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Why understanding something smaller than a pinprick (an aerosol particle) is the key to something as big as a planet (global climate)

February 23rd, 2011 Comments off

UPDATE MARCH 4: Sadly, Glory launched this morning but did not reach orbit because the payload faring did not separate. The faring protects and encloses the satellite during launch and initial ascent. With this extra weight onboard, the launch system was unable to reach orbit and landed in the ocean. Condolences to the mission team that spent years designing and building the ill-fated Glory spacecraft.


mosaic of images and art associated with glory mission

To learn anything, you first need to know what you don’t know. Let’s call them the “known unknowns.”

In climate science, one of the thorniest known unknowns is the impact of aerosols, microscopic particles that drift in the atmosphere absorbing and reflecting energy, and tweaking clouds. My colleague Adam Voiland — Goddard Space Flight Center’s chronicler of all things aerosol — explained it this way in one of his many fine web features and press releases on the topic:

“The particles can directly influence climate by reflecting or absorbing the sun’s radiation. In broad terms, this means bright-colored or translucent aerosols, such as sulfates and sea salt aerosols, tend to reflect radiation back towards space and cause cooling. In contrast, darker aerosols, such as black carbon and other types of carbonaceous particles, can absorb significant amounts of light and contribute to atmospheric warming.”



The Glory mission, which is scheduled to go into orbit this week, will attempt a much better understanding of aerosols and — climatologists hope — lead to needed improvements in the computer simulations that predict where earth’s climate is heading in the coming decades.

But for my part, the Glory mission actually takes me back a decade or so, to the mid-1990s when I worked for a now-defunct science magazine called Earth. The UN’s Intergovernmental Panel on Climate Change (IPCC) had, in 1995, published its Second Assessment Report. Using a newfangled thingie called the World Wide Web, science reporters eagerly poured over the IPCC report’s many hundreds of pages, trying to make sense of it all.

One issue that stood out was — you guessed it — the role of aerosols in global climate change. Here’s what the panel authors said on page 525 of a portion of the IPCC report, Working Group I: The Science of Climate Change.

“Atmospheric aerosols (Chapter 2) also play an important role in the Earth’s radiative budget. There are fairly reliable estimates of the amount of sulphur burned but these do not translate directly into number density of aerosols, for which the size, hygroscopic and optical properties, as well as their vertical, horizontal and temporal distributions, have not been well observed.”



Allow me to translate: It’s saying that we know how much sulfur-containing fuels we burn (coal, for example), which produces sulfate particles that have a cooling effect on climate; but that doesn’t tell us how much of this aerosol is produced, how much energy it reflects, and where it is.

And on page 526, the report tells us why we should care about aerosols, from a practical point of view:

Thus, at present the uncertainty in aerosol radiative forcing is the largest source of uncertainty in the total radiative forcing of climate over the past industrial period. Since aerosols are very patchy in their distribution, they could create significant regional climate changes regardless of their effect on globally averaged forcing.



{If you have a lot of time on your hands or need something very heavy to hold doors open, download and print Working Group I: The Science of Climate Change by clicking HERE.}

So here is the punchline for this week: Glory will provide data needed to help resolve uncertainties about aerosols and climate. The hope is that computer models will be able to make better predictions of where Earth’s climate is heading.

If you want to learn more, here is a series of recent videos about the Glory mission. And don’t miss this and this web feature about Glory, by Adam Voiland.






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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.



Happy birthday, EO-1. . . Ten years and a day ago, the first Earth observing satellite of the New Millennium program launched into orbit

November 22nd, 2010 Comments off
EO-1 satellite image of the World Trade Center in flames on 9/11

EO-1 satellite image of the World Trade Center in flames on 9/11

EO-1 logoOn November 21, 2000, a satellite called Earth Observing 1 (EO-1) was launched on a Delta rocket from Vandenberg Air Force Base. It was the first satellite in NASA’s New Millennium Program Earth Observing series.

***UPDATE: If you are interested in the science EO-1 has delivered for the past decade. check out the outstanding feature article on NASA Earth Observatory. It also includes many more images from EO-1.***

EO-1’s job was to test and validate new technologies that could be used in future Earth-observing spacecraft. For example, EO-1 went into orbit with a special antenna that uses no moving parts and instead uses software to steer the data beam back to the Earth antenna, and at very high data rates.

EO-1 also has a souped up solar array to produce more than twice the power per square inch than a typical array at that time. EO-1 also tested a reliable, lightweight electromagnetic thruster. And the spacecraft demonstrated the ability to fly in close formation with another Earth-observing satellite, Landsat-7. These are just some of the revolutionary satellite technologies on EO-1.

Engineering better satellites is important, but in the past decade EO-1 has also beamed down some pretty spectacular images of our planet. Here are a few.

The dense urban core of the District of Columbia

The dense urban core of the District of Columbia


Pearl Harbor, Hawaii

Pearl Harbor, Hawaii


The Alaskan interior

The Alaskan interior


The Aspen Forest Fire near Tuscon, Arizona in 2003

The Aspen Forest Fire near Tuscon, Arizona in 2003

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.

