Antarctic iceberg volume estimation method and system based on optical remote sensing image

Abstract

The invention discloses an Antarctic iceberg surrounding volume estimation method and system based on an optical remote sensing image, and the method comprises the steps: obtaining optical remote sensing image data, and partitioning the optical remote sensing image surrounding the Antarctic iceberg to form a plurality of fan-shaped regions; extracting a plurality of icebergs and iceberg shadows based on the optical remote sensing image data of each fan-shaped region; estimating the water outlet height of each iceberg based on the plurality of icebergs and the iceberg shadows; calculating the overwater volume of each iceberg by combining the iceberg area obtained by extracting the iceberg contour based on the water outlet height of each iceberg, and calculating the total volume of each iceberg by combining the Archimedes buoyancy law; according to the total volume of each iceberg, the total volume of all the icebergs in the corresponding sector area is obtained, and then the total volume of the icebergs around the Antarctic pole is obtained through calculation. According to the method, the iceberg volume calculation accuracy is improved, and more accurate scientific data and theoretical support are provided for global climate change research, polar region ecological environment protection and international shipping safety.

Description

Technical Field

[0001] The invention belongs to the field of geodetic photogrammetry and remote sensing, and in particular relates to a method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images. Background Art

[0002] As an important part of the global climate system, the existence and dynamic changes of icebergs in the Antarctic region have a profound impact on the global climate, ocean circulation and ecological environment. As a mobile source of fresh water in the ocean, icebergs store a large amount of fresh water resources. Their melting not only injects fresh water into the surrounding seas, but also has a significant impact on the physical and chemical properties of the ocean. Icebergs play a key role in the global climate change process by changing the temperature and salt structure of seawater, affecting ocean currents, the thickness of the ocean mixed layer and the global thermohaline circulation. The melting process of icebergs not only affects parameters such as ocean surface temperature and salinity, but also changes the albedo of the ocean, enhances the feedback effect of climate warming, and becomes an important clue in the study of polar and global climate change. Therefore, long-term observation and accurate measurement of iceberg volume changes are crucial to assessing the progress of global climate change.

[0003] The volume of an iceberg is one of the key parameters for studying the effect of icebergs on the climate system. It directly affects the buoyancy and thermal balance of the iceberg, and thus determines the movement trajectory, drift speed and melting rate of the iceberg in the ocean. The volume change of the iceberg not only affects the amount of fresh water injected into the surrounding sea area, but also dominates the energy and material exchange process between the iceberg and the atmosphere and ocean. These changes will have feedback effects on polar ecosystems, ocean circulation dynamics and the global climate system. Therefore, accurately obtaining information on the volume of icebergs and their changes is not only of great significance to the study of global climate and environmental changes, but also provides a scientific basis for the optimization of climate models, polar ecological environmental protection and international shipping safety.

[0004] Although the observation of iceberg volume is of great value to climate research and environmental protection, the measurement of iceberg volume is full of challenges. At present, the methods for obtaining iceberg volume mainly include field measurement, ship-borne observation, airborne lidar, satellite remote sensing, etc. Although traditional field measurement and ship-borne and airborne observation methods can provide detailed information about icebergs in local areas, it is difficult to achieve continuous observation over a large range. Satellite altimetry technology can cover a larger range and monitor icebergs for a long time. By observing the surface elevation of icebergs and combining the principle of hydrostatic equilibrium, the volume of icebergs can be estimated. However, since parameters such as the thickness of snow on the surface of icebergs, snow density, and ice body density are difficult to measure accurately under polar conditions, the error in volume estimation is large. In addition, factors such as the ability of radar signals to penetrate the ice and snow layer and the boundary conditions between icebergs and seawater also bring uncertainty to the calculation of iceberg volume. Therefore, how to reduce the uncertainty of these parameters and improve the accuracy of iceberg volume measurement is the main problem facing the current field of iceberg volume monitoring. Summary of the invention

[0005] In order to overcome the deficiencies of the above-mentioned prior art, the present invention provides a method and system for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images, which are used to calculate the volume of circum-Antarctic icebergs and improve the accuracy of iceberg volume calculation, thereby providing more accurate scientific data and theoretical support for global climate change research, polar ecological environmental protection and international shipping safety.

