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Earth Matters

News Roundup

June 30th, 2011 by Adam Voiland

No Ordinary Sight
If you’re driving along Interstate 95 between Washington and Baltimore this July, don’t be alarmed if you see a large aircraft hurtling toward you from above. It’s not a a terrorist attack or a pilot dozing at the stick; it’s just NASA’s P-3B doing air quality research. The 117-foot plane is the workhorse for a field experiment that kicked off this week. The plane will fly along heavily-traveled roadways and make conspicuous spirals over ground stations in northeastern Maryland. “We’re trying fill the knowledge gap that severely limits our ability to monitor air pollution with satellites,” said James Crawford, the experiment’s lead scientist.

Still Warming Folks
The more things change, the more they stay the same. NOAA released its annual State of the Climate Report (PDF) this week, and the findings won’t surprise anybody who has cracked a newspaper open in the last decade. Last year was the second warmest on record since official record-keeping began. The world’s glaciers lost mass for the 20th year in a row. Arctic sea ice shrank to its third smallest area on record. I could go and on – NOAA offers details on a total of 41 global climate indicators in the report — but The Washington Post already has it covered.

Near Misses
Asteroid 2011 MD offered a reminder last week that catastrophe could strike unexpectedly. The asteroid arrived out of the blue – er, black – and buzzed within 7,500 miles of Earth. The good news, as the Christian Science Monitor reported, is that the asteroid was small enough that it would have burned up in the atmosphere even if it had been headed for Manhattan. Meanwhile, in other space flotsam news, the crew of the International Space Station had a close call with a hunk of debris this week.

Sea Ice Today, Gone Tomorrow
After reading this post from the “Open Mind” climate blog, I have a feeling that after regaling my future grandkids with stories of life before cell phones and Facebook, I’ll be telling them about the days when we actually had summer sea ice in the Arctic. Tamino’s post walks through what scientists know about the rapid decline in sea ice extent and volume due to satellite, aircraft, and submarine research. In sum, the trends are pretty grim. “The phrase ‘death spiral’ comes to mind,” the blogger noted.

Never a Dull Day for Science
Every field expedition has its hiccups, and this time they’ve come early and often for the Healy, the Coast Guard icebreaker conducting NASA-sponsored research in the Arctic. While still in port in Alaska, a magnitude-7.2 earthquake and subsequent tsunami warning sent the crew and scientists scrambling for high ground. A few days later, a distress signal from a sinking tugboat sent the Healy off its planned route to conduct a search-and-rescue mission. A Coast Guard helicopter rescued the tugboat’s stranded crew, and now the icebreaker is back on course. Science writer Kathryn Hansen is on board blogging about the drama.

A Mesmerizing View
The simplicity, beauty, and calming voice of the narrator in this video of Earth from the vantage point of the International Space Station makes me want to watch it again and again. And it appears I’m not alone – the clip had already registered more than a million views when this post went live in late June. Meanwhile, Popular Science reported that a Canadian company has plans to stream a high-definition video feed from the space station later this year. “The system will work as a sort of mashup between Google Earth and YouTube,” the founder of the company said. Sign me up…

[youtube rj18UQjPpGA]

The Two-Minute Carbon Cycle

June 24th, 2011 by hriebeek

In the process of researching a feature for the Earth Observatory, I always come across fascinating tidbits that just don’t quite fit into my article. For instance, there’s this great carbon calculator tool from the University of Wisconsin-Madison.

Early during the development of the recent carbon cycle feature, I heard NASA scientist Peter Griffith speak to a group of National Park rangers. Most scientists speak from slides full of data, and I fully expected Peter to do so as well. But he didn’t. He stood at the front of the group with just a banana and a piece of coal. In a matter of minutes, he demonstrated both the carbon cycle and why burning fossil fuels has such a big impact on the carbon cycle. It was a simple and powerful demonstration. At the end, he concluded that by burning fossil fuels, we move carbon from the slow, old carbon cycle to the fast, young carbon cycle.

The talk shaped the way I think about the carbon cycle. And while the analogy never made it into the article, the way he organized the ideas and his conclusion did. As I was finishing the article, a colleague shared this two-minute video Peter made based on that talk. Enjoy!

[youtube uStoBFtjy8U]

News Roundup – Solstice Edition

June 21st, 2011 by Patrick Lynch

Maunder’s Return
This sounds like a straight-to-DVD sci-fi title. But the National Solar Observatory announcement last week that the Sun could be entering a grand minimum should probably be filed with cable TV’s “What Would Happen If…” documentaries. The last time the Sun went quiet for a long stretch – dubbed the Maunder Minimum — the world plunged into the “Little Ice Age.” But this time, there will probably be very little impact because of the long-term warming that is already underway, says Georg Feulner of the Potsdam Institute for Climate Impact Research.

