A satellite remote sensing ozone precursor tracing method and system for urban agglomeration

Abstract

This invention discloses a satellite remote sensing method and system for tracing ozone precursors in urban agglomerations, relating to the fields of ecological environment monitoring and air pollution control. The system includes a scene time-series sampling module, a relay ternary code generation module, a candidate chain preliminary evaluation module, a chain source code generation module, and a tracing output module. Based on multi-temporal column concentrations, HCHO column concentrations, ozone station concentrations, boundary layer height, wind field, urban boundaries, and land use information, the system generates morning initiation scene values, afternoon HCHO takeover scene values, and evening ozone receptor scene values, and constructs initiation codes, VOC takeover codes, and receptor lag codes. The system combines inter-city transmission time differences and ternary code balance to generate relay chain source codes, outputting the initiating city, VOC takeover city, ozone receptor city, and chain break verification fragments to characterize the cross-city relay tracing process of ozone precursors in urban agglomerations.

Description

Technical Field

[0001] This invention relates to the field of ecological environment monitoring and air pollution control technology, specifically to a satellite remote sensing method and system for tracing ozone precursors in urban clusters. Background Technology

[0002] In existing ozone source analysis of urban agglomerations, a common approach is to analyze individual cities... The concentrations of ozone, HCHO, and ozone, or emission inventories are statistically analyzed and ranked according to administrative regions or fixed grids. This method can describe the pollution level of a city or grid at a specific time, but it struggles to capture the cross-city relay characteristics of ozone formation. In actual pollution processes, upwind cities... Emissions form the initial signal, VOCs become active in intermediate cities in the afternoon and participate in conversion, and ozone peaks occur in downwind cities in the evening. These three events occur in sequence in time and are spatially influenced by wind fields. If the source is traced solely based on the concentration levels of individual cities, it is easy to mistakenly identify ozone recipient cities as major emitting cities, and it is also difficult to explain why ozone concentrations are high even when local emissions are not significant.

[0003] The aforementioned shortcomings typically arise from three aspects: firstly, satellites First, HCHO data and ground-level ozone data differ in spatial scale, temporal frequency, and observed objects, resulting in only scattered indicators without chain processing. Second, wind fields within urban agglomerations alter precursor transport paths, making it difficult to represent the continuous process of upwind initiation, mid-term transport, and downwind receptors through fixed administrative boundary analysis. Third, ozone formation exhibits time-lag characteristics. Anomalies, HCHO growth, and ozone peaks do not occur simultaneously in the same city or at the same time. When this happens, the chain of responsibility for cross-city pollution is broken, the attribution of pollution to recipient cities is biased, the identification of upwind initiating cities and intermediate VOC relay cities is insufficient, and subsequent joint prevention and control efforts within city clusters lack segmented verification evidence. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a satellite remote sensing method and system for tracing ozone precursors in urban clusters, solving the problems mentioned in the background section.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: a satellite remote sensing ozone precursor tracing system for urban agglomerations, comprising a scene time-series sampling module, a relay ternary code generation module, a candidate chain preliminary evaluation module, a chain source code generation module, and a tracing output module; Scene time-series sampling module analyzes continuous multi-temporal phases of urban agglomerations Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, to obtain a set of start-up scenario values; The relay ternary code generation module generates the code based on the set of starting scenario values. The initiation code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; The candidate chain initial evaluation module generates the candidate chain evaluation quantity E based on the initiation code feature set QF and the inter-city transmission time difference Td; The chain source code generation module uses the candidate chain evaluation quantity E as a basis and combines the ternary code balance degree G to generate the relay chain source code Cs; The source tracing output module generates the chain proportion based on the Cs source code of each relay chain and outputs it. Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments.

[0006] Preferably, the scene temporal sampling module includes a multi-source scene normalization unit and a relay scene slicing unit; Multi-source scene unification unit receives continuous multi-temporal phases of urban agglomerations Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, and organize data from different sources, time intervals and spatial scales into the same urban agglomeration spatiotemporal framework for unified spatiotemporal organization; First, analyze the coverage status of satellite pixels and city boundaries to obtain the coverage data for each city at each time point. HCHO area-weighted value; Every city at every moment The HCHO area-weighted value uses the coverage area of ​​each satellite pixel within the city boundary as the weight, and assigns weights to each pixel at the current time. The city-level results were obtained by weighted averaging of column concentrations and HCHO column concentrations. Column concentration values ​​and city-level HCHO column concentration values; Each city at each observation time The area-weighted value refers to first identifying all satellite pixels that have coverage with the boundary of city i, and then calculating the coverage area of ​​each satellite pixel within the boundary of city i; then calculating the area of ​​each satellite pixel at time t. The column concentration is multiplied by its coverage area within the boundary of city i to obtain the column concentration of each pixel relative to city i. Area contribution; then all pixels The sum of area contributions is divided by the total coverage area of ​​all pixels falling within the boundary of city i to obtain the area contribution of city i at time t. Area-weighted column concentration.

[0007] The HCHO area-weighted value for each city at each observation time is calculated by first determining all satellite pixels that cover the boundary of city i, and then calculating the coverage area of ​​each satellite pixel within the boundary of city i; then multiplying the HCHO column concentration of each satellite pixel at time t by its coverage area within the boundary of city i to obtain the HCHO area contribution of each pixel to city i; finally, summing the HCHO area contributions of all pixels and dividing by the sum of the coverage areas of all pixels within the boundary of city i to obtain the HCHO area-weighted column concentration of city i at time t. Further analysis of the effect of boundary layer height on The effect of column concentration on near-surface expression, obtaining Startup base quantity HCHO's basic volume and basal amount of ozone receptors The formula is as follows: ; ; In the formula, This indicates that city i at time t Area-weighted column concentration, This represents the boundary layer height of city i at time t. This represents the area-weighted column concentration of HCHO in city i at time t. Baseline amount of ozone receptors The method for obtaining the ozone concentration is as follows: First, determine all ozone ground monitoring stations in city i that are involved in the calculation; then, obtain the ozone concentration of each station at time t and determine the representative weight of each station to city i; then, multiply the ozone concentration of each station by its representative weight to obtain the weighted contribution of each station to the basic amount of ozone receptors in the city; finally, sum the weighted contributions of all stations and divide by the sum of the representative weights of all stations to obtain the basic amount of ozone receptors in city i at time t. Analyze the degree of wind direction transport alignment from city i to city j to obtain the intercity transport volume. The formula is as follows: ; In the formula, Specifically, at time t, the amount of transport overlap from city i to city j indicates whether the current wind direction is favorable for the transport of pollutants from city i to city j. This represents the spatial location vector of city i, taking the city's center point. This represents the spatial location vector of city j, taken as the city's center point. The wind vector at time t is composed of the east-west and north-south components of the wind speed. Relay scene slicing unit based on intercity transport volume , Startup base quantity HCHO's basic volume and basal amount of ozone receptors Based on this, generate the morning The formulas for the starting scenario value, the afternoon HCHO catchment scenario value, and the evening ozone receptor scenario value are as follows: ; In the formula, Indicates the morning of city i Startup scene value, This indicates that city i is in the morning period. Start the basic quantity. This indicates that city i experiences similar weather conditions on the morning of the day. The baseline value for starting basic quantity, This represents the proportion of road land use in city i, obtained by comparing the area of ​​roads within the city to the area of ​​the city within the current effective satellite observation pixel coverage. This represents the amount of transported data from city i to city j during the morning session. ; In the formula, This represents the afternoon HCHO load factor for city j. This represents the baseline amount of HCHO absorbed by city j during the afternoon period. The baseline amount of HCHO absorbed by city J during the morning session. This represents the land use acceptance weight of city j, with a value ranging from 0 to 1. This represents the amount of transported data from city i to city j during the intermediate time period. ; In the formula, This represents the evening ozone receptor scene value for city k. This represents the baseline amount of ozone receptors in city k during the evening period. This represents the baseline amount of ozone receptors in city k during midday. This represents the amount of transported data from city j to city k during the afternoon period. This represents the time continuity factor from city j to city k, with a value ranging from 0 to 1; The morning will be obtained The starting scenario value, the afternoon HCHO receiving scenario value, and the evening ozone receptor scenario value were fitted to obtain the starting scenario value set.