[0006] According to one aspect of the present invention, a method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images is provided, comprising: Obtain optical remote sensing image data and divide the optical remote sensing images of Antarctic icebergs into several fan-shaped areas; Based on the optical remote sensing image data of each sector area, a number of icebergs and iceberg shadows are extracted; Based on the icebergs and their shadows, estimate the height above water of each iceberg; Based on the water height of each iceberg, combined with the iceberg area obtained by extracting the iceberg contour, the above-water volume of each iceberg is calculated, and the total volume of each iceberg is calculated in combination with Archimedes' law of buoyancy; Based on the total volume of each iceberg, the total volume of all icebergs in the corresponding fan-shaped area is obtained, and based on the total volume of icebergs in all fan-shaped areas, the total volume of circum-Antarctic icebergs is calculated.

[0007] As a further technical solution, based on the optical remote sensing image data, extracting icebergs and iceberg shadows includes: According to the normalized shadow index, iceberg shadows are identified and preliminary shadow classification results are obtained; The iceberg contours were calculated using the iceberg texture features to obtain preliminary iceberg classification results. In the preliminary iceberg classification results, the overlapping parts of the iceberg and the preliminary shadow classification results are deleted, and the shadow part of the iceberg is retained; Using the solar azimuth information in the optical image, the azimuth of the iceberg shadow is determined, and according to the azimuth of the iceberg shadow, shadow checks are performed on the iceberg classification results and the shadow classification results respectively to obtain checked iceberg classification results and shadow classification results; Based on the iceberg classification results and shadow classification results after the inspection, the missing values ​​are filled to obtain the final iceberg and iceberg shadow.

[0008] As a further technical solution, based on the icebergs and their shadows, the height of each iceberg above the water is estimated, including: Convert the extracted icebergs and iceberg shadows from pixels into vector objects; The shadow length along the solar azimuth direction was calculated from the edge of each iceberg; Based on the constructed shadow altimetry model, the height above water of each iceberg was calculated.

[0009] As a further technical solution, the shadow length along the solar azimuth direction is calculated with the edge of each iceberg as the starting point, including: A number of shadow points and shadow edge points are extracted along the solar azimuth direction at the edge of the iceberg, and the shadow length is calculated based on the extracted number of shadow points and shadow edge points.

[0010] As a further technical solution, the height above water of each iceberg is calculated, which also includes: Based on the line connecting the shadow point and the shadow edge point, the iceberg is cut into several parts, and the water height of each part is obtained by the length of the connecting line of the part.

[0011] According to one aspect of the present invention, there is provided a system for estimating the volume of Antarctic icebergs based on optical remote sensing images, comprising: The first main module is used to obtain optical remote sensing image data and divide the optical remote sensing image of the Antarctic iceberg into blocks to form a number of fan-shaped areas; The second main module is used to extract a number of icebergs and iceberg shadows based on the optical remote sensing image data of each sector area; A third main module is used for estimating the water height of each iceberg based on the icebergs and their shadows; The fourth main module is used to calculate the above-water volume of each iceberg based on the water height of each iceberg and the iceberg area obtained by extracting the iceberg contour, and calculate the total volume of each iceberg in combination with Archimedes' law of buoyancy; The fifth main module is used to obtain the total volume of all icebergs in the corresponding fan-shaped area based on the total volume of each iceberg, and to calculate the total volume of the circum-Antarctic icebergs based on the total volume of icebergs in all fan-shaped areas.

[0012] According to one aspect of the present invention, there is provided a device for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images, comprising a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images.

[0013] According to one aspect of the present specification, there is provided a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions enable the computer to execute the steps of the method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The present invention calculates the volume of Antarctic icebergs based on optical remote sensing images, specifically extracting icebergs and iceberg shadows based on optical remote sensing image data, estimating the height of the iceberg above water based on the extracted icebergs and iceberg shadows, and then calculating the above-water volume of the iceberg based on the height of the iceberg above water combined with the iceberg area obtained by extracting the iceberg contour, and calculating the total volume of the iceberg combined with Archimedes' law of buoyancy. The present invention solves the problem of estimating the volume of an iceberg through uncertain parameters and improves the accuracy of iceberg volume calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction is given below to the drawings used in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A schematic flow chart of a method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images provided in an embodiment of the present invention.

[0017] Figure 2 A schematic diagram of remote sensing images from the Zhongshan Station sea area to the Cape Goodenough sea area from July to September 2016 provided in an embodiment of the present invention.

