Glory Versus the Curse of the Black Carbon

Kick back, make yourself some popcorn, and enjoy one of the latest offerings from NASA Television: a tongue-in-cheek trailer about the horrors of airborne particles called aerosols. Black carbon plays the villain, and it’s this sooty particle (which comes from wildfires, campfires, various industrial processes, and diesel fumes) that gets the blame for “cursing” atmospheric scientists with a “scourge of ignorance”.

Plenty of specialists here at Goddard Space Flight Center will tell you that, over the years, we’re making real progress understanding aerosols, but there’s little doubt that the tiny airborne droplets and particles have given climatologists headaches over the years.

Back in March of 2009, James Hansen, director of the Goddard Institute for Space Studies, laid out the key obstacles underpinning what he called the “Nasty Aerosol Problem” in a presentation he gave in Copenhagen. As he puts it in one slide: 

* “We do not have measurements of aerosols going back to the 1800s – we don’t even have global measurements today.

* Any measurements that exist incorporate both forcing and feedback.

* Aerosol effects on clouds are very uncertain.”

    NASA’s upcoming Glory mission, which carries a promising new gizmo for studying aerosols called the Aerosol Polarimetery Sensor (APS), looks to be our next best shot for getting a better handle on the problematic particles. Glory is hardly the only NASA effort addressing aerosols, but I’ve certainly noticed that nothing rivals a satellite mission (as opposed to, say, ground or aircraft campaigns) when it comes to generating buzz in the hallways.

    You can learn more about Glory here, here, and here. And why not follow Glory on Twitter or Facebook?

    –Adam Voiland, NASA’s Earth Science News Team

    Hungry? Try a Honeypot Ant…

    If I’ve learned anything as a science writer, it’s that scientists produce such a flood of fantastically odd factoids that boredom isn’t much of an occupational hazard. Heck, the chances that deep boredom will strike during work are right down there with the odds a cataclysmic disaster will obliterate humanity come 2012.  (Pretty much impossible, in other words.)

    I got a healthy reminder of this last week when a bug expert—an entomologist, in proper scientific parlance—by the name of Benoit Guenard turned me on to some photos of a truly bizarre genus of ant called Myrmecocystus.  A slice of one of those photos—a group of jaw-droppingly obese honeypot ants hanging from the roof of a nestbecame our most recent “What On Earth is That?”

    This particular type of ant, which lives in deserts, is like something out of The Matrix.  When food is plentiful, honeypot colonies select certain workers—entomologists call them repletes—to serve as food receptacles for the group. The other workers tuck the repletes away in a safe spot, and then literally stuff them with food until the back sections of the repletes literally swell up like water balloons.

    Grape-sized repletes so fat they cannot walk are common. When food gets short, hungry workers just wander over to a replete, poke and prod it a bit, and wait for it to upchuck lunch. If that’s not bizarre enough, it turns out that rival honeypot ant colonies have a habit of raiding one another and plundering–then enslaving–repletes.  Stranger yet, it’s not just ants that have a taste for repletes; they’re something of a local delicacy among certain tribes in Australia.

    Guenard, it so happened, was the perfect guy to ask about weird ants such as Myrmecocystus. He is in the midst of—get this—an effort to classify all the ant genera in world. That may not sound like much, but it’s an enormously ambitious task when you consider that biologists have yet to name something like half of the ant species scurrying around us.  

    Nobody knows the total number of ant genera in the world, or species for that matter, Guenard tells me, since biologists have never managed to cobble together a systematic search at the scale required. That’s not for lack of effort. In the nineties, an ambitious effort to name every single species on Earth (not just ants but all species) in a mere 25 years—the equivalent of a Moon shot for taxonomists–flamed out when the tech bubble burst and the project lost its funding. Other efforts to classify smaller bits of ecological real estate have suffered similar fates.

    Still, there are biologists out there like Guenard doing their best to continue counting. Guenard, a graduate student at the University of North Carolina, participates in the Global Ant Diversity Project, an effort led by his adviser Rob Dunn and sponsored, in part, by NASA. (I first met Dunn at a NASA-sponsored Ecological Forecasting conference where he was explaining how he uses satellite data to predict global patterns of ant diversity. Check out this PowerPoint if you want to learn more about how that works). 

    Guenard updates the growing ant database as new information turns up in the scientific literature, but he also keeps an astonishing website and blog that brims with eye-popping photography and commentary about ant species that I’m willing to bet you never knew existed. Take a look, for example, at these Pachycondyla chinensis doing battle with some hapless-looking termites. Or look at this pint-sized worker intimidating a hermit crab dozens of times its size. 

    I certainly couldn’t get enough ants from the website, so I gave Guenard a few calls this week to pick his brains about ants and honeypot ants in particular. Here’s a clip from our conversation in which we discuss, among other things, the scientific value of ant licking, replete raiding, and how to tickle an ant to make it spit.

