RU2586939C1 - Method of determining index of state of atmosphere for anthropogenic pollution sources - Google Patents

Abstract

FIELD: ecology; measurement technology.

SUBSTANCE: invention relates to remote methods of monitoring natural media and to sanitary and epidemiological surveillance of industrial regions. Method involves measuring spectrum of incident light flux that passed thickness of atmosphere, using photometers of global network observations “AERONET” with simultaneous synchronous probing of region using an onboard hyper-spectrometer configured to obtain an image in any spectral channel of visible range, combined processing of recorded signals of photometer and orbital means, determination of index of state of atmosphere q_∑ based regression relationship: q_∑=1.2(λ/λ_et)^1.5·(W_et/W)^2.6, where λ/λ_et-relative change of weighted average wavelength of solar flux recorded by photometers of network “AERONET”, with respect to weight-average wavelength (λ_et) reference, by Planck, of solar flux; W_et/W - relative attenuation of light flux, calculated based on signal, recorded by onboard hyper-spectrometer.

EFFECT: invention enables to separate effects of interaction of light flux with atmosphere and underlying surface and, as a result, increases accuracy of determining index of state.

1 cl, 8 dwg

Description

The invention relates to the field of ecology, in particular to remote methods for monitoring natural environments, and can find application in systems of sanitary and epidemiological control of industrial regions.

Industrial progress is inevitably associated with increased emissions of so-called greenhouse gases into the atmosphere, which are one of the causes of global climate change. Monitoring the state of air pollution is an integral part of the responsibilities of states that have signed the Kyoto Protocol on environmental environmental monitoring. The main types of environmental pollution subject to global monitoring by UNEP are: carbon dioxide CO ₂ , nitrogen dioxide NO ₂ , sulfur dioxide SO ₂ . Under anticyclonal conditions, an accumulation of impurities of both anthropogenic nature and dust smokes from transboundary global transport, whose concentration is hundreds of ppm, occurs in the surface layer.

There is a method of assessing the state of the atmosphere by calculating the index of its state [see, for example, “Methodology for calculating the concentrations of harmful substances in atmospheric emissions in enterprises”, All-Union Normative Document, OND-86, USSR, Gidrometeoizdat, Leningrad, 1987, p. 4-5, as well as “The Yearbook of the State of Atmospheric Pollution in Cities in the Territory of Russia”, edited by E. Yu. Bezuglovoy, GGO them. A.I. Voeikova, St. Petersburg, 1994-1996 - analogue].

Usually, the state index is calculated for five components that determine the main contribution to air pollution:

where m _i [mg / m ³ ] is the average annual concentration of the i-th substance in the atmosphere;

CH _i [mg / m ³ ] - the maximum permissible sanitary norm for the concentration of the i-th substance in atmospheric air, according to GOST;

j is the indicator of the degree of isoeffectiveness of the harmful substance equal to 0.85, 1, 1.3, 1.5 for substances, respectively, of the IV, III, II and I hazard classes;

MPC is the maximum permissible concentration of substances in the atmosphere.

The disadvantages of the known analogues are:

- statistical instability of the method of single local measurements on the ground at control points, as such;

- the uncertainty of the choice of the control points of sampling and the dependence of the measurement result on random turbulence of the atmosphere at the sampling points.

The well-known "Method for the determination of atmospheric pollution in megacities," Patent RU No. 2422859 of 06/27/2011 is the closest analogue. The closest analogue method includes remote measurement by a hyperspectrometer of the spectral characteristics of the reflected light flux from the atmosphere-underlying surface border while simultaneously obtaining an image of a region containing control industrial sites, in the red band 570 ... 670 nm, calculating the weighted average wavelength λ and energy of the reflected flux W, determining atmospheric pollution from regression dependence:

q _∑ [MPC] = 1.2 (λ / λ _et ) ^1.5 · (W _et / W) ^2.6 ;

sorting the pixels of the image by brightness, building a histogram of their distribution and linking the average value of the histogram to the calculated value q _∑ , calculating the absolute distribution of atmospheric pollution over the region in the form of a Rayleigh distribution with calculated numerical characteristics, where:

- q _∑ - the average value of the atmospheric index of the region, MPC;

- λ _et - weighted average wavelength of the reference (according to Planck) solar spectrum;

- W _et - the energy of the reference solar spectrum, normalized relative to the maximum.

