The Brightest Spots on Earth

[stefan]

The Brightest Spots on Earth

NASA

[stefan]

the concept of "light pollution" has been an interesting one to me as i have watched salt lake grow size and luminosity since i was a kid, year by year obscuring the stars of the night sky above the valley. i used to look up into the sky a lot. what struck me was when it became more difficult to see the stars from high points adjacent to the valley, requiring one to get further out.

if you've seen some of these images of "the earth at night," some show the sea of japan with a continuous bright glow, as bright as the cities nearby, from the reflection of the lamps of fishermen.

astronomers have the greatest stake in the issue since it affects their telescopes ... which collect light from space that is increasingly competing with the light generated on earth. this is one reason low pressure sodium lights are used primarily near observatories, since they emit only a single wavelength of light that astronomers can easily filter out.

arizona's pushed for reducing light pollution. but there are many opposing forces. it's an interesting issue, one that spreads with a growing city.

i wonder what camping on the west rim of zion will look like in 50 years

[rockgremlin]

i wonder what camping on the west rim of zion will look like in 50 years

That's another interesting phenomenon. Some areas grow/change rapidly, while other areas remain stagnant. F'rinstance go backwards 20 years and St. George would be about half? as large as it currently is. Whereas other areas look almost the same today as they did 20 years ago - Monticello, Emory, and Hanksville come to mind. And out of those three, probably the town with the most dramatic change is Hanksville, with the addition of the Chevron on the south end of town, and that little podunk motel next-door. Not too much change at all in 20 years time. Move away from the populated areas and the change is even less dramatic. There are 1000s of places in the deserts south of Price that look the same today as they did 50 - 100+ years ago. (I love that).

Another more profound form of pollution that is often overlooked is NOISE pollution.

[stefan]

That's another interesting phenomenon. Some areas grow/change rapidly, while other areas remain stagnant.


quite true.




F'rinstance go backwards 20 years and St. George would be about half? as large as it currently is.

now ya got me wondering. a quick search gave me the following numbers for population (which is one measure of "size").

St. George (within city limits) Pop.

1950 - 4,562
1960 - 5,130
1970 - 7,097
1980 - 13,300
1990 - 28,500
2000 - 49,728
2006 - 67,614

Washington County Pop. (rounded off)

1990 - 49,000
2000 - 91,100
2005 - 125,000
2007 - 140,900 (approx)



Another more profound form of pollution that is often overlooked is NOISE pollution.

very good point, one city folk have become desensitized to.

[JP]

Light pollution, ha. In the middle of the night, with no moon, you can still navigate around a lot of spots in Connecticut without a flashlight. :frustrated:

[Cirrus2000]

Another more profound form of pollution that is often overlooked is NOISE pollution.

Very true - this is something that is not often really thought about. It's amazing how much a steady background level of noise can be ignored, and yet I can't help wondering how it actually affects people.

Where I work (air traffic control tower) you expect a certain level of stress. We have an air handling unit in the ceiling of the tower 'cab', and you never really notice the level of white noise that comes out of it until it shuts off once a day for about a minute (resets or something?). When it winds down, everyone looks up, sighs, and wishes it always sounded like that. It truly feels like a big weight has been lifted off. Then it comes back... I always wonder whether everyone's blood pressure would drop by a couple of points if the AHU were elsewhere.

I also thought about this while backpacking in Grand Gulch last month. Lovely, beautiful silence but for the rustling of foliage and the calling of birds. Then every once in a while a jet flies by overhead. It's amazing how long you can hear them. I do feel a bit of conflict over that, though, as air traffic is my livelihood. I also love aviation - pretty much everything about it. Also, it's kind of nice to know that things in the outside world are going on normally (not like in the days following 9/11, for example). On the other hand, it sure would be nice to really be able to "get away from it all"...

Sorry, no citations or links or anything. Just opinion and anecdote...