Imaging the Coastal Ocean from Space

Transcription

1 Imaging the Coastal Ocean from Space Curtiss O. Davis College of Earth, Ocean and Atmospheric Sciences, University, Corvallis, OR, USA

2 HICO on the International Space Station The Hyperspectral Imager for the Coastal Ocean (HICO) What is hyperspectral imaging? How was HICO built? The International Space Station (ISS) opportunity The challenge of operating on the ISS What we can see with HICO? HICO data availability The future of Earth remote sensing on the ISS

3 What is Hyperspectral Imaging? A hyperspectral imager records a spectrum of the light from each pixel in the scene Hyperspectral image analysis exploits this extra spectral information Hyperspectral imager S = k i= 1 α E + N Spectrum for each pixel i i Spectral Decomposition for an open land scene Grass Dry Soil Leaves Minerals The imager design and method of exploitation must be tailored to the scene and the desired products.

4 Why do we need it? Multiple light paths Scattering due to: atmosphere aerosols water surface suspended particles bottom Absorption due to: atmosphere aerosols suspended particles dissolved matter Scattering and absorption are convolved The coastal ocean is an extremely complex region to image and we need hyperspectral imagery to resolve this complexity.

5 What is the Hyperspectral Imager for the Coastal Ocean (HICO)? HICO is an experiment to see what we gain by imaging the coastal ocean at higher spectral and spatial resolution from space. The HICO sensor: first spaceborne imaging spectrometer for coastal oceans samples coastal regions at <100 m (400 to 900 nm: at 5.7 nm) high signal-to-noise ratio to resolve the complexity of the coastal ocean Sponsored as an Innovative Naval Prototype (INP) by the Office of Naval Research: Goal to greatly reduce cost and shorten schedule. Start of Project to Sensor Delivery in 16 months Launched to the ISS September 10, 2009 HICO image of Hong Kong, October 2, HICO is integrated and flown under the direction of DoD s Space Test Program

6 HICO Flight Sensor - Stowed position spectrometer camera lens View port

7 HICO meets Performance Requirements Parameter Spectral Range Spectral Channel Width Number of Spectral Channels Signal-to-Noise Ratio for water-penetrating wavelengths Polarization Sensitivity Ground Sample Distance at Nadir Scene Size Cross-track pointing Scenes per orbit Performance 380 to 960 nm 5.7 nm 102 > 200 to 1 for 5% albedo scene (10 nm spectral binning) < 5% ( nm) 92 meters 42 x 192 km +45 to -30 deg 1 maximum Rationale All water-penetrating wavelengths plus Near Infrared for atmospheric correction Sufficient to resolve spectral features Derived from Spectral Range and Spectral Channel Width Provides adequate Signal to Noise Ratio after atmospheric removal Sensor response to be insensitive to polarization of light from scene Adequate for scale of selected coastal ocean features Large enough to capture the scale of coastal dynamics To increase scene access frequency Data volume and transmission constraints

8 Opportunity to Fly HICO on the ISS The ISS Japanese Experiment Module Exposed Facility (JEM-EF) provides a platform to fly experimental sensors HICO is an experiment to fly low cost technologies and space qualify them by demonstration in space. Airborne camera ruggedized and operated in 90% nitrogen atmosphere in aluminium box. Computer is ruggedized and operated in 90% nitrogen atmosphere in aluminium box. Pointing system is made from Aerotech Vacuum rated rotating stage HICO is the first spaceborne imaging spectrometer for coastal oceans use data to demonstrate algorithms and products. HICO image of Christchurch, New Zealand, August 7, 2011

9 Integrating HICO into HREP HICO flight imager in the Laboratory HICO with thermal blankets in the HICO/RAIDS Experiment Payload Both pictures NRL

10 HICO Launched to the ISS September 10, 2009 Launched from Tanegashima Island Space Center, Japan

11 HICO Installed on the ISS on September 24, 2009 HICO Japanese Module Exposed Facility HTV

12 HICO docked at ISS Now What? HICO Viewing Slit

13 HICO on the ISS Challenges Locations chosen based on: 1. Location within +/-52 o latitude limits of ISS orbit 2. Type ocean, coast, land (over 500 targets) 3. Uses CalVal, Science, Navy, EPA, NASA etc. Limitations: Orbit Operations One scene per orbit Clouds Example subset of over 500 targets

