Flyby Over the South Pole

Fly over the South Pole at lunch, back to the tip of Patagonia by supper — just another day of drudgery collecting scientific data.

The second year of NASA’s Operation IceBridge is heading into its final week of research flights, which the team of scientists, pilots and flight crew began from their home base of Punta Arenas, Chile on Oct. 26. The multi-year campaign employs NASA’s DC-8 to fly multiple trips over Antarctica and its surrounding sea ice to measure the incremental changes that will help scientists make better judgments about sea level rise and the impact a warming climate is having on the mountainous, ice-bound continent. IceBridge crews have encountered rough weather and made long flights over magnificent, desolate landscapes, measuring ice sheet thickness, sea ice composition, snow cover and even the bedrock far underneath the icy cover. With these multiple flights and with multiple instruments on the plane, the mission is partly designed to do the work of a satellite.

The past few decades in Earth science are often referred to as the “satellite era.” Scientists’ ability to monitor so many aspects of the planet from constantly orbiting radars, spectrometers, radiometers, imagers and lidars revolutionized the way Earth’s systems could be observed. One of the most significant changes was that satellites offered consistent, global measurements over years and years — they provide continuity. NASA’s ICESat (Ice, Cloud, land and Elevation Satellite) mission was making important observations of the planet’s rapidly changing poles from 2003 until 2010, when the payload shut down. ICESat II isn’t set to launch until 2015, creating a potentially significant five-year gap in measurements. At a time when scientists pursue every change in glaciers and ice sheets with necessary urgency, that was unacceptable, and where IceBridge came in.

“We wanted to avoid an ‘oh my god’ moment when we came back in 2015 with IceSAT II,” said IceBridge scientist Seelye Martin, while talking to reporters on a media teleconference on Monday afternoon. Martin said the prospect of turning on ICESat II’s laser altimeter and finding that enormous changed had occurred and had gone unobserved partly drove the Ice Bridge planning. “We wanted continuity in the polar region. We didn’t want anysurprises.”

The timing of the IceBridge media day coincided with a big piece in the New York Times looking at not only what’s happening at the poles and with sea level rise, but what is happening with the scientific effort within NASA and beyond to study the poles. The satellite “gap” plays a role in that story, too:

The satellite difficulties are onesymptom of a broader problem: because no scientifically advanced countryhas made a strategic priority of studying land ice, scientists lackelementary information that they need to make sense of what ishappening.

Theydo not know the lay of the land beneath most of the world’s glaciers,including many in Greenland, in sufficient detail to calculate how fastthe ice might retreat. They have only haphazard readings of the depthand temperature of the ocean near Greenland, needed to figure out why somuch warm water seems to be attacking the ice sheet.

Theinformation problems are even more severe in Antarctica. Much of thatcontinent is colder than Greenland, and its ice sheet is believed to bemore stable, over all. But in recent years, parts of the ice sheet havestarted to flow rapidly, raising the possibility that it willdestabilize in the same way that much of the world’s other ice has.

For more on-the-ground — or up-in-the-air — reporting from IceBridge, check out the mission twitter or blog. You can also chat with Ice Bridge scientists on Thursday, Nov. 18, at 1 p.m. EST. The page will be open for question submittals about a half-hour before the chat begins.

— By Patrick Lynch, NASA’s Earth Science News Team

— photo at top courtesy Kathryn Hansen, NASA’s Earth Science News Team

Piloting Through Hurricane Earl

NASA scientists are deep into a two-month airborne hurricane research campaign known as GRIP (Genesis and Rapid Intensification Processes). GRIP is designed to put multiple aircraft, outfitted with scientific instruments, above a hurricane at the same time, allowing scientists to observe these destructive storms for longer periods than ever before. GRIP is breaking new ground by flying the unmanned Global Hawk at 60,000 feet above the surface, the first time NASA has used this drone in a hurricane field campaign.

But the NASA’s DC-8 and WB-57 planes get to a hurricane the old-fashioned way — with pilots in the cockpit. Dryden Flight Research Center DC-8 pilot Dick Ewers spoke to the media in Ft. Lauderdale, Fla., last week about what it takes and what it’s like to fly into the heart of a storm that your average pilot would try to avoid entirely. What On Earth was on hand to get some of his thoughts.

