The GeoChristian

The Earth. Christianity. They go together.

A river runs through it — on Titan

The Cassini probe, in orbit around Saturn, has captured a new radar image showing a long river on Titan, Saturn’s largest moon.

From the European Space Agency:

“The international Cassini mission has spotted what appears to be a miniature extraterrestrial version of the Nile River: a river valley on Saturn’s moon Titan that stretches more than 400 km from its ‘headwaters’ to a large sea.

It is the first time images have revealed a river system this vast and in such high resolution anywhere beyond Earth.

Scientists deduce that the river is filled with liquid because it appears dark along its entire extent in the high-resolution radar image, indicating a smooth surface.

[…]

Titan is the only other world we know of that has stable liquid on its surface. While Earth’s hydrologic cycle relies on water, Titan’s equivalent cycle involves hydrocarbons such as ethane and methane.

Images from Cassini’s visible-light cameras in late 2010 revealed regions that darkened after recent rainfall.”

HT: Clastic Detritus

Grace and Peace

December 17, 2012 Posted by | Astronomy, Geology, Imagery, Planetary Geology | , , , , | Leave a comment

Earth at Night

NASA recently released Earth at Night, a global view of the planet at night, with city lights, oilfield flares, night time fishing fleets, and auroras.

Google has created a wonderful viewer for this data, which can be found at its Earth at Night 2012 site.

Earth at Night zoomed out to show the entire planet

Earth at Night zoomed out to show the entire planet

Northeast United States

Northeast United States

Montana, where night skies are always black

Montana, where night skies are always black

Netherlands, Belgium, and northern France, where you would be lucky to see Jupiter on a cloudless night

Netherlands, Belgium, and northern France, where you would be lucky to see Jupiter on a cloudless night

Korean Peninsula. Note the lights from fishing fleets off the coast of South Korea. Note also how dark North Korea is.

Korean Peninsula. Note the lights from fishing fleets off the coast of South Korea. Note also how dark North Korea is.

Grace and Peace

December 17, 2012 Posted by | Geography, Imagery | | Leave a comment

NASA Earth Observatory — Images from November 2012

From NASA Earth Observatory’s Image of the Day — my favorites for November 2012:

A Changed Coastline in New Jersey — These images show why building (or rebuilding) on a barrier island is not a really good idea. These two aerial photos show a view of Mantoloking, New Jersey before and after “Superstorm” Sandy in October, 2012.

date

March 18, 2007

eo_sandy1

October 31, 2012

 

Kilomanjaro’s Shrinking Ice Fields — For whatever reason, the Snows of Kilomanjaro are shrinking.

The EO site explains:

Despite Mount Kilimanjaro’s location in the tropics, the dry and cold air at the top of the mountain has sustained large quantities of ice for more than 10,000 years. At points, ice has completely surrounded the crater. Studies of ice core samples show that Kilimanjaro’s ice has persisted through multiple warm spells, droughts, and periods of abrupt climate change.

But trends beginning more than a century ago suggest Kilimanjaro’s peaks may soon be ice-free. Between 1912 and 2011, the mass of ice on the summit decreased by more than 85 percent. Researchers say it’s no longer a question of whether the ice will disappear but when. Estimates vary, but several scientists predict it will be gone by 2060.

Rising air temperatures due to global warming could be contributing to the ice loss, but a number of other factors are just as important, if not more so. An increasingly dry regional atmosphere, for example, is starving the mountain of the fresh snow needed to sustain the ice fields. Drier air is also reducing cloud cover and allowing more solar energy to warm the ice surfaces.

eo_kilomanjaro1

Northern Ice Field — Credit: Kimberly Casey, NASA

 

Ashfall from the Karymsky Volcano — It seems that there is always a volcano erupting somewhere in Kamchatka.

eo_karymsky

 

Bylot Island in Winter and Summer — Bylot Island is in the Canadian Arctic. The winter shot, with the sun very low in the sky, has elongated shadows which accent the topography.

