Space-borne lidar and reanalysis data multi-wavelength atmospheric transmittance retrieval method

Abstract

The application provides a spaceborne lidar and reanalysis data multi-wavelength atmospheric transmittance retrieval method, and relates to the field of atmospheric remote sensing. The retrieval method is based on spaceborne lidar data and reanalysis data, and combines wavelength conversion and data fusion to accurately calculate the atmospheric transmittance at different wavelengths. The method comprises the following implementation steps: step 1, selecting spaceborne lidar data; step 2, screening the extinction coefficient; step 3, generating a spatiotemporal matching data set; step 4, establishing an aerosol extinction-transmittance conversion model; step 5, calculating the atmospheric molecular and ozone transmittance; step 6, layer transmittance fusion; and step 7, calculating the whole-layer atmospheric transmittance.

Description

TECHNICAL FIELD

[0001] The application provides a multi-wavelength atmospheric transmittance inversion method based on a spaceborne lidar and reanalysis data cooperation, and relates to the field of atmospheric remote sensing. BACKGROUND

[0002] As a core technology of modern remote sensing, spaceborne lidar has been widely used in global cloud-aerosol vertical distribution detection, carbon cycle monitoring, three-dimensional wind field inversion and other fields by emitting high-precision laser pulses from a satellite platform and receiving atmospheric backscattering signals. However, the laser signal will be attenuated by the atmospheric transmittance during transmission, resulting in signal strength attenuation with transmission distance.

[0003] Based on the reality that the global atmospheric transmittance is not uniform, it is necessary to accurately evaluate the global atmospheric transmittance to enhance the reliability of the detection data. At present, the method of atmospheric transmittance inversion mainly relies on empirical models or single sounding data, and such inversion method is difficult to accurately invert the real-time global atmospheric transmittance. Although the reanalysis data can provide global coverage of temperature, pressure and other meteorological parameters, the vertical resolution of the reanalysis data is seriously mismatched with the spaceborne lidar observation, so the fusion of spaceborne lidar and reanalysis data is seriously restricted.

[0004] In view of the above prior art, it is urgent to develop a new transmittance inversion method that can cooperatively utilize the advantages of spaceborne lidar and reanalysis data to solve the core technical problems such as multi-source data fusion matching.

[0005] Therefore, the present application is proposed. SUMMARY

[0006] The spaceborne lidar and reanalysis data multi-wavelength atmospheric transmittance inversion method described in the application aims to solve the problems existing in the prior art and proposes an inversion method based on spaceborne lidar and reanalysis data cooperation, in order to solve the deficiency of real atmospheric scene in the spaceborne lidar simulation process, and to provide a multi-source data fusion solution.

[0007] To achieve the above design purpose, the spaceborne lidar and reanalysis data multi-wavelength atmospheric transmittance inversion method is based on spaceborne lidar data and reanalysis data, and combines wavelength conversion and data fusion to accurately calculate the atmospheric transmittance at different wavelengths; including the following implementation steps:

[0008] Step 1), selecting spaceborne lidar data;

[0009] Download aerosol profile data and vertical feature data, including but not limited to cloud-aerosol discrimination score, extinction QC flag, extinction uncertainty data, aerosol layer classification and aerosol extinction coefficient;

[0010] Step 2), screening extinction coefficient;

[0011] Step 3), generating a spatiotemporal matching dataset;

[0012] Obtain the aerosol extinction coefficient and classification data in the spaceborne lidar data, and the temperature, pressure, and ozone mixing ratio data in the reanalysis data, and use a spatiotemporal sliding window matching algorithm to align the lidar data and the reanalysis data according to the spatiotemporal resolution to generate a collaborative dataset;

[0013] Step 4), establishing an aerosol extinction-transmittance conversion model;

[0014] Based on the aerosol classification data, dynamically select the wavelength conversion parameters to establish an aerosol extinction-transmittance conversion model;

[0015] Step 5), calculating the atmospheric molecule and ozone transmittance;

[0016] Combine the reanalysis data to calculate the atmospheric molecule and ozone transmittance by the atmospheric molecule scattering theory and the ozone absorption spectrum;

[0017] Step 6), layered transmittance fusion;

[0018] Use the pressure layer interpolation method to unify the atmospheric molecule, ozone, and aerosol transmittance to the same height coordinate system;

[0019] Step 7), whole-layer atmospheric transmittance calculation;

