Coming in the following messages is the latest version of the Catalogue of Digital Elevation Data which I have been collating. Although primarily describing topographic and bathymetric data, there are a number of hopefully useful references to other forms of data. I know that there is data available for some countries yet have no, or only very sketchy, information. Also there are more question marks than I would like within existing entries. Any corrections / additions are always welcome via e-mail, and monthly re-posting will occur. Please send me ANY information you have, even if based on hearsay - other people will undoubtedly fill out the details - any clues are useful! ** CHANGES SINCE LAST MONTH ** o Ftp site for the USGS Data Users Guides was added under Note (3). o Corrections to details on French IGN data - Note (11). o Editing of Note (5) and addition of details on "Global Relief CD-ROM" o New Entry - Bavarian (German) data described in Note (36). ** ENHANCED ACCESS ** The most up-to-date version of this catalogue is always available through our mail server. Send e-mail to GEOINFO@GEOVAX.EDINBURGH.AC.UK for full details of how to use this service. The catalogue will also be available on a World Wide Web server here, the Universal Resource Locator (URL) for our home page is http://www.geo.ed.ac.uk/ ** GIS SOURCEBOOK ITEM ** Users of this list may be interested to know that the Digital Elevation Data Catalogue will appear in GIS World's International GIS Sourcebook 1995. I hope this enables more people to see the catalogue and results in new entries being sent to me. My main concern in allowing the catalogue to be published in this way was to make sure that the internet distribution not only continued but would be enhanced from the increased circulation. Thus the most up-to-date list will continue to appear here. Regards, Bruce Gittings """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" __ __ E D I N B U R G H E D / ) _ _ / ` ._/_/ . _ _ __ D I N B U R G H E D I /--< /`~/ / / )/_) / _. / / / / / )/ )( I N B U R G H E D I N /___/ / (_/ (_ (_ (__/ / / / / / /(_/__) N B U R G H E D I N B Dept. of Geography, Univ. of Edinburgh ._/ B U R G H E D I N B U Drummond Street, Edinburgh, EH8 9XP, Scotland. U R G H E D I N B U R E-mail: BRUCE@ED.AC.UK Phone: (0)31-650 2558 / 2543 Fax: (0)31-650 2524 """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" ##### Part 1 of the Digital Elevation Catalogue ##### CATALOGUE OF DIGITAL ELEVATION DATA LAST UPDATED: 13-AUG-1994 =================================== (c) Bruce M. Gittings, 1994. The following list is compiled on these basis of my own information and the contributions of a number of helpful readers of GIS-L. It includes details of elevation and bathymetric data. I would be very grateful for any corrections /additions, which you can be assured will be of benefit to the whole community. I am most grateful to the many individuals who have contributed. I have not acknowledged individual names because some have specifically wished to maintain their anonimity. If you supply me with material which, for one reason or another, should have a name attached I am happy to do this. Some additional information (eg. electronic documents which were the source of some of the information included here) are available by e-mailing our automatic information server (GEOINFO@GEOVAX.ED.AC.UK). Please read the copyright notice and disclaimer at the end of this message (if either of these are missing, then this posting is incomplete). REG NAME/SUPPLR SCALE/RESOLUTION VACm FORMAT SIZE COST/MEDIA/FTP NOTE --- ------------ ---------------- ---- ------ ------------ ---------------- ---- WOR DCW 1:1M as 1000ft ~650 VPF 600MB #200 (1) Cont & Spot Hgts /30 WOR EROS DCW-DEM 30" x 30" DEM <650 Binary ? Mag Tape & ftp (2) Only Part. Avail. Raster WOR Nat Geophys. FNOC Elev, Terrn 9 2 Byte 28MB On CD - see note (5) Data Center & Surf. Charact. Integers & via ftp from ? as 10 min Grid WOR Nat Geophys. ETOPO5 5 min DEM 9/1 2 Byte 18.5MB On CD - see note (5) Data Center Integers & via ftp WOR Hamilton 5 min DEM ? 2 Byte 18.5MB $1195 (35) Exploration Integers WOR Defense Map. 90m / 30m DEM 30 DTED-1 ~3MB per 1x1 Partial Release (6) Agency (DMA) degree tile only of 90m data WOR Global GRASS 4'48" Raster ? GRASS? ? $300 (npd) (8) Various Files WOR Dig. Bathym. 5' Raster Cells ? ? ? Low (!) (9) Database WOR GEBCO 1:10M / 1:1M ? MGD77, ? #99 for CD-ROM (10) Bathymetry DXF,GF3 WOR Axys Various ? QUIKMap ? ? (21) Software Ltd WOR MRJ Inc. Marine Data Sampler ? A/INFO <1 CD ? (npd) (28) ANT SCAR 1:200K to 1:5M ? PC A/INFO <1 CD #100 / CD (29) EUR Bartholomews 1:1M Contours/ ? A/INFO ? ~#4-500/ (npd) (34) Bathymetery country AST BEV 50m DEM ? ASCII ? ATS53/km2 (npd) (32) AUS AUSLIG Highest Pnt Grid ? ? ? ? (npd) (12) AUS AUSLIG Irregular Spot ? ? ? AU$100 / (npd) (12) Heights 1:250K sheet AUS AUSLIG 18" Grid of above 1 ASCII ? AU$150 / (npd) (12) 1:100K sheet AUS AGSO 6' (~11 Km) Grid 4-5 ? ? AU$750 (npd) (13) CAN EMR Canada 1:250K Contours ? IGraph ? CD$500 / (20 DGN map file &21) CAN Br. Columbia 1:250K DEM ? ASCII ? CD$230/sheet (26) CAN Br. Columbia 1:20000 DEM ? ? ? CD$600 (27) CAN Comm. Data ~93m (3sec) DEM ? Binary ? Depends on qty (25) Services Inc. (DoD) CAN Can. Hydrog. ? ? ? ? ? (23) Service CAN Can. Hydrog. 1:250K Great Lakes ? ? ? ? (24) Service/NOAA Bathym. Contours CHI SIIASA Contours ? A/INFO+ ? (npd) (14) I/G MGE FIN National 1:10 000 2-5 ASCII 750kB/5x5km2 100 FIM/5x5km2 (22) Land Survey 1:20 000 of Finland DEM 25x25 2-5 ERDAS, 1.50 FIM/km2 DISIMP DEM 50x50 2-5 Rodika 1.50 FIM/km2 FRA IGN 40m DEM (from 10 ASCII 350KB per 16800 FF / (11) 1:50K maps) /40 map sheet 1:50K sheet (npd) GER Bavaria 50/100/200m DEM 2-3 DXF,SQD ? 15DM/km.sq. (36) GER Hessen 40m grid or 2 ASCII $200/km.sq.(npd) (15) Province irreg. points IRE Bartholomews 1:500K Contours ? A/INFO ? ~ #400 (npd) (34) JPN SIIASA Contours ? A/INFO+ ? ? (npd) (14) I/G MGE JPN Geol. Survey 280x230m DEM ? ASCII 88shts x ? Free (18) JPN Geog. Survey 250m DEM ? ASCII ? Y9700/floppy (19) Institute (npd) JPN GSI 50m DEM ? ASCII ? Y9700/flpy (npd) (19) JPN GSI 1:25K Contours 3 ASCII ? $500/tape (npd) (19) JPN GSI 1:10K Point Heights ? ASCII ? Y9700/flpy (npd) (19) MEX Comm. Data ~93m (3sec) DEM ? Binary ? Depends on qty (25) Services Inc. (DoD) NOR Norwegian DEM 100x100m - lat 30 DTED-L1 ? Expensive (npd) (17) Map. Auth. -lon UTM Coords NZ DOSLI 1:50000 Contours 10 Various ? NZ$2000 (npd) (31) SAF CDSLI 50/200/400m DEM ~10 NES ? ? (npd) (7) SPA Inst. Cart. 45m DEM (100/200m >2 ASCII 95MB 6.25Pts/ (npd) (16) Catalunya also available) Hectare TWN - 100m DEM ? DTED 9 x 3MB Free (33) UK Ordnance 1:50000 DEM <3 NTF-L4 748KB per #30 p.a. (npd) (4) Survey 20x20km tile UK OS 1:50000 Contours 2-3 NTF-L1 ~1.5MB per #30 p.a. (npd) (4) 20x20km tile UK OS 1:10000 Contours ~1.5 NTF-L1 5x5Km tile } Special Order (4) UK OS 1:10000 DEM <2 Various 5x5km tile } (npd) UK Bartholomews 1:250K Contours ~10 A/INFO 70MB (total) ~#2850 p.a. (34) USA USGS 1 Deg ~93m (3sec) DEM <61 DEM ~940 x 9MB }$40 or less (3) USA USGS 30' ~62m (2sec) DEM ? DEM ? }(All this USGS USA USGS 15' ~62m x 93m DEM ? DEM ? } data same price) USA USGS 7.5' 30m DEM <15 DEM ~55,000x2MB }See Note (3) for ftp }sites for USGS data. USA NOAA/Canada 1:250K Great Lakes ? ? ? ? (24) Hydrog. Serv. Bathym. Contours USA Comm. Data ~93m (3sec) DEM <61 USGS 2 CDs $5000 (25) Services Inc. (same as USGS) DEM USA Hamilton Exp. USGS 7.5' Layers ? AutoCAD $80-160 / layer (35) - ESRI Inc. Various Data Sets - A/INFO - See Note (30) NB. DEM is used here to mean a regular gridded array of point heights REG = Region VACm= Vertical Accuracy in Metres WOR = World EUR = Europe ANT = Antarctica AST = Austria AUS = Australia GER = Germany MEX = Mexico CAN = Canada NOR = Norway CHI = China IRE = Ireland NZ = New Zealand FIN = Finland SAF = South Africa FRA = France JPN = Japan SPA = Spain TWN = Taiwan ' = Minute " = Second # = UK Pounds $ = US Dollars AU$ = Australian Dollars ATS = Austrian Shillings DM = Deutsch Marks FF = French Francs Pts = Spanish Pesetas CD$ = Canadian Dollars FIM = Finnish Marks Y = Japanese Yen NZ$ = New Zealand Dollars p.a. = per annum (ie. licence fee) (npd)= Not public domain - ie. commercial product, restricted use, not available via ftp. NOTES ===== (1) The Digital Chart of the World (DCW) was digitised under contract from the US Defense Mapping Agency (DMA) from their Operational Navigation Chart (ONC) series. These maps are at a scale of 1:1M (except over Antarctica where the scale is reduced to 1:2M). This is the largest scale unclassified map series that provides consistent, continuous global coverage of essential basemap features. It is composed of 17 thematic vector layers which include political boundaries, coastlines, cities, transportation networks, hydrography, landcover, hypsography and place names. DCW can be purchased from: UK/Europe: Chadwyck-Healey Ltd. Tel: (0223) 311479 Cambridge Place FAX: (0223) 66440 Cambridge CB2 1NR, UK. US: USGS Open-File Section Tel: (303) 236-7476 Box 25286 FAX: ? Denver, CO 80225, USA. DCW is distributed on FOUR CDs, with PC software to read the Vector Product Format (VPF). The size of the whole DCW database is approx. 