I am not a gambler, except when it comes to my own life. I'm referring to my astronaut application a few years back. I was not happy the selection committee was happy for me being pregnant and used that as an excuse to not allow any further tests on me. I will forever hate that committee; but I love my son.

Anyways, I am not into gambling at all and I didn't particularly fancy going to Las Vegas, Nevada, USA. My son on the other hand, some years after he'd left my womb, found Las Vegas to be a very good idea - so we went. I brought my son with me to one of the American Geophysical Union Fall meetings in San Fransisco and rented a car so we could go after the meeting, or before, I don't recall. I do recall being pulled over by the highway patrol for speeding. I got away with it by just not speaking and flashing my non-Californian drivers license. Apparently that saved me. Not having a California license. I will remember that for my next travel with as-close-to-the-speed-of-light-as-physically-possible in California trip.

Now that I have established what a responsible mother and citizen of the world that I am, I can get to the point. Las Vegas, Baby.

I adore Las Vegas. Now. I guess for other reasons than most people. To me the place is simply fascinating as a phenomena, that collective human footprint you find one and only one of on this planet. Non describable, absolutely livable. With that in-situ experience my son and I had of the city and its surroundings, we can appreciate even more the images taken from above, the birds eye perspective of places.

NASA celebrates the 25th anniversary of Landsat-5, a satellite taking images of the Earth for various societal applications, by publishing a series of their images. I value these satellite images for their pure eye-candyness. Satellite images are pretty. Useful - but pretty!

Las Vegas in false-color images spanning from 1994 - 2009. The dark purple grid of city streets and the green of irrigated vegetation grow out in every direction into the surrounding desert.

Two series of images from this set got my special attention. The series showing the aerial growth of Las Vegas and the variations of the water level of the nearby lake Mead.

Lake Mead - A diminishing reservoir. 1990-2009.

When you build a society in the desert the water issue will be a burning hot one. Where do the citizens get their water from? There are basically two options, and rain is not one of them. Even below deserts groundwater can be found. Check for that. And you can collect water from damming natural waterways, creating so-called fake-lakes as I insist on calling them. In the Las Vegas region that fake-lake is called lake Mead. So check for that too. The control and monitoring of these sources of water will be pivotal for the Las Vegas community. And here we move beyond satellite-images are pretty and get down to serious business. The water business.

Credit: UNEP/GRIP-Arendal
The Water Cycle

With limited access to water, you'd be keen to protect your fluid treasure. Someone could be tempted to tap into your 'invisible' ground water reservoir. Who'd know, it's under ground,right? That is not such a good idea. We'll chase you down almost like they do in the CSI Las Vegas crime series on TV. Well, not the regular GPS location determination by hooking a receiver onto your car, but with high geodetic precision we can monitor distortions of the terrestrial crust down to the millimeter. If you tap your groundwater the resulting void leads to subsidence. It'll not be caught on film, but caught on GPS! And then perhaps we'd hook you up with a GPS receiver and chase you. GPS is however not the only geodetic tool we use when we want to take a really close look at the displacements, we also have SAR interferometry. I promise you'll hear more about that later.

If you look at Las Vegas from a global perspective it doesn't seem that bad. (But it is):

Credit: UNEP/GRID-Arendal
Water scarcity occurs when the amount of water withdrawn from lakes, rivers or groundwater is so great that water supplies are no longer adequate to satisfy all human or ecosystem requirements, resulting in increased competition between water users and other demands.

In The Late Show with David Letterman the multimillionaire Donald Trump complained about the lousy state of the gambling industry and used that as a sorry excuse for making less millions than he usually does. I believe the bottom line of the gambling industry will be the least of your problems when you reach the bottom line of the groundwater in Vegas.

So there you go. Las Vegas, Baby.

Relevant information about sustainable water management:
IGCP 565: Supporting water resource management with improved Earth observations
Water and Population
The World's Water