[0008] Preferably, the relay ternary code generation module includes a link candidate binding unit and a ternary code fitting unit; The link candidate binding unit analyzes the morning session in the set of startup scenario values. Startup Scenario Value The city with the highest median score gains the upper hand. Start with candidate city A, then search for the afternoon HCHO carrying capacity value of city j along the downwind direction of city A from morning to noon. Cities with high median values ​​were selected as candidate cities for VOCs to take over; subsequently, ozone receptor values ​​for city k in the evening were retrieved along the downwind direction from city B from afternoon to evening. Cities with the highest median ozone concentrations are selected as candidate cities for ozone receptors (C). During the search process, the three cities were combined and ranked, and the candidate chains were bound together in chronological order by "morning start, afternoon takeover, evening recipient". ; When ozone in a certain city k is affected by the scene value at dusk When the ozone concentration exceeds the preset scene threshold, but there is a lack of afternoon HCHO carryover scene values ​​in the upwind direction of city j. In the case of receiving a candidate city, the current city is retained as an isolated receptor fragment and does not enter the complete candidate chain.

[0009] Preferably, the ternary code fitting unit is based on the candidate chain. generate The initiation code B1, the VOC successor code B2, and the receptor hysteresis code B3 are fitted together to form the initiation code feature set QF. Start code B1 is obtained using the following formula: ; In the formula, This indicates the morning hours in city A. Start the basic quantity. This indicates that in city A, on similar weather days, the morning... The baseline value for starting basic quantity, Indicates the morning in city A Positive outliers are counted as zero if they are less than zero. This represents the average transport overlap from city A to city B during the morning period, where A represents upwind. The candidate cities for starting are: B represents the intermediate VOC relay candidate city, and C represents the downwind ozone receptor candidate city. VOC successor code B2 is obtained using the following formula: ; In the formula, This represents the baseline volume of HCHO absorbed by city B during the afternoon. This represents the baseline HCHO intake in City B during the morning session. This indicates the positive increase in HCHO in city B during the afternoon; values ​​less than zero are counted as zero. This represents the land use carrying capacity of City B, indicating the degree to which spatial conditions such as industrial land, solvent use areas, and vegetation cover in City B support the carrying capacity of HCHO in the afternoon. The value ranges from 0 to 1. This represents the average transport overlap from city A to city B during the intermediate period; The receptor hysteresis code B3 is obtained using the following formula: ; In the formula, This represents the baseline amount of ozone receptors in city C during the evening. This represents the baseline amount of ozone receptors in city C during midday. This represents the positive increase in ozone levels in city C at dusk; values ​​less than zero are counted as zero. This represents the average transport overlap from city B to city C during the afternoon period. This represents the time continuity factor from city B to city C, used to indicate whether the peak HCHO activity time in city B and the peak ozone time in city C follow a sequential order. The value ranges from 0 to 1.

[0010] Preferably, the candidate chain preliminary evaluation module includes a transmission time difference resolution unit and a relay strength evaluation unit; Transmission Time Difference Resolution Unit (TTD) uses the starting code feature set QF and candidate chains. Based on; from The morning of start code B1 Extracting City A from Startup Records The start time tN is determined, and then the ozone peak time tO for city C is extracted from the ozone receptor record belonging to receptor hysteresis code B3. morning Startup records refer to the morning data of city A retained when B1 is generated. Start-up process information; Ozone receptor records refer to the ozone receptor process information of city C retained when B3 is generated; Analyze the spatial distances from city A to city B and from city B to city C, and the average wind speeds along the chain direction during the corresponding time periods, to obtain... Transmission time and Transmission time And calculate the inter-city transmission time difference Td; The specific process is as follows: When analyzing spatial distances, instead of directly using the distances between urban administrative centers, we first start with the morning distances of city A. Determined in the startup scenario The spatial center of the starting area is determined from the HCHO receiving scenario in city B in the afternoon, and the distance between the two spatial centers is taken as the chain distance from city A to city B. For the chain segment from city B to city C, the spatial center of the ozone receptor area is determined from the ozone receptor scenario in city C in the evening, and the distance between the spatial center of the HCHO receiving area in city B and the spatial center of the ozone receptor area in city C is taken as the chain distance from city B to city C.

[0011] When analyzing the average wind speed along the chain direction during the corresponding time period, the chain segment direction is first determined based on two spatial centers, and then the wind field data for the corresponding time period of the chain segment is extracted. Subsequently, the wind field direction is compared with the chain segment direction, and only the wind speed component transmitted along the chain segment direction is retained. The wind speed in the opposite direction or deviating from the chain segment direction is not used as the current chain segment transmission speed. Finally, the chain-direction wind speed components in the transmission corridor and during the relay period are averaged to obtain the average wind speed along the chain direction from city A to city B and from city B to city C.

[0012] After obtaining the chain segment distance and the average wind speed along the chain direction, the system divides the chain segment distance by the average wind speed along the chain direction to obtain the transmission time from city A to city B and the transmission time from city B to city C. The two transmission times are then used to calculate the transmission time difference between cities. The intercity transmission time difference Td is obtained using the following formula: .