eo_bylot_winter

eo_bylot_summer

Grace and Peace

December 10, 2012 Posted by | Geology, Imagery | 1 Comment

Thin ice and the importance of Quaternary geology

From NASA Earth Observatory:

2011 Sea Ice Minimum

From the description (emphasis added):

In September 2011, sea ice covering the Arctic Ocean declined to the second-lowest extent on record. Satellite data from NASA and the National Snow and Ice Data Center (NSIDC) showed that the summertime ice cover narrowly avoided a new record low.

[…]

Melt season in 2011 brought higher-than-average summer temperatures, but not the unusual weather conditions that contributed to the extreme melt of 2007, the record low. “Atmospheric and oceanic conditions were not as conducive to ice loss this year, but the melt still neared 2007 levels,” said Walt Meier of NSIDC. “This probably reflects loss of multi-year ice in the Beaufort and Chukchi seas, as well as other factors that are making the ice more vulnerable.”

The low sea ice level in 2011 fits the pattern of decline over the past three decades, said Joey Comiso of NASA’s Goddard Space Flight Center. Since 1979, September Arctic sea ice extent has declined by 12 percent per decade.

“The sea ice is not only declining; the pace of the decline is becoming more drastic,” he noted. “The older, thicker ice is declining faster than the rest, making for a more vulnerable perennial ice cover.”

While the sea ice extent did not dip below the record, the area did drop slightly lower than 2007 levels for about ten days in early September 2011. Sea ice “area” differs from “extent” in that it equals the actual surface area covered by ice, while extent includes any area where ice covers at least 15 percent of the ocean.

Arctic sea ice extent on September 9, 2011, was 4.33 million square kilometers (1.67 million square miles). Averaged over the month of September, ice extent was 4.61 million square kilometers (1.78 million square miles). This places 2011 as the second lowest ice extent for both the daily minimum and the monthly average. Ice extent was 2.43 million square kilometers (938,000 square miles) below the 1979 to 2000 average.

Climate models have suggested that the Arctic could lose almost all of its summer ice cover by 2100, but in recent years, ice extent has declined faster than the models predicted.

A few years back, I blogged about a report that the Arctic Ocean may have been ice-free around 6000-7000 years ago, so this may be a natural cycle. Or it may be caused by human-induced global warming. I don’t know. I ended that post with the following:

I’m not a global warming denier, which bothers some of my friends. I do believe that human activities are affecting Earth’s climate. This does point out, however, the importance of geological studies of Quaternary (ice age to present) climate systems. Whatever is happening today, even if caused by humans, can only be fully understood in its geological context.

Grace and Peace

October 7, 2011 Posted by | Climate Change, Creation Care, Environment, Imagery, Nature, Why Earth science matters | , , , | 8 Comments

Earth Observatory images

A few NASA Earth Observatory images from the past few months:

Mataiva Atoll, Tuamotu Archipelago, South Pacific Ocean, August 30, 2010

Credit: ISS Expedition 24 Crew

This image makes a great desktop background. The full-resolution image doesn’t have labels.


The Water Planet, October 2, 2010

Credit: NASA MODIS

Arthur C. Clarke once remarked, “How inappropriate to call this planet Earth when it is quite clearly Ocean.”


Susitna Glacier, Alaska, October 20, 2010

Credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

Note the complex ice deformation along much of the length of glacier. Most of the lower portion of the glacier is completely covered by debris.


Strong Extratropical Cyclone Over the US Midwest, October 29, 2010

Credit: NASA GOES Project Science Office

This low pressure system brought severe weather to much of the central U.S., and set a record low atmospheric pressure for a non-hurricane storm in the U.S.


