
How much of reality are US citizens allowed to see? Can we make Google Earth into a three dimensional, searchable space that they can plug data sets into? Can this be done through an intuitive, beginner-level interface? Is it reasonable to expect all the information be recent -- not more than 3 months old, for instance?
Is it reasonable to expect that we all have access to the infrastructure of our communities? Do you trust yourself to walk along the shores of your local reservoir? Do you trust your kids with a computer-searchable, photo-accurate satellite map of your town?
How can government and corporate statistics be made more available and more visual? Is Adobe working on an application to gather and dramatically visualize data into quicktime movies and flash animation? Is somebody getting Christopher Alexander, Edward Tufte, Hans Rosling and William Gibson in the same room yet?
How much can joining be automated? Do we really need to fill out 10,000 profiles? Can we autojoin groups based on geotagged location? As the user, why should have have to start a profile, then go searching for local group? Obviously that's why the user is there. Make the obvious decisions automatic.
The first benefit of joining should be considerable: not "membership," not forum discussions, but a PDF report on their immediate ecosystem. Water quality reports, maps of water source proximity and purity, demographic reports and maps, detailed numbers on natural resources and economic history, lists of plants ideally suited to your climate, links to organizations already at work in your area with contact info.
I am curious about how to combine multiple datasets, and it's a testament to my GIS format ignorance that I don't even know how to phrase that question. Can I just dump MapPoint, Google Earth, USGS and Weather Service data together on a bad-ass computer and start looking for connections?
Data representation
GIS data represents real world objects (roads, land use, elevation) with digital data. Real world objects can be divided into two abstractions: discrete objects (a house) and continuous fields (rain fall amount or elevation). There are two broad methods used to store data in a GIS for both abstractions: Raster and Vector.
Raster
A raster data type is, in essence, any type of digital image represented in grids. Anyone who is familiar with digital photography will recognize the pixel as the smallest individual unit of an image. A combination of these pixels will create an image, distinct from the commonly used scalable vector graphics which are the basis of the vector model. While a digital image is concerned with the output as representation of reality, in a photograph or art transferred to computer, the raster data type will reflect an abstraction of reality. Aerial photos are one commonly used form of raster data, with only one purpose, to display a detailed image on a map or for the purposes of digitization. Other raster data sets will contain information regarding elevation, a DEM, or reflectance of a particular wavelength of light, LANDSAT.
Digital elevation model, map (image), and vector data
Raster data type consists of rows and columns of cells, with each cell storing a single value. Raster data can be images (raster images) with each pixel (or cell) containing a color value. Additional values recorded for each cell may be a discrete value, such as land use, a continuous value, such as temperature, or a null value if no data is available. While a raster cell stores a single value, it can be extended by using raster bands to represent RGB (red, green, blue) colors, colormaps (a mapping between a thematic code and RGB value), or an extended attribute table with one row for each unique cell value. The resolution of the raster data set is its cell width in ground units.
Raster data is stored in various formats; from a standard file-based structure of TIF, JPEG, etc. to binary large object (BLOB) data stored directly in a relational database management system (RDBMS) similar to other vector-based feature classes. Database storage, when properly indexed, typically allows for quicker retrieval of the raster data but can require storage of millions of significantly-sized records.
Vector
A simple vector map, using each of the vector elements: points for wells, lines for rivers, and a polygon for the lake.
In a GIS, geographical features are often expressed as vectors, by considering those features as geometrical shapes. Different geographical features are expressed by different types of geometry:
* Points
Zero-dimensional points are used for geographical features that can best be expressed by a single point reference; in other words, simple location. For example, the locations of wells, peak elevations, features of interest or trailheads. Points convey the least amount of information of these file types. Points can also be used to represent areas when displayed at a small scale. For example, cities on a map of the world would be represented by points rather than polygons. No measurements are possible with point features.
* Lines or polylines
One-dimensional lines or polylines are used for linear features such as rivers, roads, railroads, trails, and topographic lines. Again, as with point features, linear features displayed at a small scale will be represented as linear features rather than as a polygon. Line features can measure distance.
* Polygons
Two-dimensional polygons are used for geographical features that cover a particular area of the earth's surface. Such features may include lakes, park boundaries, buildings, city boundaries, or land uses. Polygons convey the most amount of information of the file types. Polygon features can measure perimeter and area.
Each of these geometries is linked to a row in a database that describes their attributes. For example, a database that describes lakes may contain a lake's depth, water quality, pollution level. This information can be used to make a map to describe a particular attribute of the dataset. For example, lakes could be coloured depending on level of pollution. Different geometries can also be compared. For example, the GIS could be used to identify all wells (point geometry) that are within 1-mile (1.6 km) of a lake (polygon geometry) that has a high level of pollution.