1.6GB. The size of the hypsography is estimated at ~450MB. There is also some supplementary hypsography which is estimated at ~150MB. The individual 5 x 5 degree tiles vary greatly in terms of their data volume. The absolute accuracy of the DCW vector information is 2000m circular error (horizontal) and +/- 650m linear error (vertical) for the contours. The vertical accuracy for the spot heights is +/- 30m. All are at 90-percent confidence as defined by the US Defense Mapping Agency (DMA). The structure of the DCW database is based on the Vector Product Format (Military Standard - MILSTD 60006) and the Vector Relational Format (VRF) of the International Digital Geographic Exchange Standard (DIGEST). DCW is described by Military Specification (MIL-D-89009). Both MILSTD 60006 and MIL-D-89009 are available from: Standardization Document Order Desk Building 40 700 Robbins Avenue Philadelphia PA 19111-5094, USA. (2) The Digital Chart of the World (DCW) DEM data consists of a resampled array of regularly spaced elevations at intervals of 30-by-30 arc-seconds. (which is approximately 1km). The data have been generated using the ANUDEM program developed by the Australian National University and are at a resolution which is compatible with the Advanced Very High Resolution Radiometer (AVHRR) sensor. The horizontal datum is WGS84. Elevation values are expressed in feet above mean sea level. This data produced from the Defense Mapping Agency's (DMA) 1:1M scale DCW database using the contour line, point height and hydrology layers. Although the accuracy of these data has not been measured or calculated, they will be no more accurate than the DCW source (see Note (1) above for details). The EROS Data Center intends to generate this DEM data for the entire world to be distributed on CD-ROM as major geographic regions are completed. Production is under way for Africa. As of 1st June, 1993 the following areas are complete and available for distribution: Madagascar (S26 E43 x S11 E51) Haiti (Dominican Republic, Puerto Rico, Haiti - N15 W75 x N20 W65) These datasets are available at no cost over the internet via anonymous ftp from the EROS Data Center at Sioux Falls, South Dakota, USA. The address is edcftp.cr.usgs.gov (Numeric IP address is 152.61.192.70) and the data is in directory pub/data/30ASDCWDEM. The files are located under the sub- directories MADAGASCAR and HAITI. For those unfamiliar with anonymous ftp... (NB. Commands may vary slightly with differing ftp implementations) > ftp edcftp.cr.usgs.gov 220 dg3 FTP server (Version wu-2.4(3) Fri Apr 15 1994) ready. Name (EDCFTP.CR.USGS.GOV:bruce): anonymous 331 Guest login ok, send your complete e-mail address as password. Password: 230-This is the USGS/EROS Data Center anonymous FTP server. 230- 230 Guest login ok, access restrictions apply. ftp> cd /pub/data/30ASDCWDEM ftp> ls 150 Opening ASCII mode data connection for file list. MADAGASCAR HAITI ftp> cd HAITI ftp> get README The README file was the source document for this information and includes details of the data processing steps, algorithms used and detailed file formats. It is also available by sending email containing the text "SEND DCWDEM" to our information server (GEOINFO@GEOVAX.ED.AC.UK). The data are distributed as 16-bit straight raster image files in a latitude/longitude coordinate system. There are 4 ancillary files that accompany each image file. They contain the number of lines and samples of the image, geographic referencing information, and summary statistics. Note that the header file is appropriate for use with the Arc/Info Image Integrator. Files are named after the image with the following extensions: *.bil = image file *.bilw = world file *.hdr = header file *.stx = statistics file *.tik = coordinate file Note that to retrieve the image file you must switch ftp into "binary" mode. All of the other files are ASCII text. Thus you should use: ftp> binary ftp> get haiti.bil The Customer Services Section of the EROS Data Center will be able to provide up-to-date information about DCW DEM data availibility and areas that are in progress. They will also take orders for this data on unlabeled nine-track magnetic tape at a 1600 or 6250 bpi density. They can be contacted at: Customer Services Tel: (605) 594-6151 EROS Data Center FAX: (605) 594-6589 Mundt Federal Building Sioux Falls SD 57198, USA. (3) United States Geological Survey (the US national mapping agency) are at: Earth Science Information Center Tel: 1-800-USA-MAPS US Geological Survey (Continental US Only) 507 National Center (703) 860-6045/6336 (Others) Reston, VA 22092, USA. FAX: 1-703-648-5548/5939 The 7.5' (30m) DEM is derived either by digitising USGS 1:24000 scale quad maps (which gives less accurate results) or by scanning aerial photographs (now exclusively involving the National Aerial Photography Programme quad-centred photographs). Note that the vertical scale of the 7.5' DEMs may be in feet (in areas lower relief) or in metres (in areas of higher relief). The 7.5' DEMs are often not well edgematched as a result of being produced on the basis of individual map sheets. Significant gaps have been observed between quads. Data interpolation is really the only viable means of filling these gaps. Importantly the 7.5' DEMs are referenced to the UTM cartesian co-ordinate system, whereas all other USGS DEMs are referenced to geographical (latitude/logitude) co-ordinates. The 30' and 15' DEMs are closely related products for the continental US. Each 30' DEM is also available as four 15' DEMs. These products were produced either from digital contours obtained from maps between 1:24K and 1:100K scale or from resampling 7.5' DEMs. They are referenced to North American Datum of 1927 (NAD 27) or NAD 83. Elevations may be in metres or feet. Elevations located on the minute lines (all four sides) correspond with the same profiles on adjoining DEM blocks. The 15' DEM for Alaska is a different product where one DEM corresponds closely to a 1"/mile (1:63360) map sheet. The 1 Degree DEM provides coverage in one by one degree blocks and is available for all of the contiguous United States, Hawaii and Alaska. The data is derived by reformatting the Defense Mapping Agency (DMA) DTED Level 1 data, which was in turn taken from 1:250K maps and photogrammetric sources in the US. Thus see Note (6) for accuracy information. The 1 Degree DEM consists of a regular array of elevations referenced horizontally on the geographic coordinate (latitude/longitude) system of the World Geodetic System 1972 (WGS 72) or, for a few DEMs, the WGS 84 Datum. Note that the World Geodetic System is significantly different to the North American Datum (NAD) used to reference the 7.5' DEMs. Conversion is possible, buit is not trivial. Elevation data located on the degree lines (all four sides) correspond with the same profiles on adjoining DEM blocks. Elevations are in meters relative to mean sea level. Spacing of the elevations along and between each profile is 3 arc-seconds with 1201 elevations per profile. The only exception are DEMs in Alaska, where the spacing and number of elevations per profile varies depending on the latitudinal location of the DEM. Latitudes between 50 and 70 deg. north have spacings at 6 arc-seconds with 601 elevations per profile and latitudes greater than 70 deg. north have spacings at 9 arc-seconds with 401 elevations per profile. For a definitive description of the USGS DEM data and formats see the USGS Data Users Guide 5, "Digital Elevation Models". This document can be ordered, for a small fee, from the Earth Science Information Center at the address above. All of the USGS Data Users Guides (dealing with DEM, DLG, Land Use/Land Cover and Geographical Names data) together with standards documents for all of these data sets are available via anonymous ftp from nmdpow9.er.usgs.gov - details are in the file /public/readme.doc. Information about the 1 Degree DEM can also be found through the World Wide Web (WWW) at the following URL: http://edcwww.cr.usgs.gov/glis/hyper/guide/1_dgr_dem Complete coverage is available at 1 Degree, 30' and 15'. However, only approx. 