10/21/97 - Five scenes were added to the file. 10/09/97 - This readme files contains information about the following Humid Tropical Deforestation Project coverages that can be downloaded from our website: http://www.geog.umd.edu/tropical/main.html: This README file pertains to the file col8016k.v.1.e00.Z - 10/09/97 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> The file bolivia80.16k.v1.3.e00.Z will uncompress to 1.6 Meg. If you are operating on a Unix system type: prompt: uncompress col80.16k.v.1.e00.Z **Winzip should be able to uncompress this file also. To expand this file you will need to type the following at the Arc prompt; ARC: import grid col80.16k.v1.3.e00.Z This will create an Arc/Info grid ~1.5 Megs in size. **Note: If you are operating on a PC you will need to do a 'unix2dos' conversion on the col8016k.v.1.e00 before you attempt to import it into Arc/Info. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Coverages are being placed on the website as they are being finished. It is important to note that these are preliminary products. Field checking has been carried out in some areas, but is not complete. It is anticipated that revisions to this product will be progressively incorporated. Revisions will have higher version numbers. Details about the specific improvements in each version will be available as new versions are released. This ARC/INFO grid has a pixel size of 57 meters to a side. The output projection is Sinusoidal. An ARC 'describe' will list the relevant projection information, it is also included at the bottom of this file. The items within the .vat are defined below the class definitions. The main classes are: Class 1 Forest: Forest refers to primarily closed canopy humid tropical forest, and includes cloud forest. Class 2 Deforestation (80s epochs only.): Deforestation for the 90s will be calculated by comparing differences in the forest cover between epochs. Deforestation refers to areas of obvious human activity such as roads, cities, farms/ranches, and any other areas where forest coverage has been compromised. Class 3 Revegetation (80s epochs only.): Revegetation for the 90s will be calculated by comparing differences in the forest cover between epochs. Revegetation refers to areas where imagery indicates the presence of some type of vegetation that appears to be encroaching upon areas of human activity. These could indicate fallow fields, active agriculture, tree plantations, or secondary regrowth. Class 4 Water: Water includes lakes, rivers, and oceans if applicable. Water also includes areas that are inundated by dam/reservoir projects. Swamps may also appear as water. Class 5 Cloud: Cloud refers to areas where ground data is obscured or altered by cloud. Class 7: Undifferentiated Unforested: Undifferentiated Unforested areas may have been forest at one time, but were possibly deforested before the first data set reviewed by the NASA Landsat Pathfinder Humid Tropical Forest Inventory Project (i.e. pre-1972). These areas also include vegetation that may have a different spectral signature than areas considered to be forest, and require ground verification. Class 9: Nonforest: Nonforest includes areas such as cerrado, savanna, rock outcrops, high elevation brush/scrub vegetation, sand dunes or spits/bars, predominantly deciduous seasonal forest, snow fields, heavily inundated flood plains with sparse vegetation. Class 21: Questionable forest: Small areas, primarily in mountainous regions, that we believe are forest according to our definition but we need field validation to verify this. Class 91: Gallery forest: Where Gallery forests are (1) mapped inconsistently due to seasonality, image resolution (mss versus tm), and image quality and (2) the gallery forests are not contigious with the main forest, we have mapped them separately. Class 92: Gallery deforestation: Deforestation that is happening within the gallery forests. Class 93: Gallery revegetation: Revegetation that is happening within the gallery forests. Class 1xx: Forest under cloud: These areas are under cloud in the current epoch imagery, but by using additional later date scenes (the xx) we have verified that they are forest. For example, class 194 in the 80s coverage is cloud in the 80s image but has been verified as forest in a 1994 image. We only classify cloudy regions as 1xx if we can verify in the later imagery that they have not been deforested. Class 999/0: These are no data pixels where there was no good, cloud free imagery available. As we continue to search and obtain replacement data, future versions of the coverages will have areas of 999 replaced by the correct vegetation class. Areas of 0 are poor quality subareas within an image where we were unable to confidently determine the vegetation type. 16 KM Product: ---------------- The 80s epoch is being provided in a 16 KM(per grid cell side) resolution product. The 90s epoch data will be released in additional higher resolution formats. All percentages and area measurements are derived from the full resolution coverages. The file is the product of "export" from Arc/Info version 7.0.3 (copyright ESRI, Inc., Redlands, Ca). In order to display the .e00 file, you must first use Arc "import" to recreate the coverage. The usage is: Arc:import grid bolivia80.16k.v1.3.e00 Variables for each 16 km grid cell: Percent_1: The percentage of forest within the map cell. Percent_2: The percentage of deforestation within the map cell. Percent_3: The percentage of revegetation within the map cell. Percent_4: The percentage of water within the map cell. Percent_5: The percentage of cloud within the map cell. Percent_7: The percentage of undifferentiated unforested land. Percent_8: (Africa *ONLY*) The percentage of apparent human disturbance. Percent_9: The percentage of non-forest within the map cell. Percent_10: The percentage of combined deforestation/revegetation. Percent_91: The percentage of gallery forest within the map cell. Percent_92: The percentage of gallery deforestation within the map cell. Percent_93: The percentage of gallery revegetation within the map cell. Percent_1xx: The percentage of cloud turned to forest within the map cell, where the 'xx' represents the last 2 digits of the year that was used to verify the existence of forest. (EX. 191 is an area that was forest in 1991) Percent_999: The percentage of 999 in the map cell. 999 is 'Data not Available' Areas are calculated based on the pixel size (57 meters for 80s and 30 meters for 90s) and the number of pixels for a particular class within the map cell. Units are square meters. Forestarea: The area covered by humid tropical forest. Deforarea: The area of apparent deforestation. Revegarea: The area of apparent revegetation. Waterarea: The area occupied by water. Cloudarea: The area obscured by cloud cover. Undunfarea: The area of undifferentiated unforested land. Degforarea: *AFRICA ONLY* The area of apparent human caused forest degradation. Nonforarea: The area covered by non-forest vegetation. Combdefrev: The combined areas of deforestation and revegetation. GALFORAREA: The area of gallery forest GALDEFAREA: The area of gallery deforestation GALREVAREA: The area of gallery revegetation CLD1xxAREA: The area of replaced cloud (xx repesents the year) DATAUNAVAIL: The area of unavailable data *****Projection Information***** The Peru and Bolivia grids are in sinusoidal projection with: longitude of central meridian is -60 00 00 false easting is 3000000 M false northing is 3000000 M