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.


Snow, Clouds and Light on a Winter's Day

February 05, 2020

FlatPassApproachCloudsAndSnowRipplesByMikeSanchez

Photographer: Michael Sanchez; Skier: Stan Wagon
Summary Authors: Jim Foster; Stan Wagon

The photo above showing a wintry scene and a wavy sky was taken four
miles north of Vail Pass, Colorado, on January 5, 2020. Sculpted by
wind after a recent snowfall, the ripples are called sastrugi. The
altostratus clouds seem to mimic the rippled patterns of the snowy
landscape and are just thin enough to permit the Sun to peek through.

Because snow crystals are large compared to the wavelengths of
visible light, sunlight is more effectively scattered in a forward
direction -- the scene seems brighter, with less contrast, when facing
the Sun. However, since this snow surface appears corrugated, light is
both forward-scattered and backscattered when looking toward the
Sun. Of course, a cloudy sky, as is the case here, noticeably dampens
this effect. On his alpine touring skis, Stan Wagon is taking in all
that this winter’s day has to offer.
* Vail Pass, Colorado Coordinates: 39.5293, -106.2176

Related EPODs

Snow, Clouds and Light on a Winter's Day Abstract Ice Pattern
on Pond Snowflake Sampler Archive - Explaining Ring Patterns in
a Frozen Puddle Encore - Snow Eyes Icy Drops
More...

Cryosphere Links

* Guide to Frost
* What is the Cryosphere?
* Bentley Snow Crystals
* Glaciers of the World
* Ice, Snow, and Glaciers: The Water Cycle
* The National Snow and Ice Data Center Google Earth Images
* Snow and Ice Crystals

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

https://epod.usra.edu

--- up 2 weeks, 15 hours, 4 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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.


Halo Formation above Cadini di Misurina, Italy

March 05, 2020

Panoramica_ completa 2 firma picc (002)

Photographer: Giorgia Hofer
Summary Author: Giorgia Hofer

The halo complex featured above was captured above Cadini di
Misurina in Italy, on January 25, 2020. The weather forecast for this
midwinter day didn’t seem favorable for atmospheric optics, but I’ve
learned that even when the weather is unfavorable, it’s always best to
make sure my camera is with me. Before the poor weather set in, limited
sunshine and oriented ice crystals, composing cirrus
clouds, put on a memorable show.

The vivid colorful strip at top-center is a circumzenithal arc;
bright sundogs flank either side of the Sun (both with extended
tails); tangent to the circumzenithal arc and curving toward the
surface is a much fainter supralateral arc, and between this arc
and the Sun is a suncave arc or Parry arc.

Photo Details: Camera: Canon PowerShot G7 X Mark II; Software: Adobe
Photoshop CC 2015 (Windows); Exposure Time: 0.0005s (1/2000); Aperture:
ƒ/11.0; ISO equivalent: 125; Focal Length: 8.8mm.
* Cadini di Misurina, Italy Coordinates: 46.583288, 12.191391

Related EPODs

Halo Formation above Cadini di Misurina, Italy Encore - Upper
Tangent Arc, Halo, Sundogs and Glitter Path Observed from Vancouver
Encore - Fogbow Near Mount Luxmore, New Zealand Corona Over
Westmoreland State Park, Virginia Twilight Sky at Mont-Saint-Michel
Red Sprites and Airglow
More...

Atmospheric Effects Links

* Atmospheric Optics
* Color and Light in Nature
* The Colors of Twillight and Sunset
* Refraction Index
* Image Gallery: Atmospheric Effects
* What is a Rainbow?

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

https://epod.usra.edu

--- up 6 weeks, 1 day, 15 hours, 5 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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 - Hudson Highlands

April 05, 2020

Hudsonhighlands

Each Sunday we present a notable item from our archives. This EPOD was
originally published April 5, 2004.

Provided and copyright by: Karl Tsakos, Bedford Central Schools
Summary author: Steve Kluge

This view north across the Hudson Highlands of New York State was taken
from Bald Mountain in Bear Mountain State Park. The rugged landscape,
only 37 miles (60 km) north of New York City, is developed on very old
(Precambrian) and very resistant metamorphic rocks. These rocks are
estimated to be between 1.1 and 1.3 billion years old, deformed along
with the rocks of the Adirondack Mountains during the Grenville
Orogeny. The narrow and winding course of the Hudson in this area is
fascinating, especially considering the fact that the river is actually
an estuary here, having already reached sea level at Newburgh, NY,
several miles to the north. The river is significantly wider, and the
shorelines more gently sloping, both north and south of the Highlands.