50% of the US (not Alaska) is covered by the 7.5' (30m) sheets. The following is from a USGS report for FY93 and shows the numbers of quads which are currently available, with FY93 production following in brackets. DEM 27,585 (1,363) DLG - boundaries 17,369 (1,208) - PLSS 14,144 ( 805) - transportation 7,009 (1,093) - hydrography 6,765 ( 833) - hypsography 2,362 ( 507) - vegetation cover 1,506 ( 266) - non-veg surf cvr 1,477 ( 252) - survey control 1,488 ( 253) - manmade features 1,471 ( 294) DLG 100,000 30x30 min : - hydro-transport 3,611 ( 4) - boundaries 2,070 ( 341) - PLSS 1,432 ( 272) - hypsography 1,009 ( 375) LULC 517 DEM (1 Degree) 1,385 Complete coverage would extend to approx. 54,500 7.5' quads for the 48 states and Hawaii, and I believe approx. another 4,000 15' quads in Alaska. The USGS classifies DEM accuracy into three distinct levels as follows: Level 1 (Now photogrammetric source only) RMSE 15m, Absolute Maximum Error 50m. Most of the 7.5' DEMs (and all new ones) have a 7.5m RMSE. The older digitised 15m acccuracy DEMs will all eventually be replaced by those of greater accuracy. Level 2 (Edited Photo Source, Cartographic Source) - RMSE < 0.5 contour interval, Absolute Maximum Error < 1 contour interval. Level 3 (Cartographic Source) RMSE < 0.333 contour interval, Absolute Maximum Error < 0.666 contour interval Virtually all 7.5' data is classified Level 1 (a few are Level 2). All 30' DEMs derived from 7.5' data are also classified Level 1; all 30' DEMs dervied from contours are Level 2. All 1 Degree DEMs are classified Level 3. Remember that the 1 Degree DEMs are dervied from DMA DTED LEVEL-1 data, but the DMA use the term "level" to refer to spatial resolutions, whereas with USGS is is an accuracy measure. For all USGS DEMs the accuracy classification level is recorded within the DEM data structure. DEMs from USGS 1:100K scale maps are a few years away. The USGS have said they will not be working on these until the contour information is available in digital format (DLGs) for this map series. IMPORTANTLY, because USGS data is public-domain, files are available over the internet via anonymous ftp. A fairly good selection of DEM data (together with DLG, GNIS and much other data) is available from "spectrum.xerox.com". There are currently more than 65 7.5' (30m) DEMs. The DEM data are located in the directory "/pub/map/dem". For those unfamiliar with anonymous ftp... > ftp spectrum.xerox.com 220 spectrum FTP server (SunOS 4.1) ready. Name (SPECTRUM.XEROX.COM:bruce): anonymous 331 Guest login ok, send e-mail ident as password. Password: ftp> cd /pub/map/dem ftp> ls . . list of available files . ftp> get INDEX-DEM NB. Commands may vary slightly with differing ftp implementations. IMPORTANT FILES (that you should collect) for spectrum.xerox.com: INDEX-DEM - a list of the available DEM data NOTES-DEM - a description of the DEMs README-DEM - details of costs etc. of acquiring data from USGS (Other sites may use different names for the important index files if they are available). All of the 1 Degree (1:250K) DEMs are available via anonymous ftp from edcftp.cr.usgs.gov (Numeric IP address is 152.61.192.70). This ftp server is at the EROS Data Center in Sioux Falls, South Dakota. These data are encoded with the GNUzip compression program, although the server can automatically decompress the files as they are sent, but remember the transfer time will take a lot longer. The files average 1.75MB compressed but are around 8.8 MB once uncompressed. For the contiguous US the files are organised in directories (A-Z) that represents the first character of the name of the DEM. The file names are from the corresponding 1x2 deg 1:250K scale quadrangle map name with "_e" or "_w" appended for the east or west block. There is a simple index of these quadrangles available from GEOINFO@GEOVAX.ED.AC.UK as file USGS250K). The Alaskan files follow a similar structure but are in the sub-directory /Alaska. Note that the data files are stored on a robotic mass-storage device so there may be a short delay (~10 secs) while the media is retrieved. This server also holds DEMs produced from DCW (see Note (2) above). To access the parent collection of digital data at the EROS Data Center via the world wide web, connect to the following URL: http://sun1.cr.usgs.gov/eros-home.html The USGS have another FTP site called walrus.wr.usgs.gov, where there is some DEM data in the /pub directory. An additional source of the USGS One Degree DEMs is: CD ROM Inc., Tel: 303-526-7600 Golden, Colorado, USA The U.S. is covered on 6 CDs: CD 1 Longitude 64-83 W CD 2 Longitude 84-93 W CD 3 Longitude 94-101 W CD 4 Longitude 102-112 W CD 5 Longitude 113-160 W except Alaska CD 6 Alaska Prices are $495 for one CD, $1200 for CDs 1-5, $1566 for all six. This is substantially cheaper than the prices for the same data on tape from USGS, if you want complete coverage. Ftp access is likely to be most cost- effective if you have this facility. The USGS Lakewood Colorado Earth Science Information Center (ESIC) has a prototype US spatial data availability index, which includes details of available USGS DEMs, Digital Line Graphs (DLGs) and Land Use Land Cover (LULC) data. Other forms of data are also described, including geological maps. Indexes are updated on a monthly basis to provide the most current status of available US GeoData (information is intended to reflect more than just USGS data, although at the moment all data described in USGS data). These indexes are available via anonymous ftp (the operation of which is decribed earlier in this document) from the address greenwood.cr.usgs.gov (Numeric IP address is 136.177.48.5). The file INDEX, which describes the contents of the repository, should be picked up from the default directory; the index files are in the directory "/pub/esic", along with a useful "readme.txt" file. Note that these files can be large (the one containing the 7.5' and 15' DEM indices is >1.5MB) and will get even larger over time. Contact Eugene G. Ellis (gellis@usgs.gov) for further details or with problems. (4) Ordnance Survey (the UK national mapping agency) are at: Romsey Road Tel: (0703) 792300 Maybush FAX: (0703) 792324 Southampton SO9 4DH, UK. The 1:50000 scale Digital Height Data (OS term for both contours and DEM) is produced by the Directorate of Military Survey from contours (at a 10m vertical interval) on OS Landranger maps (1:50K). The contour data are in vector format and comprise contour lines, form lines, breaklines, lakes and coastlines, plus a selection of spot heights. Contours are provided at 10m elevation intervals and spot heights to the nearest metre. The DTM data consists of height values at each intersection of a 50m horizontal grid, the values have been mathematically interpreted from the contours on Landranger maps. Height values are rounded to the nearest metre, with those values over land being given the value