Research On The Reconstruction Algorithm Of Chlorophyll A Data From Remote Sensing Of The Yellow Sea And The Bohai Sea

Chlorophyll-a is an important indicator of eutrophication evaluation of water,it is the most important pigment for photosynthesis of phytoplankton,and it is also an important parameter for measuring its biomass.The monitoring of chlorophyll-a concentration on the sea surface by satellite remote sensing technology has the advantages of low cost,fast speed and large-scale synchronous measurement,and occupies an important position in marine ecological research and dynamic monitoring.Satellite remote sensing has become an effective way to obtain chlorophyll data on the sea surface.However,due to the influence of weather conditions,satellite sensor operation failure and other factors,there are a large number of irregular deletions in satellite remote sensing chlorophyll-a concentration data.Further use of the data is greatly limited.Therefore,the use of reasonable technical methods to reconstruct the chlorophyll remote sensing data set is of great significance for filling in the missing information and obtaining a high-quality and complete data set to expand the application breadth of remote sensing data and improve the utilization efficiency of remote sensing data.Aiming at the above problems,this paper first compares the reconstruction force of Data-Interpolating Convolutional Auto-Encoder(DINCAE)algorithm and Data Interpolating Empirical Orthogonal Functions(DINEOF)algorithm on chlorophyll data in the Yellow Sea and Bohai Sea,and analyzes the characteristics of the reconstruction results of the two algorithms.Finally,the dataset is applied according to the dominant algorithm,and the response mechanism of chlorophyll-a concentration to typhoon in the Yellow Sea and Bohai Sea is reconstructed by the DINCAE algorithm.The main contents of the full text are as follows(1)The data of chlorophyll-a concentration in the Yellow Sea and Bohai Sea were reconstructed by the DINCAE algorithm,and compared with the DINEOF algorithm,the reconstruction results were analyzed from the perspectives of reconstruction efficiency,reconstruction accuracy and adaptability of reconstructed data.It can be seen that the reconstruction results of the DINCAE algorithm retain more small-scale features,the reconstruction accuracy of the DINCAE algorithm is higher than that of the DINEOF algorithm,the reconstruction efficiency is 5 times that of the DINEOF algorithm,the error of the reconstructed dataset of different time scales is 0.6 lower than that of the DINEOF algorithm,and the data error of the reconstructed different spatial scales is 0.88 lower than that of the DINEOF algorithm.The reconstruction results of the DINEOF algorithm are smoother,and the stability of the reconstruction error of the DINEOF algorithm is better than that of the DINCAE algorithm.(2)The application analysis of the reconstructed dataset,applying the Yellow Sea chlorophylla concentration delay induced by typhoon "BAVI" in 2020 as an example,first compared with the performance of the results of the two algorithm reconfiguration results on this phenomenon,it can be seen that the results of the DINCAE algorithm are better than the DINEOF algorithm in the control of small-scale characteristics and numerical accuracy.The DINCAE algorithm was selected to reconstruct the reasons for the change of chlorophyll-a concentration in the sample area before and after hurricane transit.At the mouth of the Han River in Kwong Wa Bay,the upwelling caused by typhoons has altered the vertical temperature and salinity structure of the seawater,increasing the concentration of green pigments in the area.In the western waters of the Korean Peninsula,the wind pressure on the right side of the typhoon path can resonate with near-habitual oscillations when the hand rotates,causing strong vertical mixing,strong curling and strong upwelling processes,prompting the cold water rich in nutrients on the right side of the path to be transported to the upper ocean,inducing the proliferation of marine surface phytoplankton and increasing chlorophyll-a concentration.In the western waters off the Jeju Island,the geochannel generated by the typhoon's transit strengthened the area's original cold cyclone,giving it enough energy to bring rich nutrients from the subsurface,prompting an increase in chlorophyll-a concentrations.