CN112414554B - Sea surface salinity obtaining method, device, equipment and medium - Google Patents
Sea surface salinity obtaining method, device, equipment and medium Download PDFInfo
- Publication number
- CN112414554B CN112414554B CN202011413746.7A CN202011413746A CN112414554B CN 112414554 B CN112414554 B CN 112414554B CN 202011413746 A CN202011413746 A CN 202011413746A CN 112414554 B CN112414554 B CN 112414554B
- Authority
- CN
- China
- Prior art keywords
- reflectivity
- salinity
- space
- temperature data
- sea area
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000000034 method Methods 0.000 title claims abstract description 53
- 238000002310 reflectometry Methods 0.000 claims abstract description 128
- 238000004422 calculation algorithm Methods 0.000 claims description 58
- 238000012545 processing Methods 0.000 claims description 18
- 238000004364 calculation method Methods 0.000 claims description 17
- 238000012937 correction Methods 0.000 claims description 10
- 238000004590 computer program Methods 0.000 claims description 7
- 230000006870 function Effects 0.000 claims description 5
- 238000003306 harvesting Methods 0.000 claims 1
- 230000005855 radiation Effects 0.000 description 22
- 238000012546 transfer Methods 0.000 description 11
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 239000013535 sea water Substances 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000001351 cycling effect Effects 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000003491 array Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- JJWKPURADFRFRB-UHFFFAOYSA-N carbonyl sulfide Chemical compound O=C=S JJWKPURADFRFRB-UHFFFAOYSA-N 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 235000019800 disodium phosphate Nutrition 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000010287 polarization Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J5/00—Radiation pyrometry, e.g. infrared or optical thermometry
- G01J5/0003—Radiation pyrometry, e.g. infrared or optical thermometry for sensing the radiant heat transfer of samples, e.g. emittance meter
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- Geometry (AREA)
- General Engineering & Computer Science (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Radiation Pyrometers (AREA)
Abstract
The application provides a sea surface salinity obtaining method, a sea surface salinity obtaining device, sea surface salinity obtaining equipment and a sea surface salinity obtaining medium, and relates to the technical field of ocean exploration. The sea surface salinity obtaining method comprises the following steps: acquiring brightness temperature data of a target sea area in a preset waveband through a microwave radiometer; calculating the reflectivity of the target sea area in a preset wave band according to the brightness temperature data of the preset wave band; correcting the reflectivity of the target sea area in a preset waveband according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity; and performing salinity inversion according to the corrected reflectivity to obtain the sea surface salinity of the target sea area. According to the method, the reflectivity of the target sea area is corrected according to the time-space information of the brightness temperature data, and the inversion of the sea surface salinity is performed through the corrected reflectivity, so that the inversion precision is more accurate.
Description
Technical Field
The invention relates to the technical field of ocean exploration, in particular to a method, a device, equipment and a medium for acquiring sea surface salinity.
Background
Sea Surface Salinity (SSS) is the salinity concentration of sea surface seawater, and is closely related to the dielectric constant of seawater, which in turn determines the emissivity of seawater into the atmosphere. With the advent of satellite-borne microwave radiometers that directly measure the luminance Temperature (TB) data at the top of the atmosphere, theoretically, the correspondence between TB and SSS can be established by an atmospheric radiation transmission physical model and an offshore emissivity or reflectivity model.
Currently, the method for acquiring sea surface salinity is to acquire corresponding brightness temperature data, also called brightness temperature data, by using a satellite-borne microwave radiometer which runs in an on-orbit mode and produces business products, and then directly perform corresponding processing on the acquired brightness temperature data to invert the corresponding sea surface salinity.
In the above scheme, sea salinity is directly inverted through the acquired brightness temperature data, so that the salinity value obtained through inversion is greatly deviated from the actual salinity value, and the obtained sea salinity is inaccurate.
Disclosure of Invention
The present invention aims to provide a method, an apparatus, a device and a medium for obtaining sea surface salinity, so as to improve the accuracy of inverting sea surface salinity.
In order to achieve the above purpose, the technical solutions adopted in the embodiments of the present application are as follows:
in a first aspect, an embodiment of the present application provides a method for acquiring sea surface salinity, the method including:
acquiring brightness temperature data of a target sea area in a preset waveband through a microwave radiometer;
calculating the reflectivity of the target sea area in the preset wave band according to the brightness temperature data of the preset wave band;
correcting the reflectivity of the target sea area in the preset wave band according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity;
and performing salinity inversion according to the corrected reflectivity to obtain the sea surface salinity of the target sea area.
Specifically, the calculating the reflectivity of the target sea area in the preset waveband according to the brightness temperature data of the preset waveband includes:
determining the reflectivity of the target sea area in the preset waveband by adopting a pre-established radiation transfer model according to the brightness temperature data of the preset waveband, wherein the radiation transfer model comprises: and (3) corresponding relation between brightness temperature data and reflectivity.
Specifically, the step of correcting the reflectivity of the target sea area in the preset waveband according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity includes:
respectively calculating a plurality of groups of space-time weights of the target sea area by adopting a preset space-time weighting algorithm according to a plurality of groups of space-time information corresponding to the brightness temperature data;
and correcting the reflectivity of the target sea area in the preset wave band according to the plurality of groups of space-time weights to obtain the corrected reflectivity.
