NASA’s Coastal and Ocean Airborne Science Testbed (COAST) L. Guild 1 *, J. Dungan 1, M. Edwards 1, P. Russell 1, S. Hooker 2, J. Myers 3, J. Morrow 4,

NASA’s Coastal and Ocean NASA’s Coastal and Ocean Airborne Science Testbed Airborne Science Testbed

(COAST)(COAST)L. Guild1*, J. Dungan1, M. Edwards1, P. Russell1, S.

Hooker2, J. Myers3, J. Morrow4, S. Dunagan1, P. Zell1, R.

Berthold1, and C. Smith1

1NASA Ames Research Center, Moffett Field, CA, USA 2NASA Goddard Space Flight Center, MD, USA

3Univ. of Calif., Santa Cruz/NASA Ames, Moffett Field, CA

4Biospherical Instruments Inc., San Diego, CA, USA

COAST ObjectivesCOAST Objectives

• Develop and integrate the first end-to-end instrument suite for simultaneous measurements of ocean color (modified imaging spectrometer), aerosol optical depth and water vapor column content (sunphotometer), and water bio-optical measurements (microradiometer-based multiwavelength radiometer package) using inputs from an associated precision navigation system.

• Advance calibration and validation (cal/val) of satellite ocean color through airborne campaigns of the COAST instrument suite flown in conjunction with satellites and in conjunction with in situ ship-based cal/val measurements and moorings.

• Produce high spatial resolution (5-10 m), atmospherically corrected and geolocated ocean-color products (calibrated to at-sensor radiance) that will advance understanding of coastal freshwater and marine processes and productivity and improve coastal models.

Needs: Research capability to address the challenges of remote sensing in the optically complex coastal environment, currently unachievable using satellite resources

Nov 17, 2010

Remote Sensing in the Optically Complex Coastal Zone• Airborne remote sensing is used to infer properties of the coastal zone.• High spatial resolution is needed to capture high spatial heterogeneity.

Airborne reflectance spectra are composites of reflectance from:1) the atmosphere (particles, gases); 2) the sea surface; 3) the water column (water molecules, phytoplankton, colored dissolved organic matter); and 4) the bottom (sediments, seagrass, corals).

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COAST Mission OverviewCOAST Mission Overview

Headwall Ocean Color Headwall Ocean Color Imaging SpectrometerImaging Spectrometer

Spectrometer: Concentric Pushbroom (Offner-type)Spectral Range: 380 – 760nm* = 10 nm (@ off-chip binning of 1.5nm pixels)Bands: 40*Spatial Elements: 700IFOV: 1.23 mradFOV: 46.7 degreesWeight: 20+ lbs; Power: 30 Watts

Array: 1600 x 1200 pixels (7.4m) @ -30CGrating optimized at 450 nmSpectral Smile: <0.25 Pixel (0.625nm)Keystone: <0.9 pixel (6.6m)Dispersion: 100 nm/mm, linear to <0.5%**

* No order-sorting ** Modeled values

MeasuresMeasures: Solar direct-beam : Solar direct-beam transmission, T, at 14 transmission, T, at 14 wavelengths,wavelengths,=354-2139 nm=354-2139 nm

Data productsData products Aerosol optical depth (AOD) at Aerosol optical depth (AOD) at

13 13 , 354-2139 nm*, 354-2139 nm* Water vapor column content Water vapor column content Ozone column content**Ozone column content** Aerosol extinction, Aerosol extinction,

354-2139 nm354-2139 nm Water vapor Water vapor

densitydensity*+ 3-parameter fit (useful for interpolating)*+ 3-parameter fit (useful for interpolating)

****Requires low sun, AOD(600 nm)<~0.03Requires low sun, AOD(600 nm)<~0.03

14-channel Ames Airborne 14-channel Ames Airborne Tracking Sunphotometer (AATS-Tracking Sunphotometer (AATS-14)14)

Monterey Bay Flight PlanningMonterey Bay Flight Planning

Alt = 6000 ft 5 m GSR

Alt = 4500 ft 4 m GSR

Alt = 12,000 ft 8 m GSR(Max alt w/o O2)

Alt = 100 ft (Lowest safe aircraft alt.)(Any speed okay)

AATS-14Microradiometers

AATS-14

HeadwallAATS-14Microradiometers

HeadwallAATS-14Microradiometers

Monterey Bay Flight Monterey Bay Flight PlanningPlanning

Flight line orientation optimized to avoid sunglint

Science Data PlanScience Data Plan

Scientific OutcomesScientific Outcomes

• A flight-tested instrument suite suitable for cal/val activities for future satellite missions, as well as currently operating and developing missions.

• Advanced payload capabilities for airborne carrier platforms including UASs.

• A multi-sensor ocean/atmosphere data set available for improved atmospheric calibration and in-water algorithms.

• Methodologies for empirical atmospheric correction developed for future airborne imagers of this type (e.g., NASA PRISM) when they come online.

• Methods to address the biological properties of important coastal zone ecosystems.

• Enabling technology for a broad range of research activities in the coastal zone to support the scientific community’s research goals and objectives.

Contact: [email protected]