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Wednesday
Sep052012

Mapping 7.6 Earthquake in Costa Rica

There was a large (7.6) earthquake yesterday in Costa Rica. The earthquake signaled tsunami warnings in the region, but fortunately there was no tsunami. So far there have been three deaths reported. In the past 40 years Costa Rica has experienced more than 30 earthquakes of 6.0 magnitude or higher. So, needless to say Costa Ricans are accustomed to these types of events.

The purpose of this post is two-fold. The first purpose is to draw people's attention to the major geologic event that occurred in Costa Rica yesterday. The second purpose is to show a couple quick methods for creating concentric rings, which we have had questions about from some of our customers in the past. Concentric rings are used in a variety of ways, but one way you often see them used is in reporting the location of earthquakes.

Start by Adding a Live Map by choosing File > Add Live Map. After you add a live map choose Layer > Include in Map Extent. Including the Live Map layer in the map extent is necessary because it will enable the zoom functions to operate beyond the extent of the point layer that you are about to create in the following steps.

According to reports the earthquake occurred just off the cost of Costa Rica. To add a point representing the location of the earthquake choose Layer > New Layer and then choose Edit > Add Feature. A window will appear allowing you to choose the type of feature you would like to create. Select Point and then place the point by holding down the option key and clicking on the location about 50 miles off the coast. See below for an example.

There are two options for creating concentric rings. The first method involves using the buffer tool to create rings around a point at specific distances. To create a buffer choose Tools > Create Buffers for Layer's Features. A window will appear that will allow you to set the parameters of the buffer. Set the Uniform Width distance to 25 Miles. See below for an example.

To create new buffers at different distances select the Earthquake point layer in the Layer Stack, and then repeat the steps above to create buffers around the Earthquake point at 10, 50, and 75 miles. (Note: Be sure after each buffer is completed that you re-select the Earthquake point layer before creating the next buffer). When completed you will have four layers that are represented on the map by white circles. Double-click on the top buffer layer in the layer stack, click on the Fill box and then change the layer opacity to zero. Next click on the stroke box and change the color to red. See below for an example.

 To make all of the buffer layers have the same layer styles drag the top layer in the layer stack (the one you have already changed) on top of the other buffer layers. This will automatically match the layer styles. See below for a final image of the concentric rings created by using buffers.

The other method for creating concentric rings is to use an image from the internet. This method is not as precise as the buffer method because you cannot designate the distances for each ring. However, it is a quick alternative method for creating concentric rings. The first step is performing an image search for "concentric rings" using Google or a similar search engine. Find a clean looking example of concentric rings. Double-click on the earthquake layer in the layer stack and then click and drag your concentric ring image to the symbol box in the Layer Styles Window. Finally, change the stroke color to red and increase the point to a desired size . See below for an example of the Layer Styles window.

 Uncheck the four buffer layers that you created previously to reveal to new concentric rings that were created with an image from the internet. See below for an example of the final map.

Wednesday
Aug292012

Mapping West Nile Virus in the United States

West Nile has increasingly become a concern of U.S. health professionals and officials at the Center for Disease Control and Prevention. A recent interview reported in USA Today revealed the concern that the CDC is giving the recent West Nile outbreak. According to the article, CDC Director of Vector-Borne Infectious Disease, Lyle Petersen, is quoted as stating, "We think the numbers may come close to or even exceed the total number of cases reported in 2002 and 2003, both of which were severe West Nile virus years." According to CDC numbers there were more than 250 deaths due to West Nile in 2003. Obviously, the concern of the CDC official is understandable. 

In order to provide a little more context to this situation I have created a dataset that is available for download. Click on this link to download the West_Nile.csv data. The dataset was created based on numbers provided by this CDC Webpage. The dataset provides the current number of positive tests for the West Nile virus. The link to the CDC webpage in the previous sentence also provides a county level map showing the specific counties where West Nile has been confirmed. Unfortunately, the county level data are not available for download.

In order to create a state level map you will need a map of the US to import into Cartographica. Download a map of the lower 48 states here

To create the West Nile map begin by importing the data.

Choose File > Import Vector Data and choose Lower48.shp

Next, you need to join the West_Nile.csv file to the Lower48.shp file. 

Choose File > Import Table Data  and choose West_Nile.csv  This will bring up the Import File Window. 