Specifically, the brightness and temperature data correspond to spatiotemporal information, which includes: the microwave radiometer acquires observation time of the bright temperature data, and a swing mode and a swing area when the microwave radiometer acquires the bright temperature data.
Specifically, the correcting the reflectivity of the target sea area in the preset waveband according to the multiple groups of space-time weights to obtain the corrected reflectivity includes:
processing by adopting a least square method according to the multiple groups of space-time weights to obtain a target weight; and correcting the reflectivity of the target sea area in the preset wave band according to the target weight to obtain the corrected reflectivity.
Specifically, the performing salinity inversion according to the corrected reflectivity to obtain sea surface salinity of the target sea area includes:
and according to the corrected reflectivity, performing salinity inversion by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
Specifically, the obtaining the sea surface salinity of the target sea area by performing salinity inversion according to the corrected reflectivity by using a nonlinear salinity inversion algorithm comprises:
according to the corrected reflectivity, performing salinity inversion by adopting a linear salinity inversion algorithm to obtain the initial sea surface salinity of the target sea area;
and processing the initial sea surface salinity of the target sea area by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
In a second aspect, an embodiment of the present application provides an apparatus for acquiring sea surface salinity, the apparatus comprising:
the acquisition module is used for acquiring brightness temperature data of a target sea area in a preset waveband through a microwave radiometer;
the calculation module is used for calculating the reflectivity of the target sea area in the preset wave band according to the brightness temperature data of the preset wave band;
the correction module is used for correcting the reflectivity of the target sea area in the preset wave band according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity;
and the inversion module is used for performing salinity inversion according to the corrected reflectivity to obtain the sea surface salinity of the target sea area.
Specifically, the calculation module is specifically configured to determine, according to the brightness temperature data of the preset waveband, a reflectivity of the target sea area at the preset waveband by using a pre-established radiation transfer model, where the radiation transfer model includes: and (3) corresponding relation between brightness temperature data and reflectivity.
Specifically, the correction module specifically includes:
the calculation submodule is used for calculating a plurality of groups of space-time weights of the target sea area respectively by adopting a preset space-time weighting algorithm according to a plurality of groups of space-time information corresponding to the brightness temperature data;
and the correction submodule is used for correcting the reflectivity of the target sea area in the preset wave band according to the multiple groups of space-time weights to obtain the corrected reflectivity.
Specifically, the correction submodule is specifically configured to perform processing by using a least square method according to the multiple groups of space-time weights to obtain a target weight; and correcting the reflectivity of the target sea area in the preset wave band according to the target weight to obtain the corrected reflectivity.
Specifically, the inversion module is specifically configured to perform salinity inversion by using a non-linear salinity inversion algorithm according to the corrected reflectivity, so as to obtain the sea surface salinity of the target sea area.
Specifically, the inversion module specifically includes:
the first inversion submodule is used for performing salinity inversion by adopting a linear salinity inversion algorithm according to the corrected reflectivity to obtain the initial sea surface salinity of the target sea area;
and the second inversion submodule is used for processing the initial sea surface salinity of the target sea area by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
In a third aspect, an embodiment of the present invention provides a computer device, which includes a memory and a processor, where the memory stores a computer program executable by the processor, and the processor implements the above-mentioned sea surface salinity obtaining method when executing the computer program.
In a fourth aspect, an embodiment of the present invention provides a storage medium, where a computer program is stored, and when the computer program is read and executed, the method for acquiring sea surface salinity is implemented.
The beneficial effect of this application is: the invention provides a sea surface salinity obtaining method, which comprises the steps of calculating brightness temperature data of a target sea area obtained by a microwave radiometer to obtain reflectivity of the corresponding target sea area, correcting the reflectivity of the target sea area according to time-space information of the brightness temperature data, and performing inversion on the corrected reflectivity to obtain the sea surface salinity of the target sea area. According to the scheme provided by the invention, the reflectivity of the target sea area can be corrected according to the time-space information of the brightness temperature data, and the inversion of the sea surface salinity is carried out through the corrected reflectivity, so that the inverted sea surface salinity precision is more accurate.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
Fig. 1 is a schematic flow chart of a sea surface salinity obtaining method according to an embodiment of the present application;
fig. 2 is a schematic flow chart of a sea surface salinity obtaining method according to an embodiment of the present application;
fig. 3 is a schematic flow chart of a sea surface salinity obtaining method according to an embodiment of the present application;
fig. 4 is a schematic structural diagram of a sea surface salinity obtaining device provided in an embodiment of the present application;
fig. 5 is a schematic structural diagram of a computer device according to an embodiment of the present application.
Detailed Description
In order to make the objects, 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 with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not intended to indicate or imply relative importance.
In order to realize the salinity inversion of the target sea area, the embodiments of the present invention provide the following possible implementation manners. Examples are explained below with reference to the drawings.
It should be noted that the sea salinity obtaining method provided by the present invention may be implemented by a computer device installed and operating with a sea salinity obtaining application, where the computer device may be a server or a client device, and the present invention is not limited thereto.
