Selected Results Obtained with DLR’s Airborne EnMAP Demonstrator

C. Köhler, M. Bachmann, A. Baumgartner, S. Holzwarth, B. Pflug, M. Schneider

WHISPERS 2021 | C. H. Koehler et al. | 2021-03-24DLR.de • Chart 1

Optical Airborne Remote Sensing

(OpAiRS)

Collaboration across departments of the DLR Earth

Observation Center in Oberpfaffenhofen

ISO 9001 certified user service since 2007

We acquire airborne imaging spectroscopy data to support

DLR scientists and their associates in

• developing novel remote sensing applications

• preparing upcoming satellite missions

• validating data of spaceborne imaging spectrometers

Strong focus on data quality, instrument characterisation &

calibration

We perform usually 1-2 campaigns per year with 5-10

surveys per campaign

WHISPERS 2021 | C. H. Koehler et al. | 2021-03-24DLR.de • Chart 2

Camarena

Sailershausen

www.dlr.de/opairs

Mecklenburg

OpAiRS HySpex Surveys in 2020

Sensors and Calibration Facilities

DLR EnMAP Simulator since 2012: HySpex VNIR-1600 +

SWIR-320m-e on DLR Cessna Grand Caravan and Dornier 228

HySpex VNIR-3000N & SWIR-384 currently in commissioning phase

Calibration Laboratory partly funded by ESA as Calibration Home

Base (CHB) for ESA’s Airborne PRISM Experiment (APEX)

Current setups for geometric, spectral & radiometric characterisation

including linearity, stray light & temperature dependence

Traceable to national standards (PTB, NIST)

Used for the development of improved Level 1 products

(measurement techniques & algorithms)

WHISPERS 2021 | C. H. Koehler et al. | 2021-03-24DLR.de • Chart 3

Baumgartner, Andreas and Köhler, Claas H. (2020)Transformation of point spread functions on an individual pixel scale.Optics Express, 28 (26), DOI: 10.1364/oe.409626

DESIS Validation at CHIME Preparation Site Camarena (Spain)

Airborne & in-situ reflectance measurements for the validation of

• L2A product (BOA surface reflectance)

• L1 product (radiometric calibration) by simulation of TOA at-sensor radiance

• Higher-level products such as Cover% (fCover) or Soil Organic Matter

DESIS scene HySpex flight line

August 2020

WHISPERS 2021 | C. H. Koehler et al. | 2021-03-24DLR.de • Chart 4

EnMAP Preparation at University Forest Sailershausen (Germany)

Airborne and ground based spectroscopic measurements in 2018 & 2020 to investigate

drought stress effects on different tree species

Additionally regular scientific activities for research and education are organized by Julius-

Maximilians-Universität of Würzburg (JMU)

JMU established patches to study multidiversity and multifunctionality in production forests

→ monitoring since 2018

Forest health classification Ground based measurements HySpex false color RGB

WHISPERS 2021 | C. H. Koehler et al. | 2021-03-24DLR.de • Chart 5

Sentinel-2 Validation at Mecklenburg Lake District (Germany)

WHISPERS 2021 | C. H. Koehler et al. | 2021-03-24DLR.de • Chart 6

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Lake Stechlin 2018 MCS

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Meadow 2018 SVC

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Airborne and ground based spectroscopic measurements over land and water in May 2018

Validation of the Sentinel-2 L2A product (BOA surface reflectance)