Click the Join tab in the top right, change the Target Layer selection to Lower 48, and then match the two files together by changing the Map to selection in the State_2 field to State, click on the check box, and then click Import. Below is an image of the set up. 

Bring up the Layer Styles window by double-clicking on the Lower48 layer in the layer stack. Create a chloropleth map by adding 6 categories to the table by clicking on the + button 6 times. Distribute the West Nile Incidents by changing the Based on selection to West Nile Incidents and then clicking on the Gear Box and selecting distribute with Natural Breaks (Jenks). You can assign a color scheme by choosing Window > Show Color Palettes and then clicking and dragging a color scheme to the table within the Layer Styles window. Below is an image of the set up.

Below is an image of the final map for the West Nile Incidents in US states below. 

 

Tuesday
Aug212012

Mapping Wildfires in Russia and Asia

Drought conditions and high temperatures throughout the world are causing problems with wildfires. There are presently several thousand wildfires burning throughout the world, which have resulted in millions of dollars worth of damage. NASA has made available a set of shapefiles that identify the locations of wildfires presently burning throughout the world. The shapefiles are nearly real-time with data available at time intervals of 24 hours, 48 hours, and 7 days. Click on the following link to Download the wildfire data

For this post I downloaded the wildfire data from Russia and Asia. Once the data are downloaded import them into Cartographica by choosing File > Import Vector Data. I provide an image below of the map of Russian and Asian wild fires. 

To enhance the fire map you can change the point symbols from circles to an actual fire symbol. To do this go to Google and perform an image search for "Fire". You will be able to find an image that can be dragged to the Layer Styles window. To open the Layer Styles window double click on the Russia and Asia fire layer in the Layer Stack. Then drag the fire image to the symbol box within the Layer Styles window. Once the image is added uncheck the stroke box. See my images below. 

Below is an image with the fire symbols.

A final map shown below was created using the Kernel Density function. To create a Kernel Density map choose Tools > (while holding down the option button) Make Kernel Density Map. Choose the Exponential (Negative) function and click Analyze. I provide an image of the Kernel Density window below.

My final map shown below is of the Kernel Density of wild fires in Russia and Asia. To change the color scheme choose Window > Show Color Palettes. Select the color scheme you would like to use and then click and drag it to the KDM layer in the Layer Stack. The color scheme I selected is a custom color scheme called Fire Ramp. 

Wednesday
Aug012012

Mapping the Olympic Medal Counts

We are continuing our coverage of the 2012 Olympic games in London, England, and we have an updated medalcount.csv file that can be used to map the distribution of medal counts around the globe. Download the medalcount.csv file. The medal counts are accurate up to 1:00pm on Wednesday, August 1. [Updated Final medal counts are available by downloading Final_Medal_count.csv]  Once downloaded, save the file as a .csv. This dataset can be used to create chloropleth maps and can be continually updated as the games progress. 

Download the World file from Geocommons  and then import the data by choosing File > Import Vector Data. View the previous Cartographica blog post, "Mapping the Distribution of Olympic Athletes" to see the problem with joining data Hong Kong data to the geocommons file. Essentially, Hong Kong is included inside of China on the Geocommons file rather than being an independent nation, in the post linked above I show you a way around this problem.

Join the medalcount.csv dataset to the World shapefile by choosing File > Import Table Data. This will bring up the Import File Window. Click on the Join tab in the top right pane, change the Target Layer to World, in the left pane, change the Map to option in the FIPS field to FIPS_CNTRY, and check the Key box. When ready click Import. The final dataset will then include the original data from the World file from geocommons and it will also include the data imported from the medalcount.csv dataset. As a result, there will be two country name columns (one from both files), the FIPS_CNTRTY column (from geocommons), and the Number of Athletes column and the Gold, Silver, Bronze, and Total Medal Count columns. (from the medalcount.csv file). There are two country name columns in the final dataset because the geocommons and medalcounts.csv files each included a "country name" column that was not used in the joining procedure. The FIPS column from the medalcount.csv dataset is not imported because the FIPS column is used to match to the FIPS_CNTRY column from the geocommons World file. Since the medalcount.csv data are imported based on the identical match between the FIPS column and the FIPS_CNTRY column, it follows that if the FIPS column was imported it would be an identical match to the data in the FIPS_CNTRY column. See below for the set up. 

