New Study Shows That as the Climate Warms, Melting of Alaskan Glaciers is Adding Significantly to Sea Level Rise

By Tom Yulsman | June 17, 2015 5:02 pm
Alaskan glaciers

An animation of Landsat satellite images showing dramatic shrinkage of the Columbia Glacier in Alaska. The animation pauses for extra time on the first image, acquired in 1986, and the last one from 2914. (Images: NASA Earth Observatory. Animation: Tom Yulsman)

As heat about global warming continues to emanate from the presidential campaign trail, new research published today shows that the melting of Alaskan glaciers is largely the result of a warming climate.

According to the study, accepted for publication in the peer-reviewed Geophysical Research Letters, Alaskan glaciers lost about 1.4 trillion tons of ice between 1994 and 2013. That works out to about 75 billion tons a year.

Given that rate of ice loss, we’re talking about enough water to cover the entire state of Alaska to a depth of one foot every seven years.

The melting is unlikely to stop any time soon.

SEE ALSO: As Republicans Criticize Pope’s Stance on Climate Change, NASA’s Monthly Update Shows Earth Continuing to Heat Up

I created the animation above using Landsat remote sensing imagery to help portray just how significant the melting of Alaskan glaciers has been. You’re looking at changes to the Columbia Glacier between 1986 and 2014. The glacier flows down the flanks of the Chugach Mountains and into an inlet that leads into Prince William Sound, about 90 miles west of Anchorage. (For a Google map locating the glacier, click here.)

As the animation shows, it has been shrinking dramatically. In fact, it is one of the most rapidly changing glaciers in the world. Since 1980, the glacier’s terminus has retreated more than 12 miles to the north, it has thinned by about 1,500 vertical feet, and has lost about half of its total volume. Read More

As Republicans Criticize Pope’s Stance On Climate Change, NASA’s Monthly Update Shows Earth Continuing to Heat Up

By Tom Yulsman | June 16, 2015 9:48 pm

NASA’s map of how temperatures departed from the long-term mean during May 2015. Warm anomalies are depicted in yellow, orange and red tones. Cool anomalies in blue and purple. (Source: NASA Goddard Institute for Space Studies)

NASA’s monthly update on Earth’s average temperature is out, and it shows this past May in a tie with May 2012 for second warmest on record for the month.

Only May of last year was warmer in NASA’s record, which extends back to 1881.

So far, 2015 overall has been very warm. And with El Niño strengthening in the Pacific, it’s looking increasingly likely that this year will finish as the warmest on record, surpassing year. But time will tell.


Twelve month running mean of global average temperature. (Source: NASA)

Of course, one month and one even one year do not a trend make. So click on the thumbnail at right for the long term trend of global average temperature, as determined by NASA.

And if you have believed the political hype that there has been no global warming for a decade or so, please consider the latest scientific evidence to the contrary: a recent peer-reviewed study showing that the rate of global warming during the first 15 years of the 21st century has been at least as great as the last half of the 20th century. (For a story explaining the research, check out Chris Mooney’s piece at the Washington Post: “Federal scientists say there never was any global warming ‘pause.'”) Read More

El Wimpo Transforms Into an El Niño That’s Showing Increasing Signs of Becoming a Humdinger

By Tom Yulsman | June 10, 2015 7:12 pm

The evolution of sea level height anomalies from early January through late May, as measured by the Jason-2 satellite. The tongue of red, orange and white colors stretching along the equator shows areas where sea level is above average due to anomalous warm ocean waters — a hallmark of El Niño. (Source: NASA Jet Propulsion Laboratory)

|UPDATE: Since I posted this story yesterday, the U.S. Climate Prediction Center has released it’s monthly diagnostic discussion of the ongoing El Niño, concluding that it is strengthening and will very likely continue into Northern Hemisphere winter. Please see below for the details. |

Once regarded as indicative of an “El Wimpo”, conditions in the Pacific Ocean are pointing to a stronger and stronger El Niño.

The latest evidence that El Niño conditions are strengthening comes from the Australian Bureau of Meteorology. In a report released this week, the agency noted that abnormally warm surface waters have spread significantly in the tropical Pacific over the past two weeks — a hallmark of El Niño. As the report puts it:

It is unusual to have such a broad extent of warmth across the tropical Pacific; this has not been seen since the El Niño event of 1997-98.

That El Niño was a humdinger. Here’s how a report from the National Climatic Data Center described that event:

The winter of 1997-1998 was marked by a record breaking El Nino event and unusual extremes in parts of the country. Overall, the winter (December 1997- February 1998) was the second warmest and seventh wettest since 1895. Severe weather events included flooding in the southeast, an ice storm in the northeast, flooding in California, and tornadoes in Florida.

We’ll just have to wait to see whether the current El Niño follows a similar pattern. Suffice it to say that the Australian Bureau of Meteorology isn’t alone in seeing a strengthening of this year’s El Niño.

|Update 6/11/15: According to the diagnostic discussion released by the U.S. Climate Prediction Center today, there is a greater than 90 percent chance that El Niño will continue through the Northern Hemisphere fall this year, and about an 85 percent chance that it will last through the 2015-16 winter. “Collectively, these atmospheric and oceanic features reflect an ongoing and strengthening El Niño.”

