Free electronic GIS maps of North America
Gary Noonan
carabid at CSD.UWM.EDU
Fri Mar 31 14:28:20 CST 1995
This announcement is about free electronic GIS files for
Canada and the United States. The files are designed for use in
Atlas GIS, but systematists probably can import them into other
GIS programs. The current file is called nam1a.zip and contains
electronic files for Canada and the United States. Additional
layers and files will be distributed by Internet as time permits.
The initial file can be obtained from the University of
Wisconsin-Milwaukee FTP server at ftp.csd.uwm.edu. Log on as
anonymous and change to the directory pub/carabid/GIS/NAM.
The directory currently contains nam1a.zip along with a read.gis
file that duplicates this message.
CONTENTS:
1. Background information
2. Providing proper credit for use of files
3. List of layers in present files
4. Feedback request
1. BACKGROUND INFORMATION
A recommendation of SYSTEMATICS AGENDA 2000 is
that systematists use GIS (geographical information systems)
programs to study geographical distributions of organisms. GIS
programs (such as Atlas GIS) make excellent maps for
publication and provide geographical analyses that are impossible
or extremely difficult without using GIS software. Examples of
such analyses include, obtaining the maximum area occupied by a
species, calculating the percent of such area overlapped by a
sister species, calculating the percent of such area once covered
by ice or permafrost during a previous glacial period, obtaining
total number of specimens or species found in a given elevation or
plant zone and calculating percent of species area covered by
various types of habitats. Additional examples and a review of
Atlas GIS will be found in the forthcoming volume 44, issue 2 of
Systematic Biology.
A major problem faced by systematists is that of obtaining
affordable electronic maps. The U.S. government provides map
data for the world in the Digital Chart of the World. The 1,600
megabyte DCW is distributed on a set of four CD-ROM disks.
Unfortunately, it's data are arranged in a Vector Product Format
not recognized by most GIS software and have to be exported and
converted into intermediate files that can be imported into GIS
software. Conversion requires obtaining a program for extracting
data from the CD-ROM disks and is difficult because the DCW
contains many data errors that interrupt conversion. And
conversion requires much time and large amounts of hard disk
space.
I used NSF grant funds to hire an assistant, David Uy, who
(with much help from Mitch Blank, Management Information
Specialist, at University of Wisconsin-Milwaukee) extracted data
in 5 degree tiles, converted data into an intermediate BIN format,
imported intermediate format into Atlas GIS, and merged
resulting map tiles into useful maps in Atlas GIS. The files are
for Canada and the United States (currently called nam1a) and
for Eurasia and northern Africa (currently called eur1a). Because
of limitations in hard disk space, the extracted files discarded all
but one vertex (for each feature) for every 1/20 of a degree. This
resulted in Atlas GIS files that were still very large, for example,
approximately 100 megabytes for Eurasia and northern Africa.
The resulting files have less resolution than in the original
Digital Chart of the World. However, that chart was created for
people who want to work on scales such as a portion of a county.
Most systematists work on continents or portions of continents.
The extracted files have more than enough resolution for this
purpose. Additional resolution in fact would slow down Atlas GIS
and would make difficult exporting maps into graphics programs.
The nam1a.zip file contains a subset of layers for Canada
and the United States, including those layers I found most useful
in my own research. This subset is relatively small in size. The
zipped file takes only 1.7 megabytes. When unzipped, the map
files take only about 3.8 megabytes. Additional layers will in time
be published via Internet. Files for Eurasia and northern Africa
also will be similarly made available.
The current files are ready for use in Atlas GIS. They were
prepared using the Windows version of this program. They can
also be used with the DOS version, but the program will have to
reindex them. Other GIS programs may possibly be able to import
Atlas GIS type files. When time permits, I will also release copies
of electronic files in an intermediate format suitable for importing
into a variety of GIS programs.
Users will probably immediately ask why elevations are in
feet rather than meters. The answer is that the Digital Chart of
the World has elevations in feet. 6000 feet is 1829 meters, and I'm
simply using in papers 1800 meters or higher as the description
of the 6000 feet or above region.
