Another kind of image of the day

Every day we bring you a different view of Earth, as only NASA can see it…from high above, and usually from space.

One of our colleagues has also been working since 2000 to bring you breathtaking views of Earth…albeit, from a perspective that’s a bit closer to the ground. Together with a few professional helpers and hundreds of amateur photographers, atmospheric scientist Jim Foster of NASA’s Goddard Space Flight Center offers up the Earth Science Picture of the Day. Here is a recent offering that caught my eye:

Foster and photographer Jimmy Hamilton wrote: “Airplanes are great places to observe sunsets as long as you have a window seat…The photo above was taken mid-flight somewhere over the Atlantic Ocean, on a flight from the Dominican Republic to London, England. I was presented with this startling view when I popped open the window blind. The Sun was illuminating the base of the clouds producing a seemingly upside down sunset.”

Check out more Earth photos, and learn how to submit your own, by visiting EPOD.

Posted in Uncategorized | 2 Comments and counting

Q & A: The Midwest Drought with Richard Seager

This drought severity map was updated on August 21, 2012. It was generated by the National Drought Mitigation Center. For more information about the map, please visit this site.

NASA Earth Observatory writer Adam Voiland spoke with Columbia University climatologist Richard Seager about the widespread drought currently affecting North America. 

The current dry spell has been called a “flash drought.” Has it really come on that quickly or as a surprise?  
No, I wouldn’t say it has been a surprise to those of us who closely watch the seasonal annual forecasts and the La Niña and El Niño forecasts. I don’t think that’s something that has come across in a lot of the news coverage. It’s not like this has come on that quickly.

Remember all of those stories last summer about the drought in Texas? The drought did ameliorate some in the winter, but then the interior Southwest dried out, which is exactly what you would expect during a La Niña winter.  And then it really expanded north in the late winter, which was more surprising.  Now it’s gotten up into the Midwest and even up into New York where I am. I think the extension toward the Northeast, which is remarkable, has been caused by some random atmospheric variability that’s being added on to the forcing coming from the tropical Pacific Ocean.

A recent IPCC report on extreme weather events and climate change indicated that the link between climate change and droughts in North America isn’t straightforward. Do you think there is a link between the two?
I don’t think you can make a direct link because the natural variability is so tremendous. It is really hard to definitively detect human-induced changes for a specific region. Climate forecasts do predict that much of the southwest and the southern plains will get drier, but the human-induced component should be relatively small in comparison to the natural variability. However, we do have a background warming trend in the Southwest, so when these droughts come along, they happen in a warmer environment. That adds an extra layer of water stress. I do think that climate change plays an important role by making these La Niña-induced droughts worse than they otherwise would be.

Is the cause of this drought a lack of precipitation this summer or the lack of snowpack from the winter?
The lack of snowpack has definitely played an important role. Partly because of the La Niña, there was very little snow across the United States this past winter.  We had very little snow melt in the spring, so we entered the summer with much drier soil to begin with. That’s probably  contributing a positive feedback, in addition to the fact that the storm track has shifted way north.

Posted in Uncategorized | 3 Comments and counting

Moonlit Clouds Obscure Indian Blackout

Earlier this week, as India endured the worst blackout in its history, many readers and members of the media asked us to show the vast country without lights. Just a few weeks ago, Earth Observatory showed the world what the Mid-Atlantic United States looked like before and after a massive storm-induced blackout. (We also showed the city lights of London.)

But this week, there was nothing to see…at least from space. Here is India before the blackout, as viewed through the day-night band of the VIIRS instrument on the Suomi-NPP satellite:

July 30, 2012

One night later, the view was not much better…

July 31, 2012

What’s the problem? It’s monsoon season in India, which means near-constant clouds and rain…and very little visibility for satellite instruments observing visible wavelengths of light.

Surely there is a blackout under those clouds, as nearly half of the nation (and 600 million people) went without power for parts of two days. You can catch a faint hint of more or less light between July 30 and 31 in the northeastern portion of the images. But mostly, the view is clouds, clouds, and more clouds. They are lit by moonlight, at least.

Posted in Uncategorized | 2 Comments and counting

Twelve Years of Fires

Besides acquiring photo-like images of the surface of Earth, the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites can detect the anomalously high temperatures associated with actively burning fires. Using this “hotspot” data, John Nelson of IDV Solutions made a map of major fires in the contiguous 48 United States from 2001 through early July 2012.

Image courtesy John Nelson, IDV Solutions.

This map shows not just the locations, but also the intensity of major fires. Nelson has scaled the fires by “units of the typical American nuclear power plant’s summertime capacity.” The most intense fires are yellow, and less intense fires appear in shades of magenta and purple. Graphs in the lower left corner show the proportion of fires by year and by month.

