Lab 9

This lab was all about isarithmic mapping. Isarithmic mapping is mostly known in its for as a contour map. It is mainly used when the data set shows a smooth transition between phenomena. This lab we mapped the average annual rainfall for Washington state over the past 30 years, from 1980-2010. We used two different types of maps, the continuous-tone and the hypsometric tint. The continuous tone map uses a gradient color scale to show the change from low to high concentration. The hypsometric tint map, on the other hand, uses a stepping scale much like a chloropleth map. Also the hypsometric tint map uses data classification to break up the phenomena into classes. I prefered this map because I felt that it was easier to see the distinct changes between concentrations. Overall, I liked this lab because the instructions were very laid out and easy to follow. The one thing that I did not like is how ArcMap has the contour lines set up. You have to manually insert the data points at which you want your contours to appear. I feel that with the automation that ArcMap has built into it there should be an option to allow it to figure out the best points for your contours.