Or, “how to hide the decline with color”.
Here’s the image and press release from NOAA NNVL this week to push their hurricane season announcement. Notice anything odd?
Weakening of La Niña but Above Normal Hurricane Season is Predicted
[Thursday] NOAA issued the 2011 Atlantic Hurricane Season Outlook, which predicts an above-normal year for activity. Though the La Niña continues to weaken in the Pacific, it will continue to effect weather patterns and influence the number of storms that are predicted. During La Niña years, wind shear is reduced in the Tropical Atlantic, creating conditions that are ideal for tropical cyclone formation. This image shows how the sea surface temperatures have changed, on average, from mid-April to mid-May. A warming signature is clearly visible as indicated by the red areas in the Eastern Equatorial Pacific region, an indication of La Niña’s waning strength. Also related to the Atlantic Hurricane Season, warming trends are visible in the Caribbean and Eastern Gulf of Mexico.
To be fair, the top image this week from NNVL is about the change in SST, while the two examples above are the current SST. The point I’m trying to illustrate is not about the data, but about the choice of color used to visualize the data.
It sure is easy to make something look weak (or weakening, a word they use in the press release) if you wash it out like NOAA did with their top image. Note that their color scale (shown below for the La Niña is weakening image) is highly biased towards white, showing only the most extreme temperature in colors:
I wonder what the scale might look like when we have a strong El Niño heating up the planet?
Oh, wait, been there, done that. Here’s the image from NNVL when El Niño was on:
Gosh, El Niño looks angry and threatening doesn’t it? All those fiery reds, yellows and oranges.
Now let’s look at how they communicate a “cool” La Niña in Sept 2010:
Notice how the red/blue color scale is
inverted expanded, compared to the one they used this week, with the neutral white being just a notch on the scale. And for some bizarre reason, they decided to include land temperatures with SST…which they didn’t do in the other images above. The result is the planet still is filled with raging red when trying to communicate a cool SST event.
What we have here, is failure to communicate a concept consistently with color. Imagine the confusion if Unisys or other SST product imagers changed their colors with each image release? So far, NOAA NNVL has not been able to present a consistent color scheme for images that will be mass distributed to the public and press. Each visualization has a different color key.
I think NOAA NNVL should standardize on a SST color palette scheme no matter what the ocean conditions are. Next time we have an El Niño event, and these guys image it, let’s make sure we remind them that they need to be consistent.
Of course, this visualization group has been caught playing tricky pix before, so they may not care, see the before and after when WUWT put then on notice:
Next time they image ENSO in color, let’s “help them get their mind right”. Cool, cool hand NOAA.