of 1m. Heights are listed reading south-north from the south-west corner of the 20Km square at 50m intervals, giving 401 points to a column. This colmn is then succeeded by 400 columns. The total number of heights is therefore 160801. DTM accuracy is variable depending on the nature of the terrain; results have ranged been 2m in hilly rural areas and 3m in lowland urban areas. Both the 1:10000 Contour and DTM products are derived from the 1:10K map series contours (5m vertical interval but 10m in mountainous terrain). The contour data is in vector format, with height recorded as an attribute. The DTM data are available as an array of points at a user-defined spacing (typically 10m, but this may be relaxed in order to reduce storage requirements). The price of the product depends on whether the DTM is derived from contours alone or whether it is enhanced with other source information, such as high and low water marks, or levelled spot heights extracted from published large scale maps. The 1:10000 data is available to special order and can be tailored to specific user requirements. Data formats include NTF, OSTF (older Ordnance Survey Transfer Format), MOSS, DXF and Laserscan IFF. NTF is the UK National Transfer Format (now incorporated within British Standard BS7567). The OS are now distributing their data in NTF-2 (NTF Revision 2) which is *their interpretation* of BS7567. L1 is NTF Level 1, L4 is NTF Level 4 (levels are internal structures within NTF). Note that because the DEMs are derived from contour and not the other way round any contours generated from the DEM will not necessarily fit back onto the map sheet! I am told that the OS 1:50K DEM edge-matches "very well". (5) The 10' data was produced originally by the US Navy Fleet Numeric Oceanographic Center (FNOC) and consists of a 1080 x 2160 Geographic Grid (Lat / Long) containing Elevation (Max/Min/Mode to +/- 30 feet), Urban and Water Cover, Number and Direction of Ridges, Primary and Secondary Surface type (valley, lake, marsh, desert, ice-pack, low/avg/high/rugged mountains etc.). The 5' data (also known as ETOPO5) was originally produced by the Defense Mapping Agency (DMA) and consists of a 2160 x 4320 Geographic (Lat / Long) centroid-registered grid. It is a combination of 10' data expressed to the nearest 30 feet and 5' data expressed to the nearest metre. The ETOPO5 data has been placed on the walrus.wr.usgs.gov ftp server in the directory /pub/data. Logon as "anonymous" and give your email address as the password. There is a README file, and the dataset divided into the northern and southern hemispheres. The two files total 16.2MB in UNIX compressed format ('Z' files). Binary transfer is required. The ETOPO5 data can also be found in the /pub/doc/world/etopo5 directory on nic.funet.fi (this machine is in Finland). The 5' (ETOPO5) and 10' data-sets are available as part of the Global Ecosystems Database, produced by the National Geophysical Data Centre, on Compact Disk. This is designated "Disk A" and is intended to be the first of a set issued on an annual basis. The data are in a standard ISO 9600 CD-ROM format. The CD comes with DOS executable software (a subset of IDRISI) and includes export capabilities for UNIX users. Direct CD access from UNIX is possible but it will probably require format conversion. Available from: Global Ecosystems Database Project Tel: (303) 497-6125 National Geophysical Data Center FAX: (303) 497-6513 325 Broadway E/GC1 Boulder, CO 80303, USA Email: info@mail.ngdc.noaa.gov The ETOPO5 data base, the FNOC 10-minute gridded Modal height data for land masses and a gridded 30-second data base for the 48 contiguous United States from the US Geological Survey are all on the CD-ROM called the Global Relief CD-ROM. This may be a different version of ETOPO5 than contained on the Global Ecosystems CD-ROM mentioned above. Prepayment is required for this CD-ROM. The cost is $100 + $10 non-USA shipping. Credit cards are accepted with details transmitted by phone, FAX or email. Cheques should be made payable to "NOAA/National Geophysical Data Center". Further details from: NOAA/NGDC Tel: (303) 497-6338 325 Broadway E/GC4 FAX: (303) 497-6513 Boulder, CO 80303, USA (6) This is military data. Only some of the 90m data has been released and I understand that release has been suspended due to "sensitivity" of some components of the data-set. Further enquiries to: The Director Tel: (301) 227-2495 DMA Combat Support Center ATTN: PMA Washington, DC 20315-0010, USA They can supply "Digital Sample Set #1" which consists of eight cells of Digital Terrain Elevation Data Level 1 (DTED 1) for 43 N to 45 N 113W to 109W on 1600 or 6250 bpi, 9 track, 1/2" mag tape. Cost $600. This includes a copy of the DMA Product Specification. The Absolute Horizontal Accuracy is 130m circular error at 90% probability and the Absolute Vertical Accuracy is +/- 30 m linear error at 90% probability. The quoted size of the cells (~3Mb) is smaller in northern latitudes. (7) CDSLI is the Chief Directorate of Surveys and Land Information, the South African national mapping agency. They are located at: CDSLI, Tel: +27 21 685 4070 Private Bag X10, FAX: +27 21 689 1351 Mowbray, 7705, South Africa. 200m DEMs exist for about half the country (the more interesting areas), 400m DEMs exist for the rest of the country (the flat bits). CDSLI are starting to produce 50 metre DEMs as well. The absolute height accuracy of the 50m DEM is 2.5 metres, though this DEM is only available for the Cape Peninsula area and the Pretoria-Witwatersrand-Vaal area. During the 1994/5 financial year they intend creating a 50m DEM for the greater Durban area. Each DEM covers a quarter-degree square (to match the 1:50 000 national mapping series). They are on the Gauss Conformal projection on the Clarke 1880 (modified) ellipsoid. NES is the South African National Exchange Standard, copies of which are also available from CDSLI. (8) CD2 of the Global GRASS CD-ROMs contain the following files (amongst others); a bathymetry file, visual earth - shaded image file, a ridge systems file, a shaded relief map, a file containing major mountains of the world. The price for CD2 is US$300 (all three disks for $750). $10 required for shipping outside US, 25% reduction for US fedral agencies. These data are based on ETOPO5 (see above) but is in GRASS 4.0 format, however that is equivalent to Bit-Interleaved Pixel (BIP) format, which can be read into ARC/INFO GRID and other systems. For further details (eg. data sources) and an order form, send your FAX number or postal mailing address to: Cook College Remote Sensing Center, Global Dataset Project, Box 231, College Farm Road, Rutgers University, New Brunswick, NJ 08903, USA. Email: madry@deathstar.rutgers.edu (Scott Madry) (9) For the Digital Bathymetric Data Base, contact: Francis Marchan, Tel: (601) 688 4327 US Naval Oceanographic Office, Stennis Space Centre, Mississippi, 39522-5001, USA. (10) The GEBCO Digital Atlas covers the entire world. The main source was the 1:10M scale 5th Edition of the General Bathymetric Chart of the Oceans but there are large areas such as the Mediterranean and the South Atlantic which are based on scales up to 1:1M. The GEBCO Digital Atlas is available CD-ROM. It contains contours (the smallest contour interval is 100m), individually adjusted vector ship track data, special survey boxes, geographical names of undersea features, World Vector Shoreline and Tracks derived from the NGDC GEODAS dataset for comparison. Also included is a full suite of display and output software. This will provide output in DXF and GF3 formats. The CD-ROM costs 99 Pounds (+ VAT for European Union customers) and is available from: Dr Meirion Jones / Ms Pauline Weatherall Tel ? British Oceanographic Data Centre (BODC) FAX ? Proudman Oceanographic Laboratory Bidston Observatory Birkenhead Merseyside, L43 7RA UK. Email: BODC@unixa.nerc-bidston.ac.uk (11) The Institut Geographique National (IGN) are the French national mapping agency and their DEM data is available from: Mr. Lutrot, Tel: +33 1 43.98.85.01 Institut