Accurate extraction of surface water in complex environment based on Google Earth Engine and Sentinel-2.

Jianfeng Li,Huping Ye,Yulu Wei,Biao Peng,Bijeesh Kozhikkodan Veettil

doi:10.1371/journal.pone.0253209

Abstract

To realize the accurate extraction of surface water in complex environment, this study takes Sri Lanka as the study area owing to the complex geography and various types of water bodies. Based on Google Earth engine and Sentinel-2 images, an automatic water extraction model in complex environment(AWECE) was developed. The accuracy of water extraction by AWECE, NDWI, MNDWI and the revised version of multi-spectral water index (MuWI-R) models was evaluated from visual interpretation and quantitative analysis. The results show that the AWECE model could significantly improve the accuracy of water extraction in complex environment, with an overall accuracy of 97.16%, and an extremely low omission error (0.74%) and commission error (2.35%). The AEWCE model could effectively avoid the influence of cloud shadow, mountain shadow and paddy soil on water extraction accuracy. The model can be widely applied in cloudy, mountainous and other areas with complex environments, which has important practical significance for water resources investigation, monitoring and protection.

Highlights

With the rapid development of aerospace technology, remote sensing technology provides advanced methods for many fields such as resource survey, environmental monitoring, regional analysis, and global macro research [1,2,3]
Mountain shadow and cloud shadow mainly exist in the study area, which affect the accuracy of water extraction
A fully automated water extraction model in complex environment (AWECE) based on Google Earth Engine and Sentinel-2 images was built through this study

Summary

Introduction

With the rapid development of aerospace technology, remote sensing technology provides advanced methods for many fields such as resource survey, environmental monitoring, regional analysis, and global macro research [1,2,3]. Accurate extraction of water information from remote sensing images is of great significance to watershed planning and investigation, monitoring and protection of water resources [4, 5]. Sri Lanka has emerged as a maritime hub connecting Asia-Africa-Europe shipping routes; this is of strategic, economic, and geopolitical significance to the country. The water environment of the island is complex and includes many types of water bodies, such as lakes, reservoirs, pit-ponds, lagoons and rivers. Sri Lanka is a tropical region, resulting in earth.

Methods

Results

Discussion

Conclusion