Matusevich Glacier, Antarctica, November 7, 2010

Credit: NASA EO-1 team


Nile River Delta at Night, November 8, 2010

Credit: ISS Expedition 25 Crew


Grace and Peace

November 26, 2010 Posted by | Geology, Imagery, Meteorology | | Leave a comment

Earth Observatory goodies

Here are some more great images from NASA’s Earth Observatory:

Mid-November Colorado Snowstorm --- http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=41305&src=nha (Yippee! We got about 8 inches here in Lakewood; our fourth snowfall of the season already!)

Grace and Peace

November 19, 2009 Posted by | Geology, Imagery | Leave a comment

Earth Observatory — recent images

Some recent images from NASA’s Earth Observatory Image of the Day:

Ash and Steam Plume, Soufriere Hills Volcano, Montserrat

Ash and Steam Plume, Soufriere Hills Volcano, Montserrat --- 10/19/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40803

Marion Island, South Africa --- 10/18/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40806 --- Note the smaller cones on the flanks of this volcanic island

Marion Island, South Africa --- 10/18/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40806 --- Note the smaller cones on the flanks of this volcanic island in the Indian Ocean southeast of South Africa.

Oblique View of the Arnica Fire, Yellowstone National Park, Wyoming --- 10/12/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40681

Oblique View of the Arnica Fire, Yellowstone National Park, Wyoming --- 10/12/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40681

Rainfall from Typhoon Parma --- 10/10/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40687 --- The Philippines got hit three times by this one typhoon.

Rainfall from Typhoon Parma --- 10/10/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40687 --- The Philippines got hit three times by this one typhoon.

Glaciers Flow into a Greenland Valley --- 9/13/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40169

Glaciers Flow into a Greenland Valley --- 9/13/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40169

Black Point Lava Flow, Arizona --- 9/7/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40076

Black Point Lava Flow, Arizona --- 9/7/2009 --- http://earthobservatory.nasa.gov/IOTD/view.php?id=40076

Grace and Peace

October 21, 2009 Posted by | Geology, Imagery | , , | 2 Comments

Sarychev Peak eruption

From NASA’s Earth Observatory: Sarychev Peak Eruption, Kuril Islands, Russia.

Credit: NASA/International Space Station astronauts

Credit: NASA/International Space Station Expedition 20 crew

From the Earth Observatory description:

A fortuitous orbit of the International Space Station allowed the astronauts this striking view of Sarychev Volcano (Kuril Islands, northeast of Japan) in an early stage of eruption on June 12, 2009. […] Ash from the multi-day eruption has been detected 2,407 kilometers east-southeast and 926 kilometers west-northwest of the volcano, and commercial airline flights are being diverted away from the region to minimize the danger of engine failures from ash intake.

This detailed astronaut photograph is exciting to volcanologists because it captures several phenomena that occur during the earliest stages of an explosive volcanic eruption. The main column is one of a series of plumes that rose above Matua Island on June 12. The plume appears to be a combination of brown ash and white steam. The vigorously rising plume gives the steam a bubble-like appearance; the surrounding atmosphere has been shoved up by the shock wave of the eruption. The smooth white cloud on top may be water condensation that resulted from rapid rising and cooling of the air mass above the ash column. This cloud is probably a transient feature: the eruption plume is starting to punch through. The structure also indicates that little to no shearing wind was present at the time to disrupt the plume. […]

By contrast, a cloud of denser, gray ash—probably a pyroclastic flow—appears to be hugging the ground, descending from the volcano summit. The rising eruption plume casts a shadow to the northwest of the island (image top). Brown ash at a lower altitude of the atmosphere spreads out above the ground at image lower left. Low-level stratus clouds approach Matua Island from the east, wrapping around the lower slopes of the volcano. Only about 1.5 kilometers of the coastline of Matua Island (image lower center) are visible beneath the clouds and ash.

I’ve got this one set as my desktop background this week.