Vector features can be made to respect spatial integrity through the application of topology rules such as 'polygons must not overlap'. Vector data can also be used to represent continuously varying phenomena. Contour lines and triangulated irregular networks (TIN) are used to represent elevation or other continuously changing values. TINs record values at point locations, which are connected by lines to form an irregular mesh of triangles. The face of the triangles represent the terrain surface.
Advantages and disadvantages
There are advantages and disadvantages to using a raster or vector data model to represent reality. Raster datasets record a value for all points in the area covered which may require more storage space than representing data in a vector format that can store data only where needed. Raster data also allows easy implementation of overlay operations, which are more difficult with vector data. Vector data can be displayed as vector graphics used on traditional maps, whereas raster data will appear as an image that, depending on the resolution of the raster file, may have a blocky appearance for object boundaries. Vector data can be easier to register, scale, and re-project. This can simplify combining vector layers from different sources. Vector data is more compatible with relational database environments. They can be part of a relational table as a normal column and processed using a multitude of operators
The file size for vector data is usually much smaller for storage and sharing than raster data. Image or raster data can be 10 to 100 times larger than vector data depending on the resolution. Another advantage of vector data is that it is easy to update and maintain. For example, a new highway is added. The raster image will have to be completely reproduced, but the vector data, "roads," can be easily updated by adding the missing road segment. In addition, vector data allows much more analysis capability, especially for "networks" such as roads, power, rail, telecommunications, etc. For example, with vector data attributed with the characteristics of roads, ports, and airfields, allows the analyst to query for the best route or method of transportation. In the vector data, the analyst can query the data for the largest port with an airfield within 60 miles and a connecting road that is at least two lane highway. Raster data will not have all the characteristics of the features it displays.
Non-spatial data
Additional non-spatial data can also be stored along with the spatial data represented by the coordinates of a vector geometry or the position of a raster cell. In vector data, the additional data contains attributes of the feature. For example, a forest inventory polygon may also have an identifier value and information about tree species. In raster data the cell value can store attribute information, but it can also be used as an identifier that can relate to records in another table.
There is also software being developed to support spatial and non-spatial decision-making. In this software, the solutions to spatial problems are integrated with solutions to non-spatial problems. The end result it is hoped with these Flexible Spatial Decision-Making Support Systems (FSDSS)[9] will be that non experts can use GIS and spatial criteria with their other non spatial criteria to view solutions to multi-criteria problems that will support decision making.
I'm very new at mapping so excuse my ignorance if I'm totally off base.
I read this about getting SDTS DEM files on the USGS webpage:
1) The original DEM 7.5 minute tiled data available only in Spatial Data Transfer Standard (
And the reasoning for this is:
The decision to provide SDTS DEMs through the GIS Data Depot is consistent with the USGS goal of making more public domain data available at no charge while enabling the private sector to have a greater role in the distribution of USGS data. SDTS DEMs placed on media in response to customer orders will be sold by the GeoCommunity at a price less than the USGS currently charges.
Looking at datadepot, it costs $995 to buy SDTS DEM on CD for the entire USA. You can download it for free but you have to click a million links to do it and they don't allow web spiders to get the data automatically. It'll take months to manually download it all.
Looking at mapmart I can't see any clear way to get it for free.
And looking at ATDI-us you have to select a lat/long, again making it difficult to get the entire data set.
Can we just have a FTP server where we can get the entire lot? These private sector implementations are either very poorly implemented or purposely designed to make it very difficult to get the entire data set.
A USGS representative graciously took some time to provide a detailed response. It read as follows:
We greatly appreciate the comments and suggestions from the members of the list. Many of you have been around longer than me, and I've been a part of the list for about six years now. Your participation and suggestions have been a large part of why the SDTS DEM dataset remains an important and viable dataset. Thank you.
Although going through our commercial venders for SDTS DEMs may not always be the easiest or most efficient method, they do provide the data free of charge. It would have been great if the USGS was able to continue serving these data via USGS ftp site, but unfortunately we were not. Please keep in mind that commercial vendors are in business to make a profit. I, for one, greatly appreciate the time and effort put forth by our three venders, MapMart, GeoCommunity, and ATDI, to continue to offer USGS SDTS DEMs free of charge.
I'm not sure what the going rate is to host and maintain a server with several hundred gigabytes of data, and handling hundreds of thousands of file downloads in addition to providing monthly maintenance, but it must be substantial. [actually, the cost for such bandwidth coupled with applications developed using Open Source solutions are substantially less than now than when these arrangements were first setup so it really isn't that cost prohibitive?]
We welcome other entities to partner with the USGS in serving SDTS DEMs free of charge to the public, but for now, MapMart, GeoCommunity, and ATDI have been the only three to enter into an agreement with the USGS.
consider the Florida GIS Data Sharing Network (see http://groups.google.com/group/GIS-Data). This popular group brings together GIS professionals willing to share their data... what great idea! Think about it... you download or buy some DRGs, DEMs, DOQs, parcel data, or what have you. USing the list you can easily arrange to swap, share, exchange, or give away your GIS data needed by other professionals for their projects. To date the project appears to have been quite succesful and I'm actually quite surprised that other such cooperatives haven't popped up (if so, please tell me about it). For other data sharing cooperatives see http://www.gis-data.blogspot.com/ & a good example from Palm Beach County.