Where is Aquarius?
While we are waiting to get the first bits of data from Aquarius, NASA’s latest Earth observing satellite and first to measure ocean salinity, you can check out where the Aquarius/SAC-D spacecraft is orbiting at this site. Aquarius successfully reached orbit on June 10, after a launch from Vandenberg Air Force Base.

Predicting Climate Changes
Timothy Lenton of the University of Exeter (UK) argues that significant climate tipping points – when earth systems pass a point of change that is large and largely irreversible – are more predictable than scientists have thought. “Recent work shows that early warning of an approaching climate tipping point is possible in principle,” Lenton writes in Nature Climate Change, “and could have considerable value in reducing the risk that they pose.”

Wallowing in Fire
The Wallow Fire in Arizona became the largest wildfire in the state’s history last week. Discussion of the role a warming climate will play in increased wildfire began spreading like…nevermind. New West wrote about the future of the Rockies and fires, based on some recent and fascinating paleo-fire research from NASA; The Washington Post’s Capital Weather Gang dug through a National Academies of Science report from 2010 that also delved into topic.

Plankton on Ice
A team of 47 scientists will take an icebreaker, the Healy, to the extreme environment of the Arctic Ocean for about six weeks this summer, as the second and final leg in a NASA field campaign called ICESCAPE. The cruise is designed to study how ongoing climate changes are affecting ocean chemistry and physics and marine life. Check out science writer Kathryn Hansen’s blog from the ship beginning this week and lasting throughout the research cruise. (The blog updates will begin as soon as Kathryn gets aboard ship in the ironically named Unalaska, Alaska.)

A Plate of Water
And we thought we would share this from our friends at Earth Science Picture of the Day as a bit of solstice joy…

Earth Observatory publishes many images of floods. The 2010 monsoon floods in Pakistan and 2011 floods in the Mississippi and Missouri basins have received a lot of coverage.

But we don’t publish photo-like images of every flood, and many readers wonder why. The severe floods affecting China this month are a perfect example. So far, we have only been able to visualize the rainfall in the region.

Multiple factors limit our ability to show floods, but perhaps the biggest is cloud cover. In a hurricane image, the clouds are the story. When it comes to flooding, clouds often hide the very trouble they have caused. An overflowing river or standing water on agricultural fields cannot be observed until clouds clear out of the way. Sometimes cloud cover lingers until the high water has receded.

Clouds obscure most of this MODIS image acquired on June 18, 2011.

And just as some parts of our planet are frequently sunny, other places—including some of the places frequently affected by floods—are consistently cloudy. (See the Cloud Fraction global map for more information.)

The duration and size of events also limit the ability of satellites to see flooding. Destructive as they are, flash floods usually occur so quickly that satellite sensors such as (MODIS) have little chance to observe them. Likewise, a flood can cause serious damage without spanning a wide enough area to be detected by a satellite sensor. When flood waters outlast the storm system that deposits them, a satellite sensor’s ability to observe flooding is improved, but not guaranteed.

Another factor that limits flood observations is land cover. Densely forested environments often hide floods from satellites. Flood waters show up better in grassland and arid environments. High-resolution satellites are successful in observing flooding in some urban areas.

All of these factors are complicated by something else. In the case of hurricanes, wildfires, and dust storms, the events by themselves are obvious enough for anyone to see. Flooding is different. Except for high-resolution shots from urban areas, flooding can be difficult to detect without a “before” image for comparison. So to show flooding, the EO team must not only find a cloud-free image of the flooded area, but also a cloud-free image of the same area under normal conditions.

Flooding in southern Mexico on September 8, 2010 (top), is much easier to detect when compared to pre-flood conditions on September 9, 2009 (bottom).

When prolonged, heavy rain falls at low latitudes, we have a reasonably good chance of seeing it, thanks to the Multisatellite Precipitation Analysis produced at NASA’s Goddard Space Flight Center. The analysis estimates rainfall by combining measurements from many satellites and calibrating them against rainfall measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite. The heavy rain in China has occurred in the right place and has lasted long enough to be visualized. Cloud cover and land cover, however, have hampered our ability to detect flooding on the ground. We may yet find imagery of this natural disaster. We will keep looking.