    –Adam Voiland, NASA’s Earth Science News Team

    Earth Buzz: Summer Temps, Icy Interactive, and More

    How Warm Was This Summer?
    …The 4th warmest on record. The Goddard Institute for Space Studies has all the details.  (NASA, Earth Observatory, GISTEMP)

    Interactive Ice
    The world’s ice–on both sea and land–is changing.  See it with your own eyes. (Eyes on the Earth)

    December 2012
    You’re not going to die.  The world’s not going to end.  Can we talk about something else now, please? (
    JPL Video)

    G. Projector, What?
    You’ve never heard of it, but it’s the best map processing software on the internet.  (
    Elegant Figures)

    Inside AERONET
    Goddard’s Brent Holben offers a tour of the robots on his roof (NASA Explorer)
    Venus + Moon + Lake
    …Equals a breathtaking photo. (Earth Science Picture of the Day)
    Tweet of the Week
    Look mom, no Photoshop! Check out this awesome image from our friends @APOD An Airplane in front of the Moon  (NASA_GoddardPix)
    –Adam Voiland, NASA’s Earth Science News Team
    Summer 2010 temperature image courtesy of the NASA Earth Observatory

    What On Earth (Sound) Was That #4? Seismic Music From Earth, Of Course…

    Last week, we posted our first mystery sound in our latest installment of “What on Earth is That?”> We had some interesting guesses; one reader guessed the noisemaker was an earthquake and another guessed it was a calving ice. The answer is somewhere in the middle.

    Giant icebergs may sink ships, but they also have their weaknesses. The sound you heard is the seismic signal recorded in October 2005 when a monstrous iceberg drifting off the coast of Antarctica’s Cape Adare crashed into the previously unknown Davey Shoal and broke apart. (Science News covered the collision in this July article.)  The full length of the audio file, sped up by a factor of 100, can be heard below. Within just 90 seconds, you can experience the full 2.5-hour event.

    The “tap, tap, tap” is from cracks propagating through the massive chunk of ice. The effect is similar to what you hear if you drop ice cubes into a glass of water. The cracking noise crescendos until about 1:15, followed by a subtle hum resembling a muffled chain saw. That noise, from the phenomenon of ice pieces rubbing against each other, becomes most noticeable after the breakup. The same saw-like noise heard prior to 1:15 is thought to be the bottom of the berg rubbing on the shoal.

    The audio comes from a study published June 18 in Journal of Geophysical Research. Looking at images from the Moderate Resolution Imaging Spectroradiometer on NASA’s Terra and Aqua satellites, the team noticed that between 1989 and 2005, at least three large bergs drifting off Cape Adare had suddenly stopped and broke apart. To discover the cause behind the bergs’ unusual behavior, the team turned to an iceberg called B15A.

    Fortunately, plenty of information about the behemoth berg, which measured about 820 feet vertically and spanned some 75 miles by 19 miles, was available. Before the breakup, scientists had deployed an instrument package on B15A that included GPS and a seismometer. Later, a separate research group mapped the seafloor topography within the same area. “We knew from breakup that there ought to be something there,” said Seelye Martin, of University of Washington in Seattle, who led the study.

    Overlaying the satellite images on the seafloor map, researchers recreated the series of events. On October 28, the berg hit the top of an underwater shoal 5.6 miles long and 705 feet below the surface at its highest point. The seismic information, heard in this post, matched the collision observed in the satellite imagery. Listening to the seismic music of the Earth is not new; geologists have long listened to the “rock music” of seismic waves from earthquakes. “But the iceberg has a very different signature,” Martin said. “Earthquakes sound like a big boom or slip, while in this case you can actually hear something breaking up.”

    So what does it all mean? “It’s an interesting result, but it’s not a world changer,” Martin said. “We now know a little more about the obstacles — and sound — of some ill-fated icebergs leaving the Ross Sea.”

    — Kathryn Hansen, NASA’s Earth Science News Team

    Images and sound are courtesy of Seelye Martin, University of Washington

    Behind the Scenes With Scientists Who Created A Global Air Pollution Map

    Yesterday, NASA posted an article about a new global map of health-sapping PM2.5 air pollution. The Dalhousie University researchers who made the map used data from NASA’s MISR and MODIS satellite instruments, as well as information from a computer model called GEOS-Chem. You can read the news story here (or the accounts from Wired, Public Radio, and UPI), but we also wanted to share some of the audio from our interview with the scientists for those who want more details. The scientists being interviewed are Aaron van Donkelaar and Randall Martin; the person asking the question is Goddard-based science writer Adam Voiland.

    What was the most interesting thing you found from this analysis?  

    Why go to the trouble of making this map?

    What’s the heavy band of particulate matter in Africa? Is dust bad for our health?

    Martin: There’s no lower bound on health effects

    Have other researchers done this kind of analysis?

    Are these data ready for prime time?

    How did you combine data from both satellite instruments?