This interesting geomorphology played a significant role in the outcome
of the Revolutionary War, where just south of the present-day Bear
Mountain Bridge, the colonial forces built a chain floating on large
logs across the Hudson to halt the advance of the British fleet into
the interior of the territory. Several forts were built along the river
in the highlands (the U.S. Military Academy at West Point is just
around the bend in the river at the top of the photo), and
communications were accomplished by a series of signal fires at the
tops of the peaks along the river. The names of the town of Beacon and
Beacon Mountain just north of here recall that history.


Related EPODs

Archive - Hudson Highlands Archive - Eureka Dunes in Death
Valley, California Limestone Pavement at Malham Cove Encore -
Eruption of Mount Yasur in Vanuatu Volcán de Fuego Active Again
Archive - Gneiss Outcrop in Montana
More...

Geology Links

* Earthquakes
* Geologic Time
* Geomagnetism
* General Dictionary of Geology
* Mineral and Locality Database
* Mohs Scale of Mineral Hardness
* This Dynamic Earth
* USGS
* USGS Ask a Geologist
* USGS/NPS Geologic Glossary
* USGS Volcano Hazards Program

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

https://epod.usra.edu

--- up 10 weeks, 4 days, 14 hours, 5 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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.


One View, Four Rainbows

June 05, 2020

Image0

Photographer: Jim Grant
Summary Authors: Jim Grant, Jim Foster

I had no idea when I walked along the beach this April morning that I’d
be confronted by these stunning rainbows. Both the primary
rainbow and the secondary bow are reflected in the wet sand.
The Sun is opposite of where the camera is pointing.

After sunlight has been reflected inside the raindrops (producing
the primary and secondary bows) it’s then reflected by the wet sand.
This reflection inverts what we see in the sky. Whereas the primary
rainbow’s center is below the horizon ( antisolar point), the
inverted bow’s center is actually above the horizon at the same
altitude of the Sun (antihelic point). Note that reflected rainbows are
entirely different than reflection rainbows. Photo taken on Ocean
Beach pier in San Diego, California, on April 9, 2020.
* Ocean Beach Pier, California Coordinates: 32.74963, -117.25759

Related EPODs

One View, Four Rainbows Anticrepuscular Rays and Lunar Eclipse
Encore - Summer Lightning in Florida Twilight Times: Civil,
Nautical and Astronomical Approach of Storm and Lunar Halo Low
Bow Over La Palma
More...

Atmospheric Effects Links

* Atmospheric Optics
* Color and Light in Nature
* The Colors of Twillight and Sunset
* Refraction Index
* Image Gallery: Atmospheric Effects
* What is a Rainbow?

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

https://epod.usra.edu

--- up 19 weeks, 2 days, 16 hours, 4 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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 - Joshua Tree National Park

July 05, 2020

Submission copy

Each Sunday we present a notable item from our archives. This EPOD was
originally published July 6, 2003.

Provided and copyright by: Jacob Sears
Summary authors & editors: Jacob Sears; National Park Service

The photo above was taken in Joshua Tree National Park in California.
The plant in the foreground is a California Barrel Cactus (Ferocactus
cylindraceus). Joshua Tree Park consists of two somewhat distinct
desert ecosystems. To the west is the lower (below 3,000 ft or about
915 m) and hotter Colorado desert, and to the east is the slightly
higher and more moist Mojave Desert. Geologists believe that the face
of this fascinating landscape was formed more than 1 million years ago.
In more recent times (past 10,000 years or so), flash floods have
washed away soil and sand layers, exposing boulders which had been
eroded tens of thousands of years earlier. Powerful floodwaters piled
the boulders on top of another, creating the impressive rock piles we
see today (background).


Related EPODs

Archive - Joshua Tree National Park Yorkshire Limestone
Pavement Cyclops Islands Marine Protected Area The Stone Face
of the Uinta Mountains Encore - Position of the Setting Sun
Mount Ararat at Sunset
More...

Geography Links

* Atlapedia Online
* CountryReports
* GPS Visualizer
* Holt Rinehart Winston World Atlas
* Mapping Our World
* Perry-Castañeda Library Map Collection
* Types of Land
* World Mapper

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

https://epod.usra.edu

--- up 23 weeks, 4 days, 16 hours, 5 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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.


