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Salt Lake City from LandSat

Posted by michael on from the ringside-seats dept.

Radiogal writes: "A great view of the area from NASA! See olympics.gsfc.nasa.gov." This is about all of the Olympics you're going to see on the web. :)

4 of 15 comments (clear)

  1. More content coming Friday by minervaz · · Score: 2, Informative

    There will be more content coming up on the site on Friday afternoon -- zooms from space into the various sites around Salt Lake City.

  2. Temperature Inversions by swillden · · Score: 4, Informative

    You can't see much from space this week.. the temperature inversion is awful. You can't even see our beautiful mountains.

    For any of you who are wondering what flikx is talking about:

    The Salt Lake Valley is surrounded on the east and the west by tall mountains, and the exits from the valley on the north and south are relatively narrow. The effect is almost like a big bowl. Fairly frequently during the winter a pocket of warmer air gets trapped in the bowl underneath a layer of cold air. This situation is called a temperature inversion.

    The problem with this situation is that the cold air acts like a lid on the valley, trapping all of the smog produced by cars, refineries, factories, etc. When this situation persists for more than a few days it can get pretty bad. Not L.A. kind of bad, but thick enough that it does ruin the view, and bad enough that use of wood-burning stoves and fireplaces are disallowed to help keep us from exceeding EPA regulations on particulate matter (and we still do, at times). The haze stays high enough that it doesn't really affect people, just the visibility.

    Unfortunately, after several weeks of record cold, but quite clear, weather, an inversion began a few days back, and there's no telling how long it will persist. Up in the mountains at the ski resorts where the downhill events are will be clear and typically beautiful, but the medals plaza, skating rinks, hockey, etc. will be shrouded in brown smog.

    Too bad, really, but there's nothing to be done. A good snowstorm will both scrub the haze from the air and has a good chance of breaking the inversion, so that's our best hope. There is a storm on the forecast for Friday morning, which would be perfect. The view of the mountains from the valley is absolutely spectacular when the air is clear.

    --
    Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
    1. Re:Temperature Inversions by Conor · · Score: 3, Informative

      A temperature inversion occurs when a layer of cold air is trapped below a layer of warmer air. Thus the air temperature increases with altitude, which is not usually the case. This is often due to a high pressure region in the winter, which traps the air close to the ground. Since the cold air is less bouyant than the warm air above, the normal convection process stops working and a build-up of pollutants occurs. A strong horizontal wind is needed to clear out the cold, dirty air from the city.

  3. Re:All right! by robsimmon · · Score: 2, Informative

    At least two of the satellites involved--Terra [with the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument] and Landsat 7 [with the Enhanced Thematic Mapper plus (ETM+)]--have an orbital revisit of once every 16 days. Due to the field of view, low resolution data - 250 km per pixel (MODIS) - is produced every day or so. Medium resolution (15 meters per pixel, ETM+) every 16 days (well, maybe 9). IKONOS, which provides 1 meter data, is a commerical mission, and I don't know the specifics, but the revisit time is even less frequent.

    http://earthobservatory.nasa.gov/Library/AM1/
    http://earthobservatory.nasa.gov/Library/Landsat/

    and in response to the target remark, we are no longer allowed to post labelled satellite images of NASA centers.

    More cool related imagery (shameless plug): http://earthobservatory.nasa.gov/Newsroom/BlueMarb le/