The CPC also notes that “the consensus of forecasters slightly favors a strong event . . . . relative to a weaker event.” The agency cautions that making strength projections at this point is the most challenging aspect of El Niño forecasting. So this El Niño could ultimately wind up being moderate or weak, and it could even dissipate  completely — “though at increasingly lesser odds,” the CPC notes. |

The Japan Meteorological Agency concurs that El Niño is strengthening. Sea surface temperatures “were remarkably above normal from west of the date line to the South American coast over the equatorial Pacific in May,” the agency’s report noted. Temperatures beneath the ocean surface were also “remarkably above normal” in the central and eastern tropical Pacific, which will help sustain the El Niño episode into the Northern Hemisphere winter.

To get a visual sense of how El Niño has evolved since the start of the year, make sure to check out the animation at the top of this post. I created it using images from the Jason-2 satellite. These images show sea level anomalies, places where sea level is higher or lower than average.

High sea level, depicted in reds, oranges and white, has expanded along the equator to the west of South America. This has occurred as warmer sea temperatures have caused ocean waters to expand.

Here’s another animation, this one showing the evolution of sea surface temperatures. Read More

For the Lower 48 States of the U.S., May Was the Wettest of 1,452 Months on Record

By Tom Yulsman | June 8, 2015 11:27 pm



Most of us probably know that May was astonishingly wet in much of the country. But now, thanks to a report just released by the National Centers for Environmental Information (formerly the National Climatic Data Center), we know just profoundly soggy it was.

For the contiguous states, not only was it the wettest May on record, but in 121-years of record-keeping it was also the wettest month ever.

To put it another way, this past May was wetter than all 1,451 months preceding it.

All that cloudiness and moisture helped hold temperatures down during the month. The average temperature for the contiguous United States was near the median value for the 121-year record. But there were exceptions to this moderate picture — most dramatically in Alaska, which experienced its warmest May, with an average temperature that was a shocking 7.1 degrees F above the long-term average.

Also, as moderate as the U.S. average temperature might have been in May, the weather overall has been anything but. According to the report, the U.S. Climate Extremes Index for the year to date has been 30 percent above average, with the contiguous United States experiencing its 19th highest value on record. This was largely due to extremes in warm maximum and minimum temperatures, as well as the number of days with precipitation. Read More

CATEGORIZED UNDER: Climate, select, Top Posts, Weather

eARTh Abstraction: Breakup of Arctic Sea

By Tom Yulsman | June 8, 2015 1:37 pm

Breakup of Arctic sea ice in the Denmark Strait between Greenland and Iceland, as seen through the clouds from a commercial airliner on June 3, 2015. (Photo: ©Tom Yulsman)

If you have followed this blog with any regularity you may have noticed that I haven’t posted anything for awhile. I was on vacation in Europe and decided to take a break from blogging while I was gone.

Now that I’m back, I thought I’d share some iPhone photographs of Arctic sea ice I shot while on the way back from Poland to Denver, via Frankfurt. There’s a bit of a news peg, since the extent of Arctic sea ice in May was the third lowest in the satellite record, which extends back to 1978. As the National Snow and Ice Data Center put it recently:

Melt season is underway, and sea ice in the Arctic is retreating rapidly. At the end of May, ice extent was at daily record low levels.

And this:

Now that we are entering the month of June, the rate of ice loss is likely to quicken, but how fast will depend on the weather conditions and the date of ice surface melt onset across the high Arctic.

Hoping to get some photos of the seasonal sea ice breakup during my Lufthansa flight back from Europe, I parked myself by a door in the back of the 747-400 and gazed out the window and hoped the clouds would part.

They finally did as we cruised 34,000 feet above the Denmark Strait. The photo above is the first one I shot. Read More

Stunning Images of Mars Reveal Vistas That Are Eerily Reminiscent of Landscapes Here on Earth

By Tom Yulsman | May 11, 2015 12:27 pm

The view from Mount Sharp on Mars, as seen by the Curiosity rover on April 10, 2015. (Source: NASA/JPL-Caltech/MSSS)

The redrock canyons and up-tilted strata of eastern Utah form some of my favorite landscapes on Earth. So when I saw the scene visible in the image above it really stopped me dead in my tracks.

Source: NASA/JPL-Caltech/Univ. of Arizona

Source: NASA/JPL-Caltech/Univ. of Arizona

Luckily, it didn’t do the same for the Curiosity rover on Mars, which has been slowly climbing the Red Planet’s Mount Sharp and sent this spectacular view of the surrounding landscape back to Earth in early April. What really strikes me about this image, and the ones to follow, is just how familiar it looks.

The jagged skyline in the distance is part of the higher elevations of Mount Sharp. For a map showing the rover’s route through this landscape, click on the thumbnail at right. (And for an explanation of the notations on the map, click here.)

