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 vapormulti-spectral cloud maskcloud heights with CO2 slicingcloud phase with tri-spectral windowatmospheric temperaturesTotal Column Water VaporTotal column Ozone

comparisons are made with GOES and AMSU/HIRS

UW MODIS QA web sitehttp://cimss.ssec.wisc.edu/modis1/modis1.html

Progress on Direct BroadcastInternational MODIS/AIRS Processing Package

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 2000/09/05-08Band 1 (0.66 µm) Daytime Clear sky Reflectance

MODIS 2000/09/05-08Band 31 (11.0 µm) Daytime Clear sky Brightness Temperature

MODIS 2000/09/05-08Band 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 UTCTotal Ozone (Dobsons)

MODIS 2000/09/05-08Daytime Total Ozone (Dobson Units)

Earth Probe TOMS 2000/09/05Total Ozone (Dobson Units)

GOES vs. MODIS 2000/06/30 1600 UTCTotal Precipitable Water (mm)

MODIS 2000/09/05-08Daytime Total Precipitable Water (cm)

values over land not shown to facilitate comparison with AMSU

NOAA-15 AMSU-A 2000/09/05Daytime Total Precipitable Water (mm)

MODIS 2000/09/05-08Daytime 850 hPa Temperature (K)

NOAA-15 AMSU-A 2000/09/05Daytime 850 hPa Temperature (K)

MODIS 2000/08/23500 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

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

Overpass prediction 2000/10/13

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