[0020] Multiply the atmospheric molecule, ozone, and aerosol transmittance at the same height obtained in step 6) to obtain the transmittance of each layer; multiply the transmittance of each layer to obtain the whole-layer atmospheric transmittance

[0021] Further, the step 2) pre-processes the spaceborne lidar data obtained in step 1), including but not limited to screening effective extinction coefficient data based on cloud-aerosol discrimination score, removing data according to extinction QC flag, excluding data points with uncertainty exceeding threshold, zeroing the extinction coefficient of the area identified as clean atmosphere, removing aerosol data disturbed by high-altitude ice clouds, and limiting the reasonable value range of the extinction coefficient.

[0022] Further, the step 3) resamples the spaceborne lidar data according to the global gridded resolution of the reanalysis data, retains the data within the range of the lidar transit track, and generates a spatial matching dataset;

[0023] The reanalysis data is time-matched based on the acquisition time of the measured aerosol extinction coefficient of the spaceborne lidar; if the reanalysis data used is daily average data, the time nearest neighbor interpolation method is used to match the precise acquisition time of the lidar; if the reanalysis data used is monthly average data, all lidar transit data for the current month are matched with the reanalysis dataset for that month; thus, a collaborative dataset is obtained.

[0024] Further, in step 4), the aerosols of the spaceborne lidar are classified. The extinction coefficient of non-spherical aerosols is calculated using a T-matrix, while the extinction coefficient of spherical aerosols is calculated using Mie scattering, to obtain... index;

[0025] according to Calculate the aerosol extinction coefficient at the target wavelength, where σ(λ2) is the extinction coefficient at the converted target wavelength, and σ(λ1) is the extinction coefficient at the wavelength of the spaceborne lidar. for index;

[0026] according to The aerosol optical thickness was calculated and compared with the actual measurement site of AERONET, and then based on... Calculate the aerosol transmittance at the target wavelength; where Z C Z represents ground height. sat This represents the highest altitude reached by satellite exploration.

[0027] Furthermore, in step 5), only Rayleigh scattering is considered when calculating atmospheric molecular scattering, and the atmospheric molecular extinction coefficient is calculated according to the following formula:

[0028]

[0029] Where, N A =6.02214×10 23 (1 / mol) is Avogadro's constant, R a = 8.314472 (J / K / mol) is the molar gas constant, P(Z) is the gas pressure, and T(Z) is the temperature; Q s (λ) is the total Rayleigh scattering cross section caused by each atmospheric molecule in "standard air", calculated as follows:

[0030]

[0031] The transmittance of atmospheric molecules is shown below:

[0032]

[0033] When calculating the ozone extinction coefficient, the atmospheric density must first be calculated:

[0034]

[0035] Where ρ(Z) is the atmospheric density, R is the gas constant (287.058 J / (kg·K)), P(Z) and T(Z) are the air pressure and temperature, respectively. The ozone mass mixing ratio is converted into column density per kilometer:

[0036]

[0037] Where, r o (Z) represents the ozone mixing ratio obtained from ERA5;

[0038] The ozone transmittance is calculated as follows:

[0039]

[0040] Among them, c o This is the ozone absorption coefficient.

[0041] Further, in step 6), based on the extinction coefficients of atmospheric molecules and ozone calculated in step 5), a hierarchical adaptive interpolation method is used for height matching based on the vertical resolution in the spaceborne lidar data, and then the transmittance of atmospheric molecules and ozone is calculated.

[0042] High-precision matching is achieved using a nonlinear interpolation algorithm in the dense aerosol layer, where the extinction coefficient threshold is >0.01km. -1 Determination: Efficient matching is performed using a linear interpolation algorithm within a clean atmosphere, where the clean atmosphere is defined as having an extinction coefficient threshold of ≤0.001km. -1 Judgment: The extinction coefficient of the transition layer is between 0.001 and 0.01 km. -1 The matching is performed using a weighted combination of the nonlinear interpolation algorithm and the linear interpolation algorithm.

[0043] Furthermore, in step 7), the transmittance of each component is fused using an algorithm to obtain the transmittance of the entire atmospheric layer;

[0044] The combined transmittance T at each vertical height is expressed as: T = T α ·T m ·T o ;

[0045] Total atmospheric transmittance T A The calculation formula is: T A =T1·T2·····T n Where n is the total number of layers in the vertical direction.