The disadvantages of the closest analogue are:

- the impossibility of parametric separation of the effects of the underlying surface and atmospheric "haze" in the recorded resultant signal of the reflected solar flux twice through the atmosphere;

- the need for the mandatory presence in the image of the region of the control industrial site for calibration of the measuring path.

The problem solved by the claimed method is to increase the accuracy of determining the atmospheric state index by remote sensing by additional measurements of the incident light flux spectrum by ground-based AERONET global photometers.

The problem is solved in that the method for determining the atmospheric state index of anthropogenic pollution sources includes measuring the spectrum I (λ) of the incident light flux by AERONET global network photometers geographically located in a controlled region, while simultaneously sensing this territory with a hyperspectrometer mounted on a space carrier, calculation of the relative shift λ / λ _et weighted average wavelength λ of the incident light flux measured by a photometer to the weighted average length non-waves λ _et reference, according to Planck, solar spectrum, calculation of the energy W of the signal twice transmitted through the atmosphere, recorded by the onboard hyperspectrometer, and its attenuation relative to the reference, according to Planck, signal W _et / W, determining the atmospheric state index q _∑ from the regression dependence:

q _∑ = 1.2 (λ / λ _et ) ^1.5 · (W _et / W) ^2.6 ,

, выделение контуров изолиний техногенных нагрузок по всей площади антропогенных источников загрязнения.sorting the pixels of the image of anthropogenic pollution sources obtained by a hyperspectrometer by brightness n _i , identifying the average value of brightness n _cp with the calculated value q _∑ , calculating the absolute atmospheric pollution at each point q _i from the ratio

, the allocation of contours of contours of technogenic loads over the entire area of anthropogenic sources of pollution.

The invention is illustrated by drawings, where:

FIG. 1 - the principle of measuring the incident light flux by the photometer a) and the reflected light flux by orbital means b);

FIG. 2 - reference, according to Planck, solar spectrum c) and the spectrum measured by photometer g);

FIG. 3 - spectral brightness coefficients I (λ) of the objects of the underlying surface in the visible range;

FIG. 4 - regression dependences of the atmospheric state index on the shift of the average wavelength and relative signal attenuation;

FIG. 5 - one of the implementations of I (λ) measurements by an onboard hyperspectrometer, normalized to I (λ) _max ;

Fig 6 is a histogram of the brightness of the image pixels of anthropogenic pollution sources in the entire visible range;

FIG. 7 - contours of technogenic loads over the area of anthropogenic sources of pollution;

FIG. 8 is a functional diagram of a device that implements the method.

The technical essence of the invention is as follows.

There are two types of interaction of the light flux with the atmosphere:

- attenuation of the light flux due to the resonant absorption of energy by impurity gases, followed by fluorescence re-emission of the absorbed energy;

- diffuse dispersion of the flow on aerosols.

In accordance with the Stokes law, re-emission of energy by molecules always occurs at a longer wavelength. As a result of the interaction of the light flux with impurity gas molecules, a shift of the solar spectrum to the long-wave (red) region is observed

[see, for example, R. Mezheris. Laser remote sensing, translation from English, Mir, M, 1987, p. 124, tab. 3.4. The wave numbers of the Raman shift at a wavelength of 337.1 nm]. Below are some extracts from this Table for some impurity smog molecules.

However, a change in the ratio between the spectral components of the reflected light flux also occurs as a result of plant photosynthesis [see, for example, L.I. Chapursky. “Reflective properties of natural objects in the range 400 ... 2500 nm”, part 1, Min. Defense of the USSR, 1986, tables P7, P8, p. 128-129, 130-131].