Grace and Peace

June 20, 2009 Posted by | Geology, Imagery, Natural Disasters | , | 1 Comment

Drought and recovery

These images from the NASA Earth Observatory show areas of drought (brown = below average plant growth) and excess plant growth (green = above average plant growth).

Northern Iraq is suffering a severe drought. Much of the country’s grain is dependent on seasonal rainfall rather than irrigation:

Credit: NASA/Terra/MODIS

Credit: NASA/Terra/MODIS

Grain-producing regions of Afghanistan, on the other hand, are recovering from a period of drought, with the wheat crop responding well to spring rains:

Credit: NASA/Terra/MODIS

Credit: NASA/Terra/MODIS

Satellite imagery like this gives governments and aid agencies a quick way to analyze conditions on the ground.

Iraq image: Earth Observatory — Drought in Iraq

Afghanistan image: Earth Observatory — Crop Recovery in Afghanistan

Grace and Peace

June 20, 2009 Posted by | Geography, Imagery | , , , | Leave a comment

Solar evaporation ponds, Chile

From NASA’s Earth Observatory: Solar Evaporation Ponds, Atacama Desert, Chile

SolarEvaporationPonds

Credit: NASA/ISS

Grace and Peace

June 13, 2009 Posted by | Imagery | 4 Comments

Aral Sea — environmental disaster

This is all that is left of what was the Earth’s fourth largest lake only 50 years ago.

From NASA’s Earth Observatory: Dust Over the Aral Sea.

Credit: NASA

Credit: NASA/Terra MODIS

In the 1960s, the Soviet Union started diverting most of the water from the rivers that fed the Aral Sea to irrigation, primarily for cotton. This led to an environmental catastrophe that continues to this day. Effects of this include:

  • Drying up of the lake, which is now only 10% of its former size.
  • Increasing salinity of the lake. Only the northernmost basin still has low enough salinity to support fish. Most native species are gone.
  • Creation of dust storms blowing off of the dry lake bed. In addition to salt, this dust contains pesticides and industrial wastes, which cause health problems for residents living downwind.
  • Widespread unemployment and other economic hardships.

(For an animation of the shrinking of the Aral Sea, go to http://en.wikipedia.org/wiki/File:Aral_Sea.gif)

Our actions as humans always have consequences. Some consequences can be predicted, others are unforeseen; some are small, and others are major. What will the consequences of our current activities be? What activities are we now involved in that will have long-term negative consequences in the future?

“A prudent man sees danger and takes refuge, but the simple keep going and suffer for it.” (Prov 22:3 NIV)

Grace and Peace

May 24, 2009 Posted by | Environment, Geology, Imagery | Leave a comment

Lake Eyre, Australia

I love this picture, as only a geologist who loves streams and sediments could.

From NASA’s Earth Observatory site: Rare Refill of Lake Eyre, Australia’s Simpson Desert.

LakeEyreAustralia

Credit: NASA/Landsat-5

From the EO description:

Waves in central Australia’s Simpson Desert usually come in the form of sand dunes. In these images, they ripple in long vertical lines across the surface of the desert. But occasionally, summer rain from northern Australia flows down into the desert, filling dry river channels and empty lake beds. Very occasionally, the water reaches a vast lake bed called Lake Eyre, turning it into a shallow inland sea where birds flock to breed.
In early 2009, heavy rains brought major flooding to nearly every river system in Queensland, Australia. By May, the water had made its way south and had started to fill Lake Eyre. The top image provides a natural-color view of water pouring into the lake through one of many channels that drain the desert during the rainy season. The muddy brown water spreads into the lake in a triangular alluvial fan.

Waves in central Australia’s Simpson Desert usually come in the form of sand dunes. In these images, they ripple in long vertical lines across the surface of the desert. But occasionally, summer rain from northern Australia flows down into the desert, filling dry river channels and empty lake beds. Very occasionally, the water reaches a vast lake bed called Lake Eyre, turning it into a shallow inland sea where birds flock to breed.

