Video: Open GIS Data Portals

Open GIS data portals are becoming more common, and can contain lots of geospatial data, but is it a case of too much of a good thing?

What is a Portal?
An internet site providing access or links to other sites. In the case of open GIS data, the file may appear on the same page, link out to another website (or portal) or require more digging.  In addition, some GIS portals have links to web map services.

Search is the thing...
Open data portals house more and more data and therefore can become more difficult to search over time. Creating complex searches is sometimes not available and can slow the discovery process.

What are they made of?
Open data portals leverage free and open, propriety, or hybrid data and/or GIS platforms.

Here one minute, gone the next...
While often data can be downloaded directly, some sites link to external or partner data sources. Some data may seem accessible and near-at-hand but actually require more searching and digging.

Syndication
In some cases, this is the result of syndicated data sets. For example, on federal data portals, local and state governments can have their data sets metadata appear in search results and link out to the resource.  In others, this can be overused, frustrating, or lead to broken links or missing resources. Sometimes going directly to the source can be easier than navigating a much larger data portal.

Examples
We will look at several open data portals for geospatial data:

• Data.gov
• ESRI's Open Data
• National Weather Service GIS Data Portal
• NYC Open Data

Also check out http://dataportals.org/ for a neat interactive map of open data portals worldwide.

Looking for an open data portal?  Check out the interactive and searchable map on dataportals.org

Video: QGIS Print Composer - Side-by-Side Maps and Atlas

QGIS has a powerful print composer that allows users to create complex maps very quickly.  Two common practical examples include creating: 1) side-by-side (or multiple maps) on the same canvas/layout and 2) a map book or atlas. This week's video looks at these cases: https://www.youtube.com/watch?v=gCISvTfHtZc.

In the video, we will create side-by-side maps of different band combinations of remote sensing imagery of the Salton Sea.  For a related blog post, visit:
http://opensourcegisblog.blogspot.com/2015/08/tutorial-side-by-side-maps-in-qgis.html

We will also use the atlas to take a closer look a battleground states during the 2012 presidential election.

Lastly, I searched high and low, but I could not find any guidance or cartographic reference on creating side-by-side maps. So, I looked through several dozen examples, found a couple of themes, and drafted some suggestions --which you can find towards the introduction--and below.

A few suggestions for creating multiple maps on the same canvas/layout.

In the coming months, we will also re-visit the atlas function in print composer and look at more complex examples.

Video: Tips for Using QGIS Print Composer

QGIS Print Composer can be a little awkward to use at first.  It is analogous to Layout View in ArcGIS.  We will look at some tips to make it easier to use and understand how to create maps in QGIS.

In the video, we will review a map of 2012 Presidential Election Results, as seen below.

In Part II, I will show you how to create side-by-side map series, which is great to look at changes over time as well as different band combinations in remote sensing.  We will also take a look at creating an atlas or map book, essentially iterating/repeating the map making process by a geographic area.  Lastly, we will take a look at the QGIS Map Showcase on Flickr.

If there is something you would like to see, let me know in the comments section below.

Update #1: Print composer has an add Legend button but in this video I used an image file because I used some fancy rule-based symbology, the legend was not easy to look at. Normally, I would just select add Legend.

Video: Free and Open Source GIS Reference Data

After last week's post looking at the landscape of free and open source GIS software, the next logical step is looking at open GIS data. This video looks at reference data. I am still deciding on what to do the next video on...the choices are a) Open data portals, b) novel data types, social media (TwitteR and Instagram), or c) remote sensing.  Let me know what you would like to see in the comments below.

Topics covered in the video include:
Census: https://www.census.gov/geo/maps-data/data/tiger.html
DataFerrett: http://dataferrett.census.gov/
Summary File 1 DVD: https://www.census.gov/mp/www/cat/decennial_census_2010/summary_file_1_1.html
Natural Earth: http://www.naturalearthdata.com/
OpenStreetMap: https://www.openstreetmap.org/
GeoNames: http://www.geonames.org/
US Board on Geographic Names:http://geonames.usgs.gov/domestic/index.html
Maryland Department of Planning/ACS: http://www.mdp.state.md.us/msdc/S7_ACS.shtml

Video: A Quick Introduction to Free and Open Source GIS

My first video has been posted to YouTube.  It briefly covers the landscape of free and open source GIS (FOSS GIS), remote sensing and processing, a few related tools, and JavaScript libraries for creating online interactive webmaps.  It does not cover every program out there but gives new and returning users a place to see all of the options available.  You can check it out here: https://www.youtube.com/watch?v=rB_qnTE-W9c or subscribe to the channel by clicking here.

I hope to bring out more videos in the near future including delving into each of the programs and step-by-step tutorials.  So stay tuned!  As always feel free to leave comments, questions, or feedback below.  Be sure to like the video and subscribe if you would like to see more.