Sunday, November 18, 2012

Web Map Publishing Update

A few pieces of news related to publishing maps online.  Open Layers 3 is expected to be developed according to a blog post.  Be sure to check out MapBox for another great way to publish maps online.  Like other publishers, they have tiered pricing system starting at free.  Also download TileMill an opensource map design program. Unfortunately, I have been very busy but hope to a have few new maps in the next few weeks. Click the screenshot below for a more detailed look.

TileMill Tutorial Screenshot

Sunday, October 21, 2012

'Continuing the Landsat Legacy'

Barring anything unforeseen, the next Landsat satellite should liftoff in early 2013.  NASA has an interesting Twitter page of announcements and opportunities for the wide range of its users. In addition, a recent full free issue of Remote Sensing and the Environment contained lots of articles about the exciting past, present and, future of the Landsat program. A cool brochure is also available. Be sure to check it out! When it comes to free data, Landsat has to come to your mind! 

Comparison of Landsat Satellites -- What's Ahead... (Click on the Image to Enlarge)

Friday, September 21, 2012

iOS 6 Maps and Criticism

Apple has recently updated its mobile operating system, iOS 6.  One of the major changes includes an overhaul of its map app, which has not gone well.  You can check out a few examples here:  The current map app is based on data from TomTom, OpenStreetMap, and others.  The former app was based on Google Maps.

Despite the current issues, the maps will be an improvement, lightweight, have pleasing cartography, and incorporating data from businesses, etc. Some important features are missing but will be included in the near future.  You can also read Apple's response here.

Sunday, September 16, 2012

Opticks Update in October

Earlier, I wrote a little about Opticks, an open source image analysis program.  It also features python extensions for added capabilities and programmability.  The Opticks team is headed towards another release--in October.  The timeline for releases is always well laid out, as well as what has been changed, updated, or improved.  Unlike many other open source programs, new Opticks versions are released several time per year.  Opticks also has a great file importer especially since there are numerous file types out there.  So, be sure to check out Opticks!

Screenshot of Opticks - Showing the Data Importer (Click image for a larger version)

Monday, August 27, 2012

The Problems with Election Maps

With the presidential election on a few months away, maps of the potential outcomes have already started appearing.  Electoral college aside, the flaw with these maps is obvious--no state is all for one candidate or the other. Just looking at one map, makes me think popular vote!

CNN's map and calculator will even let you see what happens if all states went Democratic or Republican: What the use in an all red or blue map?  Even worse, is Amazon's 'heat map' of whether people are purchasing 'red' or 'blue' blooks, indicated by a percent greater than 50%.  Essentially the entire U.S. is symbolized in red. No map is preferable to a bad map.

On the other hand, The New York Times, does a better job: using a cartogram to symbolize the number of electoral votes per state.  Then population and its associated number of votes is the focus rather than the number and size of states, which can be deceiving.   In fact, as some posts suggest, the potential outcome, and margin of victory, may be better conveyed in a graph looking back historically.  Sadly, many consumers probably don't look at the NY Times map or find it difficult to understand.  Wikipedia also tackles the issue of map interpretation and the electoral college.

Lastly, the Huffington Post goes a bit further by including a handy historical table with its basic map--that way people can see which states are traditionally red, blue, or teetering on the edge.  Finally, it is important to mention that other maps, such as turnout rates, would also be helpful but are rarely seen or talked about in the news and media.
Source: New York Times, Click to bring up a larger version

Thursday, August 23, 2012 (OSM) provides users the ability to edit and download street maps for free through open source licensing.  Check out more background information about OSM at Wikipedia.

Open source GIS software like QGIS also have add-ons to aid in the download process. Alternatively, you can download the data directly from its website or connect to a WMS server.  You can also use OSM maps as base layers in Open Layers for web publishing.

Companies, including Apple, have recognized OSM's value--Apple uses OSM in its iPhoto app.  Most of the map's symbology is relatively straightfoward, but you can also check out its wiki to find an extensive list.  Below the Florida keys are shown. Click the photo for a more detailed image.  Be sure to check out this terrific resource!

The Florida Keys

Wednesday, August 8, 2012

Remote Sensing and GIS That Are Out of This World!