In early 2009, heavy rains brought major flooding to nearly every river system in Queensland, Australia. By May, the water had made its way south and had started to fill Lake Eyre. [This] image provides a natural-color view of water pouring into the lake through one of many channels that drain the desert during the rainy season. The muddy brown water spreads into the lake in a triangular alluvial fan.

Each depositional environment in this image will produce sediments with a distinct combination of grain size, sedimentary structures (various types of ripples and dunes, as well as things like mud cracks), mineralogy (evaporites in the lake basin), and trace fossils (footprints, burrows). The main depositional environments in this image are stream channel, alluvial fan/delta, arid lake, shoreline, and sand dune. Within each of these there are more specific depositional sites, such as near-shore or deeper water lake deposits. These are the types of things that enable geologists to interpret the depositional environments of ancient sedimentary rocks.

Grace and Peace

May 24, 2009 Posted by | Geology, Imagery | , , | 2 Comments

Lake Powell images, 1999 to 2009

NASA’s Earth Observatory has a series of images from 1999 to 2009 showing fluctuating water levels in Lake Powell in southeastern Utah. Lake Powell is formed by Glen Canyon Dam on the Colorado River in northern Arizona.

Credit:

Lake Powell 1999, Credit: NASA Landsat 5

Lake Powell 2008, Credit: NASA Landsat 5

Lake Powell 2008, Credit: NASA Landsat 5

Earth Observatory has a “play” link to watch the images in played in order.

From the description at the NASA Earth Observatory site:

The Colorado River flows from the Rocky Mountains in Colorado through the southwestern United States. Along its route, the river passes through an elaborate water-management system designed to tame the yearly floods from spring snowmelt and to provide a reliable supply of water for residents as far away as California. The system is both appreciated for the water it provides and criticized for the environmental and cultural losses it has created.

Among the dams on the Colorado is Glen Canyon Dam in Arizona, which creates Lake Powell—a deep, narrow, meandering reservoir—upstream in southern Utah. In the early twenty-first century, this modern marvel of engineering faced an ancient enemy: severe, prolonged drought in the American Southwest. Combined with water withdrawals that many believe are not sustainable, the drought has taken its toll on the water level in Lake Powell over the past decade.

Grace and Peace

May 15, 2009 Posted by | Environment, Geography, Geology, Imagery | , | Leave a comment

Santa Barbara fires

From NASA’s Earth Observatory: Jesusita Fire, California, near Santa Barbara, California, 5/8/2009.

Credit: NASA

Credit: NASA (Terra - MODIS)

The red outline areas indicate hotspots, and represent the areas of active wildfires.

Grace and Peace

May 11, 2009 Posted by | Environment, Geography, Imagery, Natural Disasters | | Leave a comment

NASA Earth Observatory turns 10 — vote for your favorites — final day of voting

Monday, April 27th is the last day to vote for your favorite image from NASA’s Earth Observatory.

Grace and Peace

April 26, 2009 Posted by | Environment, Geography, Geology, Imagery, Maps | | Leave a comment

NASA Earth Observatory turns 10 — vote for your favorites — final round

Out of over 3000 images that have appeared over the past ten years on the NASA Earth Observatory site, viewers have voted and narrowed it down to their favorite 50. From now until April 27th, viewers can vote for their favorite out of these 50, and the winning image will be announced on April 29th.

Go to Earth Observatory to vote. Here they are:

eofinals

eofinals2

eofinals3

Again, go to Earth Observatory to vote. Here’s my favorite:

Lena River Delta, Russia

Lena River Delta, Russia

Grace and Peace

April 14, 2009 Posted by | Environment, Geography, Geology, Imagery, Maps | | Leave a comment

LIDAR image of Mima mounds

Mima mounds are small hills (about 2 m tall, about 10 m across) of unknown origin that occur in groups of hundreds or thousands in Washington State and other places. The most famous group of these mounds are at Mima Prairie near Olympia, Washington. I haven’t been at this site, but I have been at a smaller group of Mima mounds in the Channeled Scablands of Eastern Washington.