Geographique National, FAX: +33 1 43.98.85.05 Departement Grand Clients (Industrial Customers Dept), BP 68 - 2, Avenue Pasteur, 94160, St Mande, France. The DEMs are produced from a contour line database, by linear inter- polation. This database was built from 1:25000 map sheets (exceptionally from 1:10000 level) and for some areas directly extracted from aerial photographs at 1:60000 (mainly where the slope was too important so that extraction of contour lines from maps would lead to intersections). The basic coverage unit for these DEMs is the 1:50000 sheet (20 x 28 Km). They are distributed in a proprietary ASCII format on a restricted use basis. The scale is customizable (75m mean, min 50m, max 100m) from 1:25K and 1:50K. Derived DEMs are available (200m and over). The vertical accuracy varies with the data source - 10m from 1:25K maps, 40m from stereoplotting. Approximately 4 bytes are used per point stored. (12) Australian Data is available from the Australian Survey and Land Information Group (AUSLIG). There are three products; M7 are Critical Aeronautical Heights which represent the highest point in each 30'x30' quad, M8 are Spot heights (ie. an irregular grid) and M9 represents an 18" grid (gridded from M8 using an Hutchinson Algorithm). Both M8 and M9 have incomplete coverage of the country. AUSLIG are located at: PO Box 2, Tel: + 616 201 4340 Belconnen, ACT 2616, FAX: + 616 201 4381 Australia. (13) The Australian Geological Survey Organisation (AGSO - formerly BMR) provide a 6' grid of the whole country. AGSO are at: GPO Box 378, Tel: + 616 249 9111 Canberra, ACT 2601, FAX: + 616 248 8178 Australia. (14) Spatial Information Infrastructure for Asian Studies in Australia (SIIASA) is a consortium of 12 Australian universities lead by Griffith University. The aim is to establish GIS databases covering all of Asia, defined very broadly to encompass the Near East, the Pacific Islands (possibly including Papua New Guinea), and the ex-Soviet Central Asian Republics and Asiatic Russia in addition to South, Southeast, and East Asian Countries. The China GIS Project, established in 1989, is the pilot project for the SIIASA databases. Its 1:1,000,000 vectorised map of the People's Republic of China is nearing completion, and amounts approx. 0.5GB of data. In addition to elevations, dense hydrology, detailed transport routes and thousands of cities and towns, it includes an elaborate set of land use polygons covering the entire PRC. County-level administrative boundaries for the entire country, which will be used initially for the spatial analysis of 1990 census materials, are being extended back to October, 1949. Apart from China and Japan, the base map for the SIIASA spatial databases will be the 1:1M Digital Chart of the World, with larger scale spatial data incorporated where available and needed to service regional research interests. The digitising of China was started before the DCW became available. Japan was digitised because of deficiencies in the DCW data, particularly the contour information. Also 1000' contours were too sparse for some of the potential database applications in that country. Thus, contours in metres are being digitised for Japan at the following heights - some 20s and 50s, 100s, 200s, some 300s, 500s, some 700s, 1000s, and then upwards at 500 metre intervals. This digitising is almost finished. For all China there are spot elevations (in metres) that are somewhat less dense than those on the ONCs. For about a third of the country (mainly in the South-east) there is another set of spot elevations and contours at 25, ##### End of Part 1 of the Digital Elevation Catalogue (39925 bytes) ##### ##### Part 2 of the Digital Elevation Catalogue ##### 50, 200, 500, and then upwards at 500 metre intervals. The digitising of these sheets will take until the end of 1993. As soon as the other sheets of the "1:1,000,000 Map of China" has been published by the Xi'an Cartographic Publishing House (it is not known when this will happen), the remainder of the country will be completed. For further information and to access the data contact: Dr. Lawrence W. Crissman, Tel: (07) 875-7285 Asian and International Studies, FAX: (07) 875-5111 Griffith University, Email: CRISSMAN@ASIAN.GU.EDU.AU Nathan, QLD 4111, Australia. (15) For the German state of Hessen (Bundesland Hessen) the 'Landesver- messungsamt' provides a DEM. Its either a 40m grid or unprocessed irregular data with an accuracy down to 2m. Its price is approx. 200 Deutschmarks per Km2. Data comes on 3.5" disc or tape in tabular ASCII format from: Hessen Landesvermessungsamt, Tel: +49 611 535-0 Scharperstrasse 4, Postfach 3249, 6200 Wiesbaden 1, Germany. Other DEM-Data may be obtained from: Inst. fur Angew. Geodasie, Tel: +49 69 6333-1 Richard-Strauss-Allee 11, 6000 Frankfurt am Maine 70, Germany. (16) The Institut Cartografic de Catalunya has a DTM of the Catalonia region of Spain. The data is in grid format but it mostly comes from interpolation of a TIN (the TIN is not available). The data was captured from aerial photogrammetry at 1:22000 scale using analogue and analytical stereo- comparators. VACm depends on morphology for interpolated points and is difficult to establish but measured points are better than 2m. Price depends on resolution. The 1992 prices where: 45m DEM 6.25 Pesetas per Hectare (10000 square metres) 100m 1.25 Pesetas per Hectare 200m 0.35 Pesetas per Hectare (These prices are equivalent to 1.25 Pts per point) The whole of Catalonia has an area of 32000 sq. km., giving a maximum size of 95MB for the data. Orders should be sent to: The Director, Tel: (343) 218 87 58 Institut Cartografic de Catalunya, FAX: (343) 218 89 59 Balmes, 209-211 Telex: 98471 ICCB E 08006-Barcelona, Spain. (17) Norway, like all NATO countries, is covered by the DLMS (Digital Land Mass System) DTED elevation model. For Norway DTED is availiable in lat-long UTM coordinates (resolution of 100 by 100 meters). See also Note (6). For more information contact: Norwegian Mapping Authority, Tel: +47 321 18100 (Statens Kartverk), FAX: +47 321 18101 N-3500 Honefoss, Norway. (18) The Japanese Geological Survey offer a DEM as part of the Digital Geological Map of Japan on CD-ROM (released January 1993). Approx. 28MB of raster data includes the DEM, geology, faults, rivers, density and magnetic susceptibility of rock samples. There are approx. 88 raster mesh-maps, corresponding to one for each sheet in the 1:200000 map series for Japan. The resolution of each mesh is approximately 280m x 230m. This DEM is more accurate than can be generated from the Digital Chart of the World - see Note (1) - but less accurate than the GSI DEM data - see Note (19). Source code for a program to display these mesh-maps (on a NEC 9801 series personal computer - a curiosity found only in Japan) is included. The geological map itself is a digitised version of both the 2nd and 3rd editions of the 1:1M Geological Map of Japan, occupying approx. 52MB. Coast lines, geological units and fault lines are included and are stored in both DLG format and ARC/INFO 5.01 export format The coordinate system for all data is Lat/Lon. GSJ has a very open policy about data distribution and use. I believe the data is free to universities, government or non-profit organizations. Commercial users may be subject to a small fee. For further details contact: Dr. Norio Matsumoto Tel: +81 298-54-3643 Computer Geoscience Section FAX: +81 298-54-3643 Geological Survey of Japan Email: norio@gsj.go.jp Tokyo, Japan. (19) In conjunction with the National Land Agency, the Japanese Geographic Survey Institute (GSI) has been maintaining and providing limited access to digital geographic data since the late 1980's. Data includes coastlines, topography, landuse, administrative boundaries etc. at a scale of 1:25000 for total or near total national coverage. This data is called "Kokudo Suchi Joho" (National Digital Information) but its use is limited to governmental, academic and public organizations. The data is distributed on 1/2" magnetic tape. It has an open, fully documented (in Japanese) structure. Each tape costs about US$ 500. For more information see the article on GIS Activities in Japan, by T. Waza, in the 1993 GIS World Sourcebook (IBSN #0-9625063-2-X). In May 1993 the GSI introduced a series of "low" priced map data onto the Japanese market. There are now four distinct datasets available; vector at data at 1:25000 and 1:10000 and 50m and 250m DEMs. Please note that these new datasets are called "Kokudo Suchi Chizu" (National Digital Map) and should not be confused with the previously released "Kokudo Suchi Joho." The 1:25000 scale vector data covers the entire country in 86 datasets, arranged by 1:200K map sheets. The 1:25K data includes coastlines, rivers, lakes, administrative boundaries and text labels, but not height data! The 250m DEM covers the country in 88 data sets. This DEM has a cell size of 7.5" x 11.25" (approx. 