spacer
spacer
spacer
spacer

NASA Link SEE Link nasa see logo

Go
spacer
SEERS       
spacer
spacer

SEE Home
SEE Program
 
whats new
introduction
organization
twg
model and database
flight experiments
publications
links nav button
spacer
Tech Development Activity - present and past...
learn more>>

High School Lesson Plan,
toolkit... 
learn more>>

Image Gallery -
SEE, SEERS images>>

 
Go
spacer
  SEE PRODUCTS / SEE Related Model & DB -
Ionosphere and Thermosphere (Solar and Thermal Environment)

EARTH GLOBAL REFERENCE ATMOSPHERIC MODEL (Earth-GRAM 2007)

What's New:

Earth-GRAM 2007 Version 1.1 Upgrade

Some minor changes to the original Earth-GRAM2007 have been made that may affect particular applications.  They include:
 
*  Changes to the initial radll subroutine to calculate great-circle lat-lon distance with a more precise routine (based on cross product and sine of angle,
rather than dot product and cosine of angle). 
 
*  Adjustments of the temperature perturbation magnitude at high altitudes (> 90 km).
 
*  Corrects the name of subroutine GeodettoGeocent_E07.
 
*  A code patch to prevent standard deviations from updating if iupdate is off (<0).  This has no effect on stand-alone Earth_GRAM, and applies only for gramtraj implementations in trajectory codes that use the iupdate feature to update mean values, without updating perturbations.
 
*  Adds a test in the radll function to make it more robust.
 
*  Prevents a terminal error condition from occurring if points below sea level are reached and the max number of points has not been reached.

 


Description:

Global model, using empirical database, giving density, temperature, pressure, winds, and selected atmospheric constituent concentrations, from the surface of the Earth to orbital altitudes, as a function of geographic position and time of year. Local perturbations about mean conditions are also included. Model is also suitable for use as a subroutine in a trajectory code or orbit propagator program or other programs used for simulations of in-flight or on-orbit atmospheric variability in density, temperature, or winds.

New Features of GRAM 2007 -

Revised Range Reference Atmosphere (RRA) data - In 2006, the Air Force Combat Climatology Center (AFCCC) developed a set of revised Range Reference Atmosphere (RRA) data including several new sites.  Earth GRAM-07 has the option of using either the 2006 revised RRA data, or the earlier (1983) RRA data, as a replacement for conventional Earth GRAM climatology.      + Read More Features

Additional Information:

Language: FORTRAN 77

Operating System: PC/DOS, Unix

Hardware Requirements: Runs on PC (or compatible) and on most Unix hardware, must have CD- ROM for Global Upper Air Climatic Atlas (GUACA) data set. Need at least 20 MEG of storage space.

Availability:

  • Maintenance/ Upgrades: On an as needed basis
  • Source Code: Source code is available
  • Cost: Program: No cost to qualified, NASA approved users
  • Distribution: Available upon request at
    http://see.msfc.nasa.gov/ModelDB/ModelDB.htm
  • Manuals: Yes
  • Training: No

Input Description: Geographic position, time, GUACA data (for heights below 27 km),  solar and geo-magnetic data (for heights above 90 km)

Output Format: Density, temperature, pressure, winds, and selected atmospheric constituent concentrations, from the surface of the Earth to orbital altitudes.

Verification/ Validation: Model is based on empirical data and validated against other empirical data and previous models.

NOTE:  GRAM 2007 includes the option to use Global Upper Air Climatic Atlas (GUACA) or Global Gridded Upper Air Statistics (GGUAS) CD-ROM data sets for 0-27 km altitudes.  Please click here to obtain ordering information for the GUACA and GGUAS data sets.  If you have any additional questions, please don't hesitate to contact us.

Point of Contact:

C. G. (Jere) Justus
EV13/UNITeS
NASA Marshall Space Flight Center
MSFC, AL 35812
Phone: (256)-544-3260
E-mail: Carl.G.Justus@nasa.gov

Fred Leslie
EV13/NASA
NASA Marshall Space Flight Center
MSFC, AL  35812
Phone: (256) 544-1633
E-mail: Fred.W.Leslie@nasa.gov


back to SEE Products - Ionosphere and Thermosphere

   


  FirstGov - Your First Click to the US Government
+ Inspector General Hotline
+ Equal Employment Opportunity Data Posted Pursuant to the No Fear Act
+ Budgets, Strategic Plans and Accountability Reports
+ Freedom of Information Act
+ The President's Management Agenda
+ Privacy Policy and Important Notices


NASA
Curator: Sopo Yung
NASA Official: Dr. David Edwards

+ Contact SEE
spacer
spacer