Monday, March 30, 2009

Looking for LiDAR?

If you're in search of LiDAR data, I recently heard of a couple of sites that may be of use. The OpenTopography Portal is a useful site produced by the GEON Project. Here is information about the OpenTopograghy Portal from the site:

The OpenTopography Portal is a GEON Project initiative to build an online system that provides integrated access to high-resolution topographic data, web-based processing tools, and enables the user community to share knowledge, experiences and resources. ... If you have data you’d like to share, resources such as tools or documents to contribute, or are interested in collaborating, please contact us.

The OpenTopography Portal
In my day (!) these data were not available, and then as time went on, they were available for a steep price, so access to these high-resolution datasets is amazing. From the site:
Our goal is to use the OpenTopography Portal as a way to democratize access to high resolution topographic data and to allow users to share resources and knowledge.

Another site for LiDAR is the National Center for Airborne Laser Mapping or NCALM. There are helpful KMLs for selecting the data and site you're interested in. The range may be a bit limited but it may be worth checking out.

Thanks to Dave Tewksbury of Hamilton College and Peter Lea of Bowdoin College for posting about these sites.

Wednesday, March 25, 2009

Mapping for Humanitarian Aid

MapAction is a resource for humanitarian aid workers. Mapping during crises in order to get needed supplies in the right places is one of the missions of MapAction. Here is what they say:

"MapAction delivers information that saves lives and livelihoods. When disasters strike, coordinating relief efforts hinges on rapid transfer of information. MapAction delivers that vital situation information in the form of maps, created and distributed in the field. By conveying a "common operational picture", our maps make a crucial difference in delivering humanitarian aid to the right place to relieve suffering."


There is an updated Google Earth KMZ showing the locations and information of MapAction's missions (shown above).

They offer a PDF version of a field guide for GIS mapping called Field Guide to Humanitarian Mapping, that offers "step-by-step advice for aid workers who wish to use free and open-source resources to produce maps both at field and headquarters levels. " Access the mapping guide here.

Thanks, Caribean GIS blog for posting this.

Monday, March 23, 2009

Data Searches

List of GIS Data and Web Sites For Your Final Projects - GEOG 224

1. If you want to use US Census Data, keep in mind that the Sci Vis Lab and the GIS lab have a lot of useful 2000 Census data already loaded. These data are from the the Educational DVD distributed by ESRI. The shapefiles start with the 'educ_' identifier and come in polygons of state, county, tract, zip code, and blockgroup. (Look in this folder for the data C:\GIS_class\census2000)

Because there are over 1,000 demographic variables in the Educational dataset and almost all have cryptic short names, please take a look at the Excel file called "CommunityInfo Complete Layout.xls" to get an idea what the names mean. Be sure to click on the blue EDUC link in the Excel table (see the green circle below)

For instance, if you have a tract file open in ArcMap and you wonder what "HGRPL1_CY" means, go to the Excel table to see that it means "2004 HHs: Community LifeMode Group L1 (High Society)." You can ignore this category and should use variables that have a meaning you can understand.

I would go to the Excel table and find the data I was interested in mapping. For instance, "PCI00" is "2000 Per Capita Income" or "P00A15_19" is "2000 Total Population: Age 15-19" or "GQFES00" is "2000 Female Population in Group Quarters" Be sure to keep in mind that we have the data for EDUC only (look under Database Name in the table). If you want more 2000 US Census data you can go to the American Factfinder page.


2. The American FactFinder web site offers all the US Census Bureau data you could dream of.

Make sure you're on the data Download page and then click on the Summary File 1 (SF1) link and follow the directions. It's a bit of a tricky site to use but follow the steps and you should get the data you want for the geographic area you are interested in. The data are delivered as csv or xls, both should be readable in ArcMap. See this link for more information on working with those file types.


