Sea typhoon center identification method based on fusion data

Abstract

The invention discloses a sea typhoon center identification method based on fusion data, and relates to the technical field of satellite and forecast data analysis, and the method comprises the steps: obtaining satellite data and typhoon numerical model forecast data, and carrying out the matching of the satellite data and the typhoon numerical model forecast data according to time and height; performing fusion processing on the matched satellite data and typhoon numerical model forecast data to obtain a potential typhoon area; determining a typhoon center area image from the potential typhoon area, and determining a typhoon center position from the typhoon center area image; and performing coordinate conversion on the typhoon center position, and converting the typhoon center position after coordinate conversion into latitude and longitude values. According to the invention, accurate identification and real-time monitoring of the center position of the typhoon can be improved.

Description

Technical Field

[0001] This invention relates to the field of satellite and forecast data analysis technology, specifically to a method for identifying the center of a typhoon at sea based on fused data. Background Technology

[0002] Typhoons are a type of tropical cyclone with extremely strong destructive power, severely impacting the climate and ecological environment of coastal areas. With the intensification of climate change, the frequency and intensity of typhoons are also increasing. Developing typhoon monitoring, forecasting, and early warning services; exploring the interaction between typhoons and the ocean; conducting typhoon-scale research; and striving to improve forecasting techniques are all crucial scientific research areas for typhoon prevention and disaster mitigation. Specifically, the interaction between typhoons and the ocean mainly includes: the atmosphere absorbing energy from the ocean to form typhoons; typhoons significantly altering the characteristics of the upper ocean; and the altered ocean then exerting new influences on typhoons. This interaction is specifically manifested in the intensity of heat, water vapor, and momentum exchange between typhoons and the ocean, which not only determine the intensity and scale of typhoons but also constrain their maximum possible intensity.

[0003] Currently, typhoon identification technology mainly relies on methods such as radar and aircraft observation. Aircraft reconnaissance provides relatively accurate information on typhoon location and intensity, but its high cost limits the frequency and geographical scope of such operations. Radar technology determines the typhoon's intensity and center location based on radar echoes from its spiral rainbands. Radar is a crucial detection method when typhoons approach coastlines and islands, but its effectiveness is limited when typhoons are far from these areas. Conventional meteorological observations from coastal and island weather stations, ships, and floating weather stations cannot provide real-time and effective monitoring of typhoons due to their large radius and movement range.

[0004] Meteorological satellites can capture clear images of typhoon clouds in both visible and infrared light. Although their accuracy in determining the typhoon center is not as high as that of aircraft reconnaissance, their frequent and wide-ranging observations have made them the primary means of typhoon monitoring. Therefore, how to identify the typhoon center based on observed meteorological satellite data is a pressing technical problem that needs to be solved. Summary of the Invention

[0005] This invention provides a method for identifying the center of a typhoon at sea based on fused data. Based on observed meteorological satellite data and model forecast data, this method can improve the accuracy of typhoon center location identification and real-time monitoring by integrating the fine resolution of data sources, which is an improvement over typhoon identification based solely on satellite data.

[0006] This invention provides a method for identifying the center of a typhoon at sea based on fused data, including: Acquire satellite data and typhoon numerical model forecast data, and match the satellite data and typhoon numerical model forecast data according to time and altitude respectively; The matched satellite data and typhoon numerical model forecast data are fused to obtain potential typhoon areas. Image of the typhoon center region from potential typhoon areas; image of the typhoon center region from the typhoon center region; The coordinates of the typhoon's center are transformed, and the transformed typhoon center position is converted into latitude and longitude values.

[0007] In some instances, the acquisition of satellite data and typhoon numerical model forecast data includes: Extract infrared channel brightness temperature data and cloud top height information from satellite data; Short-term forecast temperature data at multiple altitude levels were extracted from typhoon numerical model forecast data.

[0008] In some instances, the matching of satellite data and typhoon numerical model forecast data according to time and altitude includes: Based on the time of the satellite data, select the temperature from the numerical model forecast data for the corresponding time. Temperature data from numerical model forecasts at similar altitudes at the same time were selected based on cloud top height information from satellite data.

[0009] In some instances, the fusion of matched satellite data and typhoon numerical model forecast data to obtain potential typhoon areas includes: Based on the temperature and satellite brightness temperature data of the matched typhoon numerical model forecast data, a polynomial interpolation method is used to interpolate the satellite brightness temperature data to the temperature spatial points of the typhoon numerical model forecast data to form fused data. The areas in the fused data with brightness temperatures lower than the preset value are selected as potential typhoon areas.