Fig. 1 is a schematic flow chart of a sea surface salinity obtaining method according to an embodiment of the present application; as shown in fig. 1, the method includes:
s1: and acquiring brightness temperature data of the target sea area in a preset waveband through a microwave radiometer.
Specifically, a microwave radiometer is a sensor that measures surface-radiated electromagnetic waves, receives only sea surface or atmospheric radiation, extracts physical information therefrom, and does not emit a probe electromagnetic wave. Microwave radiometers are actually high sensitivity, high resolution microwave receivers, i.e. only receiving microwaves radiated from the sea surface, but not transmitting microwaves. The microwave radiometer is mainly used for acquiring specific information such as sea surface temperature, sea surface wind speed, water vapor mass in the atmosphere, cloud liquid water content and the like. The sea surface microwave radiation is mainly determined by factors such as sea surface temperature, sea surface salinity, sea surface roughness condition and the like, and is influenced by factors such as radiation frequency, observation angle, polarization state and the like. The microwave radiometer commonly used at present may be mounted on a load, and is preferably a satellite, that is, the microwave radiometer may be a satellite-mounted microwave radiometer, which may be used to observe the brightness and temperature data of the target sea area in a preset waveband.
In the embodiment of the invention, the satellite-borne microwave radiometer can be a sea No. two A satellite microwave radiometer, for example.
The preset wave band is a designated wave band which needs to be observed on the target sea surface, for example, the preset wave band may be a C wave band, an X wave band, or other wave bands, which wave band needs to be observed specifically, and may be determined according to actual situations, which is not limited in the present application.
S2: and calculating the reflectivity of the target sea area in the preset wave band according to the brightness temperature data of the preset wave band.
Specifically, in the current research on marine atmospheric parameters, a one-to-one correspondence between sea surface light temperature data and reflectivity is created. The corresponding relation can be stored in a lookup table, and in the application process, the table lookup operation can be executed according to the brightness and temperature data of the preset waveband directly and the lookup table so as to obtain the reflectivity corresponding to the brightness and temperature data of the preset waveband, and the reflectivity corresponding to the brightness and temperature data of the preset waveband is determined as the reflectivity of the target sea area in the preset waveband.
S3: and correcting the reflectivity of the target sea area in a preset waveband according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity.
Specifically, the correspondence between the brightness temperature data and the reflectivity stored in the lookup table is actually a linear correspondence, so that a certain error exists in the reflectivity of the target sea area at the preset waveband obtained by searching, and a system error also exists in the microwave radiometer during observation, so that in the technical scheme of the application, the reflectivity of the target sea area at the preset waveband can be corrected.
In the embodiment of the application, when the microwave radiometer acquires the brightness temperature data of the target sea area at the preset waveband, the microwave radiometer may swing to some extent, so that the reflectivity of the preset waveband is corrected through the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity, and the corrected reflectivity can accurately reflect the reflectivity of the target sea area at the preset waveband when the brightness temperature data is acquired. The time-space information corresponding to the brightness temperature data may be, for example, time-space information when the microwave radiometer acquires the brightness temperature data.
S4: and performing salinity inversion according to the corrected reflectivity to obtain the sea surface salinity of the target sea area.
In the embodiment of the application, the sea surface salinity of the target sea area can be inverted according to the corrected reflectivity and the pre-established corresponding relation between the reflectivity and the sea surface salinity.
In summary, the embodiment of the present application provides a sea surface salinity obtaining method, where bright temperature data is obtained through a microwave radiometer, a table is looked up according to the bright temperature data to obtain a reflectivity of a corresponding target sea area preset waveband, the reflectivity of the target sea area preset waveband is corrected according to time-space information of the bright temperature data, and inversion is performed to obtain the sea surface salinity of the target sea area. The sea surface salinity of the target sea area is obtained by correcting the reflectivity of the preset wave band of the target sea area in time and space directions, so that the inversion result of the sea surface salinity is more accurate, and the inversion precision of the sea surface salinity is improved.
Further, S2 specifically includes: according to brightness temperature data of a preset waveband, determining the reflectivity of a target sea area in the preset waveband by adopting a pre-established radiation transfer model, wherein the radiation transfer model comprises the following steps: and (3) corresponding relation between brightness temperature data and reflectivity.
Specifically, the pre-established radiation delivery model can be expressed as the following formula (1):
TB＝TBU+τ[ETs+TBΩ]formula (1)
Wherein, TBBrightness temperature data, T, representing the target sea area at a predetermined bandBUIs the atmospheric interference temperature, TBΩIs the sea surface scattering of atmospheric radiation (sky radiation scattered upward by Earth surface), TSIs the sea surface temperature, τ is the atmospheric transmission (atmospherical transmission), and E is the sea surface emissivity (sea-surface emissivity). T isBΩThe specific expression forms in different parameterized radiation transfer models are different, but can be expressed by the following formula (2):
TBΩR.M equation (2)
Where R is the reflectivity corresponding to the sea surface emissivity, and it is generally considered approximately that the sum of the sea surface emissivity and the reflectivity is a constant, and R is 1-E. M is a function set containing atmospheric downlink radiation, atmospheric transmittance, sea surface scattering correction, and cosmic background radiation. According to equations (1) and (2), the sea surface reflectivity can be expressed by equation (3) as follows:
the radiation transfer model is pre-established with a corresponding relation between brightness temperature data and reflectivity, and brightness temperature data and related auxiliary data of a preset waveband are input into the radiation transfer model to obtain the reflectivity of a target sea area in the preset waveband. The associated auxiliary data may be, for example, at least one of atmospheric upward radiation, surface scattering of atmospheric radiation, surface temperature, atmospheric transmittance, surface emissivity.
