• ES Picture of the Day 29 2020

    From Black Panther@21:1/186 to All on Thu Oct 29 11:00:30 2020
    EPOD - a service of USRA

    The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
    captions and links exemplifying features within the Earth system. The
    community is invited to contribute digital imagery, short captions and
    relevant links.


    The Shrinking Great Salt Lake

    October 29, 2020

    Gsldavisky796c_26july20

    Photographer: Ray Boren
    Summary Author: Ray Boren

    As with other closed-basin endorheic, or terminal, lakes
    around the world — often in arid or semi-arid climates,
    from Africa’s Lake Chad to central Asia’s Aral Sea — North
    America’s Great Salt Lake is out of balance and shrinking in size
    and storage. This is due in part to climate change but more
    particularly, hydrologists and other researchers say, because of human
    damming and upstream diversion of its water sources for agriculture and
    urban uses.

    One result, as shown in this photograph, looking west from near the top
    of Utah’s Wasatch Range on July 26, 2020, is a depleted Farmington
    Bay. The lagoons in the middle of the picture are primarily diked
    fresh-water impoundments of Utah’s Farmington Bay Waterfowl
    Management Area, a key habitat for migrating and nesting birds.
    Otherwise, a small and sinuous river of lake water winds through the
    desiccated eastern lake bed and mudflats toward Antelope Island,
    the lake’s largest isle and a state park. Deeper water is visible
    beyond the island in Great Salt Lake’s central Gilbert Bay.

    According to the US Geological Survey, the average surface
    elevation above sea level of Great Salt Lake — itself a remnant of the
    Pleistocene’s much larger Lake Bonneville — is 4,200 ft
    (1,280 m), at which point it covers about 1,700 sq mi (4,403 sq km). In
    the mid-1980s, as a result of several years with above-average
    precipitation, the lake elevation surged to 4,211.6 ft (1,283.7 m),
    with a much-expanded surface area of 3,300 sq mi (8,547 sq km). It was
    at its lowest historic surface elevation in 1963, when it dipped to
    4,191 ft (1277.4 m) and covered only 950 sq mi (2,460.5 sq km) — a
    status Great Salt Lake has again approached in recent years. In
    September 2020, the USGS recorded the lake surface elevation at
    4,193 ft (1,278 m) above sea level. In addition, the National
    Oceanic and Atmospheric Administration reported this summer that 68
    percent of the Western United States, including Utah, is again in
    drought.

    Photo Details: Camera NIKON D3200; Exposure Time 0.0020s (1/500);
    Aperture ƒ/11.0; ISO equivalent 360; Focal Length (35mm) 105.
    * Farmington Bay, Utah Coordinates: 41.03738, -112.15494

    Related EPODs

    The Shrinking Great Salt Lake Mass Balance Archive -
    Longest Day Ice Out on Sebago Lake in 2020 Archive -
    Breidamerkurjökull Ice Cap Death Valley’s Zabriskie Point

    Climatology Links

    * Aerosols: Tiny Particles, Big Impact
    * JetStream - An Online School for Weather
    * Climate History
    * National Centers for Environmental Information
    * Global Climate Animations
    * NOAA Climate Analysis Branch
    * Vital Climate Graphics

    -
    Earth Science Picture of the Day is a service of the Universities
    Space Research Association.

    https://epod.usra.edu

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  • From Black Panther@21:1/186 to All on Sun Nov 29 11:00:58 2020
    EPOD - a service of USRA

    The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory
    captions and links exemplifying features within the Earth system. The
    community is invited to contribute digital imagery, short captions and
    relevant links.


    Archive - Lenticular Cloud Display

    November 28, 2020

    02clouds copy

    Every weekend we present a notable item from our archives. This EPOD
    was originally published November 28, 2003.

    Provided and copyright: Bill Willenberg
    Summary authors & editors: Bill Willenberg; Jim Foster

    The above photo shows but a glimpse of a spectacular lenticular cloud
    display, captured late in the day in mid-October, northwest of Salem,
    Oregon. This 8-layer cloud stack was the finale of a delightful
    orographic concert. On this particular afternoon, lenticular clouds
    were observed over the Willamette Valley, the Cascades Range (east of
    Salem) and the Salem Hills (south of Salem), but the few lenticular
    stacks that formed were confined to Oregon's coastal range and the Eola
    Hills. Lens-shaped lenticular clouds can form when moist air is cooled
    to the dewpoint as it's forced up over mountain slopes -- wherever
    stable moist air flows over a mountain range. As this happens,
    sometimes a series of wave clouds are created on the downwind or lee
    side of the range. If conditions are just right (moist layers are in
    rather close proximity), the clouds can appear to stack upon one
    another.


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    Clouds Above Antarctica EPOD 20th - Foggy Start to the Day in
    Budapest, Hungary Encore - Morning Glory Over Southeastern Brazil
    More...

    Cloud Links

    * Atmospheric Optics
    * The Cloud Appreciation Society
    * Cloud Atlas
    * Color and Light in Nature

    -
    Earth Science Picture of the Day is a service of the Universities
    Space Research Association.

    https://epod.usra.edu

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    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)