250 m) which coincide with the 1:200K scale topographic maps. There are 320 rows and columns in each DEM. The 1:10000 scale vector data presently covers major urban areas and includes coastlines, rivers and lakes, a wider range of political boundaries than the 1:25K data, transportation features and point data representing important buildings and geodetic benchmarks. The geodetic benchmarks include National Geodetic Survey triangulation points, traverse points, regular benchmarks and spot elevation points. There are currently 213 sheets of the 1:10K data, of which 40 were completed in the last year. There are at least another 50 sheets currently in preparation. It is suggested that the 1:10000 data is in a different projection than the 1:25000 data. The 50m DEM has a cell size of 1.5" X 2.25" (approx. 50m) which coincides with the standard 1:25K scale topographic maps. There are 200 rows and columns in each DEM. The Z values are quoted to 1mm (somewhat over- accuracy?). Some 258 DEMs are currently available at this resolution. It is believed that this is the most accurate digital elevation data available for Japan. All data is in GSI's own ASCII format (vector or grid) which is documented with the data (in Japanese, but the format is not difficult to decipher). Character records are written using the Shift-JIS Codeset and contain kanji or double-byte character data. Datasets are distributed on either 3.5 or 5.25 inch high density floppy disks in MS-DOS format. Each disk costs JPY 9700, or about US$ 92. There is usually one map sheet or DEM per floppy disk, but this is not always the case. For example, with map sheets the number depends on data density. This Suchi Chizu data is available through the GSI's distribution centre: Japan Map Center Tel: +81 3-3485-5418 (Nihon Chizu Center) FAX: +81 3-3465-7689 4-9-6 Aoba-dai, Meguro-ku Tokyo 153, Japan. With regard to copyright or data reformatting issues, contact the Japan Map Center directly, in writing. GSI themselves are at: Geographic Survey Institute 305 Kitasato 1 Tsukuba-shi Ibaraki 305, Japan. For those interested in translating GSI data into ARC/INFO, a translator is available from PASCO the Japanese ARC/INFO distributor. Contact: Bai Yunshan Tel: 03-5351-5391 Systems Engineering Center FAX: 03-3370-7817 Pasco Corporation Tokyo, Japan. (20) Energy, Mines and Resources Canada produce digital maps at 1:250000 scale for all of Canada. Some areas available at 1:50,000 scale. The contact is Mike Sheppard at: Energy, Mines and Resources Canada Tel: (613) 995-4943 Canada Centre for Mapping 615 Booth Street Ottawa, Ontario Canada K1A 0E9. It is suggested that the EMR maps are not really in very good shape (they have been scanned and vectorized, but not much more). Some of the provinces (including British Columbia and Alberta) have cleaned up these maps and converted the contours into a DEM. To get these, it is necessary to contact each individual government (there are 10 provinces plus two territories), and some won't have them. See also Note (21) and (26) below. (21) This Canadian company redistributes data from the US Natonal Topographic Information Service (NATIS) in AXYS's own QUIKMap GIS format. These data come in four files: 1. Asia & South Pacific 2. Europe & Africa 3. South and Central America, Mexico & Antarctica 4. North America For more details contact: Axys Software Ltd. Tel: (604) 656-1922 P.O. Box 2219 FAX: (604) 656-4511 2045 Mills Road Sidney, British Columbia Canada V8L 3S8. The original NATIS files are available from: U.S. Department of Commerce Tel: (703) 482-5404 National Technical Information Service 5285 Port Road Springfield, VA 22161, USA. AXYS also has digital hydrographic charts of South & Central British Columbia. AXYS obtains digital data (not sure whether contours or DEM) from National Topographic Survey (NTS) in Canada for resale in AXYS's QuikMap format. I assume data are contours as a separate layer but not certain. The original NTS data is available from Energy, Mines & Resources Canada (Canada Centre for Mapping) at their address in Note (20) above. (22) The 25x25 and 50x50 metre products have the same source data (ie. 1:10000/ 1:20000 contours) but the interpolation method differs. The contours have been produced mostly at a scale of 1:10000 but a scale of 1:20000 is used in Lappland (Northern Finland). (The published topographic map is at a scale of 1:20000). In terms of formats; DISIMP is an Australian image processing package. Rodika is a special format that has been used for producing elevation data for Finnish Telecom. RAW means raw raster data without any headers. For more information contact: Tapio Siltala Tel: +358 0 154 5579 National Land Survey of Finland FAX: +358 0 154 5454 Geographic Data Centre Email: tapio.siltala@mmh.fi Opastinsilta 12 C P.O. Box 84 FIN-00521 Helsinki FINLAND (23) The Canadian Hydrographic Service has hydrographic and terrestrial digital maps at various scales. No further details are available at present. Canadian Hydrographic Service Tel: 613-998-4931 1675 Russell Road Ottawa, Ontario Canada K1G 3H6. (24) The Canadian Hydrographic Service and NOAA in the U.S. have embarked on a joint bathymetric mapping programme to cover the Great Lakes at a scale of 1:250000. These will be contour formatted maps. For further information there are two key contacts, one in each country. In the U.S. it is Troy Holcombe Tel: 303-497-6390 National Geophysical Data Centre NOAA FAX: 303-497-6513 325 Broadway Boulder, Colorado 80303-3328, USA. In Canada contact: John Warren Tel: 613-943-8049 Canadian Hydrographic Service FAX: 613-996-9053 615 Booth Street Ottawa, Ontario Canada K1A 0E6. (25) Communications Data Services, Inc. sells all Canadian 3 second data through a contract with Energy Mines & Resources Canada. They also sell Mexican 3 second data (whole country available). They have all these data in house and can distribute on CD-ROM, 8mm tape and via the internet. Prices depend on quantity. The Canadian & Mexican data are in a binary (DOD) file format. In addition, they have the standard USGS 3 second data. The whole country is available on 2 CD-ROMs, in the original USGS ASCII file format for $5000, in CDS's proprietary format (for the communications industry) for $4000. Alaska in USGS format is an additional $1500. They will also sell a minimum of 6 blocks. 