GHRC/ITSC-Developed Tools

The following tools have been developed at the Global Hydrology Resource Center and the Information Technology and Systems Center at the University of Alabama.

• HyDRO
  You can search through the dataset holdings at the GHRC using HyDRO, the Hydrologic data Search, Retrieval, and Order system. HyDRO can provide you with a list of GHRC datasets specific to your requirements. You can then browse through the online information for each dataset, download the online datasets, or place an order for any offline datasets.

• Coarse-Grain Subsetter
  The Coarse-Grain SSM/I Subsetter is a specialized subsetter for Special Sensor Microwave/Imager (SSM/I) data, which is currently available at the Global Hydrology Resource Center (GHRC) Data Pool. Each SSM/I data file is composed of a set of geographically discrete "subgranules". This subsetter very quickly extracts the subgranules that cross the user's area of interest. "Coarse grain" subsetting greatly reduces the volume of data delivered, but requires minimal data center resources.The SSM/I Subsetter allows you to subset any of the online (most recent two years) SSM/I swath data by selecting a date range and geographic region. For subsetting requirments outside of this window, please contact GHRC User Services.
  
  
• Dataset-Independent Subsetter (HEW)
  The Dataset-Independent Subsetter (HEW) can subset properly-formatted HDF-EOS data files on latitude/longitude bounding boxes as well as on date/time spans. HEW can also select only the channel information you want from an HDF-EOS file. The TMI and AMSU-A datasets can be subsetted by HEW.
  
  
• SPOT: A "Subsettability Checker" for HDF-EOS Files
  A companion program to HEW, SPOT can be used to check HDF-EOS files for subsettability by HEW. In "verbose" mode, SPOT displays the HDF-EOS structures as it checks them. In "silent" mode, only error messages are output. In both cases, the exit status is set to reflect the "subsettability" of the file.
  
  
• Algorithm Development and Mining System (ADaM)
  The Algorithm Development and Mining System (AdaM) developed by the Information Technology and Systems Center at the University of Alabama in Huntsville is used to apply data mining technologies to remote sensed and other scientific data. ADaM provides a toolkit of pattern recognition, image processing, optimization, and association rule mining capabilities. Using common scripting languages, such as Python, Perl, and shell, ADaM components can be used to solve complex data analysis problems.
  

• Earth Science Markup Language (ESML)
  Handling the vast number of heterogeneous data formats found in scientific data sets results in a large data preprocessing effort for most researchers. The Earth Science Markup Language (ESML) has been researched and developed by ITSC to assist in easier data access and utilization. ESML is an interchange technology that enables data (both structural and semantic) interoperability with applications without enforcing a standard format within the Earth science community. Users can write external files using ESML schema to describe the structure of the data file. Applications can utilize the ESML Library to parse this description file and decode the data format. As a result, software developers can now build data format independent scientific applications utilizing the ESML technology.
  

• Web Map Services--Visualization and Data Access
  An OGC-compliant web map service is available for AMSU-A, TMI, and SSM/I data on the GHRC Data Pool . A web map service returns the image of one specific data layer that users/applications can then overlay or merge with other data layers to create composite maps. The Open Geospatial Consortium (OGC) is an international consortium of industry, government agencies and educational institutions striving to standardize interfaces and protocols for using geospatial data.
  

• NLDN Subsetter
  No longer does a researcher need to crawl through the entire NLDN dataset. The NLDN Subsetter, needs only the latitude and longitude of a geographic box along with the time period of interest to greatly reduce the volume of data. The subsetter will zip through the entire NLDN dataset for the time period designated, and repackage the data into daily files which contain only those lightning events which occur in the user defined box.
  NOTE: DISTRIBUTION OF NLDN DATA IS RESTRICTED TO EARTH OBSERVING SYSTEM (EOS) AND TRMM AFFILIATED INVESTIGATORS. WHEN CONTACTING THE GHRC FOR THE FIRST TIME WITH REQUEST FOR NLDN DATA, PLEASE PROVIDE YOUR NASA CONTRACT NUMBER.
  Request subsetted data from GHRC User Services.
  
  
• NLDN/BLDN Movie Maker
  Animated movies of lightning events for a user-specifed area from the NLDN and BLDN datasets can be custom generated for you. The user must specify latitude, longitude, and a center point location in the United States or Brazil for the animation. Users must also tell the GHRC User Services the start time, and duration and interval between the frames for the movie making.
  NOTE: DISTRIBUTION OF NLDN DATA IS RESTRICTED TO EARTH OBSERVING SYSTEM (EOS) AND TRMM AFFILIATED INVESTIGATORS. WHEN CONTACTING THE GHRC FOR THE FIRST TIME WITH REQUEST FOR NLDN DATA, PLEASE PROVIDE YOUR NASA CONTRACT NUMBER.
  Request movies from GHRC User Services.
  
  
• Coincidence Search Engine
  The Coincidence Search Engine allows you to determine when up to four satellites were within a geographic area or within a specified distance of each other simultaneously.

Third-Party Tools

The following tools have been developed by third parties. NASA, UAH, and the GHRC make no endorsement of these software tools. The tools have been designed to work with the data formats and may be useful to you in your research.

• Hierarchical Data Format
  The Hierarchical Data Format (HDF) is a popular data format that can be used to store a variety of data "objects", such as arrays, annotations, and images. The HDF libraries, available for FORTRAN and C programmers, have been ported to a variety of platforms.

• netCDF
  NetCDF (network Common Data Form) is an interface for array-oriented data access and a library that provides an implementation of the interface.

• FERRET
  A data visualization package.

• Noesys
  Noesys is a unique environment for desktop science data mining.

• IDL
  IDL (Interactive data Language) is a analysis and visualization tool.

• LinkWinds
  LinkWinds is a visual data exploration system resulting from a program of research into the application of computer graphics to rapidly and interactively accessing, displaying, exploring and analyzing large multivariate multidisciplinary data sets.

• GNU ZIP
  To save transmission time, files are often compressed using GZIP, available from www.gnu.org.

• HDFLook
  HDFLook is a comprehensive application for viewing NCSA HDF v.4.x and HDFEOS 2.x science datasets.

NASA Information Contact: Michael Goodman, Global Hydrology and Climate Center GHRC Web Curator: GHRC Web Team Last update: Friday, 13-May-2005 00:07:05 CDT If you have trouble viewing or navigating this page, please contact GHRC User Services. U.S. Government Compliance report.