Atmospheric transmittance acquisition method in haze weather

Abstract

The invention relates to the technical field of atmospheric transmission characteristics, and provides a method for acquiring atmospheric transmittance in haze weather, which comprises the following steps of: acquiring a mixed composition ratio of a plurality of preset haze particle groups forming a preset aerosol type, and acquiring diameters and complex refractive indexes of a plurality of wet haze particles contained in the plurality of preset haze particle groups; and determining the extinction efficiency factor of each wet haze particle according to the diameter and the complex refractive index. And determining the total extinction coefficient of the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio and the extinction efficiency factors corresponding to the plurality of wet haze particles. According to the total extinction coefficient, the atmospheric transmittance is calculated through an atmospheric transmittance calculation function. The calculation of the atmospheric transmissivity is carried out based on the diameter and the complex refractive index of the wet haze particles, and the influence of the preset aerosol type composed of the plurality of preset haze particle groups on the calculation of the atmospheric transmissivity is considered, so that the calculation accuracy of the atmospheric transmissivity is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of atmospheric transmission characteristics, and particularly to a method for obtaining atmospheric transmittance in haze weather. Background Art

[0002] In the field of modern technology, with the continuous innovation and breakthrough of optoelectronic imaging technology, its applications in multiple fields are becoming more diverse and in-depth. A large number of optoelectronic devices play an irreplaceable role in key links such as intelligence collection and situation awareness. However, the performance of optoelectronic imaging systems is extremely vulnerable to factors such as light changes and haze weather. Specifically, in adverse weather conditions, such as haze weather, due to the high atmospheric humidity, and with the change of the relative humidity of the atmospheric environment, the hygroscopic growth of haze particles has a very important impact on the light scattering characteristics, resulting in significant changes in the performance indicators for testing and verifying optoelectronic imaging systems, and thus being unable to accurately and comprehensively reflect the actual performance of optoelectronic imaging systems under adverse weather conditions. Therefore, exploring the hygroscopic growth law and light scattering characteristics of haze particles under different relative humidities in haze weather can provide theoretical support for improving the accuracy of imaging simulation, help related technical fields better cope with various challenges brought by haze weather, and promote the coordinated development of atmospheric environment research and imaging technology.

[0003] Based on this, in recent years, many scholars have studied the impact of the scattering characteristics of aerosols in haze weather on optoelectronic imaging: For example, Ma Jinji et al. calculated the scattering characteristics of aerosol particles in the atmosphere based on the aerosol particle size distribution in the Xiamen sea area; Deng Tao et al., Wang Jing et al. respectively measured the scattering characteristics of aerosol particles in haze weather in Guangzhou and Nanjing; Srini-vasa G. Narasimhan et al. analyzed the imaging effects of various imaging devices and computer vision systems in adverse weather such as haze; Zhao Taifei et al. found that the influence of aggregated clusters and relative humidity on ultraviolet communication mainly focuses on monomer particles with a particle size less than 80 nm; Lou Xiaolong et al. tried methods for restoring optoelectronic images in haze weather.

[0004] However, in the prior art, in the method of calculating the atmospheric transmittance of light transmission in haze weather, the complex refractive index and particle size of dry haze particles are usually directly substituted into the corresponding formula to calculate their scattering characteristic coefficients. However, in actual haze weather conditions, relative humidity is often accompanied, and the hygroscopic growth characteristics of hydrophilic and hydrophobic haze particles will all affect the complex refractive index and particle size to varying degrees, and then the light scattering characteristics of the particles will also change accordingly. Therefore, directly calculating using the particle size and complex refractive index of dry particles reduces the calculation accuracy of obtaining the atmospheric transmittance. And because when calculating the atmospheric transmittance, the influence of different aerosol modes and the haze system with internal mixing methods is not considered and analyzed, the calculation accuracy of obtaining the atmospheric transmittance is also reduced. Summary of the Invention

[0005] Based on this, in view of the above technical problems, it is necessary to provide a method for obtaining the atmospheric transmittance in haze weather.

