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‘Dirty Snow’

‘Dirty Snow’

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‘Dirty Snow’

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  1. Dust on snow Clean snow ~1 m (3 ft) higher than dusty snow after 30 days!! Photos courtesy Tom Painter ‘Dirty Snow’ Profound impacts to regional water resources (storage, timing of peak flow, hydro-electric power generation, ecosystem). Observations suggest that regional dust-on-snow events have increased in frequency over the past 7 years…

  2. Snow/Cloud Discrimination • High spatial resolution snow cover improved via cirrus filtering using the 1.38 m band Miller, S. D., 2005, JAM 44(7), 987-997

  3. A major dust storm in China made its way off the Asian continent on April 1st. • Timing would be right for a Colorado appearance ~ April 6th. Intercontinental Dust Transport Local CO news headlines exclaim: “Mongolian Dust Hits Colorado!!” Beijing, China ??? Evergreen, Colorado Dusty Snow, Aspen Mtn. Example of trans-Pacific dust transport (NASA) East Asia A story of “East Meets West”? Or…

  4. “Fluorescent Sand” Excitation Wavelength = 410 nm 0.5 mm  Fluorescent minerals…a ‘So What?’, or information content to be exploited by future R/S…?

  5. Dust Enhancement (Pink) Aqua 7/2/2010 1015 UTC Iraqi Shamal True Color

  6. Discrete Sources Lofting from Point Sources

  7. 2007 Southern California Fires & Dust

  8. Volcanic Ash Detection Eyjafjallajökull 18 April 2010

  9. Pumice Raft Ship Photos pumice Pumice Rafts: “Drifting Islands”  A floating island of pumice produced during island formation at Home Reef (near Tonga). Silicon dioxide and iron oxide content results in preferential blue-light absorption, allowing for enhancement by simple MODIS Red/Blue ratio techniques.

  10. Oil Slick Detection from MODIS Observations in Sun Glint BP Deep Water Horizon Explosion 21 April 2010 Photos: Associated Press

  11. First Indication of a Slick Cirrus Shadow Cirrus Oil Slick Terra/MODIS: April 22, 2010, 1645 UTC Aqua/MODIS: April 21, 2010, 1920 UTC

  12. Evolution of Slick

  13. Visible Data Infrared Data Solar Zenith Weighting True Color Background Night Lights Background Blended VIS/IR/Background ‘GeoColor’

  14. Hurricane Katrinain GeoColor GOES-12: Aug 27 0015Z – Aug 29 1815Z

  15. Three-Layer GeoColor Example

  16. . * . . . . . . . . . . * . . . Nocturnal Excursus… . * . . . . . . . . . . . . . . . . . . . “Milky Seas” A New Science Frontier Enabled by Nighttime Low-Light Visible Remote Sensing Technology . . * . * Miller, S.D., et al., 2005, Proc. Nat. Acad. Sci., 102(40), 14181-14184. Miller, S. D., et al., 2006, Int. J. Rem. Sensing, 27, 5131-5143.

  17. ‘Beautiful’ Manatees Toy Submarine Lifetime Supply of Calamari Maritime Folklore: Degrees of Truth Monsters…? Mermaids…? Man Eaters…? Confirmed Half Truths Hoaxes

  18. What Are ‘Milky Seas’? • Term coined by sailors to describe surreal encounters with massive (horizon-to-horizon) regions of glowing seawater. • Produce a steady glow comparable to snow or cloud fields, with viscosity likened to ‘thick cream’ or ‘molten lead’. • Over 230 events reported since 1915, most in the NW Indian Ocean and Indonesian waters (Herring and Watson, 1993). • Single encounter by research vessel (Lapota et al. 1988) in Arabian Sea found luminous bacteria colonizing algal bloom. • Never before photographed or captured via remote sensing. • Circumstances surrounding their cause and reasons for occurring are almost entirely unknown.

  19. “About seven o’clock in the evening, the Nautilus, half-immersed, was sailing in a sea of milk. At first sight the ocean seemed lactified (...) The whole sky, though lit by the sidereal rays, seemed black by contrast with the whiteness of the waters. (…) Conseil could not believe his eyes, and questioned me as to the cause of this strange phenomenon. Happily I was able to answer him. ‘It is called a milk sea’…” J. Verne’s Twenty Thousand Leagues Under the Seas. “…let him be called from his hammock to view his ship sailing through a midnight sea of milky whiteness -as if from encircling headlands shoals of combed white bears were swimming round him, then he feels a silent, superstitious dread…” H. Melville’s Moby Dick Truth Inspiring Fiction…

  20. The S.S. Lima 1995 Account “At 1800 UTC on a clear moonless night while 150 n.mile east of the Somalian coast a whitish glow was observed on the horizon and, after 15 minutes of steaming, the ship was completely surrounded by a sea of milky-white colour with a fairly uniform luminescence. The bioluminescence appeared to cover the entire sea area, from horizon to horizon […] and it appeared as though the ship was sailing over a field of snow or gliding over the clouds […] The bow waves and the wake appeared blackish in colour and thick black patches of oil were passing by. Later, the Aldis lamp revealed that the ‘oil patches’ were actually light green kelp, amazingly black against the white water.” —Capt James Briand, S.S. Lima; Marine Observer, 66, 12-13, 1996

  21. 25 Jan 1995 1836 GMT 26 Jan 1995 1804 GMT 27 Jan 1995 1725 GMT 28 Jan 1995 1841 GMT Detection of a Persistent Anomaly Socotra INDIAN OCEAN SOMALIA Raw DMSP/OLS DATA

  22. Digital Enhancement • Subtracted mean from each scan line • Applied simple 3x3 pixel spatial coherence filter • 8-pixel boxcar average in scan & track directions • Histogram equalization

  23. 100 km (~ 150 km of travel)

  24. Spatial Evolution of Feature Cold Core Eddy

  25. 2. ‘Quorum sensing’ occurs when cell populations exceed 108 cells/mL, triggering localized light production. Above: A population explosion of Vibrio fischeri bacteria colonizing a nutrient-rich photobacterium broth. Hypothesis: A ‘White Tide’? • Nutrient rich upwelling waters and cold ring accumulation zones offer ideal habitats for phytoplankton blooms, which then serve as focal points for bacterial colonization (either in association or breakdown) 3. Growing bacterial colony secretes increasing levels of autoinducer into environment–stimulating further bioluminescence. 4. Scotopic (night/low-light) vision may explain the ‘milky white’ (vs. blue/green) appearance to human observers.

  26. Milky Seas: Summary There are massive light displays being produced in Earth’s oceans whose exact cause and purpose remain uncertain. Luminous bacteria blooms communicating via quorum sensing offer a plausible explanation for the steady glow. Awaiting launch of VIIRS/DNB on NPP and the potential ability to confirm future sightings. Our Planet Harbors Many Great Mysteries Still Unsolved! Jules Verne

  27. Parting Thought One World, Many Perspectives… Communicating Scientific Information is an Art Form!