Toward Landsat and Sentinel-2 BRDF Normalization and Albedo Estimation: A Case Study in the Peruvian Amazon Forest

Frontiers in Digital Humanities

Franch, Belen¹  Roger, Jean-Claude¹  Villaescusa-Nadal, Jose Luis¹  Santamaria-Artigas, Andres²  Skakun, Sergii²  Vermote, Eric²  Masek, Jeff² 

[1] Department of Geographical Sciences, University of Maryland College Park, United States;NASA Goddard Space Flight Center, United States

关键词: Landsat 8;    Sentinel 2;    BRDF normalization;    Surface albedo;    Amazon;   

DOI  :  10.3389/feart.2018.00185

学科分类：社会科学、人文和艺术（综合）

来源: Frontiers

【 摘 要 】

The Amazon forest has been the focus of study by the science community during the last few decades. Remote sensing data analysis is the only way to study such a large geographical extent during an extended period of time. Since the launch in 2015 of Sentinel 2 and its increase in temporal resolution through the combination with Landsat sensors, a strong emphasis has been put on exploiting these data. Though these satellites provide near nadir observations, surface reflectance time series are affected by illumination variability throughout the year. These effects can be corrected using a Bidirectional Reflectance Distribution Function (BRDF) model. Franch et al. (2014a) developed a methodology to derive Landsat surface albedo and BRDF. It is based on the BRDF parameters from the MODerate Resolution Imaging Spectroradiometer (MODIS) which are disaggregated at Landsat spatial resolution (30 m). In this work, we apply the Franch et al. (2014a) method to normalize the surface reflectance for BRDF effects using the NASA’s Harmonized Landsat Sentinel-2 (HLS) product. We apply this method to the Tambopata region in Peru from 2013 to 2017 and validate it using ground-based albedometer measurements. The results show that the near infrared reflectance can increase up to 0.06 (20%) for low solar angles while the impact on the red range and the NDVI is minor (less than 0.01). The evaluation of the surface albedo against field measurements shows an error of 0.01.

【 授权许可】

CC BY