[0010] In some instances, determining the typhoon center region image from a potential typhoon area includes: Based on the potential typhoon areas selected from the fused data, and according to the isotherm distribution, the central area of ​​the isotherms is selected as the typhoon center area image.

[0011] In some instances, determining the location of the typhoon center from an image of the typhoon's central region includes: The location of the typhoon center in the image was determined by fitting the spiral equation positioning method.

[0012] In some instances, the coordinate transformation of the typhoon center location includes: The Log spiral is transformed into a Cartesian coordinate system to perform coordinate transformation on the typhoon's center location.

[0013] In some instances, converting the coordinate-transformed typhoon center location into latitude and longitude values ​​includes: Based on the resolution of the fused data, the grid index values ​​corresponding to X and Y are converted into latitude and longitude values ​​to obtain the location of the typhoon center.

[0014] In some instances, the method further includes: Write the typhoon's center location number, time, longitude, latitude, and the sea area it belongs to into the typhoon information history file.

[0015] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects: This invention addresses the disadvantage of scarce maritime data by combining the advantages of real-time satellite observation and the refined coverage of numerical weather prediction data to identify the typhoon's central region. This has profound significance for the scientific defense of ships at sea against typhoons and for strengthening disaster prevention and mitigation. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the method flow provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of another method flow provided in an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] In the following description, specific embodiments of the invention will be illustrated with reference to steps and symbols performed by one or more computers, unless otherwise stated. Therefore, these steps and operations will be referred to several times as being performed by a computer, and computer execution as referred to herein includes operations by a computer processing unit representing electronic signals of data in a structured format. This operation transforms the data or maintains it at a location in the computer's memory system, which can be reconfigured or otherwise alter the operation of the computer in a manner well known to those skilled in the art. The data structure maintained by the data is the physical location of the memory, which has specific characteristics defined by the data format. However, the principles of the invention described above are not intended to be limiting, and those skilled in the art will understand that many of the following steps and operations can also be implemented in hardware.

[0020] The terms "module" or "unit" as used herein can be considered as software objects executing on the computing system. Different components, modules, engines, and services described herein can be considered as implementations on the computing system. The apparatus and methods described herein are preferably implemented in software, but can also be implemented in hardware, both of which are within the scope of this invention.

[0021] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this specification means the presence of features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or wireless coupling. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0022] In the first embodiment of the present invention, a method for identifying the center of a typhoon at sea based on fused data is provided, such as... Figure 1 As shown, it includes the following steps: S101: Acquire satellite data and typhoon numerical model forecast data, and match the satellite data and typhoon numerical model forecast data according to time and altitude respectively; S102: The matched satellite data and typhoon numerical model forecast data are fused to obtain potential typhoon areas; S103: Determine the typhoon center area image from the potential typhoon area, and determine the typhoon center location from the typhoon center area image; S104: Perform coordinate transformation on the typhoon center location, converting the transformed typhoon center location into latitude and longitude values.

[0023] In this embodiment of the invention, step S101, acquiring satellite data and typhoon numerical model forecast data, includes: Extract infrared channel brightness temperature data and cloud top height information from satellite data; Short-term forecast temperature data at multiple altitude levels were extracted from typhoon numerical model forecast data.

[0024] Among them, typhoon numerical model data are calculation results output by numerical weather prediction models specifically used to simulate and forecast typhoon systems.

[0025] In this embodiment of the invention, step S101 involves matching satellite data and typhoon numerical model forecast data according to time and altitude, respectively, including: Based on the time of the satellite data, select the temperature from the numerical model forecast data for the corresponding time. Temperature data from numerical model forecasts at similar altitudes at the same time were selected based on cloud top height information from satellite data.

[0026] Time matching is used to ensure that the atmospheric state is being compared at the same moment and to avoid errors caused by time offset, while altitude matching is used to compare the temperature values ​​at the same altitude layer.

[0027] Numerical weather prediction models discretize the atmosphere from the surface to the top layer into dozens to hundreds of vertical layers. However, the cloud top height observed by satellite is usually not exactly equal to the precise height of a certain model layer. Therefore, the "closest height layer" represents the layer in the model whose height is closest to the cloud top height.