Jessica McCarty, who studies U.S. fire patterns at Michigan Tech Research Institute, observes that the most intense blazes are usually wildfires in forested or peatland areas. Prescribed fires to benefit agriculture and ranching are generally less intense.

A high-resolution version of this image is available here.

Posted in Uncategorized | 9 Comments and counting

Help Find an Alphabet in the Sky

NASA image courtesy Jeff Schmaltz, LANCE MODIS Rapid Response. This image was acquired on July 11, 2012, by the Aqua satellite.

One of the first things that caught my eye when I started checking for interesting satellite imagery yesterday was this: an enormous “V” of smoke draped over northern Canada, as seen by the MODIS instrument on the Aqua satellite. The plume was caused by numerous wildfires burning in the Caribou Mountains of northern Alberta.

At first glance, what looks like a decorative swash on the upper left of the V even reminded me of the look of the N we use on the Earth Observatory to indicate the orientation of an image. It made me think the two might in essence share the same typeface. In fact, the bottom point of the capital V of Adobe Jensen Pro (the typeface of our N) is much wider and curvier than the point in the smoke above. (Wired points out it also looks like the letter Z, which is true if you rotate the image clockwise a bit.)

Still, it’s a memorable image. And it made me wonder: how many other letters have satellites captured momentarily gracing Earth’s atmosphere and oceans? This is the first that I’ve noticed, but I have no doubt there are many more to find given the ceaseless mixing and swirling of clouds, smoke, dust, ice, and even phytoplankton that constantly occurs across our planet.

I think it would be fun to compile a gallery of them, so if you’ve seen a letter (or other typographical mark) in a satellite image, please let me know. Just leave a comment on the thread below. Send a link to what you’ve found, and explain what letter or other typographical mark you think you see.

If you’re feeling especially ambitious, mention what typeface it reminds you of as well. I’ll update this post as new letters come in, and perhaps we’ll eventually have the whole alphabet (plus a good collection of numbers and symbols).  Sending non-English characters is ok: just note what the character is and what it’s called.

Wondering where you can look for imagery besides the EO archives?  Here are a few places to try:

1) NASA Visible Earth
2) The Gateway to Astronaut Photography
3) Jet Propulsion Laboratory Photojournal
4) Scientific Visualization Studio Archives
5) MODIS Image Gallery
6) Landsat Imagery Gallery

Please note: Our gallery won’t likely include many of the high-resolution commercial satellite images that you may have seen on Google Earth because we cannot reproduce those images on our website without buying them. Besides, medium-resolution and low-resolution satellite instruments are actually better for observing large features such as clouds and smoke plumes. Here’s a list of some of the high-resolution instruments that we’ll only be using sparingly, if at all.

Tags: alphabet, smoke, typography
Posted in Uncategorized | 39 Comments and counting

A Unique View of Wildfire Smoke

We publish a lot of wildfire imagery on our natural hazards page (particularly after the wildfire season ramped up recently in Colorado and other states in the western U.S.)  Most of the imagery is acquired during the day by instruments on polar-orbiting satellites: the Moderate Resolution Imaging Spectroradiometer (MODIS) on Aqua and Terra, the Advanced Land Imager (ALI) on EO-1, or the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on Terra.

So it caught our eyes when this image of wildfire smoke at night—captured by the Expedition 31 crew on the International Space Station—turned up on Marshall Space Flight Center’s Flickr page. Faint smoke is visible drifting near Ciudad Juaréz, Mexico, and El Paso, Texas — neighboring border cities along the Rio Grande. It isn’t possible to distinguish the U.S./Mexico border, but a line of lights along Interstate 10—which is slightly north of the border—is visible.  (See this story about city lights viewed from space for a clearer view of Interstate 10 and the border). It’s likely the smoke originated from the Whitewater-Baldy wildfire, a large blaze that has been burning 225 miles to the northeast of El Paso in Gila National Forest.

The photo was taken on June 2, 2012, with a Nikon D3S, a digital single-lens reflex camera identical to what’s available to consumers. A Russian spacecraft  docked to the station is visible on the left side of the image.

Posted in Uncategorized | No Comments yet

Derecho Downs Trees from Indiana Eastward

On June 29, 2012, a long-lived, fast-moving windstorm blew over the eastern United States. The storm started in northwestern Indiana and, over the next 10 hours, traveled roughly 600 miles (1,000 kilometers) toward the East Coast. Wind speeds matched those of an EF-1 tornado in places. The storm uprooted trees, damaged homes, smashed cars, downed power lines, and left more than a million residents of the Washington, D.C. area without electricity.