[0006] An embodiment of the present invention provides a method for obtaining the atmospheric transmittance in haze weather, and the method includes:

[0007] Obtain the mixing composition ratio of a plurality of preset haze particle groups constituting a preset aerosol type, and obtain the diameters and complex refractive indices of a plurality of wet haze particles included in the plurality of preset haze particle groups;

[0008] Determine the extinction efficiency factor of each of the wet haze particles according to the diameter and the complex refractive index;

[0009] Determine the total extinction coefficient of the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of wet haze particles;

[0010] Calculate the atmospheric transmittance according to the total extinction coefficient through an atmospheric transmittance calculation function.

[0011] In one embodiment, the obtaining the diameters and complex refractive indices of a plurality of wet haze particles included in the plurality of preset haze particle groups includes:

[0012] Construct a diameter relationship function and a complex refractive index relationship function between dry haze particles and the corresponding wet haze particles;

[0013] Calculate the diameter of the wet haze particles according to the initial diameter of the dry haze particles through the diameter relationship function;

[0014] Calculate the complex refractive index according to the initial complex refractive index of the dry haze particles, the initial diameter, and the diameter through the complex refractive index relationship function.

[0015] In one embodiment, the diameter relationship function can be defined by the following expression:

[0016]

[0017] where D wet represents the diameter of the wet haze particles, D0 represents the diameter of the dry haze particles, with the unit of μm, H r represents the relative humidity of the atmosphere, and d represents the hygroscopic constant coefficient;

[0018] The complex refractive index relationship function can be defined by the following expression:

[0019] m re = m rw +(m r0 - m rw )G -3

[0020]

[0021] where G represents the diameter hygroscopic growth factor, G = D wet / D0; m re and m ie are respectively the real part and the imaginary part of the complex refractive index corresponding to the wet haze particles, m r0 and m i0 represent the real part and the imaginary part of the complex refractive index corresponding to the dry haze particles; m rw and m iw represent the real part and the imaginary part of the complex refractive index corresponding to water molecules.

[0022] In one embodiment, determining the extinction efficiency factor of each of the wet haze particles according to the diameter and the complex refractive index includes:

[0023] Calculating the extinction efficiency factor according to the diameter and the complex refractive index through an extinction efficiency factor calculation function.

[0024] In one embodiment, the extinction efficiency factor calculation function can be defined by the following expression:

[0025]

[0026] where a = 2α(m re - 1), α represents the scale parameter, α = πD wet / λ.

[0027] 7. In one embodiment, determining the total extinction coefficient of the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to a plurality of the wet haze particles includes:

[0028] Determining the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to a plurality of the wet haze particles;

[0029] Calculating the total extinction coefficient corresponding to the preset aerosol type according to the extinction cross-section through a total extinction coefficient calculation function.

[0030] In one embodiment, determining the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to a plurality of the wet haze particles includes:

[0031] Determining the composition state of the preset aerosol type and an extinction cross-section calculation function, where the composition state is an external mixing state or an internal mixing state, and the extinction cross-section calculation function is a first extinction cross-section calculation function corresponding to the external mixing state or a second extinction cross-section calculation function corresponding to the internal mixing state;

[0032] Calculating the extinction cross-section corresponding to the preset aerosol type through the extinction cross-section calculation function according to the particle distribution function, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of the wet haze particles.

[0033] In one embodiment, the particle distribution function can be defined by the following expression:

[0034]

[0035] where r represents the radius corresponding to each of the wet haze particles, represents the peak radius of the distribution of a plurality of wet haze particles included in the j-th preset haze particle group among the plurality of preset haze particle groups included in the preset aerosol type, σ j represents the standard deviation, and N j is the number of particles per unit volume;

[0036] The first extinction cross-section calculation function can be defined by the following expression:

[0037]

[0038] The second extinction cross-section calculation function can be defined by the following expression:

[0039]

[0040] Among them, represents the extinction efficiency factor of multiple wet haze particles included in the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, f j (r) represents the particle distribution function of the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, M represents the number of groups of the multiple preset haze particle groups included in the preset aerosol type, n j represents the mixing composition ratio of the j-th group among the multiple preset haze particle groups included in the preset aerosol type.

[0041] In one embodiment, the total extinction coefficient calculation function can be defined by the following expression:

[0042]

[0043] Among them, H represents the total number of multiple wet haze particles included in the preset aerosol type.