[0013] Preferably, the relay strength assessment unit combines the intercity transmission time difference Td with the initiation code feature set QF to generate the candidate chain assessment quantity E; The candidate chain evaluation value E is obtained using the following formula: ; In the formula, E specifically represents the candidate chain. The initial evaluation results.

[0014] The smaller the intercity transmission time difference Td, the better. The timing of the start-up, HCHO takeover, and ozone peak is more closely aligned with the cross-city relay process; Preferably, the chain source code generation module includes a ternary code equalization parsing unit and a relay chain source code generation unit; The ternary code equalization parsing unit is based on the starting code feature set QF and reads... Initiation code B1, VOC successor code B2, and receptor hysteresis code B3, when Initiator code B1, VOC successor code B2, and receptor hysteresis code B3 belong to the same candidate chain. At that time, the balance degree G of the ternary code is calculated and obtained; The ternary code balance G is obtained using the following formula: ; In the formula, This represents the minimum code value among the three codes in the current candidate chain. This represents the maximum code value among the three codes in the current candidate chain, and bg represents a very small positive number with a value of 0.001. The relay chain source code generation unit combines the candidate chain evaluation quantity E and the ternary code balance degree G to calculate and obtain the relay chain source code Cs; The relay chain source code Cs is obtained by multiplying the candidate chain evaluation quantity E and the ternary code balance degree G.

[0015] The current relay chain source code Cs is a single-chain output for tracing ozone precursors from satellite remote sensing in urban agglomerations, used to represent candidate chains. The degree of relay closure; If the candidate chain evaluation value E is high but B1, B2, and B3 differ significantly, it indicates that the current chain may be supported by a single high value, and the ternary code balance G will make the relay chain source code Cs smaller; if B1, B2, and B3 are relatively balanced, but the transmission time difference is large, then the candidate chain evaluation value E will make the relay chain source code Cs smaller. Preferably, the traceability output module includes a chain-based percentage calculation unit and a chain segment result output unit; The chain-based percentage calculation unit is based on the relay chain source code Cs and reads candidate chains. And calculate the chain ratio of each candidate chain. ; Chain proportion of candidate chains Obtain it using the following formula: ; In the formula, Specifically, it represents the chain proportion of the q-th candidate chain. This represents the relay chain source code for the q-th candidate chain, where n represents the total number of candidate chains in the current contamination process. According to the chain proportion of candidate chains The candidate chains are sorted from largest to smallest by their numerical values, and the sorting result is output as the chain segment result.

[0016] Preferably, the chain segment result output unit generates, based on the chain segment result, Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments; The chain proportion of candidate chains The candidate chain ranked first is taken as the first relay chain. City A, City B, and City C in the first relay chain are read and output as follows: Starting cities, VOC relay cities, and ozone receptor cities; in, The starting city is generated from the first relay chain. The city with starting code B1, the VOC relay city originates from the city that generates VOC relay code B2 in the first relay chain, and the ozone receptor city originates from the city that generates receptor lag code B3 in the first relay chain. Reading the first relay chain The minimum value among the start code B1, VOC successor code B2, and receptor hysteresis code B3 is used as the basis for chain break verification. When the minimum value is When starting code B1, output The startup verification segment checks the following: Start the city's morning Positive outliers Morning delivery volume from the starting city to the VOC relay city Start the proportion of land used for urban roads; When the minimum value is VOC succession code B2, output a VOC succession verification segment. The verification content includes: the positive growth of afternoon HCHO in the VOC succession city, and the land use carrying capacity of the VOC succession city. The amount of material delivered between the starting city and the VOC relay city during the intermediate period; When the minimum value is receptor hysteresis code B3, an ozone receptor verification fragment is output. The verification content includes: the evening ozone positive growth amount of the ozone receptor city, the afternoon transport overlap amount from the VOC relay city to the ozone receptor city, and the time continuity factor from the VOC relay city to the ozone receptor city.

[0017] A satellite remote sensing method for tracing ozone precursors in urban agglomerations includes the following steps: Step 1: Analyze continuous multi-temporal phases of urban agglomerations using the scene temporal sampling module. Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, to obtain a set of start-up scenario values; Step 2: The relay ternary code generation module generates the code based on the starting scenario value set. The initiation code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; Step 3: The candidate chain preliminary evaluation module generates the candidate chain evaluation quantity E based on the starting code feature set QF and the inter-city transmission time difference Td; Step 4: The chain source code generation module generates the relay chain source code Cs based on the candidate chain evaluation quantity E and the ternary code balance degree G. Step 5: The traceability output module generates the chain proportion based on the Cs source code of each relay chain and outputs it. Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments.

[0018] This invention provides a satellite remote sensing method and system for tracing ozone precursors in urban agglomerations, which has the following advantages: (1) During system operation, the chain source code generation module generates relay chain source code Cs based on the candidate chain evaluation quantity E and the ternary code balance degree G. Then, the traceability output module generates the chain proportion based on each relay chain source code Cs, which can output the chain proportion. The system identifies starting cities, VOC relay cities, ozone receptor cities, and segments requiring chain disruption verification. The current output not only provides the pollution chain sequence but also pinpoints specific segments within the chain that need verification, enabling city clusters to coordinate prevention and control efforts around the morning's events. Verification was conducted at the starting point, the afternoon VOC relay point, and the evening ozone receptor point to address the problem that existing source tracing results were insufficient to form a chain of treatment guidelines.

[0019] (2) By incorporating city location vectors and temporal wind vectors into the scene time-series sampling process through intercity transport, the starting scene value reflects not only the concentration changes within the city itself, but also the current wind field's support for intercity precursor transport. Therefore, the subsequently generated morning... The starting scenario value, the afternoon HCHO receiving scenario value, and the evening ozone receptor scenario value all contain inter-city transmission information, which can express the continuous process of emissions from upwind cities, receiving from intermediate cities, and receiving from downwind cities in urban agglomerations, thus improving the problem that fixed administrative regions or fixed grids are difficult to reflect cross-city transmission.

[0020] (3) By retrieving afternoon HCHO acceptor scene values ​​along the downwind direction from morning to noon in city A, and retrieving evening ozone acceptor scene values ​​along the downwind direction from afternoon to evening in city B, the formation of the candidate chain can be constrained by both temporal order and wind field transport. Current processing avoids combining spatially dispersed and temporally discontinuous data. HCHO and ozone fragments are forcibly combined into a source tracing chain, and ozone receptor cities lacking HCHO receiving scenarios are retained as isolated receptor fragments, not entering the complete candidate chain, reducing the possibility of mistakenly classifying receptor cities as the end of the complete pollution chain.

