0084] Each ocean temperature profile has a sufficiently wide coverage area, with the minimum depth below 10 meters and the maximum depth above 1000 meters.

[0085] The ocean temperature is required to be between -2°C and 35°C, and the maximum temperature difference in the entire profile is greater than 1°C;

[0086] Among them, the maximum temperature difference between 0 and 20 meters is greater than the maximum temperature difference below 20 meters.

[0087] In one embodiment of the present invention, the first set value is 1 meter.

[0088] It can be understood that in other implementations of the embodiments of the present invention, the first set value can be adjusted as needed, specifically 0.5 meters, 1 meter, 1.5 meters, or 2 meters. The specific value is determined according to demand and is not specifically limited here.

[0089] In the embodiment of the present invention, the temperature profile data is collected worldwide, and the quality control of the temperature profile data is performed, which specifically includes:

[0090] Remove the profiles whose depth profiles cannot always increase and those with more than 2 consecutive missing values ​​to ensure credibility. In order to ensure that there are enough observation points in the profile, it is stipulated that the number of data points on the entire profile is greater than 50 and there are more than 2 data points between 10 meters and 40 meters. It is required that each profile has a sufficiently wide coverage range, the minimum depth within the profile is less than 10 meters and the maximum depth is greater than 1000 meters. In order to exclude abnormal temperature data, the temperature is required to be between -2℃ and 35℃ and the maximum temperature difference in the entire profile is greater than 1℃. In addition, it is required that the maximum temperature difference between 0 and 20 meters is greater than the maximum temperature difference below 20 meters.

[0091] In the embodiment of the present invention, the temperature profile after quality control is interpolated to a depth with a resolution of 1 meter, specifically including:

[0092] Using the cubic spline interpolation method, all profiles after quality control are interpolated to 0m, 1m, 2m, 3m, ..., 1000m, so that their vertical resolution is 1m. Since the first point of each profile is often on the sea surface during the interpolation process, there will be extrapolation near the sea surface, making the first data inaccurate. Therefore, the first data point on each profile is set as the sea surface data for interpolation.

[0093] In the embodiment of the present invention, the linear approximation algorithm is used to calculate the depth of the first mixed layer, which specifically includes:

[0094] Linear fitting is performed on the temperature data from the sea surface to each depth range one by one, and the calculated characteristic parameter δ(n) of these fitting lines and the temperature profile is calculated; then the calculated characteristic parameter σ(n) of the fitting lines and the temperature profile of the five data below the fitting depth is calculated; finally, the ratio λ(n) of the characteristic parameter δ(n) to the characteristic parameter σ(n) is calculated, and the depth at the maximum value of λ(n) is taken as the first mixed layer depth D1.

[0095] In another embodiment of the present invention, a comprehensive processing device for extracting the depth of an ocean mixed layer is provided, based on a comprehensive processing method for extracting the depth of an ocean mixed layer as described in any one of the above items, characterized in that the device comprises: a data collection module, an interpolation module, a first mixed layer depth module, a second mixed layer depth module and a processing module;

[0096] The data collection module is used to collect ocean temperature profile data worldwide and perform quality control on the ocean temperature profile data;

[0097] The interpolation module is used to interpolate the ocean temperature profile after quality control and determine the depth at which the interpolation result reaches a resolution of a first set value;

[0098] The first mixed layer depth module is used to calculate the first mixed layer depth D1 of the ocean to be detected using a straight line approximation algorithm;

[0099] The second mixed layer depth module is used to calculate its characteristic parameters through the temperature standard deviation γ(n) at different depths in the ocean profile to be detected. Obtaining a second mixed layer depth D2;

[0100] The processing module is used to compare two possible mixing layer depths. When the first mixing layer depth D1 is greater than the second mixing layer depth D2, the first mixing layer depth D1 is selected as the final mixing layer depth. When the second mixing layer depth D2 is greater than or equal to the first mixing layer depth D1, the second mixing layer depth D2 is taken as the final mixing layer depth.

[0101] In an embodiment of the present invention, a comprehensive processing method and device for extracting the depth of an ocean mixed layer are provided. The method collects ocean temperature profile data on a global scale and performs quality control on the ocean temperature profile data. The ocean temperature profile after quality control is interpolated to determine the depth at which the interpolation result reaches a resolution of a first set value. The first mixed layer depth of the ocean to be detected is calculated, and the second mixed layer depth is obtained by the temperature standard deviation at different depths in the ocean profile to be detected. Two possible mixed layer depths are compared, and when the first mixed layer depth is greater than the second mixed layer depth, the first mixed layer depth is selected as the final mixed layer depth; otherwise, the second mixed layer depth is taken as the final mixed layer depth.

[0102] The technical solution of the present invention can overcome the limitations of existing mixed layer depth calculation methods, avoid the situation where the subjective setting of temperature gradient threshold is not suitable for complex ocean profiles, and increase the objectivity of calculating the jump layer thickness.

