My pick for the most compelling — and scary — remote sensing image of 2018

By Tom Yulsman | December 29, 2018 6:23 pm
The top remote sensing image of 2018

An image of California’s Camp Fire, created using natural color and infra-red data acquired by the Landsat-8 satellite on Nov. 8, 2018. (Image courtesy Pierre Markuse)

This past year brought all too many disasters, including rampaging wildfires, destructive volcanic eruptions, swirling tropical cyclones, and a host of other events that brought misery to millions of people worldwide.

Many were visualized by satellites looking down on Earth, and as 2018 draws to a close, I thought I’d feature one that I found to be particularly compelling. It’s the image above showing California’s Camp Fire, created by blogger and remote sensing expert Pierre Markuse. It’s my personal pick for top remote sensing image of 2018.

The Camp Fire ignited on Nov. 8, 2018 and quickly exploded, engulfing and ultimately destroying the town of Paradise, California. As of Dec. 19, the death toll stood at 86 people, which makes it the seventh deadliest wildfire in U.S. history, and the 14th deadliest worldwide. (Jeff Masters of the Category 6 blog tallied the statistics here. But keep in mind that since he wrote his story, the death toll of the Camp Fire was actually reduced.)

Ultimately engulfing 153,336 acres — about half the size of the City of Los Angeles — the Camp Fire was also the most destructive wildfire in California history, incinerating 14,500 residential and commercial buildings.

Markuse created the image using data from the Landsat-8 satellite. I find it particularly noteworthy for a number of reasons. First, you can see the town of Chico, population 93,293, toward the left, partly obscured by the huge smoke plume. This provides a sense of scale. Read More

This started as a story about really cool clouds on Earth, but then it led to this: Does it snow on Mars?

By Tom Yulsman | December 29, 2018 4:44 pm
Snow falling from clouds near Boulder, Colorado on Dec. 19, 2018 did not reach the ground — a classic example of virga. That got me to thinking: Does it snow on Mars?

Snow falling from clouds near Boulder, Colorado on Dec. 19, 2018 did not reach the ground — a classic example of virga. (Photo: ©Tom Yulsman)

Mars is certainly cold. With temperatures that can plunge to more than negative 100 degrees Celsius, it’s bloody frigid!

But as cold as it might get, does it snow on Mars?

This wasn’t the first thing that came to mind when I photographed the scene above near Boulder, Colorado with my iPhone. But when I got home and started investigating the beautiful phenomenon I had documented, I eventually came around to that rather un-obvious question. How I came to it — as well as the answer — is a bit of an interesting journey, so I hope you’ll keep reading.

First, what about those clouds in the image above? If you live somewhere with wide open vistas, you’ve probably seen the phenomenon yourself: darkish streaks appearing to hang from a cloud deck.

This is called “virga” —  precipitation falling from the clouds but mostly not reaching the ground. I’ve seen virga many times before, but usually in summer. This is when temperatures are high and humidity near the surface can be relatively low, causing shafts of rain falling from clouds to evaporate before the drops reach the ground.

But I shot the photo above on December 19th, two days before the winter solstice and well into meteorological winter. At the elevation of the cloud deck, temperatures were almost certainly well below freezing. So the virga probably consisted of little ice crystals. As they fell toward the ground, they simply sublimated — meaning they went from the frozen state to water vapor without first condensing into liquid.

I decided to write a post about it here at ImaGeo, and as I did my research, my mind wandered far from Colorado. All the way to Mars, which I knew had its own clouds.

I began wondering whether Martian clouds feature ice crystals streaming downward to form virga. Do ice crystals actually reach the ground as snow? And what might all of this look like from the surface? Read More

Seen from space: the volcanic eruption that likely triggered Indonesia’s devastating tsunami

By Tom Yulsman | December 24, 2018 2:52 pm
Krakatau volcanic eruption

A volcanic cloud from the eruption of Anak Krakatau in Indonesia on December 22, 2018 is seen in this animation of satellite images acquired by the Himawari-8 satellite. Two distinct volcanic pulses are evident. (After clicking on the screenshot above, click “play” in the upper left corner of the page that launches. If the animation does not run, refresh the page. Source: RAMMB/CIRA SLIDER)

In Indonesia, they call it “Anak Krakatoa, meaning “child of Krakatoa.”

