Transparent colours? No justification is necessary.
The following script will produce a random scatter plot, in the style of Figure 1. The fourth component of the “rgb” function indicates the transparency. I found out about how to make transparent colours by flipping through Murrell (2011). The data plotted are from the NEPTUNE Canada observatory at Cambridge Bay. To see more arctic oceanographic data go to www.neptunecanada.com. Click on “DATA & TOOLS” and log in. Then click on “Data Search,” click on “Tools” and choose “Arctic Observatory.”
X <- runif(200,0,1);
Y <- runif(200,0,1);
plot(X,Y, col=rgb(0,0,1,0.5), cex=5, pch=19);
Murrell, Paul. 2011. R Graphics, 2nd Edition. CRC Press.