[0046] In summary, the advantages and beneficial effects of the spaceborne lidar and reanalysis data multi-wavelength atmospheric transmittance inversion method proposed in this application are as follows:

[0047] By leveraging the global coverage advantage of high-resolution observation data and reanalysis data from spaceborne lidar, this application proposes a multi-source data spatiotemporal matching algorithm and a hierarchical adaptive interpolation method, thereby achieving high-precision inversion of aerosol, atmospheric molecule, and ozone transmittance.

[0048] This application effectively addresses issues such as vertical resolution mismatch and aerosol-cloud interaction analysis in existing technologies through dynamic wavelength parameter selection and hierarchical fusion techniques, providing more reliable data support. Simultaneously, it proposes a method for accurately calculating atmospheric transmittance at different wavelengths, offering technical support for spaceborne lidar simulation and data quality improvement. Attached Figure Description

[0049] Figure 1 This is a flowchart of the multi-wavelength atmospheric transmittance inversion method for spaceborne lidar and reanalysis data described in this application;

[0050] Figure 2 This is a schematic diagram of the extinction coefficients at various wavelengths after wavelength conversion of the 532nm aerosol profile using the method described in this application;

[0051] Figure 3 This is a comparison chart of the aerosol optical thickness calculated using this application and the aerosol optical thickness measured at the site.

[0052] Figure 4-1 and Figure 4-2 These are schematic diagrams of the matched atmospheric molecules and ozone extinction coefficient profiles. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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.

[0054] Example 1, as Figure 1 As shown in Figure 4, a method for inverting atmospheric transmittance at different wavelengths using spaceborne lidar and reanalysis data is based on spaceborne lidar data and reanalysis data, and combines wavelength conversion and data fusion to accurately calculate atmospheric transmittance at different wavelengths.

[0055] Atmospheric transmittance refers to the effective proportion of light transmitted through the atmosphere from a source point to a target point. When light passes through the Earth's atmosphere, it is affected by scattering and absorption by atmospheric molecules, aerosols, and ozone, leading to signal attenuation. Atmospheric transmittance is of great significance for fields such as astronomical observation, remote sensing, and laser communication.

[0056] Aerosols are gaseous dispersion systems composed of solid or liquid particles suspended in a gaseous medium.

[0057] The extinction coefficient refers to the relative attenuation rate of electromagnetic radiation per unit distance propagated in the atmosphere.

[0058] Aerosol optical thickness refers to the optical thickness caused by the absorption and scattering of solar radiation by aerosols in the atmosphere. Aerosol optical thickness is the integral of the aerosol extinction coefficient in the vertical direction and is an important parameter describing the degree of aerosol pollution, used to measure the attenuation of solar radiation by aerosol particles in a vertical atmospheric column. The specific calculation formula is as follows:

[0059]

[0060] In the formula, τ a (λ) represents the aerosol optical thickness at wavelength λ, α a (λ,z) ​​represents the aerosol extinction coefficient at the height of the wavelength;

[0061] Atmospheric pressure refers to the atmospheric pressure acting on a unit area, which is numerically equal to the weight of a vertical column of air extending upwards to the upper boundary of the atmosphere per unit area.

[0062] Temperature refers to the thermal state of a substance and is usually used to describe the level of heat in an object.

[0063] A profile is a curve that shows how a certain parameter of the atmosphere or Earth's surface changes with altitude or distance.

[0064] The ozone mass mixing ratio refers to the mass of ozone per unit volume.

[0065] The method for inverting atmospheric transmittance using spaceborne lidar and reanalysis data with multi-wavelength atmospheric transmittance includes the following implementation steps:

[0066] Step 1) Select spaceborne lidar data;

[0067] Download aerosol profile data and vertical feature data, including but not limited to cloud-aerosol discrimination scores, extinction QC marks, extinction uncertainty data, aerosol layer classification and aerosol extinction coefficient;

[0068] Step 2) Screening the extinction coefficients;

[0069] Preprocess the spaceborne lidar data obtained in step 1), including but not limited to screening effective extinction coefficient data based on cloud-aerosol discrimination scores and selecting extinction coefficient data with cloud-aerosol discrimination scores between -100 and -20.

