What does this map reveal?

Compare the African-American mortality rate intensity (top) with the white mortality rate intensity (bottom) in the right screenshot. For this example, the “White Mortality Range Value” for “0.3” has been altered to “3.6” to reflect the upper-half of the white mortality range. This narrows the visualization down to show only those counties where white mortality rates were highest.

While African Americans obviously suffered disproportionately higher mortality rates in north Florida, some of the highest white mortality rates were clustered there as well. The utility of a heat map is its ability to reveal the proximity and concentration of phenomenon. This map shows that around Pensacola and in those cities in the triangle between Tallahassee, Gainesville, and Jacksonville, clustered together, produced the most intense white mortality rates in the state.

For whites, those cities and counties may not have produced high mortality rates on their own compared to cities like Tampa in Hillsborough County or Jacksonville in Duval County, but when clustered together the map reveals how intense the mortality rates were when viewed proximal to one another. There appears to be a higher concentration of mortality in that triangle than in counties with large population centers. We don’t know why flu mortality was so high in that triangle.