The ninth lab of our Cartographic Skills course introduced us to another variety of thematic mapping. Isarithmic maps may be most familiar for depicting elevation and weather-related phenomena (rainfall, pressure, etc.). However, isarithmic maps can be used to represent any data that are continuous. As seen in the above two maps, data represented in isarithmic maps can be symbolized in different ways. The top map depicts the precipitation data of Washington State in a continuous tone while the lower shows a hypsometric tint symbology. It is simplest to think of the data in the latter category of map as being classed while the former is unclassed. Continuous tone maps do a good job of accurately representing the data (as interpolated from control points), but it can be difficult to interpret the data value for specific locations. The hypsometric tint map may be easier to interpret, but the classed data, as in other types of classed data maps, may skew one's interpretation of the data.
My primary creative contributions to these maps involved experimenting with different gradient patterns for the background. I also increased the width of the legend for the continuous tone map to make the color ramp easier to interpret. Although the high-to-low value orientation of this legend was accidental at first, I decided to leave it this way since the majority of the low values are in the eastern portion of the state and the high values are in the west. This decision may cost me a point or two, but it made sense at the time. I also experimented with different symbologies and labeling styles for the elevation contours on the hypsometric tint map. However, I could never settle on a symbology that was not cluttered and difficult to read, thus I decided to keep the contours simple and unlabeled.
No comments:
Post a Comment