[0044] In one embodiment, calculating the atmospheric transmittance according to the total extinction coefficient through the atmospheric transmittance calculation function includes:

[0045] Substituting the total extinction coefficient into the atmospheric transmittance calculation function to calculate the atmospheric transmittance;

[0046] Among them, the atmospheric transmittance calculation function includes a first atmospheric transmittance calculation function during horizontal light transmission or a second atmospheric transmittance calculation function during oblique light transmission. The first atmospheric transmittance calculation function can be defined by the following expression:

[0047] τ = exp(-σL)

[0048] Among them, L represents the horizontal transmission distance of light in the haze;

[0049] The second atmospheric transmittance calculation function can be defined by the following expression:

[0050]

[0051] Among them, L represents the horizontal distance during the oblique transmission process of light in the haze, h represents the vertical distance during the oblique transmission process of light in the haze, and h0 represents the elevation of the preset aerosol type.

[0052] The technical solution provided by the embodiment of the present invention has the following advantages compared with the prior art:

[0053] A method for obtaining atmospheric transmittance in haze weather provided by an embodiment of the present invention adopts this method to obtain the mixing composition ratio of multiple preset haze particle groups constituting a preset aerosol type, the diameters of multiple wet haze particles included in the multiple preset haze particle groups, and the complex refractive index. According to the diameter and the complex refractive index, the extinction efficiency factor of each wet haze particle is determined. According to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the multiple wet haze particles, the total extinction coefficient of the preset aerosol type is determined. According to the total extinction coefficient, the atmospheric transmittance is calculated through an atmospheric transmittance calculation function. By adopting this method, when calculating the atmospheric transmittance, it is calculated based on the diameters and the complex refractive index of multiple wet haze particles, and the influence of the preset aerosol type composed of multiple preset haze particle groups on the calculation of the atmospheric transmittance is considered, thereby improving the calculation accuracy of obtaining the atmospheric transmittance. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings herein are incorporated into the specification and constitute a part of this specification, showing embodiments consistent with the present invention and used together with the specification to explain the principles of the present invention.

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for describing the embodiments or the prior art. Obviously, for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0056] Figure 1 It is a schematic flowchart of a method for obtaining atmospheric transmittance in haze weather provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0057] In order to more clearly understand the above-mentioned objects, features, and advantages of the present invention, the following will further describe the solutions of the present invention. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0058] Many specific details are set forth in the following description in order to fully understand the present invention, but the present invention can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0059] In recent years, many scholars have studied the impact of the scattering characteristics of aerosols on optoelectronic imaging under hazy weather conditions: For example, Ma Jinji et al. calculated the scattering characteristics of aerosol particles in the atmosphere based on the aerosol particle size distribution in the Xiamen sea area; Deng Tao et al. and Wang Jing et al. respectively measured the scattering characteristics of aerosol particles under hazy weather conditions in Guangzhou and Nanjing; Srini-vasa G. Narasimhan et al. analyzed the imaging effects of various imaging devices and computer vision systems under harsh weather conditions such as haze; Zhao Taifei et al. found that the influence of aggregated clusters and relative humidity on ultraviolet communication mainly focuses on monomer particles with a particle size less than 80 nm; Lou Xiaolong et al. tried methods for restoring optoelectronic images under hazy weather conditions.

[0060] However, in the existing technology, in the method of calculating the atmospheric transmittance of light transmission under hazy weather conditions, the complex refractive index and particle size of dry haze particles are usually directly substituted into the corresponding formula to calculate their scattering characteristic coefficients. However, in actual hazy weather conditions, relative humidity is often accompanied, and the hygroscopic growth characteristics of hydrophilic and hydrophobic haze particles will all affect the complex refractive index and particle size to varying degrees, thereby changing the scattering characteristics of the particles to light. Therefore, directly calculating using the particle size and complex refractive index of dry particles reduces the calculation accuracy of obtaining the atmospheric transmittance. And because when calculating the atmospheric transmittance, the influence of different aerosol modes and the haze system with internal mixing methods is not considered and analyzed, the calculation accuracy of obtaining the atmospheric transmittance is also reduced.