Image: NASA/JPL/University of Arizona "Serpent Dust Devil of Mars"

It is easy to forget a lot of remote and direct sensing, GIS and GPS work, and measurements are not even done on Earth.  Of course, I am referring to NASA's Curiosity Rover that touched down this week and the Mars Reconnaissance Orbiter (MRO) which has been in orbit for several years.  These are following in the footsteps of other great rovers and spacecraft that have successfully made the voyage.  However, I feel like the MRO is a bit neglected...

The MRO carries a host of sensors and instruments to map and image Mars including, A high-resolution camera in visible wavelengths (HiRISE), a wide area view camera, a weather imager in five visible and two ultraviolet bands (MARCI), an infrared spectrometer looking for signs of water, mineral deposits, etc., a radiometer, and a radar (SHARAD).

The scientific value of these instruments is beyond measure. NASA is probably one of the best agencies at making data and images available publically...Here are some neat open source resources related to this endeavour!

Tuesday, July 24, 2012

Meograph - Telling Stories with Maps

Maps are frequently used as storytelling devices.  However, relatively few tools exist to facilitate the transition from a map to a story.  Meograph, which is in its beta form, provides a platform to merge the 'where' of a story with media such as videos and photographs.

Time is also an important fourth dimension here.  Meograph makes it easy for authors to progress through their stories from one date and time to the next.  Watch the Meograph Demo of the Treyvon Martin Case for an example of how compelling such melding of media and geography can be.  Narration can also be added by anyone.

Meograph is very polished and easy to use.  I created a rough draft short story of the Derecho Storm here:  Spatially, there are a couple of stories that could be told. I need to create better locations for storytelling.  Most importantly, although a draft, what was created was done quickly and looks good. I will work on my Meograph and we will revisit it later.

Bottom line: Creating a smooth coherent spatial story with media in Meograph is far easier than with any desktop GIS program.  Hopefully, all that time saved from creating animations will help you tell a better story.  With a quick click, your meograph can be shared through social media or embedded.

Friday, July 20, 2012

Non-GIS Open Source, Worthy Companions

Do not look at the title twice!  Yes, this post is about non-GIS open source software.  However, these open-source programs make great companions to any analysis. 

For example, you may find the need for a traditional statistical software package. R Statistical Software can aid in importing, analyzing, and cleaning your data.  You can perform traditional statistical analyses.  There's even a spatial package, although you will better off sticking with open source GIS programs like GRASS or QGIS.  A good overview of its spatial package can be found here.

Want to examine social networks?  Then, Gephi's great!  I just analyzed my Facebook network in only a few minutes after following a tutorial.  In addition, Gephi has features and plugins to help you map geographic data
At some point you may also need Python.  Editing and organizing code, then give Notepad ++ a try.

A some point you will have to compress files, then 7-zip is a sure thing.  You may want to playback some videos or animations and VLC Player works great.

GIMP is a image maniupulation program similar to photoshop.  You can see an example of combining GIS with GIMP on a great GIS blog.

You will probably want to type up your results or make a few "PowerPoint" there's Open Office and the Libre Office implementation. If you need a standalone pdf creator, then there's PDF creator.

Lastly, if you ever want to venture away from Windows or other operating systems, there's Ubuntu--an easy installation of Linux.  Be sure the open-source or for-fee programs you want to run have a Linux version before making the switch.  Naturally, many open source programs have a Linux version but some do not.

Monday, July 16, 2012

Map Story: Organize Global Info Spatially

MapStory's website is a "compliment" to Wikipedia, according to the MapStory website.  Ultimately, its goal is "to enable any student, teacher or practitioner on Earth to tap the power of this new mode of conveying one’s stories, arrayed across geography and as they unfold over time. "  Sounds like a great open source GIS goal!

Let's take a closer look at how it is trying to achieve this noble goal. First, the site uses open source software called GeoNode.  Second, MapStory is well organized into discrete sections.  So, if you are only interested in certain topics you do not need to look at every map.  Thirdly, you need to get invited to publish your MapStory.  That's right, this is not a free for fall!  See the "How To" tab for the simple step(s).  Lastly, the site has a nice social feel, and you can search by Storyteller.

Note: MapStory although similar in name is different from ESRI's Story Maps site.