[0070] Based on the extinction QC mark, low-confidence data were eliminated, and extinction coefficient data with extinction QC mark elimination of 0, 1, 16, and 18 were selected;

[0071] Data points with uncertainty exceeding the threshold were excluded, and extinction uncertainty of 99.9 km was removed. -1 Extinction coefficient data;

[0072] The extinction coefficient of areas marked as "clean air" is set to zero; the extinction coefficient of areas marked as "clean air" by the vertical feature layer is set to 0.0 km. -1 ;

[0073] Remove aerosol data that is interfered with by high-altitude ice clouds and delete independent aerosols near ice clouds above 4km.

[0074] To limit the reasonable range of extinction coefficient values, select an extinction coefficient between 0 and 1.25 km. -1 Data between;

[0075] Step 3) Generate a spatiotemporal matching dataset;

[0076] We acquire aerosol extinction coefficient and classification data from spaceborne lidar data, as well as temperature / pressure / ozone mixing ratio data from reanalysis data. We then use a spatiotemporal sliding window matching algorithm to align lidar data and reanalysis data according to spatiotemporal resolution to generate a collaborative dataset.

[0077] Specifically, the spaceborne lidar data is resampled according to the global grid resolution of the reanalysis data, retaining the data within the lidar's transit trajectory range, and generating a spatial matching dataset;

[0078] The reanalysis data is time-matched based on the acquisition time of the measured aerosol extinction coefficient of the spaceborne lidar. If the reanalysis data used is daily average data, the time nearest neighbor interpolation method is used to match the precise acquisition time of the lidar. If the reanalysis data used is monthly average data, all lidar transit data for the current month are matched with the reanalysis dataset for that month.

[0079] Obtain the collaborative dataset;

[0080] Step 4) Establish an aerosol extinction-transmittance conversion model;

[0081] Based on aerosol classification data, wavelength conversion parameters are dynamically selected to establish an aerosol extinction-transmittance conversion model.

[0082] The aerosol extinction-transmittance conversion model described above classifies aerosols for spaceborne lidar. For non-spherical aerosols, the extinction coefficient is calculated using a T-matrix, while for spherical aerosols, the extinction coefficient is calculated using Mie scattering. index;

[0083] according to Calculate the aerosol extinction coefficient at the target wavelength. The calculation results are as follows: Figure 2 As shown;

[0084] Where σ(λ2) is the extinction coefficient of the target wavelength after conversion, and σ(λ1) is the extinction coefficient of the spaceborne lidar wavelength. for index;

[0085] according to The aerosol optical thickness was calculated and compared with the results measured at AERONET sites. Figure 3 As shown;

[0086] Then according to Calculate the aerosol transmittance at the target wavelength;

[0087] Among them, Z C Z represents ground height. sat Represents the highest altitude reached by satellite exploration;

[0088] It should be noted that Mie scattering is a theory describing the interaction between light waves and particles, first proposed by the German physicist Gustav Mie in 1908. Mie scattering is mainly applicable when the particle size is similar to or larger than the wavelength of the incident light, describing the scattering phenomenon of light when interacting with spherical particles (such as water droplets, aerosols, etc.). In Mie scattering, the intensity and distribution of the scattered light depend not only on the wavelength of the incident light and the size of the particles, but also on their shape and refractive index.

[0089] T-matrix scattering is a mathematical method for describing the interaction between scatterers of arbitrary shapes and electromagnetic waves. The T-matrix is ​​an effective characterization of scattering, containing information about the scatterer's geometry, refractive index, and the incident wave. Compared to traditional scattering theory, T-matrix scattering can be used to analyze particles with complex shapes, providing information about the intensity and phase of the scattered light. The calculation of the T-matrix is ​​based on the wave vector of the incident light and the properties of the scatterer, and can depict the distribution characteristics of the scattered light in different directions.

[0090] Step 5) Calculate the atmospheric molecule and ozone transmittance;

[0091] By combining reanalysis data, the transmittance of atmospheric molecules and ozone was calculated using atmospheric molecular scattering theory and ozone absorption spectroscopy.