If you want to see global warming’s signature, look to the Arctic. Up north, the air is warming and the ice is melting. As all of that reflective ice goes away, the Arctic Ocean is soaking up more sunlight, further enhancing warming. Melting Arctic ice is also contributing significantly to sea level rise.

For two decades, scientists have predicted these things would happen as the Earth warms, and now we see that the Arctic is changing much as expected. A new assessment report released by the Arctic Monitoring and Assessment Program lays out the facts about many of the changes. AMAP is a working group of the Arctic Council, an intergovernmental organization consisting of eight Arctic nations.

Copyright: Henrik Egede Lassen/Alpha Film

The report provides 15 key findings, and many of them are based on NASA satellite observations or science we’ve talked about on the Earth Observatory. Here’s a summary of the key findings:

  1. 1. The past six years (2005 – 2010) make up the warmest period ever recorded in the region, and these warm temperatures are causing changes.
  2. 2. Changes in snow cover and sea ice are interacting with the climate to increase warming. (More on this topic in a recent image of the day.)
  3. 3. Snow and sea ice cover a smaller area and are present for a less of the year, while permafrost is warming.
  4. 4. The largest and most permanent bodies of ice in the Arctic, including multi-year sea ice, mountain glaciers, and the Greenland ice sheet, have melted faster since 2000 than in the previous decade. (The Greenland work was also the topic of a recent image of the day.)
  5. 5. Model results reported in the last IPCC report underestimated how quickly sea ice is changing.
  6. 6. By 2050, snow will be deeper in places, but last for a shorter period of time.
  7. 7. The Arctic Ocean will be nearly ice-free during the summer within this century, probably within the next 30-40 years. (That’s not a hard prediction to believe considering the change seen over the last decade.)
  8. 8. Changes in the Arctic snow and ice fundamentally change ecosystems, destroying some habitats, which will impact Arctic peoples.
  9. 9. Observed and predicted changes in the Arctic will pose both challenges and opportunities to Arctic societies.
  10. 10. Transport in the Arctic will change, with impacts on day-to-day life and commercial activities.
  11. 11. Arctic infrastructure will probably be damaged as permafrost and near-shore sea ice melt.
  12. 12. Loss of snow and ice and the release of greenhouse gases from melting permafrost will enhance global warming.
  13. 13. Melting glaciers and ice sheets contributed more than 40 percent of the global sea level rise (about 3 mm per year) between 2003 and 2008. Further melting will contribute substantially to the 0.9 to 1.6 meter sea-level rise expected by 2100.
  14. 14. Everyone in the Arctic will have to adapt to climate change.
  15. 15. More research and monitoring are needed to answer questions about how fast the Arctic will change in the future.

This sort of assessment report is interesting not because it presents new science, but because it provides a rare full-picture view of what is going on. To me, the take-home message is that climate change in the Arctic is a reality and that changes are beginning to affect the rest of the planet by amplifying warming and pushing sea levels up.

The Arctic Monitoring and Assessment Program (they call themselves AMAP) also released a series of photographs and videos (3 minute and 15 minute versions) that show change. Warning—the video files are huge and take a very long time to download, even on a fast connection.

My favorite photo, shown above, illustrates the sheer volume of melt in a single spot on the Greenland Icesheet. The center of the image is a drained meltwater lake near Helheim glacier in southeast Greenland. The walls of blue ice are surreal.

I also really like Konrad Steffen’s photo of a crevassed area near the front of the Jakobshavn Glacier, West Greenland.

© Konrad Steffen/CIRES, University of Colorado

In satellite images, the glaciers look like smooth rivers of ice to me. This photo shows that the river isn’t so smooth!

Earth at the Movies

June 12th, 2011 by Mike Carlowicz

Science writers and producers from across NASA recently sponsored an Earth Day video contest for the public. The theme was “The Home Frontier,” and the idea was to create videos that expressed what NASA Earth science means to you. Many people don’t realize that one of our agency’s most important missions is to study the planet we are already living on.

The winner of the inaugural contest was Fiona Conn and colleagues, who offered up “One Earth.”

[youtube J75Nm2mTT0Y]

Other entries from the contest can be found here.

What do you think? Which video gets your vote? I am partial to this one by Lewie Kloster (@beakerlab). Maybe it’s because I was reminded of comic Stephen Wright, who used to say: “Every so often, I like to go over to a window, look up at the sky, and smile for a satellite picture.”

Missed your chance to enter the contest? Don’t fret. NASA’s earth science storytellers hope to make this a yearly event, so you’ve got 10 months to get ready for Earth Day 2012. Start saving copies of your favorite Earth Observatory images now.