Environmental Science from Satellites

1. Environmental Sciencefrom Satellites Jeff Dozier, UCSB

2. Radiation principles

3. Atmospheric absorption of solar and infrared radiation NASA Goddard Institute for Space Studies http://www.giss.nasa.gov

4. Measurement scale constrained by physics and technology (and money) • Spatial resolution (IFOV/GSD) and coverage (field-of-view/regard) • Optical diffraction sets minimum aperture size • Spectral resolution (Dl) and coverage (lmin to lmax) • Narrow bands need bigger aperture, more detectors, longer integration time • Radiometric resolution (S/N, NEDr, NEDT) and coverage (dynamic range) • Aperture size, detector size, number of detectors, integration time • Temporal resolution (revisit) and coverage (repeat) • Pointing agility, period for full coverage

5. Spatial, spectral characteristics of some multispectral sensors

6. Aircraft hyperspectral data (AVIRIS) 0.4 m  2.5 m

7. Data rate

8. Gulf Stream temperatures from MODIS, May 2, 2001

9. SeaWiFS image—global chlorophyll July 1997 - Sept 1998 Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center and ORBIMAGE

10. Fractional snow cover, Sierra Nevada, March 7 2004

11. Surface elevation from interferometric radar (full resolution image is available from the JPL SRTM image website)

12. Applications: snowmelt modeling(Molotch et al., GRL, 2004) Snow Covered Area net radiation> 0 degree days > 0 Where: mq= Energy to water depth conversion, 0.026 cm W-1 m2 day-1

13. Surface wetness with AVIRIS, Mt. Rainier, 6/14/96 AVIRIS image, 409, 1324, 2269 nm precipitable water, 1-8 mm liquid water, 0-5 mm path absorption vapor, liquid, ice (BGR)

14. A Use Present B Collect Retrieve C Store Search Information Lifecycle Collect Store Present Use Search Retrieve

15. 2005 status • Universal connectivity (except Africa, South America) • Internet • Web • Comprehensive analysis environments • GIS, image analysis (ArcGIS, ENVI) • Matrix manipulation (IDL, MATLAB, …) • Standard formats • Metadata (FGDC, …) • Data (XML, GeoTIFF, …)

16. A Do complex analyses, many with off-the-shelf tools B Retrieve/publish data from/to the Web C Can’t find somebody else’s data / they can’t find yours How good is your web site? Can’t remember what you did / how you did it How good are your notes? Your conclusions are in the archival literature;where are your data? How good are your backups? 2005 report card

17. Local Storage management Everything onlineand accessible Metadata management Everything documented and findable Everything connected to where it came from Global Federation Distributed data centers look like a single system Service management Discover, query, describe, and retrieve information Namespace management Same names for same things Major Missing Pieces  Personal data centers  Digital libraries

18. Earth System Science Workbench: conceptual model (ESIP—Earth Science Information Partners) • Experiment • Network of models • … ingesting / synthesizing data • … generating products • Notebook • Persistent storage that can be queried • Keeps track of all experiments • Laboratory • Experiment execution environment

19. CD-ROM Combining sensors: sea-surface temperature and height HRPT Data Handling HRPT Gridding calibrate, de-cloud, aggregate TeraScan extrapolate HRPT downlink AVHRR image SST “super data” SST grid GOAL: Local and advective components of upper ocean heat balance: TOPEX Data Handling TOPEX Gridding ocean height grid ocean height “super data” TOPEX points MGDR cracker calibrate, aggregate extrapolate

20. avhrr_L0 AVHRR Level 0 product AVHRR telemetry ingest avhrr_ingest Hand navigation details avhrr_l1b AHVRR Level 1B product Hand navigation avhrr_ procedure handNav avhrr_ AVHRR Level 1B: navd_l1b Multi-channel navigated sea surface avhrr_ temperature sstModel algorithm avhrr_sst Sea surface temperature (SST) Copy avhrr_ navigated copyNav image avhrr_ navd_sst SST: navigated

21. AHVRR Level 1B product avhrr_l1b Multi-channel sea surface temperature algorithm avhrr_ sstModel Sea surface temperature avhrr_sst (SST) # SST experiment wrapper # $L1B is the input Level 1B AVHRR image file # $SST is the output SST image file # run legacy command "nitpix": creates SST image from L1B image $base_temp = 5.0; $temp_step = 0.1; ... system("nitpix base_temp=$base_temp temp_step=$temp_step ... $L1B $SST"); # start recording ESSW metadata beginXMLBld($ENV{USER}, "PRODUCTION"); # get metadata for input file $L1B_ID = findSciObjFromFile($L1B);

22. AHVRR Level 1B product avhrr_l1b Multi-channel sea surface temperature algorithm avhrr_ sstModel Sea surface temperature avhrr_sst (SST) # create metadata for SST experiment $exp = createExperimentMetadata("avhrr_sstModel"); $exp_step = createExpStepMetadata($exp, "avhrr_sstExpStp"); addValue($exp_step, "avhrr_sstExpStp.base_temp", $base_temp); addValue($exp_step, "avhrr_sstExpStp.temp_step", $temp_step); ... saveToDB($exp_step, "avhrr_sstExpStp"); closeMetadata($exp_step); # connect input and output images to experiment registerExperimentInputs($exp, $L1B_ID); registerExperimentOutputs($exp, $SST_ID); # finish recording ESSW metadata endXMLBld();