This photo shows an unusual cloud formation on the leading edge of the June 29 windstorm. Image courtesy Kevin Gould and NOAA.

Meteorologists classified the storm as a derecho—a windstorm associated with fast-moving thunderstorms. A derecho is not a new phenomenon; the term was coined in the late nineteenth century. These storms can rival tornadoes in terms of the damage they cause but, unlike tornadoes, derecho winds generally cause damage in one direction.

The derecho that struck on June 29, 2012, occurred along the boundary of a stable, dry air mass to the north, and a moist, unstable air mass to the south. Areas affected by the southern air mass were suffering a severe heat wave, including record-breaking temperatures in multiple locations. The high heat and humidity provided energy to the strong winds. The thunderstorms sucked up warm, moist air and subsequently returned it in downdrafts. Hitting the ground at tremendous speed, the downdrafts fanned out over the surface, sometimes picking up speed.

The U.S. National Oceanic and Atmospheric Administration (NOAA) provides a primer on derechos, and an overview of the June 29 event. The Capital Weather Gang also provides a summary of the event.

Posted in Uncategorized | No Comments yet

National Research Council Video Series Summarizes the State of Climate Science Research

A  new video series from the National Research Council  summarizes what scientists have learned about global warming and climate change.  It’s difficult to pack decades of complex research into short video snippets, but the makers of these videos have done an excellent job. As you watch, keep an eye out for mentions of the key role that remote sensing has played in advancing climate science. Also, look for the numerous data visualizations produced by the Scientific Visualization Studio at Goddard Space Flight Center that made the cut.

Posted in Uncategorized | 6 Comments and counting

Silent Spring Turns 50

On June 16, 1962, The New Yorker began publishing a serialized version of Silent Spring by Rachel Carson. Spring would eventually turn silent, Carson warned, because widespread pesticide use was killing so many birds that there might be none left to sing. The book provoked a strong reaction from the pesticide industry, but also led to tighter restrictions on pesticide use in the United States and other nations.

Born in 1907, Rachel Carson studied at The Johns Hopkins University and the Marine Biological Laboratory. She was the second woman hired by the U.S. Bureau of Fisheries for a non-secretarial position. In her spare time, she wrote newspaper and magazine articles. Between 1941 and 1955, she published three books about the ocean, leaving the fisheries bureau in 1952 to become a full-time writer. A decade later, she completed the book that made her beloved by some and despised by others.

Rachel Carson in 1944. Image courtesy of the National Conservation Training Archives.

When Carson wrote Silent Spring, dichlorodiphenyltrichloroethane (better known as DDT) was frequently used as an insecticide in domestic and agricultural applications. At the same time, multiple bird species were showing signs of decline. Carson connected the dots between pesticide use, wildlife decline, and human health.

One common misconception about Rachel Carson’s work is that she opposed all use of DDT, even when it could prevent the spread of malaria. Although she described dire scenarios of how pesticides might affect nature and people, she didn’t argue for an end to all DDT use. Instead, she argued for more cautious, targeted uses. A Nature article commemorating the anniversary of her book reported that the pesticide restrictions eventually implemented probably left DDT more effective in fighting malaria because pests had fewer opportunities to adapt and evolve.

Carson faced a firestorm of criticism for her book, but helped spur environmentalism in the United States and abroad. She did not live to see many of the consequences of her work as she had breast cancer when Silent Spring was published and died from it in 1964. As she wrote her book, iconic birds such as the American bald eagle were in decline; but by 2007, the bald eagle was removed from the U.S. Endangered Species list.

To learn more about Rachel Carson, please see the Earth Observatory feature article by guest author Brian Payton.

Reference: Dunn, R. (2012) In retrospect: Silent Spring. Nature, 485, 578–579

Posted in Uncategorized | 1 Comment so far

Tornado Tracks

Tornadoes plague the central and eastern sections of the contiguous United States far more than the western portion. That much is obvious from this map showing 56 years of tornado tracks, from 1950 through 2006.

Image courtesy John Nelson, IDV Solutions.

This map breaks down tornadoes by strength based on the Fujita scale. Stronger tornadoes appear as brighter lines. (An enhanced Fujita scale was implemented in 2007, but these tornado tracks were classified according to the earlier version.)

One prerequisite for tornado formation is humidity, which is much greater in the east than in the west. But topography also plays a role; few tornadoes form over mountainous West Virginia, for instance.

This map was created by John Nelson of IDV Solutions. He obtained the data through Data.gov, which was set up to “increase public access to high value, machine readable datasets” generated by the U.S. government. A high-resolution version of this image is available here.

Posted in Uncategorized | 6 Comments and counting