PERSISTENT EFFECT OF 2015 EL NIÑO DROUGHT ON NIR REFLECTANCE OF CENTRAL AMAZON UPLAND FORESTS?

A Landsat 8 surface reflectance (SR) image of the Manaus region acquired 27 July 2016, seven months after the El Niño drought of 2015 ended, was compared to a pre-drought SR image (10 August 2015) and a recent SR image (28 July 2022), the latter two representing normal climate conditions. All three have similar DOY, similar solar elevation angles and fixed view angle for the area of interest – part of a large military reserve 35 km northeast of Manaus. The seven-month post-drought image shows lowered NIR reflectance of the forest canopy in all forest types, with greatest effect on well-drained oxisol plateaus with deep water table, suggesting persistent physiological damage to leaves or decreased upper canopy LAI. These patterns must still be corroborated using other Central Amazon scenes and sensors.