# Presentation: 177791

## Examples of Atmospheric Applications of Terra MODIS at the University of Wisconsin-Madison

- Cooperative Institute for Meteorological Satellite Studies
*http://cimss.ssec.wisc.edu*

** ****Cooperative Institute for ****Meteorological Satellite Studies**

## MODIS atmospheric investigations at UW

**	**(global products generated on the UW SCF)
- 	1 km water vapor
- 	multi-spectral cloud mask
- 	cloud heights with CO2 slicing
- 	cloud phase with tri-spectral window
- 	atmospheric temperatures
- 	Total Column Water Vapor
- 	Total column Ozone
- 	comparisons are made with GOES and AMSU/HIRS
**UW MODIS QA web site**
**	**http://cimss.ssec.wisc.edu/modis1/modis1.html
**Progress on Direct Broadcast**
- 	International MODIS/AIRS Processing Package

## MODIS 1 km resolution reveals fine-scale structure

**MODIS 1 km resolution reveals fine-scale structure**

## Cloud Mask

*Objective*: For every 1000 m pixel, determine whether the field of view is obstructed (usually by cloud). Operate day and night globally.
*Method*: Combination of spectral tests using visible, near-infrared, and infrared bands. Fuzzy thresholds are used.
*Result Categories*: Confident Clear, Probably Clear, Uncertain, Cloudy.
- Ackerman, S. A. et al. 1998: Discriminating clear sky from clouds with MODIS. *J. Geophys. Res.*, 103, 32141-32157.

## MODIS 2000/09/05-08

- Band 1 (0.66 μm) Daytime Clear sky Reflectance

## MODIS 2000/09/05-08

- Band 31 (11.0 μm) Daytime Clear sky Brightness Temperature

## MODIS 2000/09/05-08

- Band 1, 4, 3 (R/G/B) Daytime Clear sky Reflectance Composite

## Atmospheric Profiles

*Objective*: Retrieve profiles of atmospheric temperature and water vapor for every 5 x 5 box of 1000 m FOVs where at least 5 FOVs are clear. Also retrieve total column ozone.
*Method*: Statistical regression retrieval (for efficiency at launch). Physical simultaneous retrieval (post launch).
*Products*: Temperature and water vapor at 20 atmospheric levels (sampled from 101). Total column ozone and precipitable water.
- Li, J. and H. L. Huang, 1999: Retrieval of atmospheric profiles from satellite sounder measurements using discrepancy principle. *Appl. Opt.*, 38, 916-923.

## GOES vs. MODIS 2000/06/30 1600 UTC

- Total Ozone (Dobsons)

## MODIS 2000/09/05-08

- Daytime Total Ozone (Dobson Units)

## Earth Probe TOMS 2000/09/05

- Total Ozone (Dobson Units)

## GOES vs. MODIS 2000/06/30 1600 UTC

- Total Precipitable Water (mm)

## MODIS 2000/09/05-08

- Daytime Total Precipitable Water (cm)
- values over land not shown to facilitate comparison with AMSU

## NOAA-15 AMSU-A 2000/09/05

- Daytime Total Precipitable Water (mm)

## MODIS 2000/09/05-08

- Daytime 850 hPa Temperature (K)

## NOAA-15 AMSU-A 2000/09/05

- Daytime 850 hPa Temperature (K)

## MODIS 2000/08/23

- 500 hPa Temperature (K)

## NOAA-15 AMSU-A 2000/08/23 500 hPa Temperature (K)

## Cloud Top Properties

*Objective*: Retrieve cloud top properties for every 5 x 5 box of 1000 m FOVs where at least 5 FOVs are cloudy.
*Method*: Longwave infrared CO2 slicing; tri-spectral for cloud phase.
*Products*: Cloud top pressure and temperature; Cloud fraction and effective emissivity; Cloud phase (water, ice, mixed).
- Frey, R. A. et al, 1999: A comparison of cloud top heights computed from airborne lidar and MAS radiance data. *J. Geophys. Res.*, 104, 24547-24555.

## MODIS 2000/03/12 1730 UTC Cloud Mask

- snow

- Clear=green, cloud=white, uncertain=red

## MODIS 2000/03/12 1730 UTC Cloud Top Pressure

## Cloud top Pressure

- Cloud top Temperature

- Cloud Fraction

- Cloud Effective Emissivity

- MODIS 2000/09/05-08

## MODIS 2000/09/05-08  Percentage Water Cloud

## MODIS 2000/09/05-08  Percentage Ice Cloud

## International MODIS/AIRS Processing Package

*Goal:*
- Transform direct broadcast Level-0 data (initially from MODIS) to calibrated & geolocated radiances (Level-1B).
*IMAPP Features:*
-  Ported to a range of platforms (IRIX, SunOS, AIX, HPUX, Linux),
-  Only tool kit required is NCSA HDF 4.1r3,
-  Processing environment is greatly simplified,
-  Downlinked or definitive ephemeris/attitude data may be used,
-  Passes of arbitrary size may be processed,
-  Available at no cost; licensed under GNU GPL.
*Available from:*
*http://cimss.ssec.wisc.edu/~gumley/IMAPP/IMAPP.html*

## EOS Direct Broadcast Groundstation

**EOS Direct Broadcast Groundstation**

- TeraScan SX-EOS 4.4 m antenna: First data acquired 2000/08/18

- Overpass prediction 2000/10/13

## MODIS Band 2: 250 meter resolution

*MODIS Band 2: 250 meter resolution*
*UW-Madison Direct Broadcast 2000/10/13 1559 UTC*