GuyNode. DEMs, Satellite imagery, topographic sheets, and other free rasters for Guyana.

Topographic Layers

Guyana

Geodetic Control

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	Current Datums and Coordinate System Provisional South American Datum 1956 (PSAD56). This datum is based on the International 24 Ellipsoid. The coordinate system is UTM Grid, Zones 20 and 21 North. WGS 1984. This is the ellipsoid used by the GPS system. Newer GIS maps may use this ellipsoid along with the UTM Grid, Zone 20 North and UTM Grid, Zone 21 North coordinate system.
	Geodetic Network PSAD56 Primary Controls. Thirty-one (31) Aerodist Stations established during the period 1967-1968, five of which are identical with Hiran Stations established previously as part of a South America Trilateration control survey of 1963. (Singh, undated). Secondary Networks (a) Inter American Geodetic Surveys 25 stations. (b) Directorate of Overseas Surveys (D.O.S); both Horizontal and Vertical Controls localised along the coastland (401 stations). (c) United Nations Development Programme (UNDP) – Horizontal Network - Timehri Airport to Eagle Mountain. (d) The 90 bench Marks located in the three (3) Towns that are part of the Guyana Water Authority Network. Benchmarks also exist along the coast. These are well defined and accessible. (Singh, undated). GPS Establishment in 2018 of a 8-station CORS Network based on the International Terrestrial Reference Frame (2014) datum. The CORS Network allows GPS data collected within a certain proximity of a station to be differentially corrected to yield centimeter-level coordinates. Click here to learn more about CORS.

Topographic Map Series

Series	Description
(1: 62,500 series).	1942. Covers coastal / near inland regions. 12 sheets. US military. Sheets not available to GuyNode
.	1943 (1: 125,000 series). Coastal / near inland regions. Produced by the British Directorate of Overseas Surveys (DOS)
	1959/1960s (1: 500,000 series). Country-wide Coverage. Produced by the British Directorate of Overseas Surveys (DOS)
	1950s/1960s (1: 50,000 series). Sheets produced for one-sixth of country. Sheets not available to GuyNode. Published by the British DOS.
1970s (1: 2,500 series)	Georgetown and other settlements. Published by the British Directorate of Overseas Surveys (DOS). Sheets not available to GuyNode
1976-1987 (1: 5,000 series)	G/town, New Amsterdam and Essequibo coast. 120 Sheets. (DOS 140M). Sheets not available to GuyNode.
	1981. 1:50,000 series. Near Country-wide coverage. Free sheets not available. Purchases can be made from East View Geospatial
1987-1990 (1: 50,000 series)	Coastal plain. 44 sheets. British Directorate of Overseas Surveys (DOS).
1964-1987 (1: 500,000 series)	10 sheets. Complete coverage. Soviet military. Sheets not available to GuyNode
1966-1990 (1: 1,000,000 series)	5 sheets. Complete coverage. Soviet military. Sheets not available to GuyNode
	Topographic paper maps are available for purchase from Guyana Lands and Surveys Commission. Ungeoreferenced, digital topographic maps can be bought here.

Digital Elevation Models

	Region 1, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 1. Source: 30-Meter SRTM Tile Downloader	(tif)
	Region 2, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 2. Source: 30-Meter SRTM Tile Downloader
	Region 3, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 3. Source: 30-Meter SRTM Tile Downloader
	Region 4, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 4. Source: 30-Meter SRTM Tile Downloader
	Region 5, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 5. Source: 30-Meter SRTM Tile Downloader
	Region 6, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 6 Source: 30-Meter SRTM Tile Downloader
	Region 7, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 7. Source: 30-Meter SRTM Tile Downloader
	Region 8, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 8. Source: 30-Meter SRTM Tile Downloader
	Region 9, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 9. Source: 30-Meter SRTM Tile Downloader
	Region 10, SRTM 30m Elevation Data SRTM digital elevation model clipped to the extent of Region 10. Source: 30-Meter SRTM Tile Downloader
	Aster DEM (Version 3) Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). Satellite-based collaboration between the USA and Japan that provides freely available global digital elevation dataset (GDEM) at a spatial resolution of approximately 30 meters. At a later date, GuyNode will download and clip ASTER DEMs by RDCs for Guyana. In the meantime, download from Earth Explorer Source: ASTER
	ALOS World 3D This dataset is a global digital surface model (DSM) with horizontal resolution of approximately 30 meters.
	Lidar Elevation Map of Georgetown (jpg). Raw LIDAR data appear not to be publicly available. Source: Final Report - Project, Georgetown
	Interactive Elevation Map of Guyana Map is centered on Georgetown, but elevation can be obtained for anywhere in Guyana. Source: https://en-us.topographic-map.com

Imagery

	Earth Explorer Satellite Imagery Global imagery for multiple years and platforms. Data must be downloaded and clipped to study area in Guyana. Source: Earth Explorer. This YouTube video provides instructions on how to download Landsat imagery and display different band combinations using ArcGIS Pro.
	Google Earth Engine Access more than more than forty years of historical imagery and scientific datasets, updated and expanded daily. Knowledge of how to work with the JavaScript or Python API is necessary . This YouTube video provides instructions on how to get started with Google Earth Engine.
	ESRI's Landsat Viewer View Landsat data online using ESRI's Landsat Viewer and Explorer app. You can also generate spectral and temporal profiles and perform various types of image analysis online. Source: Earth Explorer.
	Multiple Imagery Viewers Global imagery from multiple online imagery viewers. Provides good satellite view of Guyana at various levels of zoom. Source: Satellite Pro.
	Popular sites to download free imagery Source: Zoom into our Planet

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