On the basis of the sea surface salinity obtaining method shown in fig. 1, an embodiment of the present invention further provides a sea surface salinity obtaining method, fig. 2 shows a schematic flow chart of the sea surface salinity obtaining method according to the embodiment of the present invention, and as shown in fig. 2, the step S3 includes:
s31: and respectively calculating a plurality of groups of space-time weights of the target sea area by adopting a preset space-time weighting algorithm according to a plurality of groups of space-time information corresponding to the brightness temperature data.
Considering that the microwave radiometer has a certain swing when acquiring the brightness temperature data of the preset waveband of the target sea area, the brightness temperature data is subjected to space-time weighting processing through the space-time information corresponding to the brightness temperature data, specifically, a plurality of data points in a preset range around each observation point are selected for interpolation, for example, 100 points in a 10 × 10 range, and a group of space-time weights are calculated according to a group of space-time information corresponding to the observation points and the space-time information corresponding to the plurality of data points in the preset range.
In the embodiment of the application, the weight has a gaussian characteristic, and the weight decreases faster when the peak value is at the position closest to the observation point and the weight is farther from the observation point, so that the influence of the data points with farther distances on the weight is ensured to be smaller, and the data is prevented from being excessively smooth, therefore, a plurality of data points within a range of 10 x 10 (a mesoscale range) are selected to calculate by a least square method, and the marine phenomenon can be more accurately explained.
Each observation point may be any one of the brightness temperature data. Therefore, multiple groups of space-time weights can be obtained according to multiple groups of space-time information corresponding to the brightness temperature data.
For example, the following formula (4) can be used to calculate the observation point according to each observation point:
in the formula, xk,yk,tkIs the spatio-temporal information corresponding to each observation point, specifically, xk,ykIs the spatial information, t, corresponding to each observation pointkTime information corresponding to each observation point, wkIs a weight function, unIs the interpolated space-time weight, R and T are the size of the data window in space and time, respectively, JkThe weight for each observation point is calculated by using the following formula (5):
in the formula, the distance between two adjacent observation points corresponding to the space-time information is marked as 1, the distance between every two observation points is added with 1, and the distance is marked as D.
S32: and correcting the reflectivity of the target sea area in a preset wave band according to the plurality of groups of space-time weights to obtain the corrected reflectivity.
Specifically, the reflectivity of the target sea area in a preset waveband is corrected according to a weighting algorithm to obtain the corrected reflectivity.
According to the embodiment of the application, the reflectivity is weighted in the space-time direction, so that the reflectivity is not a simple value obtained based on a linear model any more, but the space-time information when the brightness temperature data is obtained is combined, the obtained reflectivity is more accurate, and the salinity inversion precision is improved.
Further, the above brightness temperature data corresponding to the time-space information includes: the method comprises the following steps of observing the brightness temperature data acquired by the microwave radiometer, and obtaining the swing mode and the swing area of the brightness temperature data acquired by the microwave radiometer.
Specifically, the time information corresponding to the brightness temperature data is observation time of the brightness temperature data acquired by the microwave radiometer, and the spatial information is a swing direction and a swing area when the brightness temperature data is acquired by the microwave radiometer. When the microwave radiometer acquires the brightness temperature data, the microwave radiometer is propelled at a constant speed in the advancing direction, and swings in the observation mode which is orthogonal to the advancing direction and the direction vertical to the ground, so that the swinging mode and the swinging area of the microwave radiometer when the brightness temperature data is acquired need to be considered, and the time information when the brightness temperature data is acquired is combined, so that the space-time weight of the reflectivity is adjusted.
In the embodiment of the application, the reflectivity is corrected by utilizing the space-time weight taking time and space as weight factors, so that the corrected reflectivity has higher accuracy.
Further, S32 includes: processing by adopting a least square method according to a plurality of groups of space-time weights to obtain a target weight; and correcting the reflectivity of the target sea area in a preset wave band according to the target weight to obtain the corrected reflectivity.
Specifically, when the brightness temperature data is subjected to space-time weighting processing, a plurality of data points in a preset range around each observation point are selected, for example, 100 points in a range of 10 × 10 around the observation point are selected, a space-time weight value of the data points is calculated, the space-time information of the plurality of data points needs to be fitted by a least square method, a target weight value of the brightness temperature data is obtained, and the reflectivity is weighted according to the target weight value, so that the corrected reflectivity is obtained.