Altocumulus Formation

August 05, 2020

29042020-SS29042020-DSC_3117SoniLu

Photographer: Sonia Lucía Suárez Domínguez
Summary Authors: Sonia Lucía Suárez Domínguez; Jim Foster

The photo above shows an eye-catching cloud formation that I observed
over the sea, off La Palma island (Canary Islands, Spain), shortly
after sunrise. These are mid-level altocumulus clouds. They may
have formed as an altostratus cloud deck began to dissipate. When
the Sun’s low in the sky, gray shading is often noted. Photo taken
on April 29, 2020.

Photo Details: Camera NIKON D3100; Software Adobe Photoshop Lightroom
6.0 (Windows); Exposure Time 0.0008s (1/1250); Aperture ƒ/11.0; ISO
equivalent 100; Focal Length (35mm) 24.
* Villa de Mazo, Spain Coordinates: 28.6221, -17.7807

Related EPODs

Altocumulus Formation Cirrus Rows Building Storm Near Belo
Horizonte Brazil Trade Winds and Clouds on La Palma Santa Ana
Wave Clouds Sierra Wave
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

--- up 2 weeks, 6 days, 15 hours, 25 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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.


EPOD 20th - Microscopic View of Frost on Blade of Grass

September 05, 2020

Capture
We’re celebrating 20 years of Earth Science Picture of the Day during
the month of September! Today’s photo features a popular EPOD from the
past. Thanks to all of our followers (on the blog, Facebook, Instagram
and Twitter) for supporting us. Thanks also to all of you who’ve
submitted your photos. We’re most appreciative. This EPOD was
originally published March 17, 2004.

Provided by: Eric Erbe
Summary authors & editors: Eric Erbe; Jim Foster

The spectacular image above shows morning frost on a blade of grass as
imaged using a low-temperature scanning electron microscope (SEM). This
grass fragment was held in liquid nitrogen (-196 degrees C or -320 F),
to keep the frost crystals from melting, before it was imaged at the
Scanning Electron Microscopy Laboratory in Beltsville, Maryland. Frost
crystals form perpendicular to individual blades of grass. Note that
although these plate type crystals are hexagonal, a number of them
appear to be square-shaped.


Related EPODs

EPOD 20th - Microscopic View of Frost on Blade of Grass Archive
- Avalanche Pass and Hanging Valley Freshwater Over-layering
Saltwater Unusual Snow Crystals The Harding Icefield
Hoarfrost Flowers and Frozen Ripples
More...

Cryosphere Links

* Guide to Frost
* What is the Cryosphere?
* Bentley Snow Crystals
* Glaciers of the World
* Ice, Snow, and Glaciers: The Water Cycle
* The National Snow and Ice Data Center Google Earth Images
* Snow and Ice Crystals

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

https://epod.usra.edu

--- up 1 week, 4 days, 20 hours, 20 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)

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.


Sun Pillar at Dawn Above Turin, Italy

October 05, 2020

Sun Pillar over river Po

Photographer: Stefano De Rosa;
Summary Author: Stefano De Rosa

The photo above shows a splendid sun pillar as observed above
Turin, Italy, just before dawn on July 6, 2020. Its subtle light can be
seen reflecting in the Po River. Sun pillars result from
the reflection of sunlight off ice crystals in the
atmosphere, either suspended in the atmosphere or in cirrus
clouds. It should be noted, though, that in order to see these pillars,
the crystals need to be slightly tilted in the direction of the
observer. At right center, the silhouetted Church of Santa Maria al
Monte dei Cappuccini can be seen on a hillside overlooking the Po
River. Photo taken on July 6, 2020.

Photo Details: Canon EOS 5D Mk II camera; Canon EF 24-105mm lens; 24mm;
1/80 second exposure; ISO 160; f/5.6.
* Turin, Italy Coordinates: 45.059722, 7.697222

Related EPODs

Sun Pillar at Dawn Above Turin, Italy Encore - Exploding Meteor
Over Northern Michigan EPOD 20th - Circumhorizontal Arc Above
Pilesgrove, New Jersey EPOD 20th - Anticrepuscular Rays Observed
Over Miami Beach, Florida EPOD 20th - Shimmer Tree EPOD 20th -
Inferior Mirage of a Ship
More...

Atmospheric Effects Links

* Atmospheric Optics
* Color and Light in Nature
* The Colors of Twillight and Sunset
* Refraction Index
* Image Gallery: Atmospheric Effects
* What is a Rainbow?

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

https://epod.usra.edu

--- up 5 weeks, 6 days, 20 hours, 26 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (21:1/186)