# Presentation: 516815

## High Resolution MODISOcean Color

**Bryan Franz**
- NASA Ocean Biology Processing Group

- MODIS Science Team Meeting, 4-6 January 2006, Baltimore, MD

## Concept

- The goal is to investigate the utility of  the 250 and 500-meter land bands for ocean color applications. (*talk by Arnone, posters by Gould, Gao*)

## MODIS Land Bands

- Band	Wavelength	Resolution
- 1		645			250
- 2		859			250
- 3		469			500
- 4		555			500

## MODIS Land Bands

- Band	Wavelength	Resolution
- 1		645			250
- 2		859			250
- 3		469			500
- 4		555			500
- 5		1240 * 		500
- 6		1640			500
- 7		2130			500

** band 5 failing on MODIS/Aqua*

## Concept

- The goal is to investigate the utility of  the 250 and 500-meter land bands for ocean color applications.
- A second goal is to investigate the use of the short-wave IR bands for use in atmospheric correction, especially for coastal applications. (*paper by Wang & Shi*)

## Concept

- The goal is to investigate the utility of  the 250 and 500-meter land bands for ocean color applications.
- A second goal is to investigate the use of the short-wave IR bands for use in atmospheric correction, especially for coastal applications.
- Develop these capabilities for regional analyses by SeaDAS users, not for global production.

## Concept

- The goal is to investigate the utility of  the 250 and 500-meter land bands for ocean color applications.
- A second goal is to investigate the use of the short-wave IR bands for use in atmospheric correction, especially for coastal applications.
- Develop these capabilities for regional analyses by SeaDAS users, not for global production.
- The approach is to define a virtual sensor (HIRES MODIS) which includes all the 250 and 500-meter channels, as well as a sufficient set of 1km ocean channels to enable the operation of most standard ocean product algorithms.

## HIRES MODIS

- Band	Wavelength	Resolution	SNR	(1km SNR)
- 8	412		1000		880
- 9	443		1000		838
- 3	469		500		243	(802)
- 4	555		500		228	(750)
- 1	645		250		128 	(910)
- 15	748		1000		586
- 2	859		250		201	(516)
- 5	1240 * 	500		74
- 6	1640		500		275
- 7	2130		500		110

** band 5 failing on MODIS/Aqua*

## RGB ImageStandard MODISvsHIRES MODIS

- 1-km

- 250-meter

- 75%

## Progress to Date

- Initial implementation of HIRES MODIS processing into MSL12
- replicating radiances and path geometries to 250-meter pixels
- interpolating geolocation to 250-meter resolution
- developed polarization LUTs for the land bands
- obtained Rayleigh tables from M. Wang
- interpolating aerosol tables
- Initial vicarious calibration to MOBY
- obtained MOBY radiances for the land band spectral response functions from D. Clark.
- Testing and refinement of software and approach underway
- coordination with NRL/Stennis

## Ocean Color Processing Test

- Using fixed aerosol type, with aerosol concentration from 859-nm band at 250-meter resolution
- OC2 chlorophyll algorithm using 469 and 555-nm bands at 500-meter resolution (*P. J. Werdell*).

## Chlorophyll Standard MODISvsHIRES MODIS

- 1-km

- 250-meter

- Chlorophyll Standard MODISvsHIRES MODIS

- 75%

## 1-km

- 250-meter

- 70%

- 280%

## Full 5-minute Granule

- 250m nLw(555)

## Practical Considerations

- The OBPG does not retain the land-band data within the ocean data processing and distribution system. The 250 and 500-meter data are removed from the Level-1A file during ingest.
- Full Level-1A or Level-1B files must be obtained from the GES DAAC or via Direct Broadcast. DAAC L1A holdings are limited.
- Each resolution is stored in a separate Level-1B file (1KM, HKM, QKM) .  All three are required to run 250-meter processing.
- Given Level-0 (Direct Broadcast) or Level-1A, the SeaDAS software can produce the three L1B files using the latest LUT.
- The files are big. Memory requirements are high.
- Level-1B 1KM+HKM+QKM = 900MB (5 minute granule)

## Future Plans

- Improved implementation into MSL12
- interpolate all radiances and path geometry to 250-meter
- maybe include other 1km bands (488, 869) ?
- flexibility to switch resolution (1000m, 500m, 250m), utilizing aggregated radiance fields from Level-1B
- Investigate use of SWIR bands for atmospheric correction
- 1240 & 1640 (Terra)
- 1640 & 2130 (Terra & Aqua)
- Develop capabilities for subscene extraction at Level-1A
- Enhance SeaDAS to support HIRES MODIS
- processing and display

## End