[0061] Therefore, the present invention provides a method for obtaining the atmospheric transmittance under hazy weather conditions. By obtaining the mixing composition ratio of a plurality of preset haze particle groups constituting a preset aerosol type, as well as obtaining the diameters and complex refractive indices of a plurality of wet haze particles included in the plurality of preset haze particle groups. According to the diameter and complex refractive index, the extinction efficiency factor of each wet haze particle is determined. According to the particle distribution function, mixing composition ratio of the preset aerosol type, and the extinction efficiency factors corresponding to the plurality of wet haze particles, the total extinction coefficient of the preset aerosol type is determined. According to the total extinction coefficient, the atmospheric transmittance is calculated through an atmospheric transmittance calculation function. By adopting this method, when calculating the atmospheric transmittance, it is calculated based on the diameters and complex refractive indices of a plurality of wet haze particles, and the influence of the preset aerosol type composed of a plurality of preset haze particle groups on the calculation of the atmospheric transmittance is considered, thereby improving the calculation accuracy of obtaining the atmospheric transmittance.

[0062] In one embodiment, as Figure 1 shown, Figure 1 is a schematic flowchart of a method for obtaining the atmospheric transmittance under hazy weather conditions provided by an embodiment of the present invention, which specifically includes the following steps:

[0063] S10: Obtain the mixing composition ratios of multiple preset haze particle groups that make up a preset aerosol type, as well as obtain the diameters and complex refractive indices of multiple wet haze particles included in the multiple preset haze particle groups.

[0064] Among them, the preset aerosol type refers to the fact that due to the different compositions of multiple groups of preset haze particle groups that make up the atmospheric aerosol mode, there are multiple different preset types of atmospheric aerosol types. As shown in Table 1 below, the preset aerosol type includes: clean land type, slightly polluted land type, moderately polluted land type, and heavily polluted land type. For different preset aerosol types, there are different compositions of preset haze particle groups and their related composition parameters. The preset haze particle groups include: soluble haze particle groups, insoluble haze particle groups, and bituminous coal haze particle groups. For each preset haze particle group, it contains multiple preset haze particles, and its related composition parameters include: particle number N j 、particle mass M j 、mixing composition ratio n j 、mass mixing ratio m j etc. Among them, the particle number N j represents the number of particles contained in the preset haze particle group, the particle mass M j represents the particle mass contained in the preset haze particle group, the mixing composition ratio n j represents the proportion of the number of each preset haze group in the preset aerosol type, and the mass mixing ratio m j represents the proportion of the mass of each preset haze group in the preset aerosol type.

[0065] Exemplarily, the clean land type is composed of soluble haze particle groups and insoluble haze particle groups, but is not limited thereto. The present invention does not specifically limit it, and those skilled in the art can set it according to the actual situation.

[0066] Table 1 Composition of each preset aerosol type

[0067]

[0068] The above-mentioned wet haze particles refer to the fact that dry haze particles will absorb moisture due to the relative change in atmospheric humidity caused by haze weather. Based on this, after absorbing moisture, the particle diameter and complex refractive index of wet haze particles will also change relatively compared to dry haze particles.

[0069] Specifically, obtain the mixing composition ratios corresponding to multiple preset haze particle groups that make up a preset aerosol type under haze weather, and obtain the diameters and complex refractive indices corresponding to multiple wet haze particles included in the multiple preset haze particle groups respectively.

[0070] Optionally, based on the above embodiments, in some embodiments of the present invention, due to the relative change in atmospheric humidity caused by the haze weather, dry haze particles will absorb moisture. After absorbing moisture, the particle diameter and complex refractive index of the wet haze particles will also change relative to the dry haze particles. Based on this, one implementation method for obtaining the diameters and complex refractive indices of multiple wet haze particles included in multiple preset haze particle groups can be as follows:

[0071] S101: Construct a diameter relationship function and a complex refractive index relationship function between dry haze particles and the corresponding wet haze particles.

[0072] Specifically, in order to obtain the diameter of the wet haze particles corresponding to the dry haze particles and the complex refractive index of the wet haze particles, a diameter relationship function and a complex refractive index relationship function between the dry haze particles and the wet haze particles are constructed.