1:24,000 DEMs are easily available from the likes of the New Jersey State GIS Clearinghouse. These data are conveniently listed by USGS Quad name and as an added bonus, official FGDC metadata is also provided. Similarly, pretty much every other State clearinghouse has these data available, typically via FTP download... aka. grab what you need... woohoo! Look around and you'll likely find the data in .DEM format rather than the pesky native SDTS format
Users should also consult the Seamless data distribution system at http://seamless.usgs.gov where you can access the National Elevation Dataset (NED), in particular, the 1/3 arcscond data coverage. NED 1/3 arc second (~ 10 meter resolution) is processed and assembled the same as the NED 1 arc second, but the source data is 10 meter elevation data or higher resolution. Of interest, The coverage area is approximately 70% of the United States. There are 1/9 arcsecond data, however, the coverage is minimal. NED 1/9 arc second (~ 3 meter resolution)is processed and assembled the same as the NED 1 and 1/3 arc second, but the source data is using mostly LIDAR elevation data sources. Of note, the NED is derived from USGS DEM data.
Finally, another source that you absolutely MUST consult is the USDA Geospatial Gateway - home to NAIP ortho photography, DEMs, and a "whackin pant-load" of other spatial datasets - See http://datagateway.nrcs.usda.gov/GatewayHome.html

It turns out that the PS3 is ideal for doing precisely the kind of heavy computational lifting Khanna requires for his project, and the fact that it's a relatively open platform makes programming scientific applications feasible.
"The interest in the PS3 really was for two main reasons," explains Khanna, an assistant professor at the University of Massachusetts, Dartmouth who specializes in computational astrophysics. "One of those is that Sony did this remarkable thing of making the PS3 an open platform, so you can in fact run Linux on it and it doesn't control what you do."
He also says that the console's Cell processor, co-developed by Sony, IBM and Toshiba, can deliver massive amounts of power, comparable even to that of a supercomputer -- if you know how to optimize code and have a few extra consoles lying around that you can string together.
"The PS3/Linux combination offers a very attractive cost-performance solution whether the PS3s are distributed (like Sony and Stanford's Folding@home initiative) or clustered together (like Khanna's), says Sony's senior development manager of research and development, Noam Rimon.
Our community guide allows you to set up your own MPI (Message Passing Interface) based supercomputer cluster with the Playstation 3. This guide was co-written by Gaurav Khanna, based on his previous work on the Gravity Grid and is a current run-time environment for the research of co-author (Chris Poulin), based on his current work in distributed pattern recognition. As such, we currently utilize the Fedora Core for this infrastructure and illustrate a "how-to" below. NOTE: We focus on the Fedora 8 distribution, due to prevalence of Fedora and its Cell SDK (3.0) compatibility. Finally, this content should be considered open source, and here is the license.


Thanks for the inquiry. Our lab has two scanners. One a large flat scanner and the other a slide scanner. They are both manufactured by Microtek. We also have a server and three computer stations in the lab. Additionally, we have access to a classroom with approximately 30 terminals where we hold workshops and courses.
A plotter printer is vital for map printing. We have a 42 HP printer. Also, we have assorted Magellan GPS handhelds and one very nice Trimble GPS unit. As far as the software at the very least, you would need a high-end GIS program. We use ESRI v.9.2. I would also suggest Photoshop and the usual MS Office Suite to include Access and Excel. This should give you an idea of what you might need to get started. I hope this helps and please feel free to contact me if you have any other questions. In addition, you might try contacting UIUC or SIU and inquire as to their equipment/software. Thanks.
im not sure, but something of that sort would be really sweet. there are a lot of GIS tools out there. ArcGIS is a good place to start, and with enough practice you can get pretty efficient with it. I’m sure that there are tie-ins like that oriented toward permaculture and urban gardening and green geurillas kinda stuff. As a campus landscaper I was always proud to leave food plants hidden by folks when weeding. GIS would make those kind of operations a lot easier, especially when dealing with parks, rooftops, hidden nooks and crannies, etc. Its also great for planning urban and peri-urban foodsheds. I’m not super familiar with GIS but im sure many down geographers and ecologists/ environmental scientists about your town have some competence with the software.
As far as visualizing software in general goes, however, I would totally recomend Compendium for knowledge and concept mapping. Check it out and EcoSensus, where they integrate Udig, some software i dont yet understand.
I would totally agree that visualization is key and it will allow for people to better communicate across bioregions, manage resources, make decisions and plan and organize. The key is breaking with linear narratives and organizing information, ideas, arguments and concepts in ways that make more sense to us.
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