8th ioccg meeting in florence, italy (24-26 feb 03) current status of modis (terra and aqua) by...

8th IOCCG Meeting in Florence, Italy

(24-26 Feb 03)

Current Status of MODIS (Terra and Aqua)

byChuck Trees for the

MODIS Team Members

Brief MODIS History

• Definition Panel 1984• Selection of Instrument, Instrument Team - 1989• Restructuring - 1992

– MODIS-T out, PM MODIS-N in (6 MODIS-N’s)• Major budget reduction - 1997

– Addition of team member investigations– DIS rescope– 6 platforms reduced to 1st 2 - AM-1, PM-1

• Launch Terra 12/1999• Launch Aqua 5/2002

• Re-compete team in mid 2003

TERRA MODIS NIGHTTIME 4m SST

MODIS/OCEAN GROUPGSFC, RSMAS

-2 5 10 15 20 25 30 35Co

MAY 2001 V 3.3.1

MODIS SST Buoy and M-AERI retrieval StatisticsVersion 4.5 (new delivery)

median = satellite - reference [MAERI or BUOY]

BUOY M-AERI• SST - new coefficients

Median StdDevNumber

of Points

– Terra all -0.07 0.48 11027– Terra night 0.01 0.42 4387– Terra day -0.14 0.51 6643– Aqua all -0.05 0.48 3821– Aqua night -0.10 0.43 1628– Aqua day -0.01 0.51

2203

• SST4 new coeffs, new formulation– Terra night -0.05 0.41 4096– Aqua night -0.10 0.39 1319

• SST - new coefficients Median StdDev Number

of Points

–Terra all 0.10 0.40 439

–Terra night 0.04 0.35 235

–Terra day 0.16 0.42 204

–Aqua all 0.06 0.40 105

–Aqua night 0.02 0.37 59

–Aqua day 0.11 0.45 46

• SST4 new coeffs, new formulation–Terra night 0.02 0.34 278

–Aqua night -0.01 0.31 52

AQUA, TERRA combined orbits nearly eliminate swath gaps

Composite AQUA, TERRA SST Night Sept 29, 2002

Nearly Complete Single Day Global CoverageComposite Night (MODIS-T, MODIS-A)

Day, Night - (AMSR, TMI) Prototype Sept 29, 2002, 0.25O spatial resolution

Kyle

MODIS Ocean Products• MODIS Instruments:

– Terra (1030 morning),

– Aqua (1330 afternoon)

• 40 products: – 4 SST,

– 36 Ocean Color

• Resolution:– Spatial:

• Level 2 - 1km, ~2000km x 2000km;

• Level 3 - 4km, 36km, 1 deg [all products are global]

– Temporal Resolution:• Level 2 - 5 minute granule;

• Level 3 - daily, 8 day week, monthly, yearly

MODIS Ocean data products• There are 86 ocean parameters available in over 100 categories of

MODIS Ocean data types archived by (and may be obtained from) the NASA Goddard Distributed Active Archive Center.

• The three basic groupings of MODIS ocean data parameters are:– ocean color– sea surface temperature– ocean primary production

• Ocean Parameter categories:• 36 Ocean Color parameters• 4 Sea Surface Temperature parameters• 8 Primary Productivity parameters

– (including 2 Primary Production indices)• 38 Quality Control parameters.

•Next reprocessing (TERRA Collection 5)

•Combined Terra and Aqua products

1. New cross-scan normalization based on individual detectors. This improves detector gain stability across the scan, thereby improving stripe removal.

2. Sun glint correction using vector winds to improve the east-west adjacent swath edge consistency.

3. Ocean BRDF correction

•Next reprocessing Terra Collection 4 in May 2003 1. Calibration issues and discontinuities will be corrected

for time period of Sept. 2001 - Dec 2002

Future Data Releases

TERRA Collection 4

AQUA Collection 3

Merged Terra, Aqua, SeaWiFS Chlor_a_2January 19, 2003full time series available in SeaWiFS 9km formathttp://jeager.gsfc.nasa.gov/browsetool/

2000 2001 2002

Valid period 305-800

Comparison of MODIS Chlorophyll Products

June 2001 Chlor_a_2 Chlor_a_3

(empirical) (semi-analytical)

Note that Chlor_a_3 results are similar for northern subtropics, but higher north of 40o N and for upwelling areas, where it has adjusted to higher-

nutrient effects.

Comparison between Chlor_a_3 SemiAnalytic and OC4v4 algorithms for Chlorophyll a for the Antarctic and

Southern California Bight upwelling zone

Note the large negative bias for the SeaWiFS algorithm and the improved performance for the semi-analytic Chlor_a_3 algorithm compared to in situobservations

Southern CaliforniaBight

AntarcticSemi-analytic

AntarcticSeaWiFS

Independent Validation StudyGregg and Casey, in progress

NODC + SeaBASS, L-3 4.6kmQuality Level 0, 1

Chlor_a_2 virtually identical performance as for SeaWiFSr2 = 0.757 n=1.6K vs 0.759 n>4.5K

Semi-analytic Chlor_a_3 shows improvement r2 = 0.784

Regional analysis is underway.

Chlor-MODIS

Chlor_a_3

Chlor_a_2

Watson Gregg & Nancy McCabe

OCEAN PRODUCTIVITY from MODIS : A New Baseline

Validated data period

Esaias et al. Poster:Compares Ocean Production using MODIS, SeaWiFS, different chlorophyll algorithms two production modelsMODIS Semi-analytic chlorophyll results in 2 x greater production in the key Southern Ocean regions, and phase differences, global total between 57 and 59 GT C. SeaWiFS/MODIS differences are relatively small.

Above: Mixed layer Ocean Production Index P2Standard MODIS Product Collection 4

Terra ONPP time series using chlorophyll from SeaWiFS (green), MODIS Chlor_a_2(SeaWiFS analog) (black), Chlor_MODIS(red), MODIS Chlor_a_3 Semi-analytic chlorophyll(blue) for global and 2 SO regions.

Global average

South Atlantic 10S° to 50°S

Antarctic, S of 50°S

Weekly FLH

Weekly Productivity (P1)

(From Frank Hoge and Paul Lyon)

FLH vs. chlorophyll

FLH vs. CDOM

Where to get data and more informationInformation locations:MODIS Oceans home page

– http://modis-ocean.gsfc.nasa.govMODIS Oceans QA Browse 36km Imagery (MQABI)

– http://jeager.gsfc.nasa.gov/browsetool/Select Terra collection 4

Useful links to documentation and related web pages– http://modis-ocean.gsfc.nasa.gov/doclinks.html

Data Ordering locations:NASA GES DAAC WHOM (NASA - Goddard DAAC)http://daac.gsfc.nasa.gov/

– Select Ocean color ->MODIS->oceanEOS DATA GATEWAY EDG

- http://modis.gsfc.nasa.gov/data/ordering.html