[0021] (4) Read the same candidate chain through the ternary code equalization parsing unit The starting code B1, VOC relay code B2, and receptor hysteresis code B3 generate a ternary code balance G. The relay chain source code generation unit then combines the candidate chain evaluation value E with the ternary code balance G to obtain the relay chain source code Cs. This process ensures that the final source code depends not only on the overall strength of the candidate chain but also on the balance of the three relay codes, reducing the dominance of single city, single time period, or single pollutant values ​​on the source tracing results. The relay chain source code Cs serves as the input for subsequent chain proportion calculations, supporting the output... The data on starting cities, VOC relay cities, ozone receptor cities, and chain-breaking verification segments provide a chain-based data basis for joint prevention and control in urban clusters. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the block flow of a satellite remote sensing ozone precursor tracing system for urban agglomerations according to the present invention. Figure 2 This is a schematic diagram illustrating the steps of a satellite remote sensing method for tracing ozone precursors in urban agglomerations according to the present invention. Figure 3 This is a schematic diagram of the candidate chain binding judgment process of the present invention; Figure 4 This is a schematic diagram of the chain breakage check output judgment process of the present invention. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] Example 1 This invention provides a satellite remote sensing ozone precursor tracing system for urban clusters. Please refer to [link / reference]. Figures 1 to 4 It includes a scene time-series sampling module, a relay ternary code generation module, a candidate chain preliminary evaluation module, a chain source code generation module, and a traceability output module; Scene time-series sampling module analyzes continuous multi-temporal phases of urban agglomerations Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, to obtain a set of start-up scenario values; The relay ternary code generation module generates the code based on the set of starting scenario values. The initiation code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; The candidate chain initial evaluation module generates the candidate chain evaluation quantity E based on the initiation code feature set QF and the inter-city transmission time difference Td; The chain source code generation module uses the candidate chain evaluation quantity E as a basis and combines the ternary code balance degree G to generate the relay chain source code Cs; The source tracing output module generates the chain proportion based on the Cs source code of each relay chain and outputs it. Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments.

[0025] In this embodiment, the scene temporal sampling module is used to sample continuous multi-temporal phases of the urban agglomeration. The system unifies the processing of column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary, and land use information, enabling the organization of scattered satellite remote sensing data, ground monitoring data, and urban spatial data into a set of starting scenario values. Compared to methods that rely solely on single-city concentrations or fixed grid concentrations for source tracing, the current system can integrate morning... By treating the start-up, afternoon HCHO absorption, and evening ozone receptor within the same pollution process, the analysis of ozone precursors in urban clusters is no longer limited to single-moment concentration distribution, but forms a scenario data foundation with a time sequence.

[0026] In this embodiment, the relay ternary code generation module converts the starting scenario value set into... The starting code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted into a starting code feature set QF, which can identify the upwind city. Anomalies, increases in HCHO levels in intermediate cities, and peak ozone levels in downwind cities were converted into initiation, relay, and acceptor data in a chain process, respectively. This contrasts with direct comparisons. By using methods such as HCHO or ozone concentration levels, the current system can express the different chain segments in which different cities play a role in ozone generation, reducing the attribution bias of directly treating ozone receptor cities as major emitting cities.

[0027] In this embodiment, the inter-city transmission time difference Td is introduced through the candidate chain preliminary evaluation module, and the candidate chain evaluation quantity E is generated by combining the starting code feature set QF. This can incorporate the wind field transmission time, The start-up time and ozone peak time are included in the same candidate chain analysis process. The current processing method can exclude candidate chains that are only adjacent in concentration but not closed in terms of transmission time, making the source tracing results of cross-city ozone precursors more consistent with the actual evolution process of "upwind start-up - intermediate reception - downwind receiver", and solving the problem that the fixed administrative boundary analysis in the existing technology is difficult to express the cross-city transmission time lag.

[0028] Example 2 Please refer to Figure 1 Specifically: the scene timing sampling module includes a multi-source scene normalization unit and a relay scene slicing unit; Multi-source scene unification unit receives continuous multi-temporal data from urban clusters Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, and organize data from different sources, time intervals and spatial scales into the same urban agglomeration spatiotemporal framework for unified spatiotemporal organization; First, analyze the coverage status of satellite pixels and city boundaries to obtain the coverage data for each city at each time point. HCHO area-weighted value; Every city at every moment The HCHO area-weighted value uses the coverage area of ​​each satellite pixel within the city boundary as the weight, and assigns weights to each pixel at the current time. The city-level results were obtained by weighted averaging of column concentrations and HCHO column concentrations. Column concentration values ​​and city-level HCHO column concentration values; Further analysis of the effect of boundary layer height on The effect of column concentration on near-surface expression, obtaining Startup base quantity HCHO's basic volume and basal amount of ozone receptors The formula is as follows: ; ; In the formula, This indicates that city i at time t Area-weighted column concentration, This represents the boundary layer height of city i at time t. This represents the area-weighted column concentration of HCHO in city i at time t. Baseline amount of ozone receptors The method for obtaining the ozone concentration is as follows: First, determine all ozone ground monitoring stations in city i that are involved in the calculation; then, obtain the ozone concentration of each station at time t and determine the representative weight of each station to city i; then, multiply the ozone concentration of each station by its representative weight to obtain the weighted contribution of each station to the basic amount of ozone receptors in the city; finally, sum the weighted contributions of all stations and divide by the sum of the representative weights of all stations to obtain the basic amount of ozone receptors in city i at time t. Analyze the degree of wind direction transport alignment from city i to city j to obtain the intercity transport volume. The formula is as follows: ; In the formula, Specifically, this represents the amount of material being transported from city i to city j at time t. This represents the spatial location vector of city i, taking the city's center point. This represents the spatial location vector of city j, taken as the city's center point. The wind vector at time t; Relay scene slicing unit based on intercity transport volume , Startup base quantity HCHO's basic volume and basal amount of ozone receptors Based on this, generate the morning The formulas for the starting scenario value, the afternoon HCHO catchment scenario value, and the evening ozone receptor scenario value are as follows: ; In the formula, Indicates the morning of city i Startup scene value, This indicates that city i is in the morning period. Start the basic quantity. This indicates that city i experiences similar weather conditions on the morning of the day. The baseline value for starting basic quantity, This represents the proportion of road land use in city i. This represents the amount of transported data from city i to city j during the morning session. ; In the formula, This represents the afternoon HCHO load factor for city j. This represents the baseline amount of HCHO absorbed by city j during the afternoon period. The baseline amount of HCHO absorbed by city J during the morning session. This represents the land use acceptance weight of city j. This represents the amount of transported data from city i to city j during the intermediate time period. ; In the formula, This represents the evening ozone receptor scene value for city k. This represents the baseline amount of ozone receptors in city k during the evening period. This represents the baseline amount of ozone receptors in city k during midday. This represents the amount of transported data from city j to city k during the afternoon period. This represents the time continuity factor from city j to city k; The morning will be obtained The starting scenario value, the afternoon HCHO receiving scenario value, and the evening ozone receptor scenario value were fitted to obtain the starting scenario value set.