It’s a volcano that rose from the sea in the 1920s decades after one of the most deadly volcanic cataclysms in recorded history killed tens of thousands of people and all but obliterated the island of Krakatoa, between Java and Sumatra.

Now, Anak Krakatau has itself brought great misery to Indonesia, with an eruption that apparently triggered an underwater landslide, which in turn sent a tsunami racing toward the western tip of the island of Java. A wall of water roared ashore, catching residents and vacationers completely unawares. As I’m writing this on Christmas Eve, more than 370 people have perished, and more than a hundred still are missing.

When Anak Krakatau erupted on December 22, Japan’s Himawari-8 weather satellite was watching from geostationary orbit, 22,239 miles overhead. Click on the screenshot above to watch what the satellite saw.

The animation consists of “GeoColor” imagery acquired in different parts of the electromagnetic spectrum at 10-minute intervals starting at 11:00 UTC. A first pulse of ash is visible at about 13:40, and then a second one at 15:20. As the animation continues, dawn breaks and a plume of ash and steam can still be seen amidst a cloudy atmosphere.

Here’s what the eruption looked like in the infrared part of the electromagnetic spectrum: Read More

In the Blink of an Eye, We’re Turning Back the Climatic Clock by 50 Million Years

By Tom Yulsman | December 14, 2018 3:45 pm
This animation based on computer modeling shows what climatic conditions will look like out to the year 2280 if we emissions of greenhouse gases are not restrained. The color coding shows how future conditions would compare to climates of the past. (Source: "Pliocene and Eocene provide best analogs for near-future climates," K. D. Burke et al, Proceedings of the National Academy of Sciences Dec 2018, 201809600; DOI: 10.1073/pnas.1809600115)

This animation depicts climatic conditions out to 2280 assuming emissions of greenhouse gases are not restrained. The color coding shows how future conditions would compare to past climates, with lighter orange corresponding to the Pliocene Epoch about 3 million years ago, and darker orange to the Eocene about 50 million years ago. Dark red indicates future climatic conditions with no past analog. (Source: “Pliocene and Eocene provide best analogs for near-future climates,” K. D. Burke et al, Proceedings of the National Academy of Sciences Dec 2018, 2018)

Absent serious action on climate change, we’ll continue careening toward a climatic cliff. And modern civilization will be hard-pressed to survive the plunge.

This is the essential take-away from new research probing Earth’s climatic past to yield insights into our future. The research finds that if our emissions of carbon dioxide and other greenhouse gases continue unabated, Earth’s climate will warm by the year 2150 to levels not seen since the largely ice-free Eocene Epoch about 50 million years ago.

That may seem like a long time on a human timescale. But consider that the research shows we’re currently on course to reversing 50 million years of cooling in just a couple of centuries. That may be so rapid that it will outpace our ability to adapt our agricultural and other modern life support systems.

Thanks to our emissions of greenhouse gases, “the Earth system is well along on a trajectory to a climate state different from any experienced in our history of agricultural civilizations,” write Kevin Burke and his co-authors in a paper published in the Proceedings of the National Academy of Sciences.

Here’s why that’s troubling: Modern human civilizations, made possible by agriculture, have thrived in what scientists term “a safe operating space,” meaning a stable, relatively benign climate. But now, staying within that safe space seems to be “increasingly unlikely,” the researchers write.

“If we think about the future in terms of the past, where we are going is uncharted territory for human society,” says the study’s lead author, Kevin Burke, in a press release. Burke led the research while he was a graduate student in the lab of paleoecologist John “Jack” Williams of the University of Wisconsin-Madison.

