Analysis of the use of NDWIgreen and NDWIred for inland water mapping in the Yellow River Basin using Landsat-8 OLI imagery

Abstract

ABSTRACTClear and green water bodies reflect more green light than red light, while brown water bodies reflect more red light than green light. It is thus believed that the normalized difference water indexes using the green band and infrared wavelengths (NDWIgreen) and the normalized difference water indexes using the red band and infrared wavelengths (NDWIred) would act differently in mapping inland water bodies with different colours. This study aims to evaluate the performance of NDWIgreen and NDWIred in mapping water bodies with different colours in the Yellow River Basin using the Landsat-8 Operational Land Imager (OLI) imagery. The results show that NDWIgreen and NDWIred achieve overall accuracy of 95.99–96.82% and 88.32–96.68% in clear water mapping, 95.58–96.35% and 93.50–94.60% in green water mapping, 88.12–92.63% and 90.08–93.10% in brown water mapping, respectively. It is shown that both NDWIgreen and NDWIred can serve the purpose of inland water mapping. Moreover, the comparative analysis suggests that NDWIgreen is more suitable for clear and green water mapping, while NDWIred is more adequate for brown water mapping.