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CN-122020569-A - Volcanic eruption monitoring method integrating wind cloud satellite and COSIC ionosphere occultation data

CN122020569ACN 122020569 ACN122020569 ACN 122020569ACN-122020569-A

Abstract

The invention discloses a volcanic eruption monitoring method for integrating wind cloud satellites and COSIC ionosphere occultation data, which comprises the steps of firstly collecting and preprocessing data, carrying out spherical harmonic function fitting on the preprocessed data, inverting to obtain the vertical total electron content of each grid point, defining an abnormal state and a normal state according to solar radiation flux indexes under grids to obtain a dynamic threshold of the abnormal state and a dynamic threshold of the normal state, collecting real-time data, carrying out inversion to obtain a real-time value of the vertical total electron content of a global grid, judging to be a suspected abnormal disturbance signal, recording relevant space-time information, extracting the vertical total electron content data of a preset area in a time window corresponding to the suspected abnormal disturbance signal, calculating the grid ratio according to conditions, judging to be solar or geomagnetic activity disturbance according to the ratio, and judging to be local volcanic eruption otherwise. The method can realize volcanic eruption monitoring with high efficiency, high speed, global coverage and high accuracy, and provides timely and reliable decision support for disaster prevention and reduction departments.

Inventors

  • BAI SONG
  • DONG MAN
  • LU DAO
  • SU MINGKUN
  • He shihang
  • LI ZHAO
  • HU SHUNQIANG
  • HE XIAOXING
  • Tan qidong
  • ZHANG HUIXIN

Assignees

  • 杭州电子科技大学

Dates

Publication Date
20260512
Application Date
20260410

Claims (15)

  1. 1. A volcanic eruption monitoring method integrating wind cloud satellite and COSIC ionosphere occultation data is characterized by comprising the following steps: step 1, gridding the world and marking grids containing active volcanoes and dormant volcanoes, collecting COSIC-1 and wind cloud-3C satellite ionosphere occultation historical data of volcanic eruption periods without VEI4 level or above, removing abnormal data after preprocessing the data, fitting the preprocessed data through spherical harmonic functions, and inverting to obtain the vertical total electron content of each grid point; step 2, defining an abnormal state and a normal state according to solar radiation flux indexes under grids, and obtaining a dynamic threshold value of the abnormal state and a dynamic threshold value of the normal state by calculating standard deviation of change rate of vertical total electron content per hour of each grid point under the two states; Step 3, acquiring ionosphere occultation data of the wind cloud-3D to wind cloud-3G satellites and the COSIC-2 satellites in real time, preprocessing and fitting spherical harmonic functions, inverting to obtain a real-time value of the vertical total electron content of the global grids, calculating the change rate of the vertical total electron content of each grid per hour at the data updating frequency of 60 minutes/time, judging suspected abnormal disturbance signals and recording relevant space-time information if the change rate exceeds a normal state dynamic threshold value and the grids are marked volcanic area grids; Step 4, extracting vertical total electron content data of a preset area in a time window corresponding to a suspected abnormal disturbance signal, constructing a vertical total electron content space area of grids in the preset area by adopting a kriging interpolation algorithm, calculating an integral disturbance index and a super-threshold grid duty ratio in the time window according to the vertical total electron content space area, judging that solar or geomagnetic activity is disturbed according to the duty ratio, and otherwise judging that local volcanic eruption is caused; And 5, supplementing the volcanic eruption event data and the corresponding ionosphere observation data which are collected and verified in practice to a historical database, and updating the dynamic threshold.
  2. 2. The method according to claim 1, wherein in step 1, the global area is divided into 1 degree x 1 degree grids and grids containing the active volcanic and the dormant volcanic are marked during the gridding process.
  3. 3. The method of claim 2, wherein in step 1, the preprocessing includes determining the quality of the electron profile and rejecting outlier data based on an average deviation and a noise level factor, wherein the average deviation of the effective electron density profile is 0-1.5 and the noise level factor is less than 0.01.
  4. 4. The method according to claim 2, wherein in the step 1, the calculation method of the vertical total electron content is that the electron density profile in the preprocessed ionosphere occultation data is interpolated according to a height spline, the electron density value in the height interval of 110-750km is integrated to obtain the oblique total electron content, the oblique total electron content is converted into vertical total electron content scattered points through a mapping function, and the vertical total electron content scattered points are fitted through a spherical harmonic function to obtain the vertical total electron content of a grid of 1 degree x 1 degree.
  5. 5. The method of claim 4, wherein the mapping function is a cosine value of a zenith angle of the puncture site multiplied by a total diagonal electron content.
  6. 6. The method according to claim 1, wherein in the step 2, a date that the solar radiation flux index is not less than 150sfu and the geomagnetic index average value is not less than 4 is defined as an ionospheric abnormal state, and the rest is a normal state.
  7. 7. The method according to claim 1, wherein in the step 2, the rate of change of the vertical total electron content per hour is the vertical total electron content of the grid at the present moment minus the vertical total electron content of the grid for the previous hour, divided by the time interval of 1 hour.
  8. 8. The method according to claim 1, wherein in the step 4, the preset area is set to be an area with latitude equal to or greater than 60 ° N and equal to or less than 60 ° S in a time window corresponding to the suspected abnormal disturbance signal.
  9. 9. The method according to claim 1, wherein in the step 4, the kriging interpolation algorithm is a common kriging interpolation method, a hysteresis distance of interpolation is set to 110km, a search radius is set to 1100km, and a spherical model is used to fit the experimental semi-variation function.
  10. 10. The method according to claim 1, wherein in the step 4, if the overall disturbance index of the region is greater than three times the average disturbance index of the spatial region of the vertical total electron content in the normal state and the super-threshold grid ratio exceeds 30%, it is determined that the solar or geomagnetic activity is disturbed, otherwise it is determined that the local volcanic eruption is generated.
  11. 11. The method according to claim 1, wherein in the step 4, the area global disturbance index is a sum of absolute values of change rates of vertical total electron contents of each grid in the vertical total electron content space area divided by a total grid number of the area.
  12. 12. The method according to claim 1, wherein in the step 4, the super-threshold grid ratio is the number of grids in the vertical total electron content space region, the change rate of the vertical total electron content exceeds the dynamic threshold of the abnormal state, and the number of grids in the vertical total electron content space region is proportional to the total number of grids in the region.
  13. 13. The method of claim 1, wherein in step 1, the volcanic-related location and burst data are obtained from a smini society global volcanic activity planning database, and the occultation data are obtained from a cloud of wind satellite remote sensing data service network and a COSMIC data storage center network.
  14. 14. The method according to claim 1, wherein in the steps 1 and 3, the spherical harmonic function adopts 15 th order 15 times, and the spherical harmonic coefficient is solved by a least square method, so as to fit the global grid point VTEC.
  15. 15. The method according to claim 1, wherein in the step 2, the abnormal state dynamic threshold and the normal state dynamic threshold are the sum of each grid change rate in the corresponding state and three times of standard deviation thereof.