    –Adam Voiland, NASA’s Earth Science News Team

    Lightning Never Strikes Twice, But…

    Though the old adage that lightning never strikes twice generally rings true,apparently lightning can strike in very short order in more than a dozenpoints alongside one another as it did near Keota, Colorado on August6. Photographer Robert Arn captured this bedazzling
    time-lapsed display of lightning over less than 30 seconds across Pawnee National Grasslands while awaiting darkness to fall at a stargazing party.

    Speaking of flashes of brilliance, far from the prairies and big skies of the Plains, NASA’s Lightning Instrument Package, or LIP, flew aboard an unmanned, storm-chasing Global Hawk aircraft earlier this month over the Gulf of Mexico and the Atlantic Ocean detecting and documenting lightning during intensifying hurricanes. LIP and 14 other instruments were part of the Genesis and Rapid Intensification Process mission, commonly called GRIP, which drew to a close this week. Scientists expect the GRIP field experiments will eventually yield the most comprehensive data about hurricanes to date once scientists analyze 40 flight days’ worth of new information.

    NASA’s Earth Science Picture of the Day Web site featured the white lightning strikes above on September 7, 2010. To see more images recorded by amateur and professional photographers and to learn more about Earth Science Picture of the Day, click here.

    — Gretchen Cook-Anderson, NASA’s Earth Science News Team

    Image Courtesy of Earth Science Picture of the Day; Photo by Robert Arn  

    What on Earth is That? #2

    (Please post your guesses and your name in the comments, and we’ll give the answer next week…)

    Here at What on Earth, we’re constantly stumbling across interesting photos, videos, and audio clips from NASA’s exploration of our planet (be it from space, the field, or the lab.) Whether it’s a satellite montage captured from thousands of miles up, the roar of our B-200 research aircraft, or a microscopic view of a cloud droplet, there’s literally always something strange and wonderful passing across our desks.

    To have a little fun (and spare all that fascinating stuff from the circular file), we’re going to post snippets of it every now and then, usually on Fridays. What we post will change, but the question to you all will always be the same: “What on Earth is that?”

    Our only hints:

    1) Our picks will always be related to Earth science in one way or another

    2) It will have some relation to what we do at NASA.

    We’ll give you a week to post your guesses, and we’ll post the answer the following Friday. In the meantime, check out the answer to What On Earth is That #1 here.  

    What on Earth was That #2

    Last week, we asked you to identify the flecks in a video posted to What on Earth is That #2, and we received all sorts of replies. The correct answer?

    They may look like twinkling stars, but the shimmering flecks in this video are actually some of the tiniest particles in the ocean. This clip shows a complex mixture of the miniscule particles, both organic (living) and inorganic (nonliving) types. The large, fern-shaped specimen on the lower right is a type of phytoplankton. Some of the other flecks are likely bacteria and viruses.

    Did you notice the slight vibrating motion that makes all the specks look like they’re flickering? That’s caused by random collisions with atoms, a phenomenon called “Brownian motion.” By measuring the distance each particle is pushed around, it’s even possible to infer particle size, which is important for understanding how the particles scatter sunlight in the ocean and for interpreting what ocean-observing satellites “see.”

    Image and video Information: This sample was pulled from the Arctic’s Chukchi Sea on June 29, 2010, as part of NASA’s ICESCAPE mission. Kuba Tatarkiewicz, of the Scripps Institution of Oceanography, captured the action with a NanoSight instrument — a camera, microscope and viewing unit that the team adapted for use during the ICESCAPE oceanographic voyage.

    -Kathryn Hansen, NASA’s Earth Science News Team

    What On Earth Was That #3 ?

    Last week, we showed you this mystery image. What was it? As a number of readers—including Brad Halderman (comment #3), Budi Prasteya (comment #7), and others—correctly guessed, you’re looking at a cropped version of one of the famous “sailing stone” tracks located on the Racetrack Playa in Death Valley National Park.

    Since the 1940s, researchers have documented the distinctive furrows behind rocks at a number of dried out lake beds in Death Valley. Yet, nobody has actually seen the rocks move or proven definitively how the tracks form. Animals, earthquakes, and gravity have all been ruled out. Some researchers have suggested that the composition of the rock might be a factor, but tests have shown most of the boulders are run-of-the mill dolomites, basalts, limestones, gneisses, and schists that aren’t unusually slippery.

    One of the best theories left standing: a combination of wind, mud, and ice. The area receives strong gusts of wind, and episodic bursts of rain that can create slicks of mud for brief periods. During cold weather, thin layers of ice can carpet the playa, and many scientists believe that wind, with the help of ice and mud underneath—has enough force to slide the boulders.

    Though science journalist Brian Dunning has an interesting video that shows the movement of ice on the playa, no one has filmed wind actually moving the rocks. In the meantime, researchers (including a recent group sponsored by NASA) continue to investigate the phenomenon, as a NASA news story reported earlier this summer. 

    –Adam Voiland, NASA’s Earth Science News Team

    The image above is available through  NASA Goddard’s photo and video flickr feed