What should a first-time rider expect on a DC-8 flight through a hurricane?

It’s pretty bumpy at times, but most of the time it’s a lot of clouds. Then, as we get closer, we’ll go into some bumps and turbulence. As we break out into the eye, hopefully we’ll be able to see the sky above and all the way down to the water below. That’s very nice. All the sudden you’re out of the car wash and you’re looking down and can see what’s happening below. Normally it’s about 10 to 15 minutes of excitement per hour.

What’s the strongest Earl was when you flew through it?

At our level it was about 100 mph, but the worst part is down below. We’re above where it’s very intense. And when you’re flying in an airplane and through an airmass, and the airmass is moving at 100 mph, you don’t really notice that. But what you do notice is when you come out, the winds drops off and the airplane rises and falls based on what’s happening around it. So the plane isn’t able to be very level at times.

What’s your strategy to make sure the plane rides smoothly?

Most of the time it’s very solid. It’s bumpy but it isn’t weaving back and forth.

Even in 100 mph winds?

Oh, yeah. It goes right through it.

Is there a level of risk involved?

My job is to take the risk out of it. My job is to make sure what I do is safe and doesn’t put the scientists or the instruments at risk. My whole mission is to make sure that plane is back here tonight. Where the risk and danger is, I will take precautions and go around it and do something to avoid something where danger is involved.

How many flights did you make through Earl?

This will be the fourth and final flight. We thought it was declining yesterday, but it’s stronger this morning, so we’re going back out.

How was the view of the eye?

There are rare storms that are very crystal clear. This one had a lot of strataform in there, so there were clouds around and some clouds above us, so it wasn’t a pristine, clear blue eye. But you were able to see daylight above us and the water below us. I want to say it was 20 to 25 miles wide inside. You wouldn’t want to be in a boat down there.

— Patrick Lynch, NASA’s Earth Science News Team

Images taken by Patrick Lynch during the Sept. 2 GRIP media day in Ft. Lauderdale, Fla.

You're Getting Warmer

Have you noticed all the hot – and erratic – weather this summer?

So has NASA GISS climatologist Jim Hansen. He’s out with the draft of a new paper and popular summary that explores July’s anomalous weather. His main point:

The global average July 2010 temperature was 0.55°C warmer than climatology in the GISS analysis, which puts 2010 in practically a three way tie for third warmest July. July 1998 was the warmest in the GISS analysis, at 0.68°C.

Here’s his prediction on whether 2010 will shape up as the warmest in the GISS record:

2010 is likely, but not certain, to be the warmest year in the GISS record. However, because of the cooling effect of La Niña in the remainder of the year, there is a strong possibility that the 2005 and 2010 global temperatures will be sufficiently close that they will be practically indistinguishable.

And his take on whether the extreme weather events – such as the brutal heat wave that’s hammered Moscow – are connected to global climate change:

The location of extreme events in any particular month depends on specific weather patterns, which are unpredictable except on short time scales. The weather patterns next summer will be different than this year. It could be a cooler than average summer in Moscow in 2011…What we can say is that global warming has an effect on the probability and intensity of extreme events.

This points to the distinction that scientists are always making between weather and climate. Solar activity, El Nino or even volcanic eruptions can affect the weather and temperature over a short term. But when it comes to classifying what is happening to the climate, the trend must be clear and free of these influences. The climate “signal” must emerge from the data over the course of at least a decade.

What’s happening with the global surface temperature record fits this bill, Hansen said in the draft paper. Despite El Ninos, La Ninas, changes in the Arctic Oscillation, fluctuations in the sun’s radiance, snowy winters and cool summers, hot summers and warm winters, the continued trend of the average global surface temperature remains on an upward climb.

To learn more about NASA’s surface temperature record, visit this temperature update from earlier this year. Also, you can visit GISS’s technical page for detailed information about GISS’s surface temperature record.