[0028] In this embodiment of the invention, step S102 involves fusing the matched satellite data and typhoon numerical model forecast data to obtain potential typhoon areas, including: Based on the temperature and satellite brightness temperature data of the matched typhoon numerical model forecast data, a polynomial interpolation method is used to interpolate the satellite brightness temperature data to the temperature spatial points of the typhoon numerical model forecast data to form fused data. The areas in the fused data with brightness temperatures lower than the preset value are selected as potential typhoon areas.

[0029] Satellite brightness temperature data originates from satellite sensors, and its spatial location is determined by the satellite's scanning geometry. These locations are typically not on a regular grid, but rather from numerical weather prediction model data (temperature results). During operation, the model outputs values ​​of its internal state variables (such as temperature) on a pre-defined regular three-dimensional grid. These grid points are fixed and regular (e.g., latitude and longitude grids, Gaussian grids, etc.). Since satellite data points usually do not fall precisely at the locations of numerical model grid points, to obtain an estimate of the satellite brightness temperature at a model grid point, it is necessary to estimate the brightness temperature value at that grid point using actual satellite observations around the grid point. This estimation process is called interpolation.

[0030] Among them, polynomial interpolation is a specific mathematical interpolation method that assumes that within a local region (e.g., the region consisting of several satellite observation points around a model grid point), the variation of data values ​​(here referring to brightness temperature) with spatial location (such as longitude and latitude) can be approximated by a polynomial function (such as linear, quadratic, or cubic polynomial).

[0031] In other words, because the brightness temperature data points measured by satellites and the temperature data points calculated by numerical models do not coincide on the Earth's surface (satellite points are irregular and dense, while model points are on a regular grid), a polynomial mathematical method is needed to estimate the brightness temperature value that the satellite would observe if it were located at a specific model grid point, based on the brightness temperature values ​​actually measured by the satellite around those points. In this way, the brightness temperature observed by the satellite and the temperature value calculated by the model have exactly the same spatial location (both are on the model grid points), allowing for direct comparison, verification, or fusion into the model (data assimilation).

[0032] In this process, after interpolating satellite brightness temperature data into the grid points of the typhoon numerical model, the actual data fusion process is achieved through data assimilation, which can be based on meteorological principles and mathematical optimization methods.

[0033] In this embodiment of the invention, step S103, determining the typhoon center region image from the potential typhoon region, includes: Based on the potential typhoon areas selected from the fused data, and according to the isotherm distribution, the central area of ​​the isotherms is selected as the typhoon center area image.

[0034] In this embodiment of the invention, step S103, determining the location of the typhoon center from the typhoon center region image, includes: The location of the typhoon center in the image was determined by fitting the spiral equation positioning method.

[0035] In this embodiment of the invention, step S104 involves performing coordinate transformation on the typhoon center position, including: The Log spiral is transformed into a Cartesian coordinate system to perform coordinate transformation on the typhoon's center location.

[0036] In this embodiment of the invention, step S104, converting the coordinate-transformed typhoon center position into latitude and longitude values, includes: Based on the resolution of the fused data, the grid index values ​​corresponding to X and Y are converted into latitude and longitude values ​​to obtain the location of the typhoon center.

[0037] In this embodiment of the invention, the method further includes: Write the typhoon's center location number, time, longitude, latitude, and the sea area it belongs to into the typhoon information history file.

[0038] In the second embodiment of the present invention, another method for identifying the center of a typhoon at sea based on fused data is also provided, such as... Figure 2 As shown, it includes the following steps: S01: Satellite Data Reading: Input satellite data and extract infrared channel brightness temperature data (e.g., 10.5~12.5μm) and cloud top height information; S02: Typhoon numerical model data reading: Input short-term forecast temperature data at multiple altitude levels of the numerical model; S03: Data grid spatiotemporal interval fusion matching: First, time matching is performed. Based on the time of the satellite data, the numerical model temperature result at the corresponding time is selected. Second, spatial altitude layer matching is performed. Based on the altitude layer information of the satellite data, the numerical model temperature result at the same time and similar altitude layer is selected. S04: Spatial grid horizontal resolution processing. Based on the above time and altitude layer matching, the satellite data and numerical model forecast results are matched: According to the numerical forecast model results and satellite brightness temperature data results, the current satellite brightness temperature data is interpolated to the spatial points of the numerical forecast model data temperature results to form fused data. The area with brightness temperature less than 245K in the fused data is selected as the potential typhoon area. S05: Shape determination of the typhoon center region: Based on the potential typhoon regions selected from the fused data, and according to the isotherm distribution, the isotherm center region is selected as the typhoon center region image for that region. S06: Determining the typhoon center location in an image using the spiral equation positioning method: When the cloud top temperature gradient in the image has a maximum alignment relationship with the logarithmic spiral vector emanating from the center point, the starting point of the logarithmic spiral vector is the typhoon center location. The logarithmic spiral equation in polar coordinates is: (1) in, is the radial distance from the origin of the typhoon center, m is the distance between the origin and the starting position of the spiral, and n is... The angle between the helical tangent and the radial line.