[0073] Optionally, based on the above embodiments, in some embodiments of the present invention, the diameter relationship function can be defined by the following expression:

[0074]

[0075] where D wet represents the diameter of the wet haze particles, D0 represents the diameter of the dry haze particles, with the unit of μm, H r represents the relative atmospheric humidity, and d represents the hygroscopic constant coefficient. For the hygroscopic constant coefficient, when it is determined that the haze particles are soluble haze particles, the hygroscopic constant coefficient takes a value of 3.9; when it is determined that the haze particles are insoluble haze particles or soot particles, the hygroscopic constant coefficient takes a value of 5.8.

[0076] Optionally, based on the above embodiments, in some embodiments of the present invention, for the complex refractive index which is a complex number composed of a real number and an imaginary number, based on this, the complex refractive index relationship function can be defined by the following expression:

[0077] m re = m rw +(m r0 - m rw )G -3

[0078]

[0079] where G represents the diameter hygroscopic growth factor, G = D wet / D0; m re and m ie are respectively the real part and the imaginary part of the complex refractive index corresponding to the wet haze particles, m r0 and m i0represent the real part and the imaginary part of the complex refractive index corresponding to dry haze particles; m rw and m iw represent the real part and the imaginary part of the complex refractive index corresponding to water molecules.

[0080] S102: According to the initial diameter of dry haze particles, calculate the diameter of wet haze particles through the diameter relationship function.

[0081] Specifically, substitute the initial diameter of dry haze particles into the diameter relationship function, and calculate the diameter of the wet haze particles corresponding to the dry haze particles through the diameter relationship function.

[0082] S103: According to the initial complex refractive index, initial diameter and diameter of dry haze particles, calculate the complex refractive index through the complex refractive index relationship function.

[0083] Specifically, substitute the initial complex refractive index, initial diameter and diameter of dry haze particles into the complex refractive index relationship function, and calculate the complex refractive index of the wet haze particles corresponding to the dry haze particles through the complex refractive index relationship function.

[0084] In this way, this embodiment can accurately obtain the diameters and complex refractive indices of each wet haze particle in haze weather by constructing a diameter relationship function and a complex refractive index relationship function, avoiding the low calculation accuracy in subsequent calculation of atmospheric transmittance due to water absorption.

[0085] S11: Determine the extinction efficiency factor of each wet haze particle according to the diameter and the complex refractive index.

[0086] Among them, the extinction efficiency factor is one of the scattering characteristics of wet haze particles, and the extinction efficiency factor can be used to measure the characteristic of haze particles absorbing water.

[0087] Specifically, determine the extinction efficiency factor corresponding to each wet haze particle according to the diameters and complex refractive indices of multiple wet haze particles.

[0088] Optionally, based on the above embodiment, in some embodiments of the present invention, one implementation manner of S11 may be:

[0089] S111: Calculate the extinction efficiency factor according to the diameter and the complex refractive index through the extinction efficiency factor calculation function.

[0090] Specifically, substitute the diameters and complex refractive indices of each wet haze particle into the extinction efficiency factor calculation function, and calculate the extinction efficiency factor of each wet haze particle through the extinction efficiency factor calculation function.

[0091] Optionally, based on the above embodiment, in some embodiments of the present invention, the extinction efficiency factor calculation function may be defined by the following expression:

[0092]

[0093] where a = 2α(m re - 1), α represents the scale parameter, and α = πD wet / λ.

[0094] S12: Determine the total extinction coefficient of the preset aerosol type according to the particle distribution function, mixing composition ratio, and extinction efficiency factors corresponding to multiple wet haze particles of the preset aerosol type.

[0095] Among them, the particle distribution function is used to characterize the distribution of multiple wet haze particles of multiple preset haze particle groups included in the preset aerosol type.

[0096] Optionally, on the basis of the above embodiments, in some embodiments of the present invention, the particle distribution function can be defined by the following expression:[[]]

[0097]

[0098] where r represents the radius corresponding to each wet haze particle, represents the peak radius of the distribution of multiple wet haze particles included in the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, and σ j represents the standard deviation, and N j is the number of particles per unit volume.

