Thursday, July 26, 2012

The power of scientific images

One of the leading news stories on Canada's CTV News website today was the sensationally-titled "Freak event: Ice melting nearly all over Greenland".  It was accompanied by the image shown to the left.  The map on the left half of the image looks like our usual mental picture of Greenland, with ice (white, naturally) covering most of the area.  It should be obvious that the image on the right half cannot possibly represent an ice-free Greenland (if Greenland's ice sheet had melted away, I'd be typing this right now underwater :-)   Rather, it shouldn't be hard to figure out that the warm colours must represent something like an increase in melting or melt rate.

Shown to the right is the original image from the story at the NASA website; note the legend at the bottom, which was cropped from the CTV image.  This is a perfect example of what can happen when a scientific image escapes into the public domain, where there is no guarantee that the complete story told by the image will be preserved. Of course a change in the melt rate is worrisome, but without its caption the image can easily be misinterpreted as presenting a more dire situation.  I for one will not be surprised if climate change deniers use the CTV story as a perfect example of how the media (and, naturally, its commie-pinko overlords) conspire to mislead the public about the severity of climate change. 

Who is to blame?  Well, CTV, for their sensationalistic headline and thoughtless cropping. But also  the image jockeys at NASA, usually careful about their PR (and for good rea$on$), for not considering how easy it would be to misrepresent this particular image.

Update: And so it begins -- below is a post from a user on the CTV website regarding the above story:

I hope people realize some visual mind cuing is going on here.. we associate white with snow and therefore see the red as the snow is gone.. These two red colors only represent different degrees of melting... I read the original report which printed the color index.. suspiciously missing in this photo... only the grey areas are snow free and that has not changed much .. the colors pink and red represent 'probable' melting and some surface melting (respectively) 'Some' melting meaning a few inches of surface snow on an unchanged depth of ice pack. I am willing to face facts.. but not ones twisted towards a desired opinion.. had the scale been in shades of one color it would have been much less 'dramatic' and much more accurate .. barely one shade different. I am not saying what to believe here.. but ask people to be aware that agendas are showing with how this map is being presented.