14 HICO Image of Chesapeake Bay: 10/09/09 Google Earth

15 Andros Island, Bahamas, Oct 22, 2009 RGB image Bathymetry Absorption

16 Microcystis bloom in Lake Erie HICO image of a massive Microcystis bloom in western Lake Erie, September 3, 2011 as confirmed by spectral analysis.

17 Derivative Spectroscopy with HICO Derivative spectrum after processing Comparing RISE Synthesis view of the plume (Hickey, et al, 2010, JGR 115: C00B17) and Columbia River 13 July 2010 HICO sediment product using Derivative Analysis (N. B. Tufillaro, preliminary results)

18 Western Australia Bathymetry and Classification HICO-derived bathymetry(left) and benthic classification product (right) for Eastern Shark Bay in Australia. (Peter Fearns and Lachlan McKenna, Curtin University, Perth, Australia, HICO Annual Report)

19 NASA Increases HICO data distribution Map of HICO images available from the NASA GSFC Ocean Color Website In 2013 NASA has taken over the operation of HICO and they are now making all HICO data widely available through the NASA Ocean Color Website at Goddard Space Flight Center. For more detailed information about HICO and HICO data and to request collection of new data researchers should continue to use the University HICO website. Ten new users have requested HICO data for their study sites in

20 The HICO Team NRL DC Mary Kappus Jeff Bowles Michael Corson Robert Lucke Bo-Cai Gao Charles Bachmann Ellen Wagner Karen Patterson Dan Korwan Marcos Montes Rong-Rong Li William Snyder NASA Cindy Evans William Stefanov Lisa Vanderbloemen Melissa Dawson Gene Feldman NRL SSC Rick Gould Paul Martinolich Will Hou David Lewis Adam Lawson Alan Weidemann Ruhul Amin Academic Curt Davis, OSU (Project Scientist) Jasmine Nahorniak, OSU Nick Tufillaro, OSU Zhongping Lee, U. Mass Boston Bob Arnone, USM Industry John Fisher, Brandywine Photonics Special thanks to our sponsors the Office of Naval Research, the DoD Space Test Program, NASA and JAXA who made this program possible.

21 HICO Summary: 4 Years and Counting Japanese Exposed Facility HICO Built and launched in 28 months Over 9000 scenes collected Data from NASA: Order new collections at:

22 Continuing Remote Sensing on the ISS Today HICO and RAIDS Demonstration instruments made on a very quick schedule and minimal budget ISS orbit limiting for HICO but good for RAIDS limb sounding Many new sensors being developed: ISS orbit very good for many atmospheric sensors ISS can handle large payloads and provide abundant power and cooling Launched on spacecraft already heading to the ISS Avoids cost of spacecraft Two Examples: CATS Lidar cloud and aerosol sensor SAGE III on ISS limb sounder Earth remote sensing on the ISS has a very promising future

23 Cloud-Aerosol Transport System (CATS) CATS is a laser-based (lidar) remote sensing payload for studies of atmospheric cloud and aerosol layers. Primary science goals include: Enable aerosol transport models by using near real-time data from ISS Improve understanding of aerosol and cloud properties and interactions Continue spacebased record of vertical profiles of cloud/aerosol properties Deploys to the ISS (JEM-EF) in Sept 2014 PI: Dr. Matthew McGill, NASA/GSFC Example (from airborne instrument) of lidar profiling, showing time-height cross-section of the atmosphere, revealing cirrus clouds, aerosol, and other atmospheric features.

24 SAGE III on ISS SAGE III on ISS will extend the long-term SAGE data record by making climate-quality ozone, aerosol, and other trace gas measurements Launch: mid-2015 Project Scientist: Joseph Zawodny, NASA Langley Program Scientist: Richard Eckman, NASA HQ