[0099] Optionally, on the basis of the above embodiments, in some embodiments of the present invention, referring to Table 2 below: It can be seen from the characteristic parameter table of the normal logarithmic spectrum distribution of each preset haze particle group that its characteristic parameters include: the peak radius of the distribution r modN , or r modV , the minimum radius r min corresponding to the haze particles, or the maximum radius r max , the density ρ, etc. Specifically, for the peak radius of the distribution, when the peak radius of the distribution is used to represent the particle number concentration of multiple wet haze particles of multiple preset haze particle groups included in the preset aerosol type, then determine to take the parameter value corresponding to r modN , and when the peak radius of the distribution is used to represent the mass concentration of multiple wet haze particles of multiple preset haze particle groups included in the preset aerosol type, then determine to take the parameter value corresponding to r modV .

[0100] Furthermore, the r modN parameter value is more sensitive to small particle haze particles, and r modVMore sensitive to large particulate haze particles. Exemplarily, in the study of small particulate haze particles such as PM2.5, r modN is used as a parameter of the particle distribution function. In the study of large particulate haze particles PM10, r modV is used as a parameter of the particle distribution function. However, it is not limited to this. The present invention does not specifically limit it, and those skilled in the art can set it according to the actual situation.

[0101] Table 2 Characteristic parameters of the normal logarithmic spectrum distribution of each preset haze particle group

[0102] Component σ <![CDATA[r modN (μm)]]> <![CDATA[r modV (μm)]]> <![CDATA[r min (μm)]]> <![CDATA[r max (μm)]]> ρ Insolubility 2.51 0.471 6 0.005 20 2 Solubility 2.24 0.021 0.15 0.005 20 1.8 Sootiness 2 0.12 0.05 0.005 20 1

[0103] Optionally, on the basis of the above embodiments, in some embodiments of the present invention, one implementation manner of S12 can be:

[0104] S121: Determine the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to a plurality of wet haze particles.

[0105] Specifically, pre-construct the particle distribution function of the preset aerosol type, and obtain the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to a plurality of wet haze particles.

[0106] Optionally, on the basis of the above embodiments, in some embodiments of the present invention, one implementation manner of S121 can be:

[0107] S1211: Determine the composition state of the preset aerosol type and the extinction cross-section calculation function.

[0108] Wherein, the composition state is an external mixing state or an internal mixing state. The external mixing state means that the multiple wet haze particles of multiple preset haze particle groups constituting the preset aerosol type can only contain a single component and exist independently of each other. The way of constituting the preset aerosol type in this way is the external mixing state. The internal mixing state means that the multiple wet haze particles of multiple preset haze particle groups of the preset aerosol type are all composed of different particles mixed. There are two processing ideas for the internal mixing method: one is to equivalent the mixed particles into a uniform dielectric sphere model; the other idea is to regard the mixed particles as a non-uniform core-shell sphere model.

[0109] The above extinction cross-section calculation function is the first extinction cross-section calculation function corresponding to the external mixing state or the second extinction cross-section calculation function corresponding to the internal mixing state.

[0110] S1212: Calculate the extinction cross-section corresponding to a preset aerosol type through an extinction cross-section calculation function based on the particle distribution function, the mixing composition ratio, and the extinction efficiency factors corresponding to multiple wet haze particles.

[0111] Specifically, determine whether the composition state of the preset aerosol type belongs to the external mixing state or the internal mixing state. When it is determined that the composition state of the preset aerosol type belongs to the external mixing state, calculate the extinction cross-section corresponding to the preset aerosol type through a first extinction cross-section calculation function based on the particle distribution function, the mixing composition ratio, and the extinction efficiency factors corresponding to multiple wet haze particles.

[0112] Optionally, based on the above embodiments, in some embodiments of the present invention, the first extinction cross-section calculation function can be defined by the following expression:

[0113]

[0114] Wherein, represents the extinction efficiency factor of multiple wet haze particles included in the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, f j (r) represents the particle distribution function of the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, M represents the number of groups of the multiple preset haze particle groups included in the preset aerosol type, n j represents the mixing composition ratio of the j-th group among the multiple preset haze particle groups included in the preset aerosol type.

[0115] Optionally, when it is determined that the composition state of the preset aerosol type belongs to the internal mixing state, calculate the extinction cross-section corresponding to the preset aerosol type through a second extinction cross-section calculation function based on the particle distribution function and the extinction efficiency factors corresponding to multiple wet haze particles.