The image at the top of this post is actually a relatively small crop from a sweeping panorama that combines 33 telephoto images into one Martian vista. Here’s the entire panorama: Read More

WATCH: Landfall of Super Typhoon Noul. Plus: Ana Becomes Strongest Tropical Storm to Hit U.S. This Early in the Year

By Tom Yulsman | May 10, 2015 11:55 am

Typhoon Noul made landfall in the Philippines on May 10, 2015, as seen by the MTSAT satellite. (Source: Japan Meteorological Agency)

Super Typhoon Noul roared ashore on the extreme northeastern corner of the island of Luzon in the Philippines at about 4:45 p.m. local time on Sunday (4:45 EDT).

Click on the screenshot above to watch an animation of MTSAT images showing the storm approach and make landfall before curving toward the northeast and heading back out to sea. In the animation, make sure to check out that dark, clearly defined eye.

And for an astounding closeup view, click here to watch an animation of imagery from the Himawari-8 satellite, courtesy of the Cooperative Institute for Meteorological Satellite Studies. The detail visible inside the eye is simply mind boggling. (The resolution is 0.5 kilometers, which means the animation will take awhile to load unless you have a very fast Internet connection.)

Noul’s exact strength at landfall seems to be in dispute. The Joint Typhoon Warning Center reports that the storm came ashore with sustained winds of 150 miles per hour (130 knots), and gusts to 184 mph (160 knots). But the Philippine Atmospheric, Geophysical and Astronomical Services Administration is reported to have pegged Noul’s sustained winds at 115 mph with gusts to 136.

Either way, Noul prompted 2,500 people in the thinly population region to huddle in shelters while the worst of the storm passed. I haven’t seen any reports of damage and casualties yet.

SEE ALSO Ana and Noul: A Tale of Two Cyclones Read More

Ana and Noul: A Tale of Two Cyclones

By Tom Yulsman | May 9, 2015 4:33 pm

Astronaut Scott Kelly shot this photo of Tropical Storm Ana from the International Space Station on Thursday, May 8, 2015.

Tropical Storm Ana is headed for landfall in the Carolinas early on Sunday morning. You can see the cyclone swirling near the coast in the image above shot from the International Space Station.

Ana is a preemie: She has arrived three weeks before the official start of the Atlantic hurricane system. And as a preemie, Ana is not terribly strong: As I’m writing this at about 5:30 p.m. EDT on Saturday, maximum sustained winds are pegged at 60 miles per hour.

The storm is now moving off the sustaining warmth of the Gulf Stream and is beginning to encounter cooler waters. That combined with wind shear and dry air is forecast to cause gradual weakening until the storm makes landfall. Read More

Snowpack in the West “isn’t just low — it’s gone”

By Tom Yulsman | May 9, 2015 3:16 pm

An animation of images acquired by NASA’s Terra satellite, one on April 27, 2013, and the other from April 29 of this year, when snowpack was less extensive. (Source: NASA Worldview)

The quotation in the headline for this post is the assessment of David Garen, a hydrologist with the Natural Resources Conservation Service. It’s a slight exaggeration, as the animation above shows. But not by much.

As Garen puts it in a press release issued yesterday by his agency:

Across most of the West, snowpack isn’t just low – it’s gone. With some exceptions, this year’s snowmelt streamflow has already occurred . . .  We still have some snowpack in northern Colorado, western Montana and southern Wyoming. In addition, snowmelt from Canada will flow into the Columbia River


Source: NCDC

Snowpack at many monitoring stations is at or near the lowest on record, according to Garen. The culprit: strikingly warm temperatures in the West that hindered accumulation in the mountains and then led to premature and rapid melting.

Click on the thumbnail at right to see a map showing how statewide maximum temperatures varied from the long term average between January 1 of this year and the end of April.

And please make sure to keep reading for a discussion of the broader context of what’s happening to snowpack in the West. That includes megadroughts of the past — and how they may serve as an analogue for what we might expect in the future, particularly as the climate continues to warm under our influence.

SEE ALSO: Watch the West’s Snowpack Shrink Dramatically Right Before Your Eyes in Striking Satellite Image Animations

But before I get to that, here are some additional details about this year’s thin western snowpack — and the impacts we should expect. Read More

Double Typhoon Trouble in the Western Pacific, Plus a Brewing Storm in the Atlantic Ocean

By Tom Yulsman | May 6, 2015 5:25 pm

Two tropical systems are seen in this satellite image of the Pacific Ocean basin. Typhoon Noul is marked TY06W. The system to its east stands a high chance of developing into a typhoon. (Source: JTWC)

As Typhoon Noul continues to spin up in the western Pacific Ocean, posing a distinct threat to the Philippines this weekend, a big tropical depression to the east is growing and stands a high chance of developing into a “significant tropical cyclone within the next 24 hours,” according to the Joint Typhoon Warning Center.

Meanwhile, in the Atlantic, an area of disturbed weather over the Northwest Bahamas designated as Invest 90L could become a subtropical depression by Friday. The storm will likely bring heavy rain and high surf to the Carolinas on Friday.

Back in the Pacific, Noul has already brought high winds and heavy rain to Yap Island. The typhoon’s maximum sustained winds were pegged earlier today at 86 miles per hour, with gusts to 103. Here’s how the typhoon looked in satellite microwave imagery as it approached Yap: Read More



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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