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58% of the state has gone into plaid.
Title text: 58% of the state has gone into plaid.


This graph shows the levels of drought over time in the state of California using years on the horizontal axis and latitude on the vertical axis. The image illustrates the use of the distance measure on the vertical axis by visually rotating and stacking multiple maps of California on top of each other.

The geography of California lends itself well to this kind of graphical interpretation because on a map where north is up the state is much taller than it is wide, large-scale phenomena like weather patterns are likely to cover much of the "width" of the state but only part of the "height". Because the variation in the west-east direction will be small, a side-on view of the state can be used as the vertical axis in a graph, so that the indicated values are either the average or extreme value across the width of California.

Randall compiled the data in this graph from data from the US Drought Monitor, which is authored by Richard Tinker from NOAA. The colors Randall uses correspond to drought intensity levels D0-D4 defined on the Drought Monitor site.

The graph shows that in 2000, 2005, and 2010, there were very little or no drought conditions in California, but that the intervening periods have seen increasingly severe droughts. According to the most recent data, the state is entirely in a condition of "severe" or worse drought, with "ludicrous" conditions across approximately half its area. The graph also reveals that 2014 is the first year (since 2000) where the "ludicrous" level has been seen. Indeed, a comic about drought is rather topical: California is in the middle of one of its worst droughts in recorded history.

The darkest, most severe level of drought is labelled "ludicrous" (causing laughter because of absurdity), but a parenthetical remark indicates that the official term is "exceptional.".

The title text is a reference from the movie Spaceballs, a parody of various Sci-Fi movies. Lone Starr and Barf in their Winnebago space ship traveling at warp speed are passed by Spaceball One which is traveling at ludicrous speed. The path of Spaceball One is shown as a plaid pattern and Barf remarks "They've gone to plaid!", see YouTube: Spaceballs - They've gone into plaid . With this pattern, the movie is parodying the final travel sequence of the movie 2001: A Space Odyssey.


I like how long and skinny California is because it means you can use it as a graph axis:
California Droughts
Based on map data from US Drought Monitor/NOAA/Richard Tinker
[Beige] Moderate
[Orange] Severe
[Red] Extreme
[Brown] Ludicrous ("exceptional")
[Graph showing a colored contour plot, with time in years from Jan 4, 2000 until Aug 14, 2014 on the x-axis and distance along the length of California as the y-axis, and depth of drought as the dependent variable indicated by color.]

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