Friday, July 6, 2012

Spatial Analysis in QGIS

It is time to talk about spatial analysis.  Many open source GIS software have at least some analytic capability--more functionality is being added frequently.  Earlier, I showed a simple map of wifi locations in New York City using QGIS.  Let's take a look at the density or in this case area surrounding these points.  Since I have had trouble with kernel density, let's use Thiessen/Voronoi polygons.  Interestingly, these are only available with an ArcInfo license in ArcGIS, which is extremely expensive.  I am not going to compare results here, but let's see what the resulting map looks like.  The lighter/whiter the color the less area between wifi locations and the better the wifi availability.  (Of course I don't show whether the wifi locations are free or cost-based on this map).  Not bad for free data and free data analysis!  I used the nifty vector transparency plugin from QGIS so you can also see some of the land cover.

Click on the map and a larger version will appear.

Thursday, July 5, 2012

Power Outages in Washington, DC Area

 Visit Power Outages in Washington, DC Area.  Then scroll down and click the "View Both Images" Button.  A slider will appear on the photo that shows you the lights in the northeast before and after by moving your mouse.  The massive power outages were followed a rare "derecho" (straight in Spanish).  Basically, a line of thunderstorms, severe, winds, etc.  Be sure to check out the composite radar of this fast moving storms!

NASA Earth Observatory image by Rob Simmon using data from the NASA/NOAA satellite S-NPP. Caption by Aries Keck.
Instrument: Suomi NPP - VIIRS

Monday, July 2, 2012

Open Layers - Web Publishing

I found some free time, and I am beginning to work with Open Layers, an open source javascript library that anyone can use and edit to publish maps on the web. A lot of documentation is online but I also bought the beginner's guide, which can be purchased for $20 from the publishers website and downloaded as a PDF.  I definitely recommend reading this book!

For $60, I also bought a website domain and 10GB of hosting space for one year.  Right now, I am using sample code to experiment and to publish maps to the web.  You can check out an early example from sample code here:  A visitor can zoom in and out and change which Google Map base map is displayed by clicking a tab on the right and toggling a radio button.

 Google and other map providers allow you to use their basemaps for free, just be sure to follow the terms of service.  For Google, as long as your website is free and accessible to anyone, you are good to go.  Although there are limitations, for example on the size and resolution of their maps.

Tuesday, June 26, 2012

Quantum GIS v1.8 Released

This post is out-of-date. Please read:

Quantum GIS, commonly referred to as QGIS, has a new updated release: version 1.8 Lisboa.  Recent releases have been named after a different city.  QGIS is a bit more user friendly than GRASS.  Plus, it also has GRASS functionality along with other tools that GIS users frequently use, such as Python.

So, I put the newest version through a few quick tests.  The map below is of Wifi locations in New York City.  Via an Open Layers plugin, QGIS allows you to add layers for Google Earth, for example.  The WiFi locations were taken from Open Data NYC and symbolized with a custom marker by finding a .svg file of a wifi signal and placing it in the appropriate folder.  Next, I wanted to test the progress on a old buggy feature--kernel density. 

Unfortunately, based on attempts today and searching Issues in the forum, it appears any updates to the v.kernel did not make it into this release.  Why I am sad?  Well, kernel density is a basic part of exploratory spatial data analysis.  However, fortunately, many already existing spatial tools continue to work great and many general improvements have been made and are listed here.

Lastly, I checked out the attribute data for one wifi spot--turns out the coordinates are correct but the street is wrong (Centre not Center street)!  A 60 Center Street is northeast of 60 Centre Street.  So again, always be careful with open source data.  Clicking on the map below, will open a larger version.

Wednesday, June 20, 2012 -- Your Open Source Compass

Today, I want to talk a little about's website.  OSGeo stands for Open Source Geospatial Foundation--in other words the website is much more than just your average site!  It is more of a gateway to people, software, conferences, and other open source goodness.

The first thing you will see is a list of current open source GIS news, including updates on open source software releases, conferences, meetings and other tidbits of information.  To its right you will see a list of aggregated GIS blogs which is extremely helpful so you don't have to go hunt down each blog individually.

