# Presentation: 119283

## Interrogating MODIS & AIRS data using HYDRA

- Paul Menzel
- NOAA Satellite and Information Services
- What is HYDRA?
- What can it do?
- Some examples
- How to get it?

## HYperspectral viewer for Development of Research Applications - HYDRA

**HYperspectral viewer for Development of Research Applications - HYDRA**

**http://www.ssec.wisc.edu/hydra/**

- MSG,
- GOES

- MODIS,
- AIRS, CALIPSO

- Developed at CIMSS by
- Tom Rink
- Tom Whittaker
- Kevin Baggett
- With guidance from
- Paolo Antonelli
- Liam Gumley
- Paul Menzel

- Freely available software
- For researchers and educators
- Computer platform independent
- Extendable to more sensors and applications
- Based in VisAD
-  (Visualization for Algorithm Development)
- Uses Jython (Java implementation of Python)
- runs on most machines
- 512MB main memory & 32MB graphics card suggested
- on-going development effort

**Notes:**
V1.7.4
Transect: Now supported in the psuedo-channel display. Fixed a bug when the user failed to 'drag out‘ a line.         Generally more robust, will update to change in projection, subset.  Works in instrument projection.          ** Note:  only one transect per session.  If you transect on the MCV, you should close          the transect window before you start one on the psuedo-channel window.  I'll add multiple          independent transects in v1.7.6. Planck function:  I've just really started this, but for MODIS and AIRS you can type 'radToBT(value)'     and 'BTtoRad(value)' at the >>>  in the run window.  It uses the channel currently selected in the MCV for     the wavelength, so only have one MCV up when you     do this.  I'll improve this for v1.7.6.  Things are a     little different on the ADDE side, so this won't work  for MSG or GOES - next rev. 

## Freely available software

**For researchers and educators**
**Computer platform independent**
**Extendable to more sensors and applications**
**Based in VisAD**
** ****(Visualization for Algorithm Development)**
**Uses Jython (Java implementation of Python)**
**runs on most machines**
**512MB main memory & 32MB graphics card suggested**
**on-going development effort**
**http://www.ssec.wisc.edu/hydra/**

## The HYDRA Window

## Loading a Granule

- HYDRA IR window with 29 May 2001 MODIS L1B 1KM granule

## Select region for full resolution display

## Select colorandZoom to see single pixel resolution

## Multichannel Viewer

***Under Tools***
***Linear Combinations*** opens *Channel Combination Tool*  display where you can specify linear combinations of spectral bands a,b,c and d
- (a   +-x /   b)   +-x /    (c   +-x /   d).
***RGB ***allows you to select a spectral channel for each color in the RGB display
***Transect ***allows you to create a line on the image and see the temperatures or radiances along the transect marked by shift plus right click and drag.
***Capture Display*** allows you to save the image as a jpeg*** ***
***Statistics ***displays the min and max values in the image
***Reference Spectrum*** allows you to compare spectral measurements from two selected pixels (controlled by the arrows in the bottom toolbar)

**r****ν**** (black)           BT****ν**** ****(purple)**

**BT6.7**

## Pseudo RGB Composite Image

**Red – ch 1**
**   ****0.65 ****μ****m**
**Green – ch 4**
**   ****0.55 ****μ****m**
**Blue – ch 3**
**   ****0.47 ****μ****m**

## Transect

## Linear Combination BT4 – BT11

## Linear Combination BT4 – BT11

**BT4 – BT11**

**Notes:**
Large positive values of BT4-BT11 occur where reflected solar contributions are increasing BT4 – clouds and low fog and sunglint on open water are obvious

## Transect

- BT4 > BT11 in low clouds along coastline

**BT4**

## Comparing IR to NIR Cloud Detection

**Thin cirrus show up in BT8.6-BT11 (left) as well as r1.38 (right)**

## Setting up for scatter plot of BT11 vs r0.66 

## Scatter Plot of rvis vs BT11with colors highlighting locations of pixels in plot on images

## Linear Combinations Pseudo Image of Normalized Vegetation Index [(r2 -r1 )/(r2 +r1)]

## MODIS level 2 cloud mask display

- clear =green
- probably clear (95%
-    certain) = turquoise uncertain = red
- cloudy = white

## Interrogating MODIS & AIRS data using HYDRA

- Paul Menzel
- NOAA Satellite and Information Services
- What is HYDRA?
- What can it do?
- Some examples with AIRS
- How to get it?

## AIRS data over Black & Caspian Seas 28 August 2005 

- AIRS data over Black & Caspian Seas 28 August 2005

## BT1384.5 minus BT1387.2

- BT differences of more than 40 K are seen in clear regions and less than 1 K in opaque high cloudy regions

## Investigating AIRS Retrievals

- On-line off-line BT difference is greater
- in western (blue x) than eastern (red dot) location of Black Sea;  x has more low level moisture than dot.
- This is confirmed by moisture profiles (upper left); 900 hPa retrieved moisture image (lower left)
- shows moisture gradients

## AIRS (right) and MODIS (left) co-located display of spectra 

## Interrogating MODIS & AIRS data using HYDRA

- Paul Menzel
- NOAA Satellite and Information Services
- What is HYDRA?
- What can it do?
- Some examples with CALIPSO
- How to get it?

- 15 Jun 06 225 UTC (day)

**Notes:**
Attenuated backscatter at .532 microns

## Interrogating MODIS & AIRS data using HYDRA

- Paul Menzel
- NOAA Satellite and Information Services
- What is HYDRA?
- What can it do?
- Some examples
- How to get it?

**Go to www.ssec.wisc.edu/hydra/**

**http://rapidfire.sci.gsfc.nasa/realtime**

**Access data at http://daac.gsfc.nasa.gov/**

## Access data at http://ladsweb.nascom.nasa.gov/data/

**Access data at http://ladsweb.nascom.nasa.gov/data/**

## For hydra

**http://www.ssec.wisc.edu/hydra/**

**For data and quick browse images**
**http://rapidfire.sci.gsfc.nasa/realtime**

**For MODIS and AIRS data orders **_[http://daac.gsfc.nasa.gov/](http://daac.gsfc.nasa.gov/)_
**After mid Aug 2006 go to **
- _[https://l](https://ladsweb.nascom.nasa.gov/)__[adsweb.nascom.nasa.gov](https://ladsweb.nascom.nasa.gov/)__/data_

## HYDRA has been part of an effort for 

**Environmental Literacy, Outreach, and Education**
**Schools on remote sensing**
**have been held in**
- Bologna, Italy (Sep 01),
- Rome, Italy (Jun 02),
- Maratea, Italy (May 03),
- Bertinoro, Italy (Jul 04),
- Cape Town, South Africa (Apr 06),
- Krakow, Poland (May 06),
- Ostuni, Italy (Jun 06)