[0116] Optionally, based on the above embodiments, in some embodiments of the present invention, the second extinction cross-section calculation function can be defined by the following expression:

[0117]

[0118] It should be noted that when it is determined that the composition state of the preset aerosol type belongs to the internal mixing state, the complex refractive index of the wet haze particles is determined according to the formula m mix = ∫m j p j where m i represents the complex refractive index exponent of the j-th single preset haze particle group, and pi represents the mixing composition ratio of the j-th single preset haze particle group. Further, substitute the obtained complex refractive index into the extinction efficiency factor calculation function to calculate the extinction efficiency factor.

[0119] S122: Calculate the total extinction coefficient corresponding to the preset aerosol type according to the extinction cross-section through the total extinction coefficient calculation function.

[0120] Specifically, substitute the extinction cross-section of the preset aerosol type into the total extinction coefficient calculation function to calculate the total extinction coefficient corresponding to the preset aerosol type through the total extinction coefficient calculation function.

[0121] Optionally, based on the above embodiments, in some embodiments of the present invention, the total extinction coefficient calculation function can be defined by the following expression:

[0122]

[0123] Wherein, H represents the total number of a plurality of wet haze particles included in the preset aerosol type.

[0124] S13: Calculate the atmospheric transmittance according to the total extinction coefficient through the atmospheric transmittance calculation function.

[0125] Specifically, substitute the total extinction coefficient of the preset aerosol type into the atmospheric transmittance calculation function to calculate the atmospheric transmittance through the atmospheric transmittance calculation function.

[0126] Optionally, based on the above embodiments, in some embodiments of the present invention, the atmospheric transmittance calculation function includes a first atmospheric transmittance calculation function for horizontal light transmission or a second atmospheric transmittance calculation function for slant-path light transmission. Based on this, the first atmospheric transmittance calculation function can be defined by the following expression:

[0127] τ = exp(-σL)

[0128] Wherein, L represents the horizontal transmission distance of light in the haze;

[0129] The second atmospheric transmittance calculation function can be defined by the following expression:

[0130]

[0131] Wherein, L represents the horizontal distance during the slant-path transmission of light in the haze, h represents the vertical distance during the slant-path transmission of light in the haze, and h0 represents the scale height of the preset aerosol type. The value of the scale height can be determined according to the actual situation.

[0132] Thus, the method for obtaining the atmospheric transmittance under haze weather provided in this embodiment obtains the mixing composition ratios of multiple preset haze particle groups that make up the preset aerosol type, the diameters of multiple wet haze particles included in the multiple preset haze particle groups, and the complex refractive index. According to the diameter and the complex refractive index, the extinction efficiency factor of each wet haze particle is determined. According to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the multiple wet haze particles, the total extinction coefficient of the preset aerosol type is determined. According to the total extinction coefficient, the atmospheric transmittance is calculated through the atmospheric transmittance calculation function. By adopting this method, when calculating the atmospheric transmittance, it is calculated based on the diameters and the complex refractive index of multiple wet haze particles, and the influence of the preset aerosol type composed of multiple preset haze particle groups on the calculation of the atmospheric transmittance is considered, thereby improving the calculation accuracy of obtaining the atmospheric transmittance.

[0133] It should be understood that although Figure 1 the steps in the flowchart of Figure 1 are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover,

[0134] Those of ordinary skill in the art can understand that all or part of the processes in the methods of the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, database, or other medium used in the various embodiments provided by the present invention can include at least one of non-volatile and volatile memories. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static random access memory (SRAM) and dynamic random access memory (DRAM), etc.

[0135] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0136] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A method for obtaining atmospheric transmittance under haze weather, characterized in that, Including: Obtaining the mixing composition ratio of a plurality of preset haze particle groups constituting a preset aerosol type, obtaining the diameters of a plurality of wet haze particles included in the plurality of preset haze particle groups, and the complex refractive index; Determining the extinction efficiency factor of each of the wet haze particles according to the diameter and the complex refractive index; Determining the total extinction coefficient of the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of wet haze particles; Calculating the atmospheric transmittance according to the total extinction coefficient through an atmospheric transmittance calculation function.