“We are moving toward very dramatic changes over an extremely rapid time frame, reversing a planetary cooling trend in a matter of centuries,” Burke says. Read More

Here’s what you may not have heard about the massive new report on climate change in the U.S.

By Tom Yulsman | November 25, 2018 8:18 pm

Many news outlets all but ignored a crucial part: the urgent need to adapt to changes already underway and in the pipeline

Climate change report emphasizes adaptation, but news media ignore it.

Research shows that wildfires in the western United States are already burning hotter, wider, and more frequently, thanks in large measure to human-caused climate change. Shown here is the 2018 Howe Ridge Fire in Glacier National Park. (Source: National Park Service, Glacier National Park)

The White House released a massive scientific report on climate change the day after Thanksgiving. Given that timing, you may have missed it entirely (which is probably what they had in mind).

But if you did manage to hear about it in news coverage, you may well have gotten the impression that the 1,656-page assessment, produced by 13 federal agencies, was devoted exclusively to the dire future we’ll continue hurtling toward unless we reduce emissions of heat-trapping carbon dioxide and other greenhouse gases.

That impression would be understandable, given that many news media outlets, including the New York Times, chose to frame their coverage almost entirely around predictions of crop failures, deteriorating infrastructure, thousands of deaths from heat waves — and a worst-case hit to the economy of 10 percent of the nation’s GDP by century’s end.

Largely left out of much of the coverage that I’ve seen is an equally important part of the Congressionally mandated report: the pressing need to adapt to changes that are already occurring, and inevitable future changes.

The federal report, prepared under the auspices of the U.S. Global Change Research Program, mentions the words “adapt” or “adaptation” at least 40 times, and “resilience” or “resilient” another 39 times. But the word “adapt” appears just once in the main New York Times story about the report; “resilience” or “resilient” not at all. And many other news outlets seems to have followed the lead of the Times.

Make no mistake about it: This second volume of the climate assessment, focusing on impacts, risks, and adaptation to climate change in the United States, does emphasize that global action is needed to reduce emissions of carbon dioxide and other greenhouse gases. But this mitigation of greenhouse gases, or GHGs, is just one part of the needed response, according to the report: Read More

Baby, it’s cold outside — but global warming has not taken a Thanksgiving break

By Tom Yulsman | November 22, 2018 11:07 am

President Trump falsely uses frigid weather to cast doubt on human-caused warming

An Arctic blast may have brought cold Thanksgiving temperatures to parts of the U.S., but the long-term trend of global warming continues

This global anomaly map compares temperatures in October 2018 to the 1951 to 1980 base period. (Source: NASA GISTEMP)

It sure is cold outside — at least in the northeastern United States. In fact, some portions of the region could experience their coldest Thanksgiving on record.

Blame it on an Arctic blast that is sending temps plummeting to levels normally associated with the dead of winter, not turkey day.

It’s called weather, not climate — a distinction that the President of the United States either doesn’t care about, or doesn’t understand (or perhaps both?): Read More

Three days in the life of Earth as seen by GOES-17, soon slated to be our latest operational weather satellite

By Tom Yulsman | November 18, 2018 6:53 pm
An animation of GOES-17 satellite images shows the full disk of our planet over three days between Nov. 19 and 22, 2018. (Source: RAMMB/CIRA Slider)

An animation of GOES-17 satellite images. (Source: CIRA/RAMMB/SLIDER)

The newest U.S. weather satellite has moved into its operational position over the Pacific Ocean and is sending back stunning imagery despite a problem with its primary instrument.

You can get a taste of that imagery in the animation above, showing the full disk of our planet over three days between Nov. 19 and 22, 2018. Click the image, and then make sure to zoom in and explore.

Here’s another example of beautiful imagery from the satellite, designated GOES-17:

GOES-17 was launched on March 1, 2018, and in the ensuing months it has been undergoing post-launch checkout and testing. After a three-week drift starting on October 24, The spacecraft arrived at its current position on Nov. 13. More testing is to come before it is scheduled to become officially operational as NOAA’s GOES West satellite on December 10, 2018.