Somewhat hidden in the lower right hand side/corner is a list of of open source GIS software, both new and old.  If you are unfamiliar with the names, simply click a link a short description provides any user with a basic description of what the software does, the project's status/incubation, and what type of files it can use.  The page is also available in multiple languages in the opposite left hand corner.

Another cool feature is downloading a bundle of open source GIS software (OSGeo Live) without having to install it!  The download can be loaded onto a USB or DVD and lets you sample the software.  There's also a video of the best of open source GIS software.

Monday, June 11, 2012

Online GIS Webinars

Too busy to attend a talk or conference?  Stuck in the office or at home?  Fortunately, Directions Magazine Online brings GIS webinars to your desktop for free.  These webinars are about timely topics in GIS by solid speakers, many are well-known in GIS or its related fields.

Over the past several months, I have watched numerous webinars and have been impressed by the speakers and topics covered.  Most importantly, I have learned from them as well.  The "audience" for these webinars is also impressive.  The most recent one had ~ 500 viewers from across the globe.

One could argue that the webinars sometimes over-advertise or try to sell a service or degree program a bit too much.  However, I have found that a tasteful balance is achieved between GIS content and giving the speaker(s) a few minutes to talk about their company, product, or school.

The most recent webinar topic was remote sensing and sponsored by Penn State's Department of Geography.  Other topics in the near future include: Open Sensor Webs and the Open Geospatial Consortium (OGC), upcoming changes to ArcGIS Online and Online for Organizations, and geocoding.

Wednesday, June 6, 2012

Weather, GIS Viewers, and Data

With hurricanes, tornadoes, flooding, and hot weather upon us, weather and GIS are now as important as ever.  Fortunately, there are a number of online sources of open source meterological data and GIS viewers.  In addition, there are servers and databases that can be tapped into for continously updated of information.

NowCoast is a free real-time web mapping portal to information from the National Oceanic and Atmospheric Administration (NOAA).  The web mapping application is good and there are plenty of layers to choose from.  There are even WMS servers to tap into here:  The National Weather Service (NWS), whose parent agency is NOAA, also has a page separated by filetype: shapefiles, KML/KMZs, and web services. A screenshot of nowCOAST appears below.

It is also worth mentioning that the NWS is in the process of upgrading its website which you can check out here:

The Weather Underground's WunderMap, also free, provides a number of features and layers.

Intellicast also has an interactive weather map. Many weather websites also offer low cost subscription plans that upgrade the amount of features, data, and maps you can visualize.  Some sites are fee-based, but also provide free trials.

If you are more interested in climate and long-term trends be sure to check out the National Climate Data Centers (NCDC) Interactive Data Online Page.  Other resources are your local or state meterologist office, often affiliated with a university.

In addition, a number of very low cost and free mobile weather and radar apps are also available for Android and iOS devices.  Lastly, if you are not satisfied with your current weather website, check out this listing of 150 weather sites for North America.

Update #1: Be sure to check out this recent blog post on the NWS Enhanced data viewer:

Tuesday, May 29, 2012

Version Checks - May 2012

This post is obsolete.  For the most recent on version checks in 2015, please visit:

Keeping software up-to-date is extremely important. Open source GIS software is no exception.  Typically, updates bring fixes, stability (fewer crashes), sometimes security patches, and/or even new features.  Many people who use a computer or (mobile) device never really think about updating or upgrading the software--unless the software informs them of an update.  Still, a user may chose to ignore these messages and be unaware of the benefits. 

Updates for-fee/paid software are also important and sometimes may require you to update your license agreement depending on when you purchased the software, what version you own, and when the update was released.

On the other hand, a user may not know that an update has been released after the first installation.  IT folks may also rely on a GIS analyst to inform them of the latest updates.  Do not assume your IT person keeps track of all of the software and updates on your computer. Also, you may need their help if do not have installation privileges.  Some software is updated frequently, while others are updated annually.

So, after today's post be sure to have the latest (stable/released) version of the following! Keep in mind  they may be updated, so keep an eye on their website or subscribe to their e-mail listserves. These are the best ways to keep up-to-date.  Here's a quick list of a few open source GIS programs, their version numbers, and release date.