30% discount is available for US Government Agencies and Universities. They are putting up an FTP server for "a few of the other things of interest we have found over the years". They have some sample Canadian data files which they are allowed to distribute freely. More details when this service is available. More information from: Rich Biby Tel: (703) 534-0034 Communications Data Services, Inc. (800) 441-0034 (US-Only) 6105-E Arlington Blvd FAX: (703) 534-7884 Falls Church, VA 22044, USA. Email: rich@comm-data.com (26) The government of the British Columbia province of Canada have taken the vector 1:250000 data from the federal government in Ottawa (EMR Canada, see Note (20)) and improved it. At this scale, 84 map sheets are required to cover the province. These sheets contain hydrography, transportation, utilities, contours, a DEM, and place names. The data are in UTM projection and the NAD83 datum, and are provdied with good documentation. These data are available from: MAPS-BC Tel: (604) 387-1441 Ministry of Environment, Lands and Parks Surveys and Resource Mapping Branch 4th Floor, 1802 Douglas Street Victoria, B.C. V8V 1X4 Canada. (27) There is another source of DEM data for the British Columbia province of Canada called TRIM (Terrain Resource Information Management). This a mapping project producing 1:20000 DEM maps. About 50% of the province is currently covered. Contact: Maps BC Tel: (604) 387-1441 Ministry of Lands and Parks Surveys and Resources Mapping Branch Parliament Buildings Victoria, B.C. V8V 1X4 Canada (28) MRJ Inc. sell a variety of marine data. This includes a Marine Data Sampler which covers all the oceans. Two areas are presented in more detail; the outer banks of North Carolina and Monterey Canyon off California. The sampler comes in Arc/Info format on UNIX or DOS format CD-ROMs. MRJ can provide customised marine data including bathymetry, ocean chemistry and climatological data. These data generally originate from government agencies. The resolution of bathymetry varies depending on geographic region. Global data are provided as points or 5-minute grids. MRJ can provide 15-second grid bathymetry for the US continental shelf. Sounding information is also available for many US coastal areas. Data are supplied on 1/2" tape and floppy disks. For further details contact: Susan McDonald Jampoler Tel: 703 385-0700 MRJ Inc. 10455 White Granite Drive Oakton VA 22124, USA. (29) The Antarctic Digital Database (ADD) represents the first seamless digital map of Antarctica. It includes the most up-to-date and complete coastline of the continent in digital form, together with a number of other data. The ADD, covering the area south of latitude 60S, has been prepared by the British Antarctic Survey (BAS), the Scott Polar Research Institute (SPRI) and the World Conservation Monitoring Centre (WCMC) under the auspices of the Scientific Committee on Antarctic Research (SCAR). The database has been compiled from maps published by 11 nations (Argentina, Australia, China, Germany, Japan, New Zealand, Norway, Poland, Russia, UK and USA). The scale of source material has ranged from 1:200K to 1:5M and the coastline has been up-dated using satellite imagery at 1:1M. All data are on the Polar Stereographic projection with a standard latitude of 71S, and a central meridian of 0. The coordinates are single precision (up to seven digits for each co-ordinate) and are in metres with the origin at the South Pole. The spheroid used is GRS80. The database includes a detailed dataset, comprising data at the original scale of the source material and data generalized to 1:1M scale. This contains most information published on medium-scale and smaller-scale maps of Antarctica. In addition there are generalized datasets at scales of 1:3M 1:10M and 1:30M. The data are subdivided into layers showing coastlines, cliffs, contours and elevation points, rock outcrops, faunal locations, glaciers, ice domes, glacier flowlines and margins, moraines, streams, lakes, place-names, research stations, major traverse routes, protected areas and historic monuments. The contours have a height attribute from which DEMs can be generated. The data is in PC Arc/Info format on a single MS-DOS formatted CD-ROM. Copies are available at GBP100.00 (US $150.00), including postage from: SCAR Secretariat Tel: (0223) 62061 Scott Polar Research Institute FAX: (0223) 336549 Lensfield Road Cambridge CB2 IER United Kingdom (30) ESRI (the vendors of the ARC/INFO GIS software) have a venture called the ArcData Publishing Program which aims to make data from third party publishers available to users of their software. These data sets are delivered in ARC/INFO-compatible format and include ARC/INFO coverages, attribute tables, images and surfaces. Topographic data includes DTMs, DEMs and contours. Data come from several sources, including satellite imagery, aerial photography and digitized contour maps and most are available in different projections and datums. The ArcData publishers offering these data will search their imagery archives to find optimal source stereopairs and acquisition dates to meet your needs. ArcData can be ordered via the individual suppliers or through: Desktop Order Center Tel: 909-793-2853 x2052 Environmental Systems Research 1-800-447-9778 (US Only) Institute (ESRI) Inc. Email: desktop@esri.com 380 New York Street Redlands CA 92373, USA. A (free) copy of the ArcData Catalogue can be obtained from the same address. The catalogue and further details of available data are also accessible through the internet via anonymous ftp to redlands.esri.com (198.102.62.1). Logon as "anonymous" and give your email address as the password. Look for the files "readme.txt" and "catalog.txt" (the latter is large) in the directory /pub/outgoing/arcdata. Details of the major suppliers of elevation data through the ArcData programme follow. 10m DEMs are available for any location in the world via SPOT stereoscopic satellite imagery. SPOT DEMs cover 60% - 100% of the full scene size of 60 x 60 km (~37 x 37 mi.) with a minimum of 820 sq. miles. Quarter-scene DTMs are also available. Data are supplied on media including exabyte, 1/2" tape and CD-ROM. For further details contact: SPOT Image Corporation Inc. Tel: 1-703-620 2200 1897 Preston White Drive FAX: 1-703-648 1813 Reston VA 22091-4368, USA. The headquarters of SPOT IMAGE is in France: SPOT IMAGE Tel: 33-61 53 99 76 BP 4359 FAX: 33-61 28 18 59 F-31030 Toulouse Cedex Telex: 532 079 F France. ERDAS can produce highly accurate DEMs and ortho-images from satellite imagery and aerial photographs. These are available in standard map sizes or can be tailored to meet specific needs. ERDAS digital ortho products are available worldwide in the UTM coordinate system, and for the United States in the State Plane coordinate system. Data are supplied on media including exabyte, 1/2" tape and possibly floppy disk. For further details contact: Product Services Manager Tel: (404) 248-9000 ERDAS Inc. FAX: (404) 248-9400 2801 Buford Highway Suite 300 Atlanta GA 30329-2137, USA. American Digital Cartography offer digital contour data digitised from USGS 1:24,000 scale contour separates for the entire USA delivered in 7.5 minute quadrangles. ADC also offer 1-Degree (1:250K) and 7.5 minute (1:24K) USGS DEMs and topographic contour data as part of their WorldMap(R) which is digitised largely from the DMA's 1:1M Operational Navigational Charts (ONC). Data are available on media which includes CD-ROM and floppy disks. For further details contact: American Digital Cartography Inc. Tel: (414) 733-6678 3003 W. College Avenue FAX: (414) 734-3375 Appleton WI 54914, USA. (31) A terrestrial digital elevation database of New Zealand is sold by the New Zealand Department of Survey and Land Information (DOSLI). The database is continuous and edgematched covering all of New Zealand except around Fiordland where modern mapping is yet to be completed. It is essentially created from the contours taken off the 1:50000 topographical maps, which have a 20m contour interval. The database is held as 3D lines fully quality assured. DOSLI generate DEM data on demand from this data source. The vertical accuracy of this database is given as 10m (which represents +/- half the contour interval). The xy accuracy is given as 22m. The DEM's are provided in user defined formats. A list of existing options is available if required. The data is released under licence and costs NZ$2000 for 1200 sq. km. plus NZ tax if purchased in NZ. DOSLI photogrammetrists will capture DEM data to higher accuracies on demand on fully recovered costs basis. Other data sets exist from smaller scale mapping but are usually only a subset of the larger scale mapping. For example, there is contour information available with a 100m interval. For further information contact: Geoff Howard Tel: 64 4 471 0380 Director Topographic Database FAX: 64 4 495 8450 Department of Survey Email: geoffh@dosli.govt.nz and