[0018] Figure 3 An example schematic diagram of a classification result map within the sea area from Zhongshan Station to Cape Goodenough from July to September 2016 provided in an embodiment of the present invention.

[0019] Figure 4 A schematic diagram of an example of a partial iceberg volume result diagram within the range from Zhongshan Station to Cape Goodenough from July to September 2016 provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions, for example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to the steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in 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. In addition, the technical features in the various embodiments or single embodiments provided by the present invention are arbitrarily combined with each other to form a new technical solution. This combination is not restricted by the sequence of steps and / or the structural composition mode, but must be based on the ability of ordinary technicians in this field to achieve. When the combination of technical solutions is contradictory or cannot be achieved, it should be considered that this combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] The method for estimating the volume of Antarctic icebergs based on optical remote sensing images provided in the embodiment of the present invention includes four steps. The calculation process is as follows: Figure 1 As shown: Step 1: Optical remote sensing image data processing.

[0023] Based on LandSat 8 optical remote sensing image data, this embodiment takes the Antarctic sea ice area as an example and extracts various remote sensing images from the Zhongshan Station to Cape Goodenough from July to September 2016. Figure 2 As shown in the figure, the image area accounts for about 1 / 6 of the Antarctic region. The image contains information on each band, solar altitude angle, solar azimuth angle, longitude and latitude, etc.

[0024] Furthermore, step 1 also includes: processing the optical remote sensing image in blocks to form a number of fan-shaped areas, the specific size of which depends on the cloud cover, terrain features, etc. The difference in satellite imaging in different areas is reduced by block extraction, thereby improving the recognition accuracy of iceberg contours and iceberg shadows based on optical satellite remote sensing data.

[0025] Furthermore, for each sector-shaped area, icebergs and their shadows were extracted, the height of icebergs above water was estimated, and the volume of icebergs was calculated. Then, the total volume of circum-Antarctic icebergs was obtained based on the volume of icebergs in each sector-shaped area.

[0026] Step 2, extraction of icebergs and iceberg shadows, includes the following sub-steps: Step 2.1: Identify the iceberg shadow based on the normalized shadow index. The normalized shadow index is defined as:

[0027] In the formula The near-infrared band, The blue band. The shadow coverage area threshold can be obtained by calculation to extract the shadow outline, which is the preliminary iceberg shadow classification result.

[0028] Since the threshold segmentation method has a high accuracy in iceberg shadow classification, the shadow area is mainly focused in the initial extraction process. By comparison, it is found that the NSPI threshold in this area can be set at around -0.4. The higher the shadow degree, the smaller the NSPI, and the lower the shadow degree, the larger the NSPI. The NSPI value needs to be set by manually comparing the band values ​​of the shadow area and the non-shadow area and slowly adjusting. The shadow outline extracted by the threshold is the preliminary shadow classification result.

[0029] Step 2.2, using the texture features of the iceberg, a rougher iceberg outline can be calculated, which is the preliminary iceberg classification result.

[0030] First, we need to calculate the grayscale value of the remote sensing image and then extract the iceberg by contrast. The formula for calculating contrast is:

[0031] Where Gray is the gray value, The near-infrared band, is the red band, The .glcmTexture() function is then called to calculate the layer contrast. By comparison, it can be found that the iceberg contrast threshold can be set at around 30. The larger the value, the stronger the texture, and vice versa.

[0032] Step 2.3, in the iceberg classification results, delete the parts that overlap with the shadow classification results. Keep the overlapping parts of the shadow classification results to ensure that the high-precision classification results of the iceberg shadow are accurately retained. The purpose of this step is to eliminate possible classification errors and optimize the separation effect of icebergs and shadows.

[0033] Step 2.4, using the solar azimuth information in the optical image, determine the azimuth of the iceberg shadow. Check whether there is a shadow on the back side of the iceberg according to this azimuth. If a shadow is detected, keep the result; if no shadow is found, discard the result. At the same time, perform a similar check on the shadow classification result to ensure that there is an iceberg nearby.