Grass GIS: Version 6.4.2 (Feb 2012)
Quantum GIS: Version 1.7.4 (2011)
Opticks Image Processing: Version 4.9 (May 2012)
GeoDa: Version 1.0.1 (Oct 2011)
Fusion LIDAR: Version 3.10 (May 2012)

Many open source GIS programs have a roadmap or 'wiki. These sources of timely information can give you the heads-up on when an update will be released and what features the new version may contain.  Lastly, they often contain lists of bugs and potential fixes.

Wednesday, April 25, 2012

Mobile GIS Apps

A number of GIS and related apps are worth checking out in the Apple App Store/iTunes or Google Play (formerly, Android Market). Many are free or low cost. 
  • ESRI has a free ArcGIS mobile app for iOS and Android that allows you to access maps created on  This app continues to have increased functionality and its future looks bright.  ESRI has a few other apps geared towards specific topics, i.e. business and health.
  • iGIS is an interesting app that I hope to use more.  Right now, it is free to download.
  • Geograph apps provides a relatively low cost way to view to geologic information for various states.
  • A Google Earth app with related imagery also exists
Presumably, when Windows 8 is released later this year, we should see GIS apps on that new platform. As some Windows tablets will be able to run regular Windows programs, running a full GIS like GRASS or QGIS off an inexpensive consumer tablet should be a certainty. 

Many other GIS-related apps, even if just data viewers, are popping up: from flood plain apps to earthquake information. There are also many GPS and navigation apps ranging from a few dollars to some of the most expensive apps you will find anywhere.

Lastly, both iOS and Android Development kits are free or low cost. ESRI and Google also offer ways to tap into their maps and map services (for free and fee-based) to bring geospatial information into an app that you create!

Wednesday, March 28, 2012

Natural Earth

Normally, I would not re-post information from another blog especially one written so recently.  However, this post was great (it is also a great open source GIS blog!)  The post describes the Natural Earth website: it provides free vector and raster data sets at several different scales for the entire Earth.  Generally speaking, there are three categories of data: cultural and physical vector data and raster data sets.

The data can be loaded into any GIS software.  Below, I have loaded raster data for elevation and a shaded relief into Quantum GIS (or QGIS), which I will talk about in later postings.  The layers are both pleasing to the eye and not excessively large in terms of file size.  Obviously, the larger the scale, the more detail, and the larger the files will be.

Clicking on the image above will bring up a larger view in a new window.

Monday, March 19, 2012

Open Government

Transparency is an important part of governance.  More data than ever before is being put online including geospatial information.  Many local governments now publish data online through Socrata.  Examples of local governments using their interface include New York City, with nearly 1,000 datasets, and Chicago. Many smaller local governments are using it as well. Geographic data in shapefiles and spreadsheets with attribute data and latitude and longitude coordinates can be found amongst the files.  Apps can also tap into Socrata through an open source API called SODA.

However, what data is published openly should be carefully weighed against privacy, safety, and security concerns.  In many cases, the publishing of such data will be clearcut as the data may already be published elsewhere.  However, grey areas will always exist.  Data published or intended for one audience may also be of use to others with more nefarious plans.  Having large amounts of data organized in one place naturally eliminates barriers to access but also makes to use for people that intend to do harm--potentially making their job easier.

Satellite imagery, especially if refreshed frequently, can be especially sensitive.  Terrorist groups have long been known to use open sources of geographic information and applications such as Google Earth to facilitiate attacks. 

Some solutions are obvious but given the diverse security threat, the risks of open publishing may not always be readily apparent.

Friday, March 16, 2012

Open Source Image Analysis Software

One area of open source GIS that needs more software is remote sensing, imagery, and its analysis and interpretation. There is an endless amount of environmetal data from remote sensing, which is free to access, but few free programs to view and analyze them.  I will briefly discuss two software programs here, and I will post additional information on them in the coming weeks.

The first is Opticks which is a great program!  It comes with the ability to add extensions for greater functionality from its community of develpers and users.   Specifically, the extensions help perform basic and complex tasks that expedite using satellite imagery.  It also comes with the ability to run Python scripts and a wizard builder (akin to Model Builder in ArcGIS).  More and continuous updates are planned for Opticks in the near future! 

The next is MultiSpec which is a lightweight program, in terms of size, but also has great functionality.  A new version was just released in late February.

In my coming posts, I will talk more about these exciting open-source software and what they can do!