Listening to the music of volcanoes with Milton Garces

November 5th, 2010 Comments off

woe_logoCheck out my guest post on NASA’s What On Earth blog. Last week, we posted a spooky Earth sound and asked readers to guess what it was. It was not a bird, a plane, a balrog, or even a humpbacked whale. It was a singing volcano, recorded by University of Hawaii scientist Milton Garces.

To sample the sound and read my posted about volcano monitoring with NASA and Garces, read the What On Earth blog post.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.



W3Counter


Gogblog Monday Video Rewind Picture Show: What Fueled 2005’s Hurricane Season from Hell? Here it is A to Z.

September 13th, 2010 Comments off
27stormsTitle

CLICK ME to open a new window and watch the video

It’s hurricane season. And if you live on the Atlantic Coast, like gogblog, you sometimes get to wondering. . . What gives birth to these giant storms? How do tropical storms grow into hurricanes? Why do some fade early, while others reach category 5?

Watch this colorful and dynamic Goddard TV web short to get the answers: 27 Storms: Arlene to Zeta. It looks back on the destructive 2005 hurricane season — the one that gave us Katrina and the New Orleans catastrophe. The season birthed an astounding 27 named storms, beating 1933’s record of 21 nameable storms.

Got FiOS or some other fast Internet access? Go to the Scientific Visualization Studio website to download high-resolution versions of the video.

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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.



Hidden Heroes: 80 percent of the time, Jim Foster thinks about snow. But the rest of the time is consumed by his joy and his jailor — the earth science picture of the day

July 22nd, 2010 6 comments
got moon?

got moon?

Jim Foster is a senior scientist at NASA Goddard who studies snow 80 percent of his work time. “I’m in the Hydrological Science Branch, and my research deals with snow hydrology, also related to snow and climate,” he explains. “I’m involved in projects trying to better derive how much water is stored in snowpacks — seasonal snow not glaciers.”

Less well known is what he does with the remaining 20 percent of his time: EPOD: the earth science picture of the day website.

After many months of following the EPOD site and re-posting its images on blogs and Facebook pages, I finally noticed that the guy running the show is right here at Goddard, over in Building 33 around the corner from me. So I called him.

Foster explained that 10 years ago, he was asked to manage a new website featuring images related to earth science. This became EPOD.

EPOD rocks

EPOD rocks

EPOD echoes APOD — the Astronomy Picture of the Day. To say that APOD is wildly popular is an understatement. It was founded in 1995 by Robert Nemiroff and Jerry Bonnell. Jerry is a scientist here at Goddard.

In 2000, Foster and the rest of the (small) EPOD team launched the site and put out a call for images. It took a while for things to pick up. But now there is no shortage.

“They come from everywhere,” he says. “We’ve received contributions from each continent. Sometimes it’s scientists, but most of the time just people have an interest in science, or folks that don’t have an interest in science but have a camera.”

lightning_epod_152

lightning strikes

Each EPOD entry includes a caption, links, time and date when the photo was taken, and latitude and longitude coordinates. Often Jim has to research the details before posting.

The Universities Space Research Association (USRA) hosts the website on its server. (USRA is a private, nonprofit consortium of 105 universities offering advanced degrees in space- and aeronautics-related disciplines.) At USRA, Stacy Bowles handles the technical aspects of the site and runs the relatively new EPOD Facebook page.  And a former newspaper marketing specialist in Seattle, Stu Witmer, contributes to EPOD as an unpaid volunteer. He provides grammar checks, proofreading, and other valuable support. “Stacy and Stu help things run smoothly,” Foster says.

ISS transit_epod_152

sun crosser

Since last fall, NASA’s Earth Observatory has provided funds to cover 20 percent of Foster’s salary to work on EPOD. But there’s more to it than that. There is the more intangible element of commitment.

Day after day for most of the past decade, the ravenous mouth of EPOD had to be fed with a new image and associated information and web links. And through rain, hail, sleet or snow, Foster has delivered. Before going on vacation or traveling for work, he had to build up a queue of EPODs. No exceptions.

cloud_epod_202

cloudy weather

In this sense, EPOD has been Foster’s joy and his jailor. And I think it makes him one of the unsung heroes of science on the web. You know, the people who just do what they do, day after day, usually for only the satisfaction of doing it, often with minimal or no financial support at all — or in some cases, just the reward of feeding an obsession.

There are many such people on the web. But countless earth enthusiasts all over the planet can thank one man for sustaining EPOD for a decade: Jim Foster at Goddard Space Flight Center.

Got any cool earth science images? Send them to Foster. The contact form is on the EPOD website.
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OH AND DID I MENTION? All opinions and opinionlike objects in this blog are mine alone and NOT those of NASA or Goddard Space Flight Center. And while we’re at it, links to websites posted on this blog do not imply endorsement of those websites by NASA.