[0034] Step 2.5, fill in the missing values ​​in the extraction results of icebergs and their shadows. Since the icebergs around the Antarctic are all convex polygons, data interpolation or other technical means can be used to convert the concave polygons in the classification results into convex polygons, improve the integrity of the icebergs and their shadow areas, and improve the quality of the overall extraction results. For example, a function can be used to fill the classification results, and the objects that are concave polygons in the iceberg classification results are turned into convex polygons. At the same time, fill in the missing values ​​or error values ​​inside, because there will be no other classification results inside the classification results, such as inside the iceberg. This operation can improve the accuracy of the extraction of icebergs and iceberg shadows. The final classification result diagram (part) is as follows Figure 3 As shown, the blue is the iceberg and the green is the shadow.

[0035] It should be noted that in step 2, the normalized shadow index NSPI is used as a parameter to identify the shadow of the iceberg. At the same time, the iceberg and the iceberg shadow are combined to eliminate errors and improve accuracy. This breaks away from the traditional method of measuring the height of the iceberg above the water by satellite radar altimetry, avoids the problem of difficulty in covering the Antarctic region due to interval sampling of the satellite along the orbit, and expands the scope of iceberg volume calculation to the Antarctic region.

[0036] Step 3, estimating the height of the iceberg above the water, includes the following sub-steps: Step 3.1, convert the iceberg and iceberg shadow extracted in step 2 from pixel points into vector objects.

[0037] Step 3.2, taking the edge of each iceberg as the starting point, calculate the shadow length along the solar azimuth direction. The specific method is: first, extract the shadow points (the points where the iceberg classification results are connected to the shadow results) and the shadow edge points along the solar azimuth direction on the edge of the iceberg. You can take a number of points. The more points, the higher the accuracy, and thus calculate the shadow length.

[0038] Step 3.3, establish the following shadow height measurement model:

[0039] Where L is the shadow length, H is the height of the iceberg above the water after deducting the thickness of the sea ice, and θ is the solar altitude angle. The optical image can be obtained from the Level-1T data product of the Landsat 8 satellite (source: https: / / www.usgs.gov), and the default satellite altitude angle of its data product is 90°.

[0040] The above formula can be used to calculate the height of the iceberg above the water using the shadow length obtained in step 3.2.

[0041] Step 4: The above-water volume of the iceberg can be calculated using the extracted iceberg height and the iceberg area obtained by extracting the iceberg outline. The area of ​​the iceberg can be calculated using pixels. It is known that the resolution of LandSat 8 remote sensing images is 30m, so the area of ​​a pixel is 900 square meters. Therefore, it is only necessary to calculate the number of pixels within the iceberg outline to obtain the iceberg area. The total volume of the iceberg can be calculated using Archimedes' law of buoyancy:

[0042] Since the surface of a large iceberg is relatively flat, the volume can be calculated by approximating it as a cylinder. The line connecting the shadow point and the shadow edge point in step 3.2 can cut the iceberg into several parts, and the height above the water of each part can be obtained by the length of the line connecting the part, so we can use The water volume is obtained. The total volume can then be calculated using the following formula.

[0043]

[0044] Icebergs are made of ice, the density of ice is about 917 kg / m³, while the density of seawater is about 1025 kg / m³, so we can calculate .

[0045] Figure 4 The volume results of some icebergs in the area from Zhongshan Station to Cape Goodenough from July to September 2016 are given.

[0046] The implementation basis of each embodiment of the present invention is to implement programmed processing through a device with a processor function. Therefore, in engineering practice, the technical solutions and functions of each embodiment of the present invention are encapsulated into various modules. Based on this reality, on the basis of the above embodiments, an embodiment of the present invention provides a system for estimating the volume of Antarctic icebergs based on optical remote sensing images, which is used to execute a method for estimating the volume of Antarctic icebergs based on optical remote sensing images in the above method embodiment.

[0047] The system includes: a first main module, which is used to obtain optical remote sensing image data and divide the optical remote sensing images of the circum-Antarctic icebergs into blocks to form a plurality of fan-shaped areas; a second main module, which is used to extract a plurality of icebergs and iceberg shadows based on the optical remote sensing image data of each fan-shaped area; a third main module, which is used to estimate the height above water of each iceberg based on the plurality of icebergs and iceberg shadows; a fourth main module, which is used to calculate the above-water volume of each iceberg based on the height above water of each iceberg combined with the iceberg area obtained by extracting the iceberg contour, and calculate the total volume of each iceberg combined with Archimedes' law of buoyancy; and a fifth main module, which is used to obtain the total volume of all icebergs in the corresponding fan-shaped area based on the total volume of each iceberg, and calculate the total volume of the circum-Antarctic icebergs based on the total volume of the icebergs in all fan-shaped areas.