[0103] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A comprehensive processing method for extracting the depth of the ocean mixed layer, characterized in that: The method comprises: S101. Collecting global ocean temperature profile data and performing quality control on the ocean temperature profile data; S102, interpolating the ocean temperature profile after quality control, and determining a depth at which the interpolation result reaches a resolution of a first set value; S103, using a straight line approximation algorithm to calculate the first mixed layer depth D1 of the ocean to be detected; S104. Calculate the characteristic parameters of the ocean profile to be detected by using the temperature standard deviation γ(n) at different depths. Obtaining a second mixed layer depth D2; S105. Compare two possible mixing layer depths. When the first mixing layer depth D1 is greater than the second mixing layer depth D2, select the first mixing layer depth D1 as the final mixing layer depth. When the second mixing layer depth D2 is greater than or equal to the first mixing layer depth D1, take the second mixing layer depth D2 as the final mixing layer depth.

2. A comprehensive processing method for extracting the depth of the ocean mixed layer according to claim 1, characterized in that: The ocean temperature profile after quality control is interpolated to determine the depth at which the interpolation result reaches a resolution of a first set value, including: Using the cubic spline interpolation method, all profiles after quality control are interpolated to above 0 m, 1 m, 2 m, 3 m, ..., 1000 m, so that their vertical resolution reaches the first set value; During the interpolation process, since the first point of the ocean temperature profile is on the sea surface of the ocean to be measured, the first data point on each ocean temperature profile is set as the sea surface data for interpolation.

3. The comprehensive processing method for extracting the depth of the ocean mixed layer according to claim 1 is characterized in that: The first mixed layer depth D1 of the ocean to be detected is calculated using a straight line approximation algorithm, including: Assume that the seawater temperature distribution is T i , i represents depth; when i = 0, it represents sea surface temperature. Linear fitting is performed on the temperature profile, and the temperature corresponding to the depth of the data is obtained as And calculate the characteristic parameter δ(n): Where n represents the depth, when n = 0, it represents the sea surface temperature, T i is the temperature of the temperature profile at depth i, is the temperature at depth i of the fitting line; Take the constant m=5 and calculate the characteristic parameter σ(n) of m data points below the fitting depth Where T is the temperature profile, is the temperature of the fitted straight line; Calculate the ratio λ(n) of the characteristic parameter σ(n) to the characteristic parameter δ(n): When the ratio of the characteristic parameter δ(n) to the characteristic parameter σ(n) is the largest, the depth of the ocean to be detected is taken as the mixed layer depth D1.

4. The comprehensive processing method for extracting the depth of the ocean mixed layer according to claim 1 is characterized in that: The characteristic parameters are calculated by the temperature standard deviation γ(n) at different depths in the ocean profile to be detected. Obtaining the second mixed layer depth D2 includes: Calculate the temperature standard deviation γ(n) at each depth of the ocean to be detected: Where n is the current depth, is the average seawater temperature above a depth of n meters; Calculate feature parameters Among them, γ(n) is the standard deviation of temperature at a depth of n meters; γ(1.3×n) is 1.3 times the standard deviation of temperature at a depth of n meters; when the characteristic parameter When it is maximum, the depth is taken as the mixed layer depth D2.

5. The comprehensive processing method for extracting the depth of the ocean mixed layer according to claim 1 is characterized in that: Collect global ocean temperature profile data and perform quality control on the ocean temperature profile data, including: Remove the ocean temperature profiles whose depth profiles cannot always increase and the ocean temperature profiles with more than 2 consecutive missing values; The number of data points on the entire section line of the ocean temperature profile is greater than 50, and there are more than 2 data points between 10 meters and 40 meters.

6. The comprehensive processing method for extracting the depth of the ocean mixed layer according to claim 1 is characterized in that: Collect global ocean temperature profile data and perform quality control on the ocean temperature profile data, including: Each ocean temperature profile has a sufficiently wide coverage area, with the minimum depth below 10 meters and the maximum depth above 1000 meters. The ocean temperature is required to be between -2°C and 35°C, and the maximum temperature difference in the entire profile is greater than 1°C; Among them, the maximum temperature difference between 0 and 20 meters is greater than the maximum temperature difference below 20 meters.

7. The comprehensive processing method for extracting the depth of the ocean mixed layer according to claim 1 is characterized in that: The first set value is 1 meter.

8. A comprehensive processing device for extracting the depth of an ocean mixed layer, based on a comprehensive processing method for extracting the depth of an ocean mixed layer as claimed in any one of claims 1 to 7, characterized in that: The device comprises: a data collection module, an interpolation module, a first mixed layer depth module, a second mixed layer depth module and a processing module; The data collection module is used to collect ocean temperature profile data worldwide and perform quality control on the ocean temperature profile data; The interpolation module is used to interpolate the ocean temperature profile after quality control and determine the depth at which the interpolation result reaches a resolution of a first set value; The first mixed layer depth module is used to calculate the first mixed layer depth D1 of the ocean to be detected using a straight line approximation algorithm; The second mixed layer depth module is used to calculate its characteristic parameters through the temperature standard deviation γ(n) at different depths in the ocean profile to be detected. Obtaining a second mixed layer depth D2; The processing module is used to compare two possible mixing layer depths. When the first mixing layer depth D1 is greater than the second mixing layer depth D2, the first mixing layer depth D1 is selected as the final mixing layer depth. When the second mixing layer depth D2 is greater than or equal to the first mixing layer depth D1, the second mixing layer depth D2 is taken as the final mixing layer depth.

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