[0039] S07: Coordinate System Transformation: The Log spiral coordinate system is transformed into a Cartesian coordinate system. When the origin of the grid in the region to be analyzed is (0,0), the transformation formula is as follows: (2) (3) In the Northern Hemisphere, starting from the origin, the X-axis points eastward and the Y-axis points northward. In the Southern Hemisphere, the X-axis is the same as in the Northern Hemisphere, but the Y-axis is reversed.

[0040] S08: Confirm the center location using latitude and longitude coordinates: Based on the resolution of the fused data, convert the grid index values ​​corresponding to X and Y into latitude and longitude values ​​to obtain the typhoon center location; S09: Based on the results of automatic positioning and optimal typhoon analysis, write the typhoon center location number, time, longitude, latitude, and sea area information into the typhoon information history file.

[0041] This invention provides a method for identifying and monitoring the center of a typhoon at sea based on satellite data, through the above-described technical solution. This method is of profound significance for scientifically defending against typhoons and strengthening disaster prevention and mitigation. It can improve the accuracy of typhoon forecasts and safeguard people's lives and property.

[0042] The above provides a detailed description of a method for identifying the center of a typhoon at sea based on fused data, as provided in the embodiments of the present invention. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for identifying the center of a typhoon at sea based on fused data, characterized in that, include: Acquire satellite data and typhoon numerical model forecast data, and match the satellite data and typhoon numerical model forecast data according to time and altitude respectively; The matched satellite data and typhoon numerical model forecast data are fused to obtain potential typhoon areas. Image of the typhoon center region from potential typhoon areas; image of the typhoon center region from the typhoon center region; The coordinates of the typhoon's center are transformed, and the transformed typhoon center position is converted into latitude and longitude values.

2. The identification method according to claim 1, characterized in that, The acquisition of satellite data and typhoon numerical model forecast data includes: Extract infrared channel brightness temperature data and cloud top height information from satellite data; Short-term forecast temperature data at multiple altitude levels were extracted from typhoon numerical model forecast data.

3. The identification method according to claim 2, characterized in that, The process of matching satellite data and typhoon numerical model forecast data according to time and altitude includes: Based on the time of the satellite data, select the temperature from the numerical model forecast data for the corresponding time. Temperature data from numerical model forecasts at similar altitudes at the same time were selected based on cloud top height information from satellite data.

4. The identification method according to claim 3, characterized in that, The process of fusing the matched satellite data and typhoon numerical model forecast data to obtain potential typhoon areas includes: Based on the temperature and satellite brightness temperature data of the matched typhoon numerical model forecast data, a polynomial interpolation method is used to interpolate the satellite brightness temperature data to the temperature spatial points of the typhoon numerical model forecast data to form fused data. The areas in the fused data with brightness temperatures lower than the preset value are selected as potential typhoon areas.

5. The identification method according to claim 4, characterized in that, The process of determining the typhoon center region image from potential typhoon areas includes: Based on the potential typhoon areas selected from the fused data, and according to the isotherm distribution, the central area of ​​the isotherms is selected as the typhoon center area image.

6. The identification method according to claim 5, characterized in that, Determining the location of the typhoon center from the image of the typhoon center region includes: The location of the typhoon center in the image was determined by fitting the spiral equation positioning method.

7. The identification method according to claim 6, characterized in that, The coordinate transformation of the typhoon center location includes: The Log spiral is transformed into a Cartesian coordinate system to perform coordinate transformation on the typhoon's center location.

8. The identification method according to claim 7, characterized in that, The process of converting the coordinate-transformed typhoon center location into latitude and longitude values ​​includes: Based on the resolution of the fused data, the grid index values ​​corresponding to X and Y are converted into latitude and longitude values ​​to obtain the location of the typhoon center.

9. The identification method according to any one of claims 1 to 8, characterized in that, The method further includes: Write the typhoon's center location number, time, longitude, latitude, and the sea area it belongs to into the typhoon information history file.

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