In the embodiment of the application, the space-time information of the data points around the observation point is fitted by a least square method, and the obtained target weight value is more accurate than the result obtained by directly carrying out average value calculation on the space-time information of the data points around the observation point, so that the corrected reflectivity is more accurate, and the salinity inversion precision is improved.
Further, S4 includes: and according to the corrected reflectivity, performing salinity inversion by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
The non-linear salinity inversion algorithm shown above may be: newton's algorithm or, Nelder-Mead algorithm.
In the embodiment of the application, the newton algorithm is to continuously perform step-length-variable iteration on the calculation result, and when the iteration reaches an approximate minimum value meeting the precision, the iteration is stopped. The Nelder-Mead algorithm is to search for local minima by cycling continuously, and stop cycling if the error is less than a preset error threshold. Which algorithm is specifically adopted is determined according to actual conditions, and the method is not limited in the application.
In the selection process of the algorithm, the calculation results of the multiple nonlinear salinity inversion algorithms are compared, and one or two algorithms with the calculation results superior to those of other nonlinear salinity inversion algorithms are selected, for example, in the embodiment of the application, the Newton algorithm or the Nelder-Mead algorithm is selected to have a better salinity inversion effect.
In order to make the accuracy of the salinity inversion result higher, the selected algorithm needs to be optimized, for example, in the embodiment of the application, the calculation accuracy of the newton algorithm and the Nelder-Mead algorithm is performed, the results of the newton algorithm and the Nelder-Mead algorithm are compared, and if the difference between the results of the newton algorithm and the Nelder-Mead algorithm is within 1%, the sea surface salinity value obtained by inversion of the two algorithms is considered to be more reliable.
According to the embodiment of the application, the sea surface salinity is calculated by adopting a nonlinear salinity inversion algorithm, and the precision reaches the requirement or the error is smaller than the preset error threshold value through continuous calculation, so that the precision of the obtained sea surface salinity is higher.
Further, an embodiment of the present application further provides a method for obtaining sea surface salinity, fig. 3 shows a schematic flow chart of the method for obtaining sea surface salinity of the embodiment of the present application, and as shown in fig. 3, the obtaining sea surface salinity of the target sea area by performing salinity inversion by using a non-linear salinity inversion algorithm according to the corrected reflectivity includes:
s321: and according to the corrected reflectivity, performing salinity inversion by adopting a linear salinity inversion algorithm to obtain the initial sea surface salinity of the target sea area.
Specifically, the linear salinity inversion algorithm may be a linear relationship between a reflectivity and sea surface salinity established in advance, and the salinity inversion is performed by the linear salinity inversion algorithm, so as to obtain an initial sea surface salinity of the target sea area.
S322: and processing the initial sea surface salinity of the target sea area by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
Specifically, since the initial sea salinity is obtained by a linear salinity inversion algorithm, and the accuracy of the linear salinity inversion algorithm may be poor because relevant factors are not considered, the initial sea salinity and the reflectivity need to be sent to a non-linear salinity inversion algorithm, that is, a newton algorithm and a Nelder-Mead algorithm, and the sea salinity is calculated by the two algorithms, and the specific calculation steps are as above and are not described again.
According to the embodiment of the application, the initial sea salinity is obtained through the existing linear salinity inversion algorithm, and then the initial sea salinity and the reflectivity are calculated through the nonlinear salinity inversion algorithm to obtain the sea salinity of the target sea area. The sea surface salinity obtained by the linear salinity inversion algorithm and the non-linear salinity inversion algorithm in the embodiment of the application has higher precision.
The following describes apparatuses, devices, storage media, and the like for implementing the sea surface salinity obtaining method provided by the present application, and specific implementation processes and technical effects thereof are referred to above, and will not be described again below.
Fig. 4 is a schematic structural diagram of a sea surface salinity obtaining apparatus provided in an embodiment of the present application, and as shown in fig. 4, the sea surface salinity obtaining apparatus includes:
the acquisition module 100 is configured to acquire brightness and temperature data of a target sea area in a preset waveband through a microwave radiometer;
the calculating module 200 is configured to calculate a reflectivity of the target sea area in the preset waveband according to the brightness and temperature data of the preset waveband;
the correcting module 300 is configured to correct the reflectivity of the target sea area in the preset waveband according to the time-space information corresponding to the brightness temperature data, so as to obtain a corrected reflectivity;
and the inversion module 400 is used for performing salinity inversion according to the corrected reflectivity to obtain the sea surface salinity of the target sea area.
Specifically, the calculating module 200 is specifically configured to determine, according to the brightness temperature data of the preset waveband, a reflectivity of the target sea area in the preset waveband by using a pre-established radiation transfer model, where the radiation transfer model includes: and (3) corresponding relation between brightness temperature data and reflectivity.
Specifically, the calibration module 300 specifically includes:
the calculation submodule is used for calculating a plurality of groups of space-time weights of the target sea area respectively by adopting a preset space-time weighting algorithm according to a plurality of groups of space-time information corresponding to the brightness temperature data;
and the correction submodule is used for correcting the reflectivity of the target sea area in the preset wave band according to the plurality of groups of space-time weights to obtain the corrected reflectivity.
