Not to be a killjoy, but AFAIK you can't actually see the lights from space the way this is depicted.
Article on how the image was made: http://earthobservatory.nasa.gov/Features/Lights/
from page 2
So at best, take artistic license and just make it "look good".The images were taken by a Defense Meteorological Satellite Program’s (DMSP) Operational Linescan System (OLS). This network of satellites was originally designed to pick up on lunar illumination reflecting off of clouds at night in order to aid nighttime aircraft navigation. What the Air Force discovered is that on evenings when there was a new moon, the satellites were sensitive enough to record the illumination from city lights. Over a period of several new moons, the data the satellites retrieved could be pieced together to produce a global image of city lights.
-Rob A>