3. Now look at the right side of this blog, under Favorite Data Sources. You'll find some sites that I like to refer to.


Through the Vassar Library site, under Digital Map Collections, you can find some useful map sites including a link to the David Rumsey map collection where you can find many archival maps that are scanned and georectified.

Look at Free GIS Data & Imagery GeoBlog to get a quick idea of what's what, especially by location. Look at what he has for New Jersey.

The Geography Network offers a lot of freely downloadable data.

The GeoCommunity (GIS Data Depot) is a place to find international data. You need to register, but they do not spam you, or at least, they do not spam me.

State GIS data clearing houses are great places to get some local or regional data. Here is the link the the New York State GIS site. Or if you want another state, use Google. Countries may have rich GIS data sources, freely available, if you do a little searching.


4. If you want historical US Census data, go to National Historical Geographic Information System (NHGIS). Click on this link to get a step-by-step on how to use NHGIS site. Data go back to 1790.


5. The National Atlas Map Maker is another good site for spatial data.


6. Later in lab time, you will work with the USGS National Map Seamless dataset


7. Not Discussed in Class but perhaps still useful:

In ArcMap, go to Add Data (plus sign) and go to -> Look in -> GIS Servers. Add the Geography Network Server hosted by ESRI. Here you can load some data and I think you can download it. At the very least, you can use these data in your final maps and make analyses with the data sets. If you find something you'd like to download in one of these sets, send me an email and I can help you figure out how to get at the data.

Wednesday, March 11, 2009

Immigrant Population Map in the New York Times

The New York Times must be the place to be if you're a GIS specialist because the Times seems to have at least one new, amazing map a week. Yesterday they delivered the very usable Immigration Explorer - a web map that gives us census data going back to 1880 by U.S. county. The mapping was done with the aid of the Social Explorer, U.S. Census Bureau data.

This is a brief silent video that I made showing the use of the web map at Immigration Explorer. I did not make the map, I just used the Times' web site to make this video!



I think that the article linked to this map is here, but it seems perhaps that the Times is going to be discussing immigration in the future.

Thanks to my colleague Yu Zhou and Dave Tewksbury at Hamilton College for emailing about the map site.

Monday, March 09, 2009

Global Map of Travel Times and Accessibility

Expanding network of roads, low airfare, rail travel and shipping lanes help to generate the Time Travel to Major Cities map. From the European Commission Global Environment Monitoring website:

The map shows how accessible some parts of the world have become whilst other regions have remained isolated. Accessibility - whether it is to markets, schools, hospitals or water - is a precondition for the satisfaction of almost any economic need. Furthermore, accessibility is relevant at all levels, from local development to global trade and this map fills an important gap in our understanding of the spatial patterns of economic, physical and social connectivity.

The geospatial data, sources, software information (ArcGIS 9.2 and ArcView 3.x, and others) and more Travel Map information can be found here.

Thanks joguldi for Twittering about this project.

Friday, March 06, 2009

Geography of a Recession

The New York Times has done it again and given us an interactive map of the U.S. by county. The map shows unemployment rate by county and the relative change from last year. Alaska really stands out as being hard-hit by unemployment, as well as Michigan and the 'left coast.' This is the related article "Job Losses Show Breadth of Recession ."

Thanks, VerySpatial for the post.

Tuesday, March 03, 2009

Map Mashup By Journal Article Locations

There seems to be a map for all things, and articles in academic journals is not forgotten. Developed by Springer, AuthorMapper is a slick little Google Maps mashup that searches for papers by subject or location. Here's what they say:

AuthorMapper.com is a free interactive tool that visualizes scientific research areas and trends in an easy and refined way. It will assist the scientific research community by plotting authors, subjects and institutions on a world map as well as identifying scientific trends through timeline graphs, statistics and regions. Start mapping your scientific community today!

The search below is by 'geography' in which you find over 8,000 articles, the majority of them coming from the U.S and China


Beware: Though the map interface is 'free,' if you find an article you'd like to browse, you may find it locked out if your institution doesn't have a paid subscription.