Specifically, the correction submodule is specifically configured to perform processing by using a least square method according to the multiple groups of space-time weights to obtain a target weight; and correcting the reflectivity of the target sea area in the preset wave band according to the target weight to obtain the corrected reflectivity.
Specifically, the inversion module 400 is specifically configured to perform salinity inversion by using a non-linear salinity inversion algorithm according to the corrected reflectivity, so as to obtain the sea surface salinity of the target sea area.
Specifically, the inversion module 400 is specifically configured to perform salinity inversion by using a linear salinity inversion algorithm according to the corrected reflectivity, so as to obtain an initial sea surface salinity of the target sea area; and processing the initial sea surface salinity of the target sea area by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
The sea surface salinity acquiring device is used for executing the sea surface salinity acquiring method provided by the foregoing embodiment, and the implementation principle and the technical effect are similar, and are not described herein again.
These above modules may be one or more integrated circuits configured to implement the above methods, such as: one or more Application Specific Integrated Circuits (ASICs), or one or more microprocessors (DSPs), or one or more Field Programmable Gate Arrays (FPGAs), among others. For another example, when one of the above modules is implemented in the form of a Processing element scheduler code, the Processing element may be a general-purpose processor, such as a Central Processing Unit (CPU) or other processor capable of calling program code. For another example, these modules may be integrated together and implemented in the form of a system-on-a-chip (SOC).
Fig. 5 is a schematic diagram of a computer device provided in an embodiment of the present application, where the computer device may be integrated in a terminal device or a chip of the terminal device, and the terminal may be a computing device with a data processing function.
The computer device 500 includes: a processor 501 and a memory 502.
The memory 502 is used for storing programs, and the processor 501 calls the programs stored in the memory 502 to execute the above-mentioned method embodiments. The specific implementation and technical effects are similar, and are not described herein again.
Optionally, the invention also provides a program product, for example a computer-readable storage medium, comprising a program which, when being executed by a processor, is adapted to carry out the above-mentioned method embodiments.
In the embodiments provided in the present invention, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.
The integrated unit implemented in the form of a software functional unit may be stored in a computer readable storage medium. The software functional unit is stored in a storage medium and includes several instructions to enable a computer device (which may be a personal computer, a server, or a network device) or a processor (processor) to execute some steps of the methods according to the embodiments of the present invention. And the aforementioned storage medium includes: a U disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and shall be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (9)
1. A method of sea surface salinity estimation, comprising:
acquiring brightness temperature data of a target sea area in a preset waveband through a microwave radiometer;
calculating the reflectivity of the target sea area in the preset wave band according to the brightness temperature data of the preset wave band;
correcting the reflectivity of the target sea area in the preset wave band according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity, wherein the time-space information is time information and space information when the microwave radiometer acquires the brightness temperature data;
performing salinity inversion according to the corrected reflectivity to obtain sea surface salinity of the target sea area;
the correcting the reflectivity of the target sea area in the preset wave band according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity comprises the following steps:
according to multiple groups of space-time information corresponding to the brightness temperature data, adopting a preset space-time weighting algorithm to respectively calculate multiple groups of space-time weights of the target sea area, wherein each group of space-time information is space-time information of a plurality of observation points in a preset range of one brightness temperature data corresponding to the observation point in a preset wave band, and a calculation formula of each group of space-time weights is as follows:
wherein, the value of N is the number of observation points, the value of N is the group number of the space-time information, and wkIs a weight function of each observation point, JkFor each observation point a distance weight, wkAnd JkThe calculation formulas of (A) and (B) are respectively as follows:
xk,ykis the spatial information, t, corresponding to each observation pointkTime information for each observation point, R and T being the size of the data window in space and time, respectively, DkThe distance between each observation point and a standard observation point in a preset range is calculated;
and correcting the reflectivity of the target sea area in the preset wave band according to the plurality of groups of space-time weights to obtain the corrected reflectivity.
2. The method of claim 1, wherein the calculating the reflectivity of the target sea area in the preset waveband according to the brightness temperature data of the preset waveband comprises:
and determining the reflectivity of the target sea area in the preset waveband by adopting a pre-established corresponding relation between the brightness temperature data and the reflectivity according to the brightness temperature data of the preset waveband.
3. The method of claim 1, wherein the brightness temperature data corresponds to spatiotemporal information comprising: the microwave radiometer acquires observation time of the bright temperature data, and a swing mode and a swing area when the microwave radiometer acquires the bright temperature data.
4. The method according to claim 1, wherein the correcting the reflectivity of the target sea area in the preset wavelength band according to the plurality of sets of space-time weights to obtain a corrected reflectivity comprises:
processing by adopting a least square method according to the multiple groups of space-time weights to obtain a target weight; and correcting the reflectivity of the target sea area in the preset wave band according to the target weight to obtain the corrected reflectivity.
