PCB Fact Sheet

Blog #2

Choropleth Map

This type of map is valuable because it gives a visual representation of a measurement and its variability across a geographic region. For example this map give a visual representation of acres of land harvested for hay and grass and the variability in the density of acres harvested. These types of maps are excellent in representing the distribution and severity of the variable you are targeting. If this showed the distribution of type 2 diabetes cases for example it could aid public health professionals in targeting at risk communities where the cases are most densely present. It will often show this variability in color shading across different regions.

Isarythmic Map

This type of map is valuable because it shows continuous variables such as precipitation or temperature in a smooth visual representation. This shows the flow of these different variables across the target landscape which can help in seeing large changes in patterns. If a emergency preparedness professional wanted to know the flooding risk in an area they might use this type of map to help justify focusing resources on specific regions.

Dot Density Map

This type of map is valuable because it helps show the locations of a target variable. It can show where the target variable is most densely present. A person might use this map and look for associations between these locations and lung cancer, or these locations and the frequency of diseases caused by exposure to toxic pesticides. 

Proportional Symbol Map

 This type of map is valuable because it shows the relative proportion of a variable across a geographic area. For example this map shows coal consumption and the size of the circles are directly proportionate to the level of consumption in each location across the targeted geographic landscape. This shows public health and environmental health professionals where consumption is the greatest, which can give them target locations to measure the negative impact of the coal industry on health outcomes. This could also aid environmental health scientists to justify stricter legislature for particulate matter and ozone in these areas to improve health outcomes.

Environmental Sensitivity Index Map

The value of an environmental sensitivity index map is that it provides information regarding the location of human and biological resources. It also provides a visual representation of the shoreline sensitivity and the resources that could be at risk during an environmental accident. These types of maps are valuable tool for emergency responders during an oil spill for example. The map could aid in the planning phase prior to the occurrence of a natural or man-made disaster to outline cleanup strategies and prioritize areas of focus.