Monday, March 12, 2012

Viva Landsat over Las Vegas

The Landsat mission tracks changes in land cover over Las Vegas in the video below.  The compilation was released about one week ago but is still fun to look at.  The Landsat mission may receive an extra boost, already well exceeding its lifetime, if the Landsat 5 satellite comes back online.  The next Landsat mission is expected to begin sometime in 2013.

Wednesday, March 7, 2012

Open Source LIDAR Software

I had never seen or heard of an open-source program for viewing LIDAR data, which is increasingly in use.  I do not use LIDAR in my daily work, so it seemed like an interesting challenge. I hoped to find something simple to be able to load an occasional LIDAR data set for exploring.

There are several extensions and add-ons out there.  After searching, I found FUSION software by the Pacific Northwest Research Station / Forest Service. It is stand-alone software.  A new version was just released in early February 2012.  Recent and continual updates for any open-source software are always encouraging to see and to maintain its relevance. The website includes sample data (for Washington State below) and a well-written manual.

The screenshots show the wide range of graphics that FUSION can produce.  After importing an aerial image/DOQ and the LIDAR data, you select an area of interest, and a new window automatically opens.  One can perform a variety of tasks simply by right-clicking--including generating a canopy surface model and even producing anaglyphs for 3D.  There is even the very appropriately named "Wiggle-Vison."

Sunday, March 4, 2012

The Road to Somewhere...

Open geographic data sources are great, but there are pitfalls...Take roads, for example.  Many GIS files for roads are created for different reasons and different periods of time.  Precision roads for navigation can be pricey.  The choice of road files can have a direct impact on the project you are working on.  The below shows roads from the U.S. Census Bureau (red) compared against the center line file from an open city data warehouse (black). The census data actually have a line/road going through the sports stadium.  In some places, red lines appear where there are no black lines and vice versa.

Wednesday, February 29, 2012

Open Access Health GIS Journals

My background is in public health and GIS, so one of my favorite open access GIS journals is the International Journal of Health Geographics.  The breadth of topics and analysis covered is impressive and it is a good place to start when conducting a literature search. In addition, the Public Library of Science Journals (PLoS) frequently contain spatial analysis.

One problem with health and GIS is performing literatures searches. Since geographers and public health professionals use many terms to describe GIS, it can be very difficult to search for and identify relevent articles.  For example, a search of PubMed finds only 1,200 articles for 'health and GIS' but almost 8,000 for 'health and geography.'  So, watch what terms you use to search!

Besides health, there are an extensive list of GIS journals, some pay-per-access and others open access. Although published only a few times per year, I came across the URISA journal which is an interesting read for anyone involved in GIS in government.  The Journal of Geographic Information System has an international scope.

Lastly, as I have considered writing, I have found some 'open source' journals charge to have an article published while others absorb the cost.  Fyi, and something to keep an eye on when you start to write.

Tuesday, February 28, 2012


GRASS GIS is one of the oldest open source software out there, and has extensive capabilities for GIS.  It was my initial encounter with an open source GIS.  While many parts of GRASS will feel familiar, adopting to folders, workspaces, mapfiles, naming conventions, and ensuring projections are correct will help you get acclimated a lot faster.  Be sure to understand all of these and where they are located on your computer before you begin.  Other open source GIS desktop software have adopted similar convetions, so learning in GRASS will be a good investment.

Moreover, GRASS has extensive 3D capabilities --an increasingly important part of GIS. If all maps are representations of reality, then putting them into 3D certaintly goes a long way towards feeling more real.  I am not a 3D analyst, so for me GRASS is a great learning tool that also carries over occasionally to work.

Open Source GIS

Open source desktop software for Geographic Information Systems (GIS) have impressed me over the last six months.  Therefore, I have begun to expand into other open source areas, namely image processing with Opticks and, time allowing, open source web publishing tools in the months to come. At first I struggled with some of the software packages, but the hard work is beginning to pay off. My hope is to share some of the benefits, negatives, and advanced applications available to users of open source GIS.

For those looking to start using open source GIS, is the place to start:

In my next few posts, I will describe some of the major open source GIS software starting with GRASS GIS, Quantum (QGIS), and Opticks remote sensing and image processing software.  In addition, I will talk about free sources of geospatial data.