[0029] In this embodiment, a multi-source scene normalization unit is used to normalize continuous multi-temporal phases. Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary, and land use information are compiled into the same spatiotemporal framework for the same urban cluster, enabling data from different observation sources to be calculated around the same city and the same time period. Through weighted processing of satellite pixels and urban boundary coverage area, city-level... Area-weighted column concentration and city-level HCHO area-weighted column concentration solve the problem that pollution information is difficult to classify into specific cities when satellite pixels cross city boundaries, thus forming a unified data foundation for subsequent inter-city force analysis.

[0030] In this embodiment, the boundary layer height is used to... Column concentration was used for near-ground expression treatment to obtain The starting baseline quantity is determined, and the area-weighted column concentration of HCHO is used as the baseline quantity for HCHO acceptance. The baseline quantity of ozone acceptors is obtained by weighting the ozone stations. The three data sources—HCHO, ozone, and HCl—form the foundational quantities that can participate in chained calculations. This processing reduces spatial scale discrepancies that arise when relying solely on satellite column concentrations or single-station ozone concentrations for assessment, making the morning ozone concentration data more accurate within urban clusters. The start-up, afternoon HCHO absorption, and evening ozone receptors can all be included in the same calculation process.

[0031] In this embodiment, the morning scene is generated by the relay scene slicing unit. The starting scenario value, the afternoon HCHO receiving scenario value, and the evening ozone receptor scenario value were used to fit the three types of scenario values ​​into a starting scenario value set, making the original The data on HCHO and ozone were transformed into a time-series relay scenario. This result can provide insights for subsequent... The generation of initiation codes, VOC relay codes, and receptor hysteresis codes provides input, enabling the system to identify pollution sources by no longer simply comparing pollution concentrations in a single city, but rather by focusing on the process of "morning initiation—afternoon relay—evening receptor." It initiates cities, VOC relay cities, and ozone receptor cities, and provides data support for the output of chain break verification segments.

[0032] Example 3 Please refer to Figure 3 Specifically: the relay ternary code generation module includes a link candidate binding unit and a ternary code fitting unit; The link candidate binding unit analyzes the morning session in the set of startup scenario values. Startup Scenario Value The city with the highest median score gains the upper hand. Start with candidate city A, then search for the afternoon HCHO carrying capacity value of city j along the downwind direction of city A from morning to noon. Cities with high median values ​​were selected as candidate cities for VOCs to take over; subsequently, ozone receptor values ​​for city k in the evening were retrieved along the downwind direction from city B from afternoon to evening. Cities with the highest median ozone concentrations are selected as candidate cities for ozone receptors (C). During the search process, the three cities were combined and ranked, and the candidate chains were bound together in chronological order by "morning start, afternoon takeover, evening recipient". ; When ozone in a certain city k is affected by the scene value at dusk When the ozone concentration exceeds the preset scene threshold, but there is a lack of afternoon HCHO carryover scene values ​​in the upwind direction of city j. In the case of receiving a candidate city, the current city is retained as an isolated receptor fragment and does not enter the complete candidate chain.

[0033] The ternary code fitting unit is based on the candidate chain. generate The initiation code B1, the VOC successor code B2, and the receptor hysteresis code B3 are fitted together to form the initiation code feature set QF. Start code B1 is obtained using the following formula: ; In the formula, This indicates the morning hours in city A. Start the basic quantity. This indicates that in city A, on similar weather days, the morning... The baseline value for starting basic quantity, Indicates the morning in city A Positive outliers This represents the average transport overlap from city A to city B during the morning period, where A represents upwind. The candidate cities for starting are: B represents the intermediate VOC relay candidate city, and C represents the downwind ozone receptor candidate city. VOC successor code B2 is obtained using the following formula: ; In the formula, This represents the baseline volume of HCHO absorbed by city B during the afternoon. This represents the baseline HCHO intake in City B during the morning session. This indicates a positive increase in HCHO levels in city B during the afternoon. This indicates the land use absorption weight of city B. This represents the average transport overlap from city A to city B during the intermediate period; The receptor hysteresis code B3 is obtained using the following formula: ; In the formula, This represents the baseline amount of ozone receptors in city C during the evening. This represents the baseline amount of ozone receptors in city C during midday. This indicates the positive increase in ozone levels in city C during the evening. This represents the average transport overlap from city B to city C during the afternoon period. This represents the time continuity factor from city B to city C.

[0034] In this embodiment, the link candidate binding unit will be used to bind the morning... The starting scenario value, the afternoon HCHO takeover scenario value, and the evening ozone receptor scenario value were bound in chronological order to form a candidate chain. Compared to sorting by pollution concentration in a single city, the current treatment method can include upstream areas. By incorporating candidate cities for initiation, intermediate VOC relay candidate cities, and downwind ozone receptor candidate cities into the same cross-city chain, the source tracing object shifts from the pollution level of a single city to the inter-city relay process, which facilitates the explanation of situations where ozone generation within urban agglomerations is not limited to the vicinity of emission points.

[0035] In this embodiment, the ternary code fitting unit generates respectively The start code B1, VOC successor code B2, and receptor hysteresis code B3 can transmit the morning signal of city A. Positive anomalies, the afternoon positive increase in HCHO in City B, and the evening positive increase in ozone in City C were combined with the average inter-city transport correlation, land use carrying capacity weight, and time carrying capacity factor, respectively, transforming the three pollution fragments into three types of relay codes within the same candidate chain. Compared to directly using... The original concentrations of HCHO or ozone, the current ternary code can express the roles of the three segments of "initiator, successor, and acceptor" in the same pollution process, reducing the problem of difficulty in direct comparison between different observed objects.

[0036] In this embodiment, by... The initiation code B1, VOC relay code B2, and receptor hysteresis code B3 are fitted into an initiation code feature set QF, which provides a unified input for the subsequent candidate chain preliminary evaluation module to calculate the inter-city transport time difference and candidate chain evaluation metrics. The current initiation code feature set QF retains the city role, time period role, and transport information for each candidate chain, enabling subsequent analysis to determine the continuity of cross-city pollution processes based on the same chain, rather than processing them separately. Abnormalities, HCHO growth, and ozone peaks, thus contributing to the output Establish a data foundation for starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments.

[0037] Example 4 Please refer to Figure 1 Specifically: the candidate chain preliminary evaluation module includes a transmission time difference resolution unit and a relay strength evaluation unit; Transmission Time Difference Resolution Unit (TTD) uses the starting code feature set QF and candidate chains. Based on; from The morning of start code B1 Extracting City A from Startup Records The start time tN is determined, and then the ozone peak time tO for city C is extracted from the ozone receptor record belonging to receptor hysteresis code B3. Analyze the spatial distances from city A to city B and from city B to city C, and the average wind speeds along the chain direction during the corresponding time periods, to obtain... Transmission time and Transmission time And calculate the inter-city transmission time difference Td; The intercity transmission time difference Td is obtained using the following formula: .