5. The method of claim 1, wherein said performing salinity inversion based on said corrected reflectivities to obtain sea surface salinity of said target sea area comprises:
and according to the corrected reflectivity, performing salinity inversion by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
6. The method of claim 5, wherein said performing salinity inversion using a non-linear salinity inversion algorithm based on said corrected reflectivity to obtain sea surface salinity of said target sea area comprises:
according to the corrected reflectivity, performing salinity inversion by adopting a linear salinity inversion algorithm to obtain the initial sea surface salinity of the target sea area;
and processing the initial sea surface salinity of the target sea area by adopting a nonlinear salinity inversion algorithm to obtain the sea surface salinity of the target sea area.
7. A sea surface salinity harvesting apparatus, comprising:
the acquisition module is used for acquiring brightness temperature data of a target sea area in a preset waveband through a microwave radiometer;
the calculation module is used for calculating the reflectivity of the target sea area in the preset wave band according to the brightness temperature data of the preset wave band;
the correction module is used for correcting the reflectivity of the target sea area in the preset waveband according to the time-space information corresponding to the brightness temperature data to obtain the corrected reflectivity, wherein the time-space information is time information and space information when the microwave radiometer acquires the brightness temperature data;
the inversion module is used for performing salinity inversion according to the corrected reflectivity to obtain the sea surface salinity of the target sea area;
the correction module includes:
the calculation submodule is used for calculating a plurality of groups of space-time weights of the target sea area respectively by adopting a preset space-time weighting algorithm according to a plurality of groups of space-time information corresponding to the brightness temperature data, wherein each group of space-time information is space-time information of a plurality of observation points in a preset range of one brightness temperature data corresponding to the observation point in a preset wave band, and a calculation formula of each group of space-time weights is as follows:
wherein, the value of N is the number of observation points, the value of N is the group number of the space-time information, and wkIs a weight function of each observation point, JkFor each observation point a distance weight, wkAnd JkThe calculation formulas of (A) and (B) are respectively as follows:
xk,ykis the spatial information, t, corresponding to each observation pointkTime information for each observation point, R and T being the size of the data window in space and time, respectively, DkThe distance between each observation point and a standard observation point in a preset range is calculated;
and the correction submodule is used for correcting the reflectivity of the target sea area in the preset wave band according to the multiple groups of space-time weights to obtain the corrected reflectivity.
8. A computer apparatus comprising a memory and a processor, the memory storing a computer program executable by the processor, the processor implementing the method of sea surface salinity estimation of any preceding claim 1 to 6 when executing the computer program.
9. A storage medium having stored thereon a computer program which, when read and executed, implements the sea surface salinity estimation method of any of claims 1-6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011413746.7A CN112414554B (en) | 2020-12-02 | 2020-12-02 | Sea surface salinity obtaining method, device, equipment and medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011413746.7A CN112414554B (en) | 2020-12-02 | 2020-12-02 | Sea surface salinity obtaining method, device, equipment and medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112414554A CN112414554A (en) | 2021-02-26 |
| CN112414554B true CN112414554B (en) | 2021-12-07 |
Family
ID=74774929
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011413746.7A Expired - Fee Related CN112414554B (en) | 2020-12-02 | 2020-12-02 | Sea surface salinity obtaining method, device, equipment and medium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112414554B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114088593B (en) * | 2021-10-11 | 2022-10-11 | 中科三清科技有限公司 | Method and device for determining sea salt discharge flux |
| CN114037023B (en) * | 2021-12-20 | 2024-05-10 | 中国石油大学(华东) | Correction method for correcting polar region abnormal water vapor data of microwave radiometer by using ocean satellite |
| CN114758080A (en) * | 2022-06-14 | 2022-07-15 | 中国科学院空天信息创新研究院 | Sea surface salinity gridding inversion method and device |
| CN114756805B (en) * | 2022-06-14 | 2022-10-28 | 中国科学院空天信息创新研究院 | Sea surface emissivity correction method and device |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1279970A2 (en) * | 2001-05-31 | 2003-01-29 | Starlab Barcelona SL | A system for monitoring a feature of a surface with broad swath and high resolution |
| CN102642947A (en) * | 2012-04-23 | 2012-08-22 | 西安交通大学 | Supercritical water oxidization treatment system for high-salinity organic waste water |
| CN105606631A (en) * | 2016-02-01 | 2016-05-25 | 中国科学院遥感与数字地球研究所 | Method for jointly inversing soil moisture through salinity satellite dual-waveband brightness temperature data |
| CN105737806A (en) * | 2016-02-16 | 2016-07-06 | 国家卫星海洋应用中心 | Method and device for inverting sea surface salinity based on satellite-borne microwave radiometer |
