Ever since my grandmother got my dad subscriptions when I was a kid to now when it comes to me directly, I have been a long-time subscriber to National Geographic Magazine. The September, 2013 issue arrived recently and has for it’s main story the rising of the oceans due to polar ice melting. Inspired, I set out to create a set of graphics that can be used to demonstrate the effects of the rising seas.
I had done this before back in 2011 with a simple image that combined Blue Marble imagery with ETOPO1 digital elevation model dataset and doing some research on Wikipedia. That research led me to estimate the extent of sea level rise to 67.5 meters (221.5 ft). The poster in this month’s National Geographic appeared to pretty much do the same thing data-wise, just as a globe, and it looked a heck of a lot better. The National Geographic article quotes a rise of 65.8 meters (216 ft) with the complete melting of the Antarctic and Greenland ice sheets. I was close, but I’m just as happy to defer to the folks at NGM, the NOAA, the Woods Hold Research Center, and University of California, Santa Cruz. My goal was to create and extend the graphics in the magazine poster, but recreating the same exact images wouldn’t be much interesting, original, or fun, and would probably just earn me a nastygram from the original authors.
I won’t go into much of the science or politics involved in global warming and it’s effects on the polar ice caps. There are much better and much more qualified folks for that (Phil Plait or Sheril Kirshenbaum, to name two (Not my normal field of study so please excuse the ignorance in who the major players are)). I’m into the technical challenges in creating the visualizations; I am a software engineer and not a scientist. I hope to be as accurate as possible, but if I do goof something up, there’s my excuse.
The process in creating my set of image layers was pretty similar to what I had done before. I used a bit of software I had written called jDem846 to render the ocean bathymetry model, along with the files I would need for the 3D projections: normal maps, bump/displacement maps, and specular maps. I used GIMP to combine some of the bathymetry and Blue Marble layers, and create the shoreline outlines and coloring. GIMP also proved very capable for drawing some green over Greenland, Canada, Alaska, Siberia, and Antartica (you know, ’cause the ice melted and all).
The final globes are done by dropping the 3D assets into another bit of code I had written called PlanetMaker. As you might guess, PlanetMaker is for using aspects of computer graphics with imagination for rendering custom planets. It makes use of WebGL, and works in Google Chrome, and for the most part, Firefox.
Ok, now for the images. All these images are licensed for Creative Commons Attribute-ShareAlike.
|Bathymetric Oceans (No Clouds)|
|Opaque Ocean (No Clouds)|
|Seacoast Outlines (No Clouds)|
|Surface Texture with Bathymetric Ocean||8192x4096 JPG 28MB
4096x2048 JPG 9.5MB
2048x1024 JPG 2.7MB
1024x512 JPG 709KB
512x256 JPG 181KB
|Surface Texture||8192x4096 JPG 11MB
4096x2048 JPG 3.8MB
2048x1024 JPG 1.2MB
1024x512 JPG 359KB
512x256 JPG 107KB
|Surface Texture with Current Seacoasts Outlined||8192x4096 JPG 29MB
4096x2048 JPG 9.8MB
2048x1024 JPG 2.8MB
1024x512 JPG 727KB
512x256 JPG 185KB
|Normal Map||8192x4096 JPG 1.8MB
4096x2048 JPG 404KB
2048x1024 JPG 89KB
1024x512 JPG 19KB
512x256 JPG 4KB
|Bump/Displacement Map||8192x4096 JPG 696KB
4096x2048 JPG 110KB
2048x1024 JPG 35KB
1024x512 JPG 12KB
512x256 JPG 3.9KB
|Specular Map||8192x4096 JPG 2.8MB
4096x2048 JPG 1.2MB
2048x1024 JPG 429KB
1024x512 JPG 155KB
512x256 JPG 55KB
|Lost Landmass||8192x4096 JPG 3.8MB
4096x2048 JPG 1.4MB
2048x1024 JPG 486KB
1024x512 JPG 172KB
512x256 JPG 61KB