MapDawg is a free internet site that provides numerous links to both international and domestic spatial data. Depending on where you are interested in studying it can often be difficult to find sources of reliable data. This site provides links to both governmental and private sources of spatial data that are generally ready to use with your GIS. The website alphabetically organizes the data by place starting with worldwide and international locations. Data are given from multiple continents, countries, and from all of the states within the U.S. The data found on these websites are compatible with Cartographica so …

Google has released an interactive map tracking the results of yesterday's Iowa Caucus. The map provides interesting information about the results for each county within Iowa. The map highlights the results for each candidate that participated in the highly publicized vote that kicks off the run-up to Republican Presidential nomination. According to the results, Mitt Romney and Rick Santorum gained the highest percentage of votes at 25% each. The two candidates were only separated by 8 votes (Romney was the winner). Ron Paul also had a good showing gaining 21% of the vote, however he gained zero delegate votes. Click …

This week, we launched out new support site, using Zendesk. Besides a smoother ticketing system, we are also happy to announce that we have taken the feature request, help and tips areas and made them much more accessible. Please join us in inaugurating this new site by visiting, asking your questions, adding your feature requests, and voting on your favorite requests and topics.

One of our participants from Australia has kindly sent us information about a number of resources available for mapping there. If you know of some good publicly available (or very good paid content), please feel free to Contribute a short article using the Contribute button at the top of the page and we'll approve it into the system. Without further ado... In no particular order: Western Australia Land Information Authority Australian Government Geoscience Australia MapConnect (250K Topographic Data for download) AU Government | Bioregions Data Queensland Government Information Service Geosciences Australia IBRA (Interim Biogeographic Regionalisation of Australia) Department of Environment and …

Many of us spend a lot of time looking for data to use for maps and I wanted to mention Natural Earth, a site whose tag line "Free vector and raster map data at 1:10m, 1:50m, and 1:110m scales" pretty much says it all. There's a lot of stuff here, and it's good for many purposes, and it's truly free, as in Public Domain. The data can be dragged and dropped directly into Cartographica for use in your own projects, without any licensing issues, which is fantastic.Further, there are both raster and vector data sets, so …

Occasionally it is necessary to summarize the data from a layer of points based on containment within a polygon layer. This article presents a relatively straightforward way to do this with Cartographica. The solution to this problem requires the use of both an internal command and a small AppleScript, which we will provide. This simple script can be modified for your individual needs to apply basically any formula, but in the example case, it provides the sum of the values of a single column in the point dataset. At the end of this piece, we'll discuss some easy adaptations of …

Yesterday we learned of the death of a man who had a profound effect on the course of my life and the life of this company. I am sure that this sentiment has and will be reflected many times, but it makes it no less true in our case. Our thoughts and prayers go out to his family and all of those whose lives were touched by him. I never knew the man personally, although I stood in the same room with him many times. I have owned at least one Macintosh since 1984 (including a dark period where I …

ClueTrust is pleased to announce the immediate availability of CartoMobile® 1.1 on the App Store! New features include adding lines and polygons, easy use of Raster data as base maps, multiple projection support, and more! Version 1.1 of CartoMobile is a huge release for us, starting with the name change. ClueTrust has decided to re-brand Cartographica Mobile as CartoMobile, both because the name "Cartographica Mobile" just doesn't fit well in the app screen on the iPhone, and also to differentiate its place as a field data tool, as opposed to a full-fledged GIS, like Cartographica. CartoMobile 1.1 …

ClueTrust is happy to announce the immediate availability of Cartographica 1.2.4, a bug fix release for Cartographica 1.2. This release contains no new features, and fixes a handful of bugs (some peculiar to OS X 10.7 Lion). The full release notes are available at MacGIS.com.