[0092] When calculating atmospheric molecular scattering, only Rayleigh scattering is considered. The atmospheric molecular extinction coefficient is calculated using the following formula:

[0093]

[0094] Where, N A =6.02214×10 23 (1 / mol) is Avogadro's constant, R a = 8.314472 (J / K / mol) is the molar gas constant, P(Z) is the gas pressure, and T(Z) is the temperature; Q s (λ) is the total Rayleigh scattering cross section caused by each atmospheric molecule in "standard air", calculated as follows:

[0095]

[0096] The transmittance of atmospheric molecules is shown below:

[0097]

[0098] When calculating the ozone extinction coefficient, the atmospheric density must first be calculated:

[0099]

[0100] Where ρ(Z) is the atmospheric density, R is the gas constant (287.058 J / (kg·K)), P(Z) and T(Z) are the air pressure and temperature, respectively. The ozone mass mixing ratio is converted into column density per kilometer:

[0101]

[0102] Where, r o (Z) represents the ozone mixing ratio obtained from ERA5;

[0103] The ozone transmittance is calculated as follows:

[0104]

[0105] Among them, c o Ozone absorption coefficient;

[0106] Step 6), Layered transmittance fusion;

[0107] The atmospheric molecule, ozone, and aerosol transmittance are unified to the same coordinate system at the same height using the pressure layer interpolation method;

[0108] Specifically, based on the extinction coefficients of atmospheric molecules and ozone calculated in step 5), the height is matched using a hierarchical adaptive interpolation method based on the vertical resolution in the spaceborne lidar data, and then the transmittance of atmospheric molecules and ozone is calculated.

[0109] High-precision matching is achieved using a nonlinear interpolation algorithm in the dense aerosol layer, where the extinction coefficient threshold is >0.01km. -1 Determination: Efficient matching is performed using a linear interpolation algorithm within a clean atmosphere, where the clean atmosphere is defined as having an extinction coefficient threshold of ≤0.001km. -1 Judgment: The extinction coefficient of the transition layer is between 0.001 and 0.01 km. -1 The interpolation algorithm and the linear interpolation algorithm are used for matching; the extinction coefficient profile after interpolation is shown in Figure 4.

[0110] Step 7) Calculate the overall atmospheric transmittance;

[0111] Using the atmospheric molecule, ozone, and aerosol transmittances at the same altitude obtained in step 6), multiply them to obtain the atmospheric transmittance of each layer; multiply the atmospheric transmittances of each layer to obtain the atmospheric transmittance of the entire layer.

[0112] Specifically, the transmittance of each component is fused using an algorithm to obtain the transmittance of the entire atmospheric layer;

[0113] The combined transmittance T at each vertical height is expressed as: T = T α ·T m ·T o ;

[0114] Total atmospheric transmittance T A The calculation formula is: T A =T1·T2·····T n Where n is the total number of layers in the vertical direction.

[0115] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A method for inverting atmospheric transmittance using spaceborne lidar and reanalysis data across multiple wavelengths, characterized in that: Based on spaceborne lidar data and reanalysis data, wavelength conversion and data fusion are combined to accurately calculate atmospheric transmittance at different wavelengths; The implementation steps include the following: Step 1) Select the spaceborne lidar data; Download aerosol profile data and vertical feature data, including but not limited to cloud-aerosol discrimination scores, extinction QC marks, extinction uncertainty data, aerosol layer classification and aerosol extinction coefficient; Step 2) Screening the extinction coefficients; Step 3) Generate a spatiotemporal matching dataset; We acquire aerosol extinction coefficient and classification data from spaceborne lidar data, as well as temperature / pressure / ozone mixing ratio data from reanalysis data. We then use a spatiotemporal sliding window matching algorithm to align lidar data and reanalysis data according to spatiotemporal resolution to generate a collaborative dataset. Step 4) Establish an aerosol extinction-transmittance conversion model; Based on aerosol classification data, wavelength conversion parameters are dynamically selected to establish an aerosol extinction-transmittance conversion model. Step 5) Calculate the atmospheric molecule and ozone transmittance; By combining reanalysis data, the transmittance of atmospheric molecules and ozone was calculated using atmospheric molecular scattering theory and ozone absorption spectroscopy. Step 6), Layered transmittance fusion; The atmospheric molecule, ozone, and aerosol transmittance are unified to the same coordinate system at the same height using the pressure layer interpolation method; Step 7) Calculate the overall atmospheric transmittance; Using the atmospheric molecule, ozone, and aerosol transmittances at the same altitude obtained in step 6), multiply them to obtain the atmospheric transmittance of each layer; multiply the atmospheric transmittance of each layer to obtain the atmospheric transmittance of the entire layer.