The Washington Department of Natural Resources has released incredibly detailed topographic models of Mima Prairie:

Credit: Washington DNR via The Seattle Times

Credit: Washington DNR via The Seattle Times

This image was created using LIDAR, which is sort of like RADAR, except it uses laser light rather than radio waves. LIDAR can see through vegetation (if you want it to; it depends on how you set it up and process the data) and can produce an image with accuracies of less than ten centimeters.

The origin of Mima mounds is uncertain. Common explanations include glacial or periglacial (i.e. near-glacier) processes, gophers, earthquakes, and Indian burial mounds.

HT: The Seattle Times (via my sister)

Wikipedia: Mima mounds

Grace and Peace

P.S. The U.S. Forest Service has a good overview of the use of LIDAR for natural resource investigations. The following image shows not only the ground surface, but the forest canopy:

Credit: USFS/RSAC

Credit: USFS/RSAC

April 3, 2009 Posted by | Geology, Imagery, Maps | Leave a comment

NASA Earth Observatory turns 10 — vote for your favorites

The NASA Earth Observatory is ten years old (this is where I get many of the images I show on The GeoChristian). For most of that time, EO has featured a new image every day, for a total of over 3,000 fantastic images of the Earth (mostly).

EO is asking for its viewers to vote for their favorite images:

Vote for Your Favorite Image of the Day
In celebration of our anniversary, we want to hear which Images of the Day have impressed you most over the past ten years. Tell us what you have found most beautiful, most fascinating, or most unusual by voting for your favorites. Voting will be in two rounds:

  • In Round 1 (March 31-April 13), you can vote for images from the entire Image of the Day catalog. We know it can be hard to pick just one, so each user can choose up to 10 favorite images per day. Each day, you can come back and cast ten more votes—either for the same images you picked before, or a totally new set of ten.
  • In Round 2 (April 14-27), you can select your number one favorite Image of the Day from the top vote getters from Round 1.

On April 29, we will announce our readers’ 10 Favorite Images of the Day!

It was fairly easy to pick about thirty favorite images, but it was difficult to narrow it down to my top ten. Here are my ten picks, in no particular order:


Ocean Sand, Bahamas — 9/13/2002

x

Bands of sand and seaweeds in shallow water in the Bahamas.


Mount Vesuvius, Italy — 12/28/2000

x

Mount Vesuvius is surrounded by densely populated areas (blue).


Continue reading

April 1, 2009 Posted by | Environment, Geology, Imagery, Maps | | Leave a comment

Snow — finally

Denver has had a warm, dry winter. This past week, we finally got our first good snowfall of the year (up to 17 inches or 43 cm). Most of the snow came on Thursday, with sub-zero wind chill factors. Friday was bright and sunny, and NASA’s Terra satellite was kind enough to take this picture of the Denver area:

Credit: NASA/

Credit: NASA/Terra/MODIS

If the resolution were a lot better, you would be able to see the Nelstead family sledding, cross-country skiing, building a snow thing (can’t really call it a snow man), and having a snow ball fight.

I love snow.

Image from NASA’s Earth Observatory.

Grace and Peace

March 30, 2009 Posted by | Imagery | 1 Comment

Eruption of underwater volcano, Tonga

Here’s a video of an eruption of an underwater volcano near the South Pacific island of Tonga on March 19, 2009:

News articles:

London Times: Underwater volcano sends huge columns of ash into Pacific sky

Honolulu Advertiser: 7.9 quake off Tonga could intensify volcano’s eruption

From NASA’s Earth Observatory: Submarine Eruption in the Tonga Islands:

Credit: NASA

Credit: NASA

Grace and Peace

March 20, 2009 Posted by | Geology, Imagery, Natural Disasters | , | Leave a comment