I recently found a website for Nordpil who have made available a data set of major urban centers world wide. The data set contains population data for all of the world's major cities. I created a Kernel Density Map using Cartographica to show where the highest densities of urban areas are located. I discuss the process in this post. Cartographica makes it easy to quickly explore GIS data. If you need the data for professional purposes then Cartographica allows you to make sharp looking maps in only a matter of minutes, while also allowing you to visualize your data. I …

ClueTrust is happy to announce availability of Cartographica 1.2.3, with updates for Lion compatibility and a handful of new features, as well as performance improvements and bug fixes. Check out the improvements in WFS, projection handling, import/export, performance for AppleScript and labeling. Come check it out at MacGIS.com. We are also providing a new 7-day key for anyone who has previously evaluated the software by visiting the lost key page. The feature list for this maintenance release is short: Support for exporting data tables from layers Automatic export for CartoMobile imagery Support for exporting raster layers …

In a recent article by Time a state lawmaker from California has suggested that California split into two separate states. While the article mentions that this is not the first time this type of shake up in the state has been suggested (Its been suggested 220 times!) the proposal seems to be getting more coverage this time around. I found the idea of splitting interesting and I wondered how the two states would differ in terms of social and political issues. For this post I am going to see which of the two new states would have more economic problems …

Rates are useful when we need to compare geographic units that have unequal distributions of population. For example, if we wanted to compare car ownership for two California counties, say, Los Angeles County and Fresno County we would want to take into account the populations of each county. If we did not take into account the population then we might conclude that people in Los Angeles are more likely to own cars than people in Fresno. However, it is possible that this is not the case. It may be that the density of car ownership is much higher in Fresno …

Cartographica is great for exploring data and for providing a quick way to evaluate geopolitical problems. The South China Sea dispute is an ongoing feud between the countries that have land bordering the South China Sea. In this post I show how to quickly add data and to create new layers that can be used to evaluate problems. This post is fairly practical. I read an article about the South China Sea dispute and found the issue to be quite interesting. However, I know little about the area and thought that a little analysis of my own might help me …

ColorBrewer is a free online database of color palettes that are designed to be used with GIS. The website allows users to select from a variety of colors that have been pre-selected and formatted for both quantitative and qualitative data. In this post I will show you the steps for quickly bringing ColorBrewer color schemes into Cartographica. Cartographica can accept palettes directly from the ColorBrewer site for use in the Color Palettes Window. Although we specifically point at ColorBrewer for good palettes, Cartographica can import any combination of numbers where the Red,Green, and Blue components are separated by commas …

Arizona is currently experiencing a large wildfire on its Eastern border. The fire has been raging for several weeks and new satellite imagery produced by the U.S.Department of Agriculture Forest Service allows us to keep a daily watch on the fires. A great thing about the USDAFS data is that it is downloadable in Geotif format which allows for easy mapping and exploration. In order to get the data into Cartographica all you need to do is download the GeoTIFF and then import the data as a raster file. Below are several of the images. The images are …

The Housing Price Index is a quarterly report produced by the Federal Housing Finance Agency that describes the quarterly performance of home values. The index is an important measure of the economy especially because of the recent problems in the housing sector. For this post I created a state level data set showing the percent changes in the HPI across the United States since the last quarter of 2011 using data from the FHFA In the image below the states that are in red have experienced the most problems with decreasing home values. States with either light or dark blue …

Cartographica makes retrieving and displaying Web Map Service data very simple. Cartographica comes out of the box with several WMS links already incorporated into the program. However, the list of available WMS data available online is much broader than what is included as a link with the program. In this post I will show you how to find additional WMS data and then how to add and display the data using Cartographica. The methods for finding WMS data is as much an art as a science. The most effective method for finding WMS data is doing a Google search to …

On April 27th 2011 Tuscaloosa, Alabama was hit with an EF-4 tornado that had winds at nearly 200mph. According to the National Weather Service the tornado was at least a mile wide and stretched nearly 80 miles in length. Tornado warnings were in effect between 3:40 and 8:00pm. The number of fatalities within the city of Tuscaloosa was staggering as it was last reported as 41 the Tuscaloosa News In order to highlight the path of devastation of the tornado I obtained a satellite image from Public Intellegence The image shows the path of the tornado, which I …

The Modifiable Areal Unit Problem (MAUP) is an important issue for those who conduct spatial analysis using units of analysis at aggregations higher than incident level. The basic issue with the MAUP is that aggregate units of analysis are often arbitrarily produced by whom ever is in charge of creating the aggregate units. A classic example of this problem is known as Gerrymandering. Gerrymandering involves shaping and re-shaping voting districts based on the political affiliations of the resident citizenry. The problem was first described by Openshaw (1984) when he stated "the areal units (zonal objects) used in many geographical studies …