2. PROVIDING PROPER CREDIT FOR USE OF FILES
This material is based upon work supported by the
National Science Foundation under grant BSR-9104171, held by
G. R. Noonan. Any opinions, findings and conclusions or
recommendations expressed in this material are those of Noonan
and to not necessarily reflect the views of the National Science
Foundation.
The maps couldn't have been produced without the kind
assistance of Mitch Blank, GIS coordinator at the University of
Wisconsin-Milwaukee. He repeatedly solved problems in
extracting files and supervised students who worked to extract
data. Sumit Agarwal devised a program to work with the Digital
Chart of the World software to enable easy extraction of data.
Bugs in the DCW software made such extraction impossible.
Mitch Blank wrote an Unix based program for extracting data in
5 degree tiles and established procedures for correcting errors in
the data. David Uy subsequently extracted the data into
intermediate files, imported these files into Atlas GIS and merged
the 5 degree tiles into useful maps.
The proper citation for the file for use in materials and
methods sections or acknowledgments is: Noonan, G. R. 1995.
Milwaukee Public Museum map files for Canada and the U.S.,
with coastlines, 6000 and 8000 feet regions, Wisconsin glaciation
data, and major political boundaries. Ver. Nam1a. Based on data
extracted from U.S. Digital Chart of the World (1 vertex per 1/20
of a degree) and on digitized representations of Wisconsin
glaciation. Published via Internet.
The electronic files are copyrighted by the Milwaukee
Public Museum and should not be used in publications without
referencing the above citation.
3. LIST OF LAYERS IN PRESENT FILES
LAYERS in nam1a
Atlas GIS organizes map features into individual layers.
The display of layers can be turned on and off as desired. The
current file contains a subset of layers from the Digital Chart of
the World. Additional layers will be added as separate files in the
future. In the list of layers below, there is the layer name used in
Atlas GIS. There also is information from an Atlas GIS
description field for each layer. Some layers below have
additional descriptive information.
LcrossHairs. Description: Cross hairs, for aligning things Lines.
These cross hairs may be useful for aligning features during
various operations.
250kmgrid. Description: 250 km grid, Regions. This is a grid
composed of square cells, each 250 kilometers square. It
only should be used when a map is projected in an equal
area projection. The grid is useful in determining things
like centers of concentration of species.
6000ftsmall. Description: small, 6000 ft or above Regions. This
layer has small regions of 6000 or above feet. It's best to
leave this layer turned off unless your map is zoomed in to
a small area.
8000ftregion. Description: 8000 feet or above Regions. Layer
with regions of 8000 feet or above.
Appalach3000ft. Description: Appalachian Mountains at or
above 3000 ft, Region.
ArNMex6000ft. Description: Arizona, New Mexico 6000 ft and
above, Region. Mountains at or above 6000 feet in Arizona
and New Mexico.
Cal6000ftsmall. Description: California mountains at or above
6000 ft, Region. Miscellaneous small California mountains
at or above 6000 feet.
Cascades6000ft. Description: Cascades mountains at or above
6000 ft., Region. Part of these mountains, showing
mountains in British Columbia, Washington and northern
California.
CascadesMany. Description: Cascades Mountains, most of these
mts.,Regions above 6000 ft. Layer with most of the
Cascades Mountains of 6000 or above feet.
NearWiscIce. Description: Wisconsin maximum glaciation,
Region. Shows Wisconsin maximum glaciers, doesn't show
permafrost and montane glaciers. The information in this
layer was added with a digitizing tablet based on references
cited in Noonan G. R. 1990. Biogeographical patterns of
north American Harpalus Latreille (Insecta: Coleoptera:
Carabidae). Journal of Biogeography, 17:583-614.
NearWisPErmafr. Description: Wisconsin permafrost found=7F
south of maximum glaciation, doesn't show glaciers, Region.
he information in this layer was added with a digitizing
tablet based on references cited in Noonan G. R. 1990.
Biogeographical patterns of north American Harpalus
Latreille (Insecta: Coleoptera: Carabidae). Journal of
Biogeography, 17:583-614.
Nevada6000ft. Description: Nevada mts. at or above 6000 ft.,
Region
SCanMtRockies Description: Rocky mts. at or above 6000 ft.,
S.Canada & Montana, Region. This is a subset of the
Nrockies layer.
Nrockies.. Description: Northern Rockies, 6000 ft. or above, Can.
