"Note:
Effective August 6, 2003, NOAA Atlas 2 has been superceded
by NOAA Atlas 14 for Arizona, Nevada, New Mexico, Utah and southeastern
California. Visit the Precipitation
Frequency Data Server for more information."
Welcome to the Hydrometeorological Design Studies Center web
page for
NOAA Atlas 2, the Precipitaiton-Frequency Atlas of
the Western United States, 1973. This web page provides access
to high-resolution (15-sec) NOAA Atlas 2 GIS rasters (grids)
for
7 states in the western U.S..
- The
GIS rasters can either be retrieved via HTTP
(web browser) or anonymous FTP.
- Please
read the
metadata and disclaimer
before making any use of these datasets.
- To obtain
the precipitation frequency estimates for 2-yr 6-hr, 2-yr
24-hr, 100-yr 6-hr, and 100-yr 24-hr at a given point, enter
the longitude (as a negative number) and latitude
in decimal degrees here: (enter 45° 30' 00'' as 45.500)
- To view
a scanned version of NOAA Atlas 2 for a specific state, please
visit our precipitation frequency
information page.
- To view
a complete set of scanned images of maps from NOAA Atlas 2,
visit the
*Western Regional Climate Center.
- These
spatial data sets are provided in an ArcInfo ASCII grid format.
This format is importable by ArcInfo (with asciigrid command),
ArcView 3.x Spatial Analyst extension or ArcGIS 8.x (ArcToolbox
function "ASCII to Grid"). If you don't have ArcInfo or ArcView
Spatial Analyst, you can visit the
*Geocommunity web page for list of free, fully functional
raster-based GIS mapping and viewing software. NOTE:
The links on this page are provided on this web page
as a convenience to users and does not imply endorsement by
or represent opinions of the U.S. Government.
- For
technical questions please contact Tye Parzybok at .
SEE METADATA |
Metadata -- "data about data."
A metadata file is available and may contain important information
about this spatial data set. We strongly recommend
that you read the
metadata file before making any use of these
datasets. (For information about metadata in general,
click here ) . |
HTTP Retrieval Information
Please
remember that spatial data files typically are very big! A 28.8K
modem, for example, takes about 10 minutes to download a 1 MByte
file, even longer if there's network traffic. Plan accordingly.
Downloading these files, which have a .gz suffix and
a ftp:// prefix, will cause your browser to either spawn a SaveAs
window or uncompress the file and display them. However, it is
best to save the file rather than view it on your screen. See
your browser's instructions on how to do this. You may use
anonymous ftp to retrieve files that are too large
to conveniently retrieve with a broswer, or to retrieve several
or all files at once.
FTP Retrieval
Information
Please
remember that spatial data files typically are very big! A 28.8K
modem, for example, takes about 10 minutes to download a 1 MByte
file, even longer if there's network traffic. Plan accordingly.
Clicking on files with a .gz suffix or ftp:// prefix
will cause your browser to make an "ftp" retrieval.
You will want to save this retrieval in a file rather than view
it on your screen. See your browser's instructions on how to do
this. You may use anonymous ftp to retrieve files that are too
large to conveniently retrieve with a broswer, or if you to retrieve
several or all files. Give the login name as
anonymous and your email-address as the password.
When transferring compressed files, remember to use the
binary transfer method.
For example,
to get na2_westus_100yr24hr.asc.gz and save it on
your computer, you would need to do the following from a prompt.
If using an FTP tool, you will use the same logic.
Action
|
Type
this |
Open
ftp to the server. |
ftp hdsc.nws.noaa.gov |
Login
as anonymous user. |
anonymous |
Give
the password, your email id. |
myemail@company.com |
Switch
to binary mode. |
bin |
Change
directory. |
cd pub/hdsc/data/westus/ |
Get
the file. |
get na2_westus_100yr24hr.asc.gz |
Optionally,
get other files. |
(whatever) |
Quit
ftp. |
quit |
NOAA Atlas
2 Domain