Read More

Discovered under Greenland ice: a massive meteor impact crater the size of New York City

By Tom Yulsman | November 16, 2018 3:16 pm
Meteor impact in Greenland gouges out huge crater

An international team of scientists has discovered a massive meteor crater under a glacier at the edge of the Greenland ice sheet. This artist’s rendition shows what the meteor impact might have looked like. (Source: NASA’s Goddard Space Flight Center/Jefferson Beck)

A very curious feature has long been visible in satellite images of Greenland’s massive ice sheet, but until now, no one really knew for sure what formed it.

Greenland meteor impact crater

The edge of the Greenland Ice Sheet includes the semi-circular feature seen in this image acquired by NASA’s Aqua satellite on July 17, 2918. Beneath it is a newly discovered meteor impact crater. (Source: NASA Worldview)

You can see the feature for yourself in the satellite image at right — look for the conspicuously semi-circular edge to the ice sheet.

As it turns out, that semi-circular shape hints at what’s below a layer of ice more than a half mile thick: a massive impact crater that has been hiding in plain site.

Research shows that it was gouged out of Greenland’s bedrock by a large iron meteorite more than a half mile wide. The object crashed to Earth less than 3 million years ago and possibly as recently as 13,000 years ago. The resulting bedrock basin subsequently was covered by ice. And today, the edge of that ice traces the edge of the crater down below. Read More

MORE ABOUT: geology

Stunning satellite images and animations offer a sobering perspective on California’s raging infernos

By Tom Yulsman | November 10, 2018 2:17 pm
The raging Camp Fire inferno in Northern California

Data from the Landsat 8 satellite were used to create this image of the Camp Fire in Northern California on November 8, 2018, around 10:45 a.m. local time. (Source: NASA Earth Observatory)

In all the many years that I’ve covered wildfire, I don’t believe I’ve encountered anything like what we’ve seen with the Camp Fire blazing in California’s northern Sierra Nevada mountains. What really shocked me was the speed with which this cataclysmic inferno progressed to become what appears to be the most destructive in state history.

In a flash, an estimated 6,713 structures  were destroyed in the town of Paradise. “It’s phenomenal how fast the fire spread,” said Scott McLean, the deputy chief of the California Department of Forestry and Fire Protection, quoted in the N.Y. Times.

The Landsat 8 satellite image above offers an incredible view of the inferno. It was created using Landsat bands 4-3-2 — visible light — along with shortwave-infrared light to highlight active portions of the fire.

The Camp Fire started around 6:30 a.m. Pacific Standard Time, and by 8:00 p.m., it had already burned 20,000 acres. As I’m writing this on the morning of Saturday, Nov. 10, the fire has consumed 100,000 acres — half the size of New York City — and is about 20 percent contained, according to the latest update from CalFire. (Access the latest CalFire info on the fire here.)

To the south, the Woolsey and Hill fires are burning just west of Los Angeles. They’ve so far consumed about 75,000 acres.  You can see smoke from these blazes, as well as the Camp Fire, in this video:

Smoke from the Woolsey and Hill blazes is visible toward the bottom of the frame. The Camp Fire is toward the top.  Read More

Astronauts spy coffin-shaped object bigger than Manhattan slouching toward a “graveyard” north of Antarctica

By Tom Yulsman | October 31, 2018 3:23 pm

Source: NASA Earth Observatory.

Seriously, this gargantuan coffin-like object really was photographed by an astronaut aboard the International Space Station on September 23, 2018.

If you guessed that it is an iceberg, you are right.


A broader view of B-15T, from NASA’s Terra Satellite. (Source: NASA Earth Observatory)

Known rather unimaginatively as B-15T, the spooky, Brobdingnagian berg is seen here adrift in the South Atlantic Ocean between South Georgia and the South Sandwich Islands. NASA’s Earth Observatory published the photograph today as its image of the day.

And the day is, of course, Halloween.

Read More

CATEGORIZED UNDER: Antarctic, Miscellaneous, select, Top Posts


ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

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