[0048] An embodiment of the present invention provides a system for estimating the volume of Antarctic icebergs based on optical remote sensing images. In view of the current situation where the existing iceberg volume estimation method has low accuracy due to parameter uncertainty, the system adopts the above-mentioned modules to calculate the volume of Antarctic icebergs based on optical remote sensing images, thereby solving the problem of estimating the volume of icebergs through uncertain parameters and improving the accuracy of iceberg volume calculation.

[0049] It should be noted that the system embodiment provided by the present invention is used to implement the methods in the above method embodiment as well as the methods in other method embodiments provided by the present invention. The only difference is that the corresponding functional modules are set. The principle is basically the same as the principle of the above system embodiment provided by the present invention. As long as the technical personnel in this field refer to the specific technical solutions in other method embodiments on the basis of the above system embodiment, obtain the corresponding technical means and the technical solutions composed of these technical means by combining the technical features, and on the premise of ensuring the practicality of the technical solutions, improve the modules in the above system embodiment to obtain the corresponding system class embodiments, which are used to implement the methods in other method class embodiments. For example: Based on the content of the above system embodiment, as a preferred embodiment, in the embodiment of the present invention, a system for estimating the volume of Antarctic icebergs based on optical remote sensing images is provided, wherein the second main module is further used to execute the following instructions: According to the normalized shadow index, iceberg shadows are identified and preliminary shadow classification results are obtained; The iceberg contours were calculated using the iceberg texture features to obtain preliminary iceberg classification results. In the preliminary iceberg classification results, the overlapping parts of the iceberg and the preliminary shadow classification results are deleted, and the shadow part of the iceberg is retained; Using the solar azimuth information in the optical image, the azimuth of the iceberg shadow is determined, and according to the azimuth of the iceberg shadow, shadow checks are performed on the iceberg classification results and the shadow classification results respectively to obtain checked iceberg classification results and shadow classification results; Based on the iceberg classification results and shadow classification results after the inspection, the missing values ​​are filled to obtain the final iceberg and iceberg shadow.

[0050] Based on the content of the above system embodiment, as a preferred embodiment, in the embodiment of the present invention, a system for estimating the volume of Antarctic icebergs based on optical remote sensing images is provided, wherein the third main module is further used to execute the following instructions: Convert the extracted icebergs and iceberg shadows from pixels into vector objects; The shadow length along the solar azimuth direction was calculated from the edge of each iceberg; Based on the constructed shadow altimetry model, the height above water of each iceberg was calculated.

[0051] Based on the content of the above system embodiment, as a preferred embodiment, in the embodiment of the present invention, a system for estimating the volume of Antarctic icebergs based on optical remote sensing images is provided, wherein the third main module is further used to execute the following instructions: A number of shadow points and shadow edge points are extracted along the solar azimuth direction at the edge of the iceberg, and the shadow length is calculated based on the extracted number of shadow points and shadow edge points.

[0052] Based on the content of the above system embodiment, as a preferred embodiment, in the embodiment of the present invention, a system for estimating the volume of Antarctic icebergs based on optical remote sensing images is provided, wherein the third main module is further used to execute the following instructions: Based on the line connecting the shadow point and the shadow edge point, the iceberg is cut into several parts, and the water height of each part is obtained by the length of the connecting line of the part.

[0053] Based on the same inventive concept as the above-mentioned embodiment, an embodiment of the present invention also provides a device for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images, comprising a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images.

[0054] Based on the same inventive concept as the above-mentioned embodiment, an embodiment of the present invention further provides a non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium stores computer instructions, and the computer instructions enable the computer to execute the steps of the method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images.