You can create a chloropleth map of the distribution of the medal counts by double-clicking on the World layer in the Layer Stack. Change the Based on menu to Gold, Click on the + button five times to add five categories, and then click on the Gear box and select Distribute with Natural Breaks (Jenks). To add a color scheme choose Window > Show Color Palettes and then click and drag a color scheme into the table within the Layer Styles Window. For this post I used a customized color scheme. To learn how to create your own customized color schemes see the our previous blog posts titled "Introducing 1.2: Color Palette Management". Also, see another of our blog posts titled "Using Color Brewer with Cartographica" for additional help in creating custom color schemes. I provide an image below of the Layer Styles Window below. See below for my maps. 

Wednesday
Jul252012

Mapping the Distribution of Olympic Athletes

The 2012 summer Olympics in London, England are here, which is very exciting for many athletes and fans of sports from across the globe. This year's Olympics will host athletes from more than 200 countries and will consist of nearly 40 sports. The games will run from July 25 - August 12; for a schedule of the events take a look at the schedule on the official Olympics website. To celebrate the diversity of the event we decided to build a dataset that contains the countries participating in the Olympics along with the number of athletes from each location.

The first step in mapping the distribution of olympic athletes is collecting a shapefile that contains all of the world's countries. To download a World shapefile go to this Geocommons webpage and click on the shapefile download button on the right side of the page. The file should only take a few seconds to download. Once downloaded save the file to your desktop.

To import the downloaded World shapefile choose File > Import Vector data. One problem with the World shapefile is that Hong Kong is included within China. In the 2012 Olympics Hong Kong is independently represented by more than 40 athletes. This problem is easily fixed by using the Add Feature tool in Cartographica. Zoom in to the area of China that contains Hong Kong. If you unfamiliar with where exactly Hong Kong is located use the Live Map Feature to locate Hong Kong. To add a live map choose File Add > Live Map (select Bing Maps with Roads and Aerial Imagery). Locate Hong Kong (its in Southern China, along the coast), and then zoom in. See my image below of Hong Kong.

To add Hong Kong to the World shapefile select the World shapefile in the Layer Stack and then choose Edit > Add Feature. Cartographica will enter Edit mode and will allow you to draw in the boundary for Hong Kong. To draw in the boundary hold down the option key and click to place control points. First Draw the boundary around the largest (non-island) area. After the points are placed hit the return key. See my image below for an example.

Because there are two islands included in Hong Kong we need to create two new features for each island with the ultimate goal of merging the three new features into a single feature. Using the same methods as above add the two new features. Notice in the data viewer there are now three new features. See the image of the data viewer below.

To merge the three features select each one as shown above in the data viewer, and then choose Edit > Merge Selected Features. The three features should collapse into a single feature in the data viewer, and when selected the two islands should be included in the new Hong Kong feature. To complete the addition of the new Hong Kong feature you can manually add the appropriate data into the data viewer. See my image below for the added data.

To continue to follow along with the blog, Download the Olympic Athlete dataset. After it is downloaded save the file as a .csv file. Join the Olympics dataset to the World shapefile by choosing File > Import Table Data. This will bring up the Import File Window. Click on the Join tab in the top right pane, change the Target Layer to World, in the left pane, change the Map to option in the FIPS field to FIPS_CNTRY, and check the Key box. When ready click Import. The final dataset will then include the original data from the World file from geocommons and it will also include the data imported from the Olympic dataset. As a result, there will be two country name columns (one from both files), the FIPS_CNTRTY column (from geocommons), and the Number of Athletes column (from the Olympic file). There are two country name columns in the final dataset because the geocommons and Olympic files each included a "country name" column that was not used in the joining procedure. The FIPS column from the Olympic dataset is not imported because the FIPS column is used to match to the FIPS_CNTRY column from the geocommons World file. Since the Olympic data are imported based on the identical match between the FIPS column and the FIPS_CNTRY column, it follows that if the FIPS column was imported it would be an identical match to the data in the FIPS_CNTRY column.

You can create a chloropleth map of the distribution of Olympic athletes by double-clicking on the World layer in the Layer Stack. Change the Based on menu to Number of Athletes, Click on the + button five times to add five categories, and then click on the Gear box and select Distribute with Natural Breaks (Jenks). To add a color scheme choose Window > Show Color Palettes and then click and drag a color scheme into the table within the Layer Styles Window. I provide an image below of the Layer Styles Window.

The next image shows the distribution of athletes from across the globe. To add the Legened in the bottom choose Window > Show Legend.