Land Information Private Box 170 Wellington New Zealand. (32) A DEM covering all of Austria was produced in the late 1980's and this is currently being revised to improve quality. The source is photogrammetric N-S profiles (which were collected with the primary aim of orthophoto production). The original profile distance varies between 30 and 160m, but this was resampled to the resolution of 50m. The DEM is georeferenced to the Austrian National Grid (Bundesmeldenetz), which is a Gau-Krueger (Transverse Mercator) system covering all of Austria in three meridional sections. There are two ASCII formats available; either WINPUT (x,y,z) or DTMX (blocked "z" matrix), both of these are from the SCOP DTM software. Documentation is available. The data is available on diskettes, 9 track tape or Exabyte cartridges. The cost of ATS 53 per sq. km is subject to an additional handling fee of ATS 2000. The data can be ordered from: Bundesamt fuer Eich- Tel: +43-1-438935 und Vermessungswesen (BEV) FAX: +43-1-439992 (The Austrian National Mapping Agency) Ask for: Landesaufnahme "Gelaendehoehendatenbank" Krotenthallergasse 3 A-1080 Wien, Austria. (33) Todd Rothermel has created DTED files of the whole island of Taiwan, including some outlying islands. There are a total of 9 files, each one degree by one degree or 1201 x 1201 gridded values. The accuracy is good for 100m grid post spacing. Todd is happy to send these files to whoever may need them. He says he cannot guarantee accuracy and neither he nor his company take any responsibility for the use of these files. To obtain the files, or for further details, contact: Todd Rothermel Tel: 1-610-354-7299 Martin Marietta FAX: 1-610-962-2647 PO Box 8048 Email: rotherme@mdso.vf.ge.com Bldg 10 MS G Philadelphia, PA 19101, USA. (34) Bartholomews are at: 12 Duncan Street Tel: 031 667 9341 Edinburgh, EH9 1TA FAX: 031 662 4282 United Kingdom. Other formats (e.g. Atlas*Graphics, DXF) can be provided. The European 1:1M database now includes the European Union (EU) plus Scandanavia & Eastern Europe. Cost is #355 per small country to #492 for large countries. Prices for the whole of Europe are also available. Ireland is now part of the Europe 1:1M database, although actually captured at 1:500K and previously named Ireland 1:500K database. The Great Britain 1:250K Database (doesn't include Northern Ireland thus not the "UK" database - NI is part of the Ireland (now European database)) costs #2850 or #65 per 100km National Grid tile. Horizontal accuracy +/-200m. Vertical accuracy is approx. +/-10m - but depends on how you take account of horizontal displacements. Size 70mb in Arc/Info format. Discounts are normally available for educational establishments. For research and teaching (excluding commercial research) the data can be obtained at very low prices through CHEST at Manchester University Computing Centre (Tel: 061 275 6099). Higher education users in ALL European countries excluding the former Warsaw Pact area (for the time being) may obtain data through CHEST following a new deal. (35) Global land and seafloor elevations exist as a grid with a spacing of five arc minutes of latitude by five arc minutes of longitude. This data undoubtedly is a version of the ETOPO5 data described in Note (5). The complete data base is 9,400,000 grid values on magnetic tape. Data values are given as 16 bit integers. Each 8640 byte tape block contains all data values for a five minute band of latitude arranged in order of increasing eastward longitude. The data base contains 2160 blocks, starting at the North Pole of the Earth and stepping southward. Available as normal or VAX byte-swapped binary format. The data is available in binary or ASCII formats on 1600 or 6250 bpi magnetic tape at $1195. Also available in ASCII on IBM-formatted floppy disk as a 5 degree quad at 5 arc second resolution for $75 or a one degree quad at 12 arc second resolution for $195 (designate the SW corner of the required quad in each case). Data may be redistributed for non commercial purposes only. The following data are available for each USGS 7.5' quadrangle. Data is arranged and sold by layers. Files are in AutoCAD format. Data is under copyright. Basic roads.............. $80 Enhanced roads.......... $100 Double line roads....... $150 Geographic names......... $40 County Lines............. $80 Township Range and Section Lines... $80 Contours................ $160 Terrain Relief Grid..... $160 Quicksurf Compatible x,y,z ascii... $160 For further details contact: Hamilton Exploration Email: 3326954@MCIMail.com PO Box 5381 Virginia Beach Virginia 23455, USA. (36) The German state of Bayern (Bavaria) is currently implementing a topographic database called GEOGIS using Siemens Sicad GDB software. This will hold a variety of topographic layers and will be compatible with the German standard land information system ATKIS (Amtlich-Topographisch- Kartographische Informationssystem). The GEOGIS database is a vector database containing layers for topography geodetic/cartographic information, settlements, road infrastructure, water bodies and rivers, vegetation and administrative boundaries. Two GEOGIS datasets exist; GEOGIS-25 at 1:25K and GEOGIS-500 at 1:500K. Complete coverage is available of GEOGIS-500, produced from existing 1:500K maps. GEOGIS-25 layers are still being produced, with planned completion in 1996. The data source is 1:23K aerial photography. I have no details as to the form of the topographic layer (whether contours or spot heights) nor accuracy or size details. Data is generally in the Gauss-Krueger co-ordinate system and is available in either DXF, SICAD-SQD or (for GEOGIS-500 only) EDBS format. The GEOGIS-500 data is sold per layer for the whole of Bavaria, prices are 1000 DM for admin. boundaries and 3000 DM for water bodies/rivers. GEOGIS-25 data is sold by layer in sq. km. tiles; prices are between 1 and 3 DM per tile. The DEM (called DGM-25) is held at 50m resolution, but is also available at 100 and 200m. The data source was stereo-photogrammetery. The 50m data costs 15 DM per sq. km., the 100m data 5 DM/sq. km. and the 200m data 3 DM/sq. km. Another dataset which consist of 20m spaced points is also available (called DGM-5) at 65 DM per sq. km. Additional topographic data is also available as rasters at 1:25K, 1:50K and 1:100K. All prices quoted relate to May, 1993. The minimum order is for 300 DM. Further information from: Bayerisches Landesvermessungsamt Tel: +49 89 2129-1740 Alexandrastrasse 4 FAX: +49 89 2129-1537 D-80538 Munchen Germany. COPYRIGHT STATEMENT ------------------- (c) Bruce M. Gittings, 1994. Department of Geography, The University of Edinburgh, United Kingdom. The information contained herein may be freely distributed by any means provided that this copyright notice is retained. No other use is permitted without prior reference to the copyright holder. Specifically, this information may not be incorporated in any publication, document, report or manual which is sold or otherwise traded (whether for profit or not) or included as part of a package or product which is so sold or traded. DISCLAIMER ---------- The University of Edinburgh and I accept no responsibility for any errors in this list, nor do we endorse any of the data sets listed above in any way. I have no further information beyond that listed above, and am unable to help in either obtaining further details or acquiring the data themselves so please don't e-mail me requesting same! ##### End of Final Part of the Digital Elevation Catalogue (31815 bytes) ##### -- /======================================================================= | Bosco Tsang | Department of Geography, Hong Kong Baptist University | | 224 Waterloo Road, Kowloon, Hong Kong | | Phone: (852)339-7129, (852)339-7185 (direct) Fax: (852)338-6005 | |------------------------------ E-MAILS -------------------------------| | Campus (Main): btsang@ctsc.hkbc.hk GEOG Dept: btsang@geog.hkbc.hk | | CWOL-HKG (Co-SysOp, Geo*): bosco.tsang@f29.n700.z6.ftn.air.org | =======================================================================/ .