基于深度神经网络的北印度洋叶绿素a剖面重建方法

Vertical Chlorophyll-a Profile Reconstruction in the North Indian Ocean Using Deep Neural Networks

  • 摘要: 为了深入理解海洋初级生产力分布格局、服务海洋生态环境变化监测,本文通过融合生物地球化学浮标(Biogeochemical-Argo, BGC-Argo)数据和卫星遥感数据,构建了深度学习模型以获取北印度洋叶绿素a(Chlorophyll-a, Chl-a)质量浓度的垂直分布特征。该模型将1DCNN-Transformer模块提取的BGC-Argo温度和盐度垂直剖面特征和Embedding模块转化的时空信息连续向量,与卫星遥感数据进行融合,输入深度神经网络(Deep Neural Network, DNN),以实现北印度洋Chl-a质量浓度垂直分布的重建。通过敏感性分析确定,海表温度(Sea Surface Temperature, SST)、海表Chl-a质量浓度,以及温度和盐度垂直剖面数据为模型的最佳输入变量。研究结果显示,模型反演Chl-a质量浓度剖面的RMSE值为0.106 μg/L,R2值达0.81。在0~140 m深度范围内,Chl-a质量浓度反演的RMSE最高值约0.4 μg/L,而在140 m以深范围误差则显著降低。在空间分布上,阿拉伯海域的Chl-a质量浓度最大值(A)显著高于孟加拉湾和赤道附近海域;在时间变化上,阿拉伯海、孟加拉湾和赤道附近海域出现的A及其对应深度(Zmax)呈现季节性差异,但ZmaxA之间存在一定的负相关性。

     

    Abstract: To gain an in-depth understanding of the distribution patterns of marine primary productivity and support the monitoring of marine ecological environment changes, this paper integrates Biogeochemical-Argo (BGC-Argo) float data with satellite remote sensing data to construct a deep learning model for retrieving the vertical distribution characteristics of Chlorophyll-a (Chl-a) mass concentration in the North Indian Ocean. The model combines the vertical temperature and salinity profile features extracted by the 1DCNN-Transformer module, the spatiotemporal continuous vectors transformed by the Embedding module, and satellite remote sensing data, which are then fed into a Deep Neural Network (DNN) to reconstruct the vertical distribution of Chl-a mass concentration in the North Indian Ocean. Sensitivity analysis identified Sea Surface Temperature (SST), sea surface Chl-a mass concentration, and vertical temperature and salinity profiles as the optimal input variables for the model. The results show that the model achieves an RMSE of 0.106 μg/L and an R2 of 0.81 in reconstructing Chl-a mass concentration profiles. Within the 0-140 m depth range, the maximum RMSE for Chl-a concentration retrieval is approximately 0.4 μg/L, while errors decrease significantly below 140 m. In terms of spatial distribution, the maximum Chl-a concentration (A) in the Arabian Sea is significantly higher than that in the Bay of Bengal and equatorial regions. In terms of temporal variation, the A values and their corresponding depths (Zmax) in the Arabian Sea, Bay of Bengal, and equatorial regions exhibit seasonal variations, with a certain negative correlation observed between Zmax and A.

     

/

返回文章
返回