[0055] In summary, the present invention takes into account the study of changes in the volume of Antarctic icebergs, which is usually done by calculating the area and thickness of the iceberg to obtain the volume of the iceberg. In existing research, few scholars have mentioned the calculation of the volume of icebergs in the entire Antarctic. This is because the remote sensing images of various regions around the Antarctic differ in the reflectivity of the ground objects, and the texture features and reflection characteristics of different ground objects are slightly different, so the present invention divides the Antarctic region into different fan-shaped areas for research. In addition, since the sampling of satellites equipped with laser altimeters or radar altimeter sensors is spaced along the orbit, it is difficult to cover the Antarctic region, so the measurement of iceberg elevation by satellite altimeter has certain limitations. Therefore, the present invention adopts the method of establishing a shadow altimeter model to calculate the height of the iceberg above the water, thereby improving the calculation accuracy and range of the overall height of the iceberg above the water around the Antarctic.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A method for estimating the volume of Antarctic icebergs based on optical remote sensing images, characterized in that: include: Obtain optical remote sensing image data and divide the optical remote sensing images of Antarctic icebergs into several fan-shaped areas; Based on the optical remote sensing image data of each sector area, a number of icebergs and iceberg shadows are extracted; Based on the icebergs and their shadows, estimate the height above water of each iceberg; Based on the water height of each iceberg, combined with the iceberg area obtained by extracting the iceberg contour, the above-water volume of each iceberg is calculated, and the total volume of each iceberg is calculated in combination with Archimedes' law of buoyancy; Based on the total volume of each iceberg, the total volume of all icebergs in the corresponding fan-shaped area is obtained, and based on the total volume of icebergs in all fan-shaped areas, the total volume of circum-Antarctic icebergs is calculated.

2. The method for estimating the volume of Antarctic icebergs based on optical remote sensing images according to claim 1, characterized in that: Extracting icebergs and iceberg shadows based on the optical remote sensing image data includes: According to the normalized shadow index, iceberg shadows are identified and preliminary shadow classification results are obtained; The iceberg contours were calculated using the iceberg texture features to obtain preliminary iceberg classification results. In the preliminary iceberg classification results, the overlapping parts of the iceberg and the preliminary shadow classification results are deleted, and the shadow part of the iceberg is retained; Using the solar azimuth information in the optical image, the azimuth of the iceberg shadow is determined, and according to the azimuth of the iceberg shadow, shadow checks are performed on the iceberg classification results and the shadow classification results respectively to obtain checked iceberg classification results and shadow classification results; Based on the iceberg classification results and shadow classification results after the inspection, the missing values ​​are filled to obtain the final iceberg and iceberg shadow.

3. The method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images according to claim 1, characterized in that: Based on a number of the icebergs and their shadows, estimate the height of each iceberg above the water, including: Convert the extracted icebergs and iceberg shadows from pixels into vector objects; The shadow length along the solar azimuth direction was calculated from the edge of each iceberg; Based on the constructed shadow altimetry model, the height above water of each iceberg was calculated.

4. The method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images according to claim 3 is characterized in that: The shadow length along the solar azimuth direction is calculated from the edge of each iceberg, including: A number of shadow points and shadow edge points are extracted along the solar azimuth direction at the edge of the iceberg, and the shadow length is calculated based on the extracted number of shadow points and shadow edge points.

5. The method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images according to claim 4, characterized in that: The height above water of each iceberg is calculated, including: Based on the line connecting the shadow point and the shadow edge point, the iceberg is cut into several parts, and the water height of each part is obtained by the length of the connecting line of the part.

6. An Antarctic iceberg volume estimation system based on optical remote sensing images, characterized in that: include: The first main module is used to obtain optical remote sensing image data and divide the optical remote sensing image of the Antarctic iceberg into blocks to form a number of fan-shaped areas; The second main module is used to extract a number of icebergs and iceberg shadows based on the optical remote sensing image data of each sector area; A third main module is used for estimating the water height of each iceberg based on the icebergs and their shadows; The fourth main module is used to calculate the above-water volume of each iceberg based on the water height of each iceberg and the iceberg area obtained by extracting the iceberg contour, and calculate the total volume of each iceberg in combination with Archimedes' law of buoyancy; The fifth main module is used to obtain the total volume of all icebergs in the corresponding fan-shaped area based on the total volume of each iceberg, and to calculate the total volume of the circum-Antarctic icebergs based on the total volume of icebergs in all fan-shaped areas.

7. A device for estimating the volume of Antarctic icebergs based on optical remote sensing images, characterized in that: It comprises a memory and a processor, wherein the memory stores program instructions executed by the processor, and the processor calls the program instructions to execute the steps of the method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images as described in any one of claims 1 to 5.

8. A non-transitory computer-readable storage medium, characterized in that: The non-transitory computer-readable storage medium stores computer instructions, and the computer instructions enable the computer to execute the steps of the method for estimating the volume of circum-Antarctic icebergs based on optical remote sensing images as described in any one of claims 1 to 5.

Images