The graphs of the spectral brightness coefficients (QPS) of the underlying surface objects are illustrated in FIG. 3. As follows from the graphs, the QWs of objects can change several times. Therefore, it is practically impossible to separate the effects of the interaction of the light flux with the atmosphere and the underlying surface in the resulting reflected signal during remote sensing.

In the claimed technical solution, such a separation is implemented by recording the incident light flux, once passing through the entire atmosphere, with a ground photometer and, twice passing through the atmosphere, with an onboard hyperspectrometer.

The well-known international global network for observing atmospheric transparency characteristics "AERONET", which includes about 500 stations [see Internet: http://aeronet.gsfc.nasa.gov/new_web/system_description.html]. The network uses photometers with optical density measurements in spectral regions with wavelengths: 340, 380, 440, 500, 675, 870, 1020 nm. The integral effect of the interaction of the light flux with the components of gas emissions into the atmosphere is to shift the spectrum of the visible range to the red region. The quantitative parameter of such a displacement is the weighted average wavelength λ, calculated as

The weighted average wavelength divides the area under the I (λ) curve (Fig. 2c, d) in half. The weighted average wavelength of the visible range (370 ... 670 nm) of the reference, according to Planck, solar spectrum (Fig. 1) is λ _etal = 500 nm [see, for example, Great Soviet Encyclopedia, ed. AM Prokhorova, Volume 24. Solar radiation, p. 44]. The weighted average value of the spectrum recorded by the photometer, FIG. 2 (d), λ = 560, and their ratio for one of the implementations is λ / λ _et = 560/500 = 1.12.

In the near analogue method, a regression dependence of the state index q _∑ on the relation (λ / λ _et ) is obtained in the form of a power function:

q _∑ = q _∑ (λ / λ _et ) ^1.5

The total attenuation of the light flux that has twice passed through the atmosphere is calculated by processing the signal recorded by the onboard hyperspectrometer.

. Полную эталонную энергию светового потока вычисляют по соотношению Рэлея [см., например, Заездный В.М. «Основы расчетов по статистической радиотехнике», Связь-издат, М, 1964 г., стр. 93-94]:The energy of one quantum (according to Planck's quantum theory) w = hν, where h is the Planck constant, ν is the frequency. Since the wavelength λ = c / ν (c is the speed of light), then the quantum energy:

. The full reference energy of the light flux is calculated by the Rayleigh ratio [see, for example, Zayezhniy V.M. “Fundamentals of calculations in statistical radio engineering”, Svyaz-Izdat, Moscow, 1964, pp. 93-94]:

where I (λ) is the envelope of the spectrum of the reference signal, FIG. 2 (c).

The energy of the signal recorded by the onboard hyperspectrometer is calculated similarly, where the current measurement registers are used as the envelope.

To correctly compare the reference, according to Planck, spectral characteristics and measurement registers, they are brought to a single scale by normalizing with respect to the maximum. In this case, the shooting conditions (height of the Sun, viewing angle) do not affect the result of the calculation of the analyzed parameters.

Since the measurements of modern spectrometers are presented in the form of discrete digital samples, the calculation of the integral is carried out by a specialized mathematical program described below in the implementation example.

The dependence of the atmospheric state index q _∑ on the relative signal attenuation on the propagation path is determined by the regression dependence of the closest analogue, i.e. q _∑ = q _∑ (W _floor / W) ^2.6 .

Then, image processing of anthropogenic pollution sources obtained by the hyperspectrometer in the entire visible range is carried out by constructing a histogram of pixel brightness illustrated in FIG. 6. The average brightness of the histogram pixels n _{sr is} identified with the calculated value q _{∑ of} the state index. The calculation of absolute atmospheric pollution by anthropogenic pollution sources at each point of its image is determined from the ratio of the proportion

According to the data array, the contour lines of anthropogenic loads are visualized using the standard contouring procedure (Fig. 7). The result is a document on the distribution of anthropogenic pressures over the area of anthropogenic pollution sources for environmental decision-making.