[0038] The relay strength assessment unit combines the intercity transmission time difference Td with the initiation code feature set QF to generate the candidate chain assessment quantity E; The candidate chain evaluation value E is obtained using the following formula: ; In the formula, E specifically represents the candidate chain. The initial evaluation results.

[0039] The chain source code generation module includes a ternary code equalization parsing unit and a relay chain source code generation unit; The ternary code equalization parsing unit is based on the starting code feature set QF and reads... Initiation code B1, VOC successor code B2, and receptor hysteresis code B3, when Initiator code B1, VOC successor code B2, and receptor hysteresis code B3 belong to the same candidate chain. At that time, the balance degree G of the ternary code is calculated and obtained; The ternary code balance G is obtained using the following formula: ; In the formula, This represents the minimum code value among the three codes in the current candidate chain. This represents the maximum code value among the three codes in the current candidate chain, and bg represents a very small positive number; The relay chain source code generation unit combines the candidate chain evaluation quantity E and the ternary code balance degree G to calculate and obtain the relay chain source code Cs; The relay chain source code Cs is obtained by multiplying the candidate chain evaluation quantity E and the ternary code balance degree G.

[0040] In this embodiment, the transmission time difference resolution unit is used to resolve the time difference from... The morning of start code B1 Extracting City A from Startup Records The start time tN is used, and the ozone peak time tO of city C is extracted from the ozone receptor record to which receptor hysteresis code B3 belongs, so that the initial evaluation of candidate chains is no longer based solely on... Instead of processing the values ​​of HCHO and ozone, this method incorporates the timing of the pollution event. Through this treatment, the morning pollution levels in City A can be controlled. The start-up, the afternoon VOC relay in City B, and the evening ozone receptor in City C are included in the same time chain, providing a time basis for identifying the cross-city relay process of precursors in urban agglomerations.

[0041] In this embodiment, the relay strength evaluation unit compares the intercity transmission time difference Td with the start code feature set QF. The initiation code B1, VOC relay code B2, and receptor hysteresis code B3 are combined to generate the candidate chain evaluation quantity E. The current candidate chain evaluation quantity simultaneously contains three relay codes and the transmission time difference, enabling city A to... The initial assessment of three segments—start-up, HCHO in city B, and ozone receptor in city C—is conducted using the same numerical values. Compared to methods that only count the concentration of a single city or a single precursor indicator, the current treatment can distinguish between city combinations with mismatched time periods and incomplete chain segments in the initial assessment, reducing the likelihood of outputting scattered pollution fragments as complete source tracing chains.

[0042] Example 5 Please refer to Figure 4 Specifically: the traceability output module includes a chain-based percentage calculation unit and a chain segment result output unit; The chain-based percentage calculation unit is based on the relay chain source code Cs and reads candidate chains. And calculate the chain ratio of each candidate chain. ; Chain proportion of candidate chains Obtain it using the following formula: ; In the formula, Specifically, it represents the chain proportion of the q-th candidate chain. This represents the relay chain source code for the q-th candidate chain, where n represents the total number of candidate chains in the current contamination process. According to the chain proportion of candidate chains The candidate chains are sorted from largest to smallest by their numerical values, and the sorting result is output as the chain segment result.

[0043] The chain segment result output unit generates, based on the chain segment result, Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments; The chain proportion of candidate chains The candidate chain ranked first is taken as the first relay chain. City A, City B, and City C in the first relay chain are read and output as follows: Starting cities, VOC relay cities, and ozone receptor cities; in, The starting city is generated from the first relay chain. The city with starting code B1, the VOC relay city originates from the city that generates VOC relay code B2 in the first relay chain, and the ozone receptor city originates from the city that generates receptor lag code B3 in the first relay chain. Reading the first relay chain The minimum value among the start code B1, VOC successor code B2, and receptor hysteresis code B3 is used as the basis for chain break verification. When the minimum value is When starting code B1, output The startup verification segment checks the following: Start the city's morning Positive outliers Morning delivery volume from the starting city to the VOC relay city Start the proportion of land used for urban roads; When the minimum value is VOC succession code B2, output a VOC succession verification segment. The verification content includes: the positive growth of afternoon HCHO in the VOC succession city, and the land use carrying capacity of the VOC succession city. The amount of material delivered between the starting city and the VOC relay city during the intermediate period; When the minimum value is receptor hysteresis code B3, an ozone receptor verification fragment is output. The verification content includes: the evening ozone positive growth amount of the ozone receptor city, the afternoon transport overlap amount from the VOC relay city to the ozone receptor city, and the time continuity factor from the VOC relay city to the ozone receptor city.

[0044] In this embodiment, the chain proportion calculation unit calculates the chain proportion based on the relay chain source code of each candidate chain, enabling different candidate chains to be compared in a uniform manner within the same contamination process. The relay chain source code has been generated from the candidate chain evaluation quantity and the ternary code balance, and includes... The information includes initiation, VOC relay, ozone receptors, and transmission time. Therefore, the chain proportion is no longer ranked based on the concentration of a single city, but on the source code proportion of the complete relay chain. This is helpful in distinguishing the relative roles of multiple cross-city relay chains in the same ozone pollution process.

[0045] In this embodiment, by arranging candidate chains according to their chain proportions and using the first-ranked candidate chain as the first relay chain, an output chain with chain continuity can be determined from multiple candidate city combinations. Currently, city A, city B, and city C in the first relay chain originate from the generated... The city of the starting code B1, VOC successor code B2, and receptor hysteresis code B3, therefore the output The starting cities, VOC relay cities, and ozone receptor cities all have clearly defined data sources. Compared to cities that directly emit large amounts of ozone, the current treatment can separately express upwind starting, mid-wind relay, and downwind receptor cities, reducing the attribution bias of equating ozone receptor cities with major emitting cities.

[0046] In this embodiment, by reading the first relay chain... The system uses three codes: initiation code B1, VOC relay code B2, and receptor hysteresis code B3. The minimum value among these three is used as the basis for chain break verification, allowing the identification of the segment requiring verification from within the first relay chain. When the minimum value originates from B1, the verification target is limited to... Start the city's morning Positive outliers The morning delivery volume from the starting city to the VOC relay city and The proportion of urban road land use is initiated; the minimum value originates from B2, and the verification objects are limited to the afternoon HCHO positive growth of VOC-receiving cities, the land use absorption weight of VOC-receiving cities, and... The transmission overlap between the starting city and the VOC relay city during the intermediate period; the minimum value is derived from B3, and the verification objects are limited to the evening ozone positive increase in the ozone recipient city, the afternoon transmission overlap between the VOC relay city and the ozone recipient city, and the time continuity factor between the VOC relay city and the ozone recipient city. This processing ensures that the chain break verification objects come from the code values ​​within the relay chain, without introducing new judgment data.

