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    1. I downloaded the global level data file v2glp95ag.zip I looked into the file content on a unix system using 'more', and found most grid values to be less than 1. This is unexpected, as I expected the number of inhabitants per cell. What did I do wrong?

    2. Why was gROADS developed?

    3. What is the difference between "..ag"  and "...g" files?  For example, I've downloaded the population grid for the whole world for 1990, in "grid" format, and there are two sets of raster files.  When I open them in ArcGIS, they seem to show similar data, but the range of values for the raster is somewhat different: 0 to 1.24 million versus 1 to 1.17 million.

    4. After extracting all the data from GRUMP and adding up population by country to get country population totals, should the totals add up to match exactly the totals reported in the country summary?

    5. Monthly data

    6. I’ve downloaded the GRUMP 30 arc-second area grid (ASCII format), and am confused by the units. The meta data says that the units are km2 of land area, but when I unzip the file (using gunzip), producing gluareag_alpha1.asc, then the land cells have values of 56 (or less, if not completely land). Also, the missing value should be -9999 but the data file has 0 instead.

    7. On the "Prevalence of Child Malnutrition" data set using the 1/4 degree raster file called "UW", the values for the visualized raster data ranges from near 0 to over 500. But this does not make sense, because according to the documentation and the readme file, the "UW" file is supposed to represent the percent of children under age 5 who are malnutritioned. By that definition the values should only range from 0-100.

    8. I have imported the country-specific population density grid maps in ArcGIS for Argentina, Mexico and Honduras. I'm trying to join a table of points by latitude/longitude to these maps and export a table with all the data. The problem I'm having is that there does not seem to be any geographic data even though the maps are projected with WGS1984 correctly. I downloaded it from the site in the .bil format.

    9. Indian Rainfall Data

    10. ีupdated data

    11. Upgrade China Data  ·  completed

    12. Data Layers as REST

    13. Socioeconomic data for Alabama

    14. information about data encoding

    15. Geographical based searching for data  ·  under review

    16. Since the footprint data uses the spheroid GRS1980, can I just define it as NAD1983? I know that NAD1983 uses GRS1980, but I am not sure if I can define this layer as datum-based instead of spheroid-based.

    17. Accessing data from jupyterhub?

    18. We have downloaded the population estimate data for France (frap05ag.asc). When we use this file to calculate population for a given polygon, it does not match the response returned by the Population Estimation Service provided. We were wondering what is your criteria for including a grid cell in the calculation? Are you giving weight to a cell based on polygon intersection area? Also, wanted to clarify the xll, yll corner values - do the values -6, 40 represent the center of the bottom left cell or do they represent bottom left corner of the bottom left cell?

    19. numeric data for impervious surface areas

    20. Mangrove data errors

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