An example implementation of the method

The claimed method can be implemented according to the scheme of FIG. 8. The functional diagram of the device comprises a spacecraft (SC) of observation 1 of the Resource type. A hyperspectrometer 2 (of the Astrogon type) is installed on the spacecraft. Frame-by-frame shooting of planned regions containing photometers 3 of the AERONET global network is carried out by commands from the on-board control complex (BCC) 4 from the Mission Control Center (MCC) 5 via the command control radio line 6. The measurement results are recorded in the buffer memory 7 and by BKU teams, in the radio visibility areas of the spacecraft from ground-based points, are reset via the mobile communication channel 8 to the information receiving points (PPI) 9. After the preliminary processing of the frames according to service signs (number of revolution, time of shooting , coordinates of the plot) on the means 10, the information is transmitted to the Thematic Processing Center 11, where through the input device 12 it is entered into the PC 13 in a standard set of elements: processor 14, hard drive 15, random access memory (RAM) 16, display 17, printer 18, keyboard 19. Through the input device 12 to the PC 13 synchronously transmit the measurement results of the spectral characteristics of the incident light flux, once passed through the atmosphere, recorded by the photometer 3 network "AERONET". The results of measurements of emissions of gas components along the spacecraft flight path are displayed on the Internet server 20.

The Astrogon-1 hyperspectrometer has several parallel spectral channels in the visible range with the ability to separately obtain images in each channel or in the entire visible range. Spectral resolution is from 1.5 to 50 nm, quantization resolution is 12 bits and the field of view is 0.11 ° [see, for example, “Vulkan-Astrogon Small Spacecraft with a high-resolution hyperspectrometer”, Engineering Note, RAKA, NIIEM, STC "Reagent", p. 8-10].

One of the implementations of the spectrograms of the hyperspectrometer, normalized with respect to the maximum, is illustrated in FIG. 5. The calculation of the energy of the reflected flow of the register (Fig. 5) is carried out according to a specialized mathematical program.

Luminous flux energy calculation program text

For measurement registers, the implementation of which is illustrated by the graphs of FIG. 2, FIG. 5, the calculated values were W _et = 15.6, W _tech = 11.4.

The atmospheric state index in accordance with the regression dependence:

,

.The average value of the image brightness of anthropogenic pollution sources in the standard quantization scale of 0 ... 255 levels (Fig. 6) is 70, the maximum brightness is 190, the minimum brightness is 20. Recalculated (in proportion) state index values

,

.

All elements of the device that implements the method are made on the existing technical basis.

The efficiency of the device, based on separate measurement of the luminous flux parameters by a photometer (average wavelength shift) and an onboard hyperspectrometer (signal attenuation along the propagation path), is characterized by greater reliability and accuracy.

Claims (1)

A method for determining the atmospheric state index for anthropogenic pollution sources involves measuring the I (λ) spectrum of incident light flux by AERONET global network photometers geographically located in a controlled region, while simultaneously sensing this territory with a hyperspectrometer mounted on a space carrier, calculating the relative shift λ / λ _et weighted average wavelength λ of the incident light flux measured by a photometer to the weighted average wavelength λ _et reference, according to Planck , solar spectrum, calculation of the energy W of the signal twice transmitted through the atmosphere, recorded by the onboard hyperspectrometer, and its attenuation relative to the standard, according to Planck, signal W _et / W, determination of the atmospheric state index q _Σ from the regression dependence
q _Σ = 1.2 (λ / λ _floor ) ^1.5 · (W _floor / W) ^2.6 ,
sorting the pixels of the image of anthropogenic pollution sources obtained by the hyperspectrometer by brightness n _i , identification of the average brightness n _CP with the calculated value q _Σ , calculation of the absolute atmospheric pollution at each point q _i from the ratio $$q_i=\frac{n_{\mathrm{from}R}}{n_i}{q}_{\Sigma }$$

, the allocation of contours of contours of technogenic loads over the entire area of anthropogenic sources of pollution.

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