[0047] In this embodiment, the traceability output module ultimately forms the first relay chain, the chain proportion, and... By identifying initiating cities, VOC relay cities, ozone receptor cities, and broken chain verification segments, the source tracing results of ozone precursors in urban clusters are transformed from a single contribution ranking to a chain-segmented output. This output can correspond to "morning..." The pollution process, from "start-up—afternoon HCHO takeover—evening ozone receptor," provides a chain-based verification basis for joint prevention and control in urban clusters; in cities where local emissions are not significant but ozone concentrations rise, the first relay chain can be used to explain the upstream situation. The participation of initiating cities and intermediate VOC relay cities makes the cross-city pollution responsibility chain clearer.

[0048] Example 6 A satellite remote sensing method for tracing ozone precursors in urban agglomerations; please refer to [reference needed]. Figure 2 Specifically, it includes the following steps: Step 1: Analyze continuous multi-temporal phases of urban agglomerations using the scene temporal sampling module. Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, to obtain a set of start-up scenario values; Step 2: The relay ternary code generation module generates the code based on the starting scenario value set. The initiation code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; Step 3: The candidate chain preliminary evaluation module generates the candidate chain evaluation quantity E based on the starting code feature set QF and the inter-city transmission time difference Td; Step 4: The chain source code generation module generates the relay chain source code Cs based on the candidate chain evaluation quantity E and the ternary code balance degree G. Step 5: The traceability output module generates the chain proportion based on the Cs source code of each relay chain and outputs it. Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended technical solutions and their equivalents.

Claims

1. A satellite remote sensing ozone precursor tracing system for urban agglomerations, characterized in that: It includes a scene time-series sampling module, a relay ternary code generation module, a candidate chain preliminary evaluation module, a chain source code generation module, and a traceability output module; Scene time-series sampling module analyzes continuous multi-temporal phases of urban agglomerations Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, to obtain a set of start-up scenario values; The relay ternary code generation module generates the code based on the set of starting scenario values. The initiation code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; The candidate chain initial evaluation module generates the candidate chain evaluation quantity E based on the initiation code feature set QF and the inter-city transmission time difference Td; The chain source code generation module uses the candidate chain evaluation quantity E as a basis and combines the ternary code balance degree G to generate the relay chain source code Cs; The source tracing output module generates the chain proportion based on the Cs source code of each relay chain and outputs it. Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments.

2. The satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 1, characterized in that: The scene timing sampling module includes a multi-source scene normalization unit and a relay scene slicing unit; Multi-source scene unification unit receives continuous multi-temporal phases of urban agglomerations Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, and organize data from different sources, time intervals and spatial scales into the same urban agglomeration spatiotemporal framework for unified spatiotemporal organization; First, analyze the coverage status of satellite pixels and city boundaries to obtain the coverage data for each city at each time point. HCHO area-weighted value; Every city at every moment The HCHO area-weighted value uses the coverage area of ​​each satellite pixel within the city boundary as the weight, and assigns weights to each pixel at the current time. The city-level results were obtained by weighted averaging of column concentrations and HCHO column concentrations. Column concentration values ​​and city-level HCHO column concentration values; Further analysis of the effect of boundary layer height on The effect of column concentration on near-surface expression, obtaining Startup base quantity HCHO's basic capacity and basal amount of ozone receptors The formula is as follows: ； ； In the formula, This indicates that city i at time t Area-weighted column concentration, This represents the boundary layer height of city i at time t. This represents the area-weighted column concentration of HCHO in city i at time t. Baseline amount of ozone receptors The method for obtaining the ozone concentration is as follows: first, determine all ozone ground monitoring stations in city i that are involved in the calculation; then, obtain the ozone concentration of each station at time t, and determine the representative weight of each station in city i. The ozone concentration at each site was then multiplied by its representative weight to obtain the weighted contribution of each site to the baseline amount of ozone receptors in the city. Finally, the weighted contributions of all stations are summed and divided by the sum of the representative weights of all stations to obtain the basic amount of ozone receptors for city i at time t. Analyze the degree of wind direction transport alignment from city i to city j to obtain the intercity transport volume. The formula is as follows: ； In the formula, Specifically, this represents the amount of material being transported from city i to city j at time t. This represents the spatial location vector of city i, taking the city's center point. This represents the spatial location vector of city j, taken as the city's center point. The wind vector at time t; Relay scene slicing unit based on intercity transport volume , Startup base quantity HCHO's basic capacity and basal amount of ozone receptors Based on this, generate the morning The formulas for the starting scenario value, the afternoon HCHO catchment scenario value, and the evening ozone receptor scenario value are as follows: ； In the formula, Indicates the morning of city i Startup scene value, This indicates that city i is in the morning period. Start the basic quantity. This indicates that city i experiences similar weather conditions on the morning of the day. The baseline value for starting basic quantity, This represents the proportion of road land use in city i. This represents the amount of transported data from city i to city j during the morning session. ； In the formula, This represents the afternoon HCHO load factor for city j. This represents the baseline amount of HCHO absorbed by city j during the afternoon period. The baseline amount of HCHO absorbed by city J during the morning session. This represents the land use acceptance weight of city j. This represents the amount of transported data from city i to city j during the intermediate time period. ； In the formula, This represents the evening ozone receptor scene value for city k. This represents the baseline amount of ozone receptors in city k during the evening period. This represents the baseline amount of ozone receptors in city k during midday. This represents the amount of transported data from city j to city k during the afternoon period. This represents the time continuity factor from city j to city k; The morning will be obtained The starting scenario value, the afternoon HCHO receiving scenario value, and the evening ozone receptor scenario value were fitted to obtain the starting scenario value set.

3. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 2, characterized in that: The relay ternary code generation module includes a link candidate binding unit and a ternary code fitting unit; The link candidate binding unit analyzes the morning session from the set of startup scenario values. Startup Scenario Value The city with the highest median score gains the upper hand. Start with candidate city A, then search for the afternoon HCHO carrying capacity value of city j along the downwind direction of city A from morning to noon. Cities with high median values ​​were selected as candidate cities for VOCs to take over; subsequently, ozone receptor values ​​for city k in the evening were retrieved along the downwind direction from city B from afternoon to evening. Cities with the highest median ozone concentrations are selected as candidate cities for ozone receptors (C). During the search process, the three cities were combined and ranked, and the candidate chains were bound together in chronological order by "morning start, afternoon takeover, evening recipient". ; When ozone in a certain city k is affected by the scene value at dusk When the ozone concentration exceeds the preset scene threshold, but there is a lack of afternoon HCHO carryover scene values ​​in the upwind direction of city j. In the case of receiving a specific scenario, the current city is retained as an isolated receptor fragment and does not enter the complete candidate chain.

4. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 3, characterized in that: The ternary code fitting unit is based on the candidate chain. generate The initiation code B1, the VOC successor code B2, and the receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; Start code B1 is obtained using the following formula: ； In the formula, This indicates the morning hours in city A. Start the basic quantity. This indicates that in city A, on similar weather days, the morning... The baseline value for starting basic quantity, Indicates the morning in city A Positive outliers This represents the average transport overlap from city A to city B during the morning period, where A represents upwind. The candidate cities for starting are: B represents the intermediate VOC relay candidate city, and C represents the downwind ozone receptor candidate city. VOC successor code B2 is obtained using the following formula: ； In the formula, This indicates the baseline HCHO intake in City B during the afternoon. This represents the baseline HCHO intake in City B during the morning session. This indicates a positive increase in HCHO levels in city B during the afternoon. This indicates the land use absorption weight of city B. This represents the average transport overlap from city A to city B during the intermediate period; The receptor hysteresis code B3 is obtained using the following formula: ； In the formula, This represents the baseline amount of ozone receptors in city C during the evening. This represents the baseline amount of ozone receptors in city C during midday. This indicates the positive increase in ozone levels in city C during the evening. This represents the average transport overlap from city B to city C during the afternoon period. This represents the time continuity factor from city B to city C.

5. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 4, characterized in that: The candidate chain preliminary evaluation module includes a transmission time difference resolution unit and a relay strength evaluation unit; Transmission Time Difference Resolution Unit (TTD) uses the starting code feature set QF and candidate chains. Based on; from The morning of start code B1 Extracting City A from Startup Records The start time tN is determined, and then the ozone peak time tO for city C is extracted from the ozone receptor record belonging to receptor hysteresis code B3. Analyze the spatial distances from city A to city B and from city B to city C, and the average wind speeds along the chain direction during the corresponding time periods, to obtain... Transmission time and Transmission time And calculate the inter-city transmission time difference Td; The intercity transmission time difference Td is obtained using the following formula: 。 6. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 5, characterized in that: The relay strength assessment unit combines the intercity transmission time difference Td with the initiation code feature set QF to generate the candidate chain assessment quantity E; The candidate chain evaluation value E is obtained using the following formula: ； In the formula, E specifically represents the candidate chain. The initial evaluation results.

7. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 6, characterized in that: The chain source code generation module includes a ternary code equalization parsing unit and a relay chain source code generation unit; The ternary code equalization parsing unit is based on the starting code feature set QF and reads... Initiation code B1, VOC successor code B2, and receptor hysteresis code B3, when Initiator code B1, VOC successor code B2, and receptor hysteresis code B3 belong to the same candidate chain. At that time, the balance degree G of the ternary code is calculated and obtained; The ternary code balance G is obtained using the following formula: ； In the formula, This represents the minimum code value among the three codes in the current candidate chain. This represents the maximum code value among the three codes in the current candidate chain, and bg represents a very small positive number; The relay chain source code generation unit combines the candidate chain evaluation quantity E and the ternary code balance degree G to calculate and obtain the relay chain source code Cs; The relay chain source code Cs is obtained by multiplying the candidate chain evaluation quantity E and the ternary code balance degree G.

8. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 7, characterized in that: The traceability output module includes a chain-based percentage calculation unit and a chain segment result output unit; The chain-based percentage calculation unit is based on the relay chain source code Cs and reads candidate chains. And calculate the chain ratio of each candidate chain. ; Chain proportion of candidate chains Obtain it using the following formula: ； In the formula, Specifically, it represents the chain proportion of the q-th candidate chain. This represents the relay chain source code for the q-th candidate chain, where n represents the total number of candidate chains in the current contamination process. According to the chain proportion of candidate chains The candidate chains are sorted from largest to smallest by their numerical values, and the sorting result is output as the chain segment result.

9. A satellite remote sensing ozone precursor tracing system for urban agglomerations according to claim 8, characterized in that: The chain segment result output unit generates, based on the chain segment result, Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments; The chain proportion of candidate chains The candidate chain ranked first is taken as the first relay chain. City A, City B, and City C in the first relay chain are read and output as follows: Starting cities, VOC relay cities, and ozone receptor cities; in, The starting city is generated from the first relay chain. The city with starting code B1, the VOC relay city originates from the city that generates VOC relay code B2 in the first relay chain, and the ozone receptor city originates from the city that generates receptor lag code B3 in the first relay chain. Reading the first relay chain The minimum value among the start code B1, VOC successor code B2, and receptor hysteresis code B3 is used as the basis for chain break verification. When the minimum value is When starting code B1, output The startup verification segment checks the following: Start the city's morning Positive outliers Morning delivery volume from the starting city to the VOC relay city Start the proportion of land used for urban roads; When the minimum value is VOC succession code B2, output a VOC succession verification segment. The verification content includes: the positive growth of afternoon HCHO in the VOC succession city, and the land use carrying capacity of the VOC succession city. The amount of material delivered between the starting city and the VOC relay city during the intermediate period; When the minimum value is receptor hysteresis code B3, an ozone receptor verification fragment is output. The verification content includes: the evening ozone positive growth amount of the ozone receptor city, the afternoon transport overlap amount from the VOC relay city to the ozone receptor city, and the time continuity factor from the VOC relay city to the ozone receptor city.

10. A satellite remote sensing ozone precursor tracing method for urban agglomerations, applied to the satellite remote sensing ozone precursor tracing system for urban agglomerations as described in any one of claims 1 to 9, characterized in that: Includes the following steps: Step 1: Analyze continuous multi-temporal phases of urban agglomerations using the scene time-series sampling module. Column concentration, HCHO column concentration, ozone station concentration, boundary layer height, wind field, urban boundary and land use information, to obtain a set of start-up scenario values; Step 2: The relay ternary code generation module generates the code based on the starting scenario value set. The initiation code B1, VOC successor code B2, and receptor hysteresis code B3 are fitted together to form the initiation code feature set QF; Step 3: The candidate chain preliminary evaluation module generates the candidate chain evaluation quantity E based on the starting code feature set QF and the inter-city transmission time difference Td; Step 4: The chain source code generation module generates the relay chain source code Cs based on the candidate chain evaluation quantity E and the ternary code balance degree G. Step 5: The traceability output module generates the chain proportion based on the Cs source code of each relay chain and outputs it. Starting cities, VOC relay cities, ozone receptor cities, and chain break verification segments.

Images