2. The method according to claim 1, characterized in that The obtaining the diameters of a plurality of wet haze particles included in the plurality of preset haze particle groups and the complex refractive index includes: Constructing a diameter relationship function and a complex refractive index relationship function between dry haze particles and the corresponding wet haze particles; Calculating the diameter of the wet haze particles according to the initial diameter of the dry haze particles through the diameter relationship function; Calculating the complex refractive index according to the initial complex refractive index of the dry haze particles, the initial diameter, and the diameter through the complex refractive index relationship function.

3. The method according to claim 2, wherein The diameter relationship function can be defined by the following expression: where D wet represents the diameter of the wet haze particles, D0 represents the diameter of the dry haze particles, with the unit of μm, and H r represents the relative humidity of the atmosphere, and d represents the hygroscopic constant coefficient; The complex refractive index relationship function can be defined by the following expression: m re = m rw +(m r0 - m rw )G -3 Among them, G represents the diameter hygroscopic growth factor, G = D wet / D0; m re and m ie are respectively the real part and the imaginary part of the complex refractive index corresponding to the wet haze particles, m r0 and m i0 represent the real part and the imaginary part of the complex refractive index corresponding to the dry haze particles; m rw and m iw represent the real part and the imaginary part of the complex refractive index corresponding to water molecules.

4. The method according to claim 3, wherein The determining the extinction efficiency factor of each of the wet haze particles according to the diameter and the complex refractive index includes: Calculating the extinction efficiency factor according to the diameter and the complex refractive index through an extinction efficiency factor calculation function.

5. The method according to claim 4, wherein The extinction efficiency factor calculation function can be defined by the following expression: where a = 2α(m re - 1), α represents the scale parameter, α = πD wet / λ.

6. The method according to claim 5, wherein The determining the total extinction coefficient of the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of wet haze particles includes: Determining the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of wet haze particles; Calculating the total extinction coefficient corresponding to the preset aerosol type according to the extinction cross-section through a total extinction coefficient calculation function.

7. The method according to claim 6, wherein The determining the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function of the preset aerosol type, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of wet haze particles includes: Determining the composition state of the preset aerosol type and an extinction cross-section calculation function, where the composition state is an external mixing state or an internal mixing state, and the extinction cross-section calculation function is a first extinction cross-section calculation function corresponding to the external mixing state or a second extinction cross-section calculation function corresponding to the internal mixing state; Calculating the extinction cross-section corresponding to the preset aerosol type according to the particle distribution function, the mixing composition ratio, and the extinction efficiency factors corresponding to the plurality of wet haze particles through the extinction cross-section calculation function.

8. The method according to claim 7, wherein The particle distribution function can be defined by the following expression: where r represents the radius corresponding to each of the wet haze particles represents the peak radius of the distribution of a plurality of wet haze particles included in the j-th preset haze particle group among the plurality of preset haze particle groups included in the preset aerosol type, and σ j represents the standard deviation, and N j is the number of particles per unit volume; The first extinction cross-section calculation function can be defined by the following expression: The second extinction cross-section calculation function can be defined by the following expression: Among them, represents the extinction efficiency factor of the multiple wet haze particles included in the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, f j (r) represents the particle distribution function of the j-th preset haze particle group among the multiple preset haze particle groups included in the preset aerosol type, M represents the number of groups of the multiple preset haze particle groups included in the preset aerosol type, n j represents the mixing composition ratio of the j-th group among the multiple preset haze particle groups included in the preset aerosol type.

9. The method according to claim 6, wherein The total extinction coefficient calculation function can be defined by the following expression: where H represents the total number of multiple wet haze particles included in the preset aerosol type.

10. The method according to claim 9, characterized in that, Calculating the atmospheric transmittance according to the total extinction coefficient through the atmospheric transmittance calculation function includes: Substituting the total extinction coefficient into the atmospheric transmittance calculation function to calculate the atmospheric transmittance; where the atmospheric transmittance calculation function includes a first atmospheric transmittance calculation function for horizontal light transmission or a second atmospheric transmittance calculation function for slant-path light transmission, and the first atmospheric transmittance calculation function can be defined by the following expression: τ = exp(-σL) where L represents the horizontal transmission distance of light in the haze; The second atmospheric transmittance calculation function can be defined by the following expression: where L represents the horizontal distance in the slant-path transmission process of light in the haze, h represents the vertical distance in the slant-path transmission process of light in the haze, and h0 represents the scale height of the preset aerosol type.

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