Description

Volcanic eruption monitoring method integrating wind cloud satellite and COSIC ionosphere occultation data Technical Field The invention relates to the technical field of satellite remote sensing monitoring and disaster early warning, in particular to a volcanic eruption monitoring method integrating cloud satellite and COSIC ionosphere occultation data. Background Volcanic eruption is one of natural disasters with great influence on human life, has great influence on natural environment, and often the eruption of volcanic is accompanied with the occurrence of earthquake activities, which not only causes displacement of crust, but also affects ionosphere and high-level atmosphere. Volcanic eruption can cause a series of atmospheric pressure waves, and through exchanging energy with an ionized layer, the upper atmosphere above the earthquake is disturbed, so that the ionized layer disturbance is caused, and the normal operation of satellite navigation, communication and other systems is influenced. Data statistics show that there are approximately 50-70 volcanic eruptions per year worldwide, where strong eruption events can cause global ionospheric disturbances, severely impacting cross-regional communication and navigational positioning. Therefore, timely and accurate volcanic eruption monitoring can provide key support for disaster prevention, disaster reduction and the like, and personnel casualties and economic losses are reduced. The current method for monitoring volcanic eruption based on total electronic content (TEC, total Electron Content) of the ionized layer mainly utilizes total electronic content of a foundation GNSS to carry out time sequence analysis. Although the method has the advantage of high space-time resolution, the application efficiency of the method in volcanic eruption large-scale monitoring and quick response is limited to a certain extent because the quantity of the foundation GNSS observation data is huge and the complex multi-step data processing flow is involved, so that the whole processing time is long. Therefore, the volcanic eruption monitoring method with high efficiency, quick response, wide coverage and high space-time resolution is researched, provides powerful support for natural disaster monitoring departments, and is a hot spot and difficult problem to be solved currently. Disclosure of Invention The invention aims to overcome the defects of the prior art, provides a volcanic eruption monitoring method integrating cloud satellite and COSIC ionosphere occultation data, and solves the problems that the existing monitoring method based on a foundation GNSS is complex in data processing, time-consuming, difficult to realize global large-scale quick response, easy to be interfered by solar activity and geomagnetic activity, high in false alarm rate and the like. The method comprises the steps of fusing occultation data of a COSIC-1 satellite and a cloud-3C satellite, carrying out grid interpolation of 1 degree multiplied by 1 degree on the world by utilizing spherical harmonic function, combining geomagnetic index (Kp) and solar radiation flux (10.7 cm/2800MHz, F10.7) given by SEPC functional network as geomagnetic activity and solar activity intensity indexes, constructing a global ionosphere normal state background model and an ionosphere abnormal state background model, laying a reference for accurately extracting disturbance signals, calculating VTEC based on occultation data of the cloud-3D to the cloud-3G satellite and the COSIC-2, calculating the change rate in real time, realizing quick identification of the suspected disturbance signals by matching with a dynamic threshold, improving monitoring timeliness, modeling a space region VTEC of the vertical total electronic content above 60 degrees in north and south by utilizing a Kriging interpolation algorithm, accurately distinguishing disturbance of the volcanic activity and the geomagnetic activity by calculating the change rate and threshold value contrast analysis and region disturbance index analysis, and reducing the error rate. In conclusion, the volcanic eruption monitoring method aims to realize high-efficiency, rapid, global coverage and high-accuracy volcanic eruption monitoring and provide timely and reliable decision support for disaster prevention and reduction departments. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The invention provides a volcanic eruption monitoring method integrating wind cloud satellite and COSIC ionosphere occultation data, which comprises the following steps: step 1, gridding the world and marking grids containing active volcanoes and dormant volcanoes, collecting COSIC-1 and wind cloud-3C satellite ionosphere occultation historical data of volcanic eruption periods without VEI4 level or above, removing abnormal data after preprocessing the data, fitting the preprocessed data through spherical harmonic functions, and inver