Frequently Asked Questions
Who are the curstomers of the Goddard DAAC ?
The Goddard supports research and interdisciplinary scientists as well as
Earth science educators and university students. Many of our data products
are derived from full resolution research data products. For example, we
are currently producing a CD-ROM set based on the Nimbus-7 TOMS ozone dataset
which includes a variety of information and analysis tools to support use by
the education community.
What types of data does the Goddard DAAC distribute ?
The Goddard DAAC archives and distributes data gathered in atmospheric
dynamics, upper atmosphere, and global biosphere experiments. These
digital computer data are either in gridded (tabular) or image format,
depending of the dataset. The data are not photographs or video animations.
The specific datasets supported are :
- Upper Atmosphere Research Satellite (UARS)
- Total Ozone Mapping Satellites (TOMS)
- Coastal Zone Color Scanner (CZCS)
- Sea-viewing Wide Field of View Sensor (SeaWiFS)
- Pathfinder Advanced Very High Resolution (AVHRR) land sensor
- 4-Dimensional Assimilation dataset
- Total Ozone Vertical Sounder (TOVS) Pathfinder data
- Tropical Ocean Global Atmosphere (TOGA) Coupled
Ocean-Atmosphere Response
- Experiment (COARE) Field Observation experiment data
How can I find out if the Goddard has the data I need ?
The Goddard DAAC provides access to our data products through a menu-driven,
on-line search and order service called the Information Management System
(IMS). This service allows you to construct a query based on spatial or
temporal criteria, geophysical parameters and data processing level for the
type of data you are interested in. Both summary and detailed information
is displayed describing datasets fitting your criteria. Once you decide on
a dataset suiting your interest, you can select a range of individual data
files to order.
What do I need to access the Goddard DAAC on-line system ?
The Goddard DAAC on-line system is a character-based menu system. All you
need is a basic alpha-numeric terminal that can emulate a VT100, and either
a modem or internet connectivity.
You may also use a graphical or X-based terminal, but the graphics
capabilities will not be used.
What if I I'm using a PC ?
IBM PCs and clones have an 8 character filename limit. Currently the
Goddard DAAC uses more than 8 characters for some of its file names,
resulting in a truncated file name when transferred to a PC.
Is there a technical support staff who can answer any questions I might have using the system ?
The Goddard DAAC User Services Office is staffed by knowledgeable staff to
help you with the on-line ordering service, as well as any questions you
have concerning data and services available from other archive centers.
Our User Services staff also trains educators and students in finding and
using data, provides demonstrations at science conferences, and offers
expert advice on the uses and limitations associated with specific data
sets. Contact our User Services office at:
Phone: (301) 286-3209
Fax: (301) 286-1775
e-mail: daacuso@daac.gsfc.nasa.gov
Goddard Distributed Active Archive Center
Global Change Data Center, Code 902.2
NASA Goddard Space Flight Center
Greenbelt, MD 20771
What media and formats are offered for data distribution ?
You may order data on 4mm, 8mm, or 9-track magnetic tape, or electronically
for network transfer using File Transfer Protocol (FTP). You may choose to
receive your data in Unix Tar format if you like. Otherwise your data will
be in standard Unix DD format. The logical format of the data may vary
depending on the dataset. Many of the Goddard DAAC datasets are stored in
a standard format called Hierarchical Data Format (HDF), described in deatil
below. All data, regardless of the product, is accompanied by a README file
to help you use the data.
follow-up: What is HDF ?
Hierarchical Data Format (HDF) is a general purpose file structure that facilitates data sharing among people, projects, a computers on a network.
HDF allows information about the data in a file to be gathered from the
file itself rather than another source. It also provides a standard set of
tools to visualize and analyze the data. HDF documentation, source code and
libraries are available via FTP from NCSA at ftp.ncsa.uiuc.edu.Go into the
HDF directory and check out the README.FIRST file for more details.
How do I access data received from the Goddard DAAC ?
Every shipment of data sent out includes a README file describing the
physical format, or byte structure of the data file. Regardless of whether
data are sent out on magnetic tape of electronically via FTP, the README
file is copied to the tape as a separate file. In addition to data format
information, the README file may also contain sample read programs which
you can compile and run on your own computer.
What is the cost for data offered by the Goddard DAAC ?
All data and services offered by the Goddard DAAC are free.
What other on-line information services are available ?
The Goddard DAAC is one of eight Earth science archive centers comprising
the Earth Observing System Data Information System (EOSDIS). Some of these
centers offer a menu-driven search and order system similar to the Goddard
DAAC. In addition, there is a central information management system (called
the ESDIS IMS) that provides a central search and order service for data
held at all EOSDIS archive centers. The Global Change Master Directory (GCMD)
is a multidisciplinary database of information containing thousands of
descriptions of data products worldwide.
Where can I find data analysis software tools ?
The Goddard DAAC has developed an electronic library of software tools to
help you analyze science data. This library contains user-contributed
"freeware" donated by our users, and is accessible via anonymous the
Goddard DAAC anonymous FTP server. To obtain user-donated software tools,
log into our FTP server using the command:
ftp daac.gsfc.nasa.gov (or 192.107.190.139)
Name: anonymous
Password: (your e-mail address)
Go to the right directory by typing:
cd pub/contrib
OR Click on icon 
What if I want to actually visit the Goddard DAAC ?
The Goddard DAAC is located at the NASA Goddard Space Flight Center in
Greenbelt, MD. Our User Services office is in building 28, room N144. Our
staff will be happy to demonstrate our services to you or help you with any
questions you have. See the map of the Center for detailed directions.
How do I acknowledge the Goddard DAAC as a source of data and information used for a publication ?
If you are able to use data received from the Goddard DAAC in a publication
or presentation, the GSFC DAAC staff would appreciate receiving a copy of
your publication or its citation for our records and internal library.
This information is useful in tracking the data and in helping other
customers with similar needs and areas of interest. You can use the following
following acknowledgment in your publication :
"Science data provided by the EOS Distributed Active Archive Center (DAAC)
at NASA/Goddard Space Flight Center."
What types of products and services will the Goddard DAAC provide in
the future ?
As part of NASA's mission to planet Earth, the Goddard DAAC will archive
the data captured by the new instruments that will fly on the EOS polar
orbiting and Earth probe series of satellites beginning in 1996. We will
acquire more data on atmospheric total ozone, visible and infrared radiation,
clouds, precipitation, aerosols, land vegetation, ocean productivity,
atmospheric temperature, water vapor and other species profiles, and solar
irradiance,