N.Mont. Region. The northern Rocky Mountains at or above
6000 feet in Canada and northern Montana.
NW6000ftsmall. Description: misc.6000 ft. >=3D mts. WA, N.Or,
Id., sBC, EMont., Region. Miscellaneous small mountains
at or above 6000 feet in Washington, northern Oregon,
Idaho, southern British Columbia and eastern Montana.
NECalNev6000ft. Description: NE Calif. N. Nevada, >=3D 6000
feet, Region. Mountains at or above 6000 feet in
northeastern California and northern Nevada.
SWBCol6000. Description: SW British Columbia mountains >=3D
6000 ft., Region. British Columbia southwestern mountains
at or above 6000 ft. Layer shows small mountains
separately.
Rockies6000ft. Description: Rocky Mts. >=3D 6000 ft., main
portion, Region. Main portion of Rocky Mountains at or
above 6000 feet.
SdakWyom6000ft. Description: South Dakota, Wyoming mts =3D>
6000 ft, Region. Black Hills of South Dakota and 3 small
mountains in northeastern Wyoming, regions at or above
6000 feet.
UTCOL6000ft. Description: Utah, W. Colorado mts. >=3D 6000 ft.,
Region. Mountains in western Colorado and Utah above or
at 6000 feet.
WisGlacFrost. Description: Wisc. glaciers, permafrost, Region.
Layer shows maximum Wisconsin glaciers, permafrost and
montane glaciers. he information in this layer was added
with a digitizing tablet based on references cited in Noonan
G. R. 1990. Biogeographical patterns of north American
Harpalus Latreille (Insecta: Coleoptera: Carabidae).
Journal of Biogeography, 17:583-614.
WisAlpFrost. Description: Wisconsin montane or alpine frost
during Wisconsin, Region. Layer shows the montane or
alpine frost areas during maximum Wisconsin glaciation.=7F
This is a subset of WisGlacFrost. he information in this
layer was added with a digitizing tablet based on references
cited in Noonan G. R. 1990. Biogeographical patterns of
north American Harpalus Latreille (Insecta: Coleoptera:
Carabidae). Journal of Biogeography, 17:583-614.
WyomingBasin. Description: Wyoming & other low lying basins.
These relatively low basins divide the Rocky Mountains,
and are basically high desert.
hyl5000. Description: Lines, 5000 ft or above. These lines need to
be checked, open spots closed as needed, and then can be
copied feature by feature into a new region layer to show
regions of 5,000 feet or above elevation.
polCoastline. Description: Lines, showing coastlines. Layer
shows coastlines of continent.
polDejure_inte. Description: International boundaries, lines.
Has international boundaries, such as those between
Canada and the U.S. and Mexico and the U.S.
LatLongrid. Description: lat, lon, grid, in 5 degree tiles, old pol-
Political layer. This layer has a latitude and longitude grid
in 5 degree increments. The Digital Chart of the World
called this layer pol-Political.
polPrimary_adm. Description: State, province boundaries,
Lines. This layer has the boundaries between states and
provinces.
SierraNev6000ft. Description: Sierra Nevada mts. >=3D 6000
ft.Cal.Nev.,Region. This layer shows the Sierra Nevada
mountains at or above 6000 feet. These mountains occur in
eastern California and western Nevada.
6000ftcontinent. Description: mts. =3D>6000 ft. This layer shows
regions of 6000 feet or above and contains all but a few very
small mountains. It has most of the 6000 feet regions listed
above incorporated into it.
4. Feedback request.
I've put effort into making these maps available and would
appreciate both positive and negative feedback. If you find these
maps helpful, please let me know via E-mail. Also please me
know what additional layers or data will be useful. Please put
nam1a in the subject line of any E-mail messages about the maps.
My E-mail address is carabid at alpha1.csd.uwm.edu
Thanks, Gary Noonan
=
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***
* Gary Noonan, Curator of Insects, Milwaukee Public Museum, 800 W. Wells =
*
* Milwaukee, Wisconsin 53233 USA and Adjunct Associate Professor of=
Zoology *
* University of Wisconsin-Milwaukee =
*
* carabid at alpha1.csd.uwm.edu voice (414) 278-2762 fax (414) 223-1396
*
****************************************************************************=
**
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