Remote Sensing of Chlorophyll Fluorescence by the Airborne Plant Fluorescence Sensor (APFS)

Wednesday, 17 December 2014
John Boldt1, Jeng-Hwa Yee1, William B Cook2, Frank Morgan II3, Robert Demajistre4, Bruce D Cook5 and Lawrence A Corp6, (1)Applied Physics Laboratory Johns Hopkins, Laurel, MD, United States, (2)NASA Goddard SFC, Greenbelt, MD, United States, (3)JHU Applied Physics Lab, Laurel, MD, United States, (4)JHU/APL, Laurel, MD, United States, (5)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (6)Sigma Space Corporation, Lanham, MD, United States
Solar-induced chlorophyll fluorescence (ChlF) by terrestrial vegetation is linked closely to photosynthetic efficiency that can be exploited to monitor the plant health status and to assess the terrestrial carbon budget from space. The weak, broad continuum ChlF signal can be detected from the amount of fill-in of strong O2 absorption lines or Fraunhofer lines in the reflected solar spectral radiation. The Johns Hopkins University, Applied Physics Laboratory (JHU/APL) Airborne Plant Fluorescence Sensor (APFS) is designed and constructed specifically for airborne and groundbased ChlF measurements using the line fill-in ChlF measurement technique. In this paper, we will present the design of this triple etalon Fabry-Perot imaging instrument and the results of its vegetation fluorescence measurements obtained from the ground in the laboratory and from a NASA Langley King Air during our 2014 airborne campaign over vegetated targets in North Carolina and Virginia.