| CN105760699A (en) * | 2016-03-18 | 2016-07-13 | 中国科学院国家空间科学中心 | Sea surface salinity retrieval method and device |
| CN105808874A (en) * | 2016-03-18 | 2016-07-27 | 中国科学院国家空间科学中心 | Method and apparatus for establishing atmospheric top layer microwave transmission model function |
| CN109725316A (en) * | 2018-12-18 | 2019-05-07 | 中国人民解放军国防科技大学 | One-dimensional synthetic aperture microwave radiometer-based sea surface temperature physical inversion method |
| CN110543835A (en) * | 2019-08-15 | 2019-12-06 | 青岛大学 | Satellite sea surface salinity remote sensing product precision evaluation method based on triple matching theory |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| MX2011010713A (en) * | 2011-10-11 | 2012-01-27 | Sadot Bermejo Lajud | Process for treating congenital water. |
| CN107870043A (en) * | 2017-10-25 | 2018-04-03 | 中国科学院国家空间科学中心 | A kind of extra large table parameter synchronization inverting optimization method |
| CN110909491A (en) * | 2019-12-11 | 2020-03-24 | 新亚优华科技有限公司 | Sea surface salinity inversion algorithm based on wind and cloud meteorological satellite |
-
2020
- 2020-12-02 CN CN202011413746.7A patent/CN112414554B/en not_active Expired - Fee Related
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1279970A2 (en) * | 2001-05-31 | 2003-01-29 | Starlab Barcelona SL | A system for monitoring a feature of a surface with broad swath and high resolution |
| CN102642947A (en) * | 2012-04-23 | 2012-08-22 | 西安交通大学 | Supercritical water oxidization treatment system for high-salinity organic waste water |
| CN105606631A (en) * | 2016-02-01 | 2016-05-25 | 中国科学院遥感与数字地球研究所 | Method for jointly inversing soil moisture through salinity satellite dual-waveband brightness temperature data |
| CN105737806A (en) * | 2016-02-16 | 2016-07-06 | 国家卫星海洋应用中心 | Method and device for inverting sea surface salinity based on satellite-borne microwave radiometer |
| CN105760699A (en) * | 2016-03-18 | 2016-07-13 | 中国科学院国家空间科学中心 | Sea surface salinity retrieval method and device |
| CN105808874A (en) * | 2016-03-18 | 2016-07-27 | 中国科学院国家空间科学中心 | Method and apparatus for establishing atmospheric top layer microwave transmission model function |
| CN109725316A (en) * | 2018-12-18 | 2019-05-07 | 中国人民解放军国防科技大学 | One-dimensional synthetic aperture microwave radiometer-based sea surface temperature physical inversion method |
| CN110543835A (en) * | 2019-08-15 | 2019-12-06 | 青岛大学 | Satellite sea surface salinity remote sensing product precision evaluation method based on triple matching theory |
Non-Patent Citations (3)
| Title |
|---|
| Aquarius: An instrument to monitor sea surface salinity from space;David M. Le Vine等;《IEEE Transaction on Geoscience and Remote Sensing》;20070731;第45卷(第7（2007）期);第2040-2049页 * |
| 星载微波辐射计的线性与非线性反演算法比较;王兆徽 等;《航天器工程》;20150831;第24卷(第4（2015）期);第130-135页 * |
| 海面盐度多源遥感协同反演方法研究;周博天;《中国博士学位论文全文数据库 基础科学辑》;20131015(第10（2013）期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112414554A (en) | 2021-02-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112414554B (en) | Sea surface salinity obtaining method, device, equipment and medium | |
| Haddad et al. | The TRMM ‘day-1’radar/radiometer combined rain-profiling algorithm | |
| CN112965146A (en) | Quantitative precipitation estimation method combining meteorological radar and rainfall barrel observation data | |
| CN109100723A (en) | Upper-level winds inversion method based on Doppler radar data | |
| Yang et al. | Preliminary validation of ocean surface vector winds estimated from China’s HY-2A scatterometer | |
| CN111103572B (en) | Satellite-borne SAR polarization calibration method and device based on distribution targets | |
| CN113075660A (en) | Method and device for inverting sea surface wind wave parameters based on SAR (synthetic aperture radar) | |
| CN114384518A (en) | Sea surface SAR image simulation method and device based on Ku waveband actual measurement data | |
| Yu et al. | Resolution enhancement technique using range oversampling | |
| Guo et al. | Evaluation of terrain effect on microwave radiometer measurement and its correction | |
| CN115840192B (en) | Indoor positioning method based on space estimation spectrum confidence estimation | |
| Cayula et al. | VIIRS-derived SST at the Naval Oceanographic Office: From evaluation to operation | |
| CN110866942B (en) | On-orbit radiation response tracking method and system for multi-source target fusion | |
| Belcher et al. | Ionospheric effects on synthetic aperture radar (SAR) clutter statistics | |
| Torres et al. | The impact of signal processing on the range-weighting function for weather radars | |
| CN113687321B (en) | Radar target detection distance evaluation method and device | |
| US11971309B2 (en) | Measurement data processing device | |
| CN105974413B (en) | The self-focusing method of more base external illuminators-based radar imaging systems | |
| CN112819729B (en) | Image correction method and device, computer storage medium and equipment | |
| CN113125015B (en) | Long-time sequence tracking method and system for satellite sensor | |
| Wang et al. | Improved CycleGAN-based shadow estimation for ocean wave height inversion from marine X-band radar images | |
| Cucurull et al. | An improved one-dimensional bending angle forward operator for the assimilation of radio occultation profiles in the lower troposphere | |
| CN113670953B (en) | Method for solving SNR interference peak of direct and reflected signals based on weighting window | |
| Morris et al. | A coupled-pixel model (CPM) atmospheric retrieval algorithm for high-resolution imagers | |
| US10215835B1 (en) | Estimating location of source of signal of interest |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20211207 |