2. The method for inverting atmospheric transmittance using spaceborne lidar and reanalysis data according to claim 1, characterized in that: Step 2) involves preprocessing the spaceborne lidar data obtained in step 1), including but not limited to filtering effective extinction coefficient data based on cloud-aerosol discrimination scores, removing low-confidence data according to quality control criteria, excluding data points with uncertainties exceeding the threshold, zeroing the extinction coefficient of areas marked as clean atmosphere, removing aerosol data interfered with by high-altitude ice clouds, and limiting the reasonable range of extinction coefficient values.

3. The method for inverting atmospheric transmittance using spaceborne lidar and reanalysis data according to claim 1, characterized in that: Step 3) involves resampling the spaceborne lidar data according to the global grid resolution of the reanalysis data, retaining the data within the lidar's transit trajectory, and generating a spatial matching dataset. The reanalysis data is time-matched based on the acquisition time of the measured aerosol extinction coefficient of the spaceborne lidar; if the reanalysis data used is daily average data, the time nearest neighbor interpolation method is used to match the precise acquisition time of the lidar; if the reanalysis data used is monthly average data, all lidar transit data for the current month are matched with the reanalysis dataset for that month; thus, a collaborative dataset is obtained.

4. The method for inverting atmospheric transmittance using spaceborne lidar and reanalysis data according to claim 1, characterized in that: Step 4) involves classifying the aerosols from the spaceborne lidar. For non-spherical aerosols, the extinction coefficient is calculated using a T-matrix, while for spherical aerosols, the extinction coefficient is calculated using Mie scattering. index; according to Calculate the aerosol extinction coefficient at the target wavelength, where σ(λ2) is the extinction coefficient at the converted target wavelength, and σ(λ1) is the extinction coefficient at the wavelength of the spaceborne lidar. for index; according to The aerosol optical thickness was calculated and compared with the actual measurement site of AERONET, and then based on... Calculate the aerosol transmittance at the target wavelength; where Z C Z represents ground height. sat This represents the highest altitude reached by satellite exploration.

5. The method for inverting atmospheric transmittance using spaceborne lidar and reanalysis data according to claim 1, characterized in that: In step 5), only Rayleigh scattering is considered when calculating atmospheric molecular scattering. The atmospheric molecular extinction coefficient is calculated using the following formula: Where, N A =6.02214×10 23 (1 / mol) is Avogadro's constant, R a = 8.314472 (J / K / mol) is the molar gas constant, P(Z) is the gas pressure, and T(Z) is the temperature; Q s (λ) is the total Rayleigh scattering cross section caused by each atmospheric molecule in "standard air", calculated as follows: The transmittance of atmospheric molecules is shown below: When calculating the ozone extinction coefficient, the atmospheric density must first be calculated: Where ρ(Z) is the atmospheric density, R is the gas constant (287.058 J / (kg·K)), P(Z) and T(Z) are the air pressure and temperature, respectively. The ozone mass mixing ratio is converted into column density per kilometer: Where, r o (Z) represents the ozone mixing ratio obtained from ERA5; The ozone transmittance is calculated as follows: Among them, c o This is the ozone absorption coefficient.

6. The method for inverting multi-wavelength atmospheric transmittance of spaceborne lidar and reanalysis data according to claim 1, characterized in that: In step 6), based on the extinction coefficients of atmospheric molecules and ozone calculated in step 5), a hierarchical adaptive interpolation method is used to perform height matching based on the vertical resolution in the spaceborne lidar data, and then the transmittance of atmospheric molecules and ozone is calculated. High-precision matching is achieved using a nonlinear interpolation algorithm in the dense aerosol layer, where the extinction coefficient threshold is >0.01km. -1 Determination: Efficient matching is performed using a linear interpolation algorithm within a clean atmosphere, where the clean atmosphere is defined as having an extinction coefficient threshold of ≤0.001km. -1 Judgment: In the transition layer, the extinction coefficient is between 0.001 and 0.01 km. -1 The matching is performed using a weighted combination of the nonlinear interpolation algorithm and the linear interpolation algorithm.

7. The method for inverting multi-wavelength atmospheric transmittance of spaceborne lidar and reanalysis data according to claim 1, characterized in that: Step 7) involves using an algorithm to fuse the transmittance of each component and obtain the transmittance of the entire atmospheric layer. The combined transmittance T at each vertical height is expressed as: T = T α ·T m ·T o ; Total atmospheric transmittance T A The calculation formula is: T A =T1·T2····T n Where n is the total number of layers in the vertical direction.

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