— By Patrick Lynch and Adam Voiland, NASA’s Earth Science News Team

–The map at top was created by NASA’s Earth Observatory using data from MODIS 

Reading the Sky

Recently, a colleague and I caught a glimpse of an odd-looking contrail stretching across the sky. As we stood there and studied it, my colleague made in interesting observation.

“That’s the trail from a rocket launch,” he said. He was referring to a launch from NASA’s Wallops Flight Facility, which is about 70 miles northeast of our location at NASA Langley in Hampton, Va.

A contrail is formed when hot, humid air from exhaust mixes with cold, dryer air at high altitudes. The condensation trail forms a cloud that shows the passage of the aircraft (or, in this case, a spacecraft). Contrails can change and move easily, and by studying them we can determine how they affect Earth’s energy budget.

It can be hard to read the sky correctly because the curvature of the Earth produces some confusing optical effects. In this case, our ground perspective about 70 miles from the launch made the trail appear at first as a regular contrail crossing the sky horizontally.

But as I continued to watch, it became clear that this was no ordinary contrail. Rather than continuing across the sky, the trail clearly became higher and higher until it vanished entirely as the rocket left the bulk of the atmosphere behind.

Aside from that high arc, this trail had some other odd features. Unlike a typical contrail, which is usually pretty smooth, this one looked narrow and wiggly. Those wiggles, I discovered, were the result of adjustments in the pointing of the rocket as it zoomed through the atmosphere. This is apparent in the video of the launch.

The winds were relatively light that evening, so about 45 minutes later the trail was still clearly visible overhead. However, there was just enough wind to twist the contrail into something that could have been left behind by a crazed aerobatic pilot.

I searched the web and found the picture on the left from a Shuttle launch, which gives you some idea of what we saw.

From my point of view on the ground, there was nothing to tell me that those loops weren’t a horizontal set of circles made by a plane flying at a constant altitude. But since I knew that a rocket had left the trail, I could correctly interpret them as a spiral up to higher levels of the atmosphere.

While this experience is an extreme example, it points out the perspective problems at work whenever we look up at the sky.

Nonetheless, our Earthly perspective is valuable to learning more about clouds’ behavior, and with the help of satellites, we can get a little closer to understanding how clouds affect our climate system.

— By Dr. Lin Chambers, NASA Langley Research Center

— Top photo courtesy of Allen Kilgore, NASA Langley Research Center

How to Work at NASA Without Working for NASA

Ron Cohen, Anne Thompson and Ed Zipser all have two things in common: All three are playing important roles in NASA research campaigns, and none of them work for NASA.

NASA is one of the world’s largest Earth science research institutions, but it didn’t achieve that status solely through the work of its own employees. Instead, NASA’s Earth science field campaigns and satellite missions are constructed so that the agency can tap the best person – whether a university professor, a NASA staffer, or a scientist in another government agency – for any specific job.

The result is a grassroots approach that focuses on what the community thinks is the most important science, rather than a top-down approach.

Take Cohen, head of the Atmospheric Sciences Center at University of California (Berkeley). NASA can gain access to his expertise, and Cohen can work on large-scale research campaigns that a single university likely wouldn’t have the resources to conduct.

“The NASA facilities are really first-class,” Cohen said. “Being able to take advantage of the NASA aircraft to reach rarely studied places in the world is unrivaled. Bringing together the best people from the scientific community allows us all to work much more effectively than if we were try to do it alone.”

Cohen is working on a new “venture class” campaign called DISCOVER-AQ, which is focused on improving satellite measurement of air quality at the Earth’s surface. But his history with NASA goes back 20 years, and includes work on the Ozone Monitoring Instrument (OMI) on the Aura satellite and other aircraft campaigns.

Thompson, a professor of meteorology at Penn State, is also working on DISCOVER-AQ. Penn State’s NATIVE — Nittany Atmospheric Trailer and Integrated Validation Experiment — has been stationed at Langley Research Center the past two summers to measure a variety of air quality parameters, and has been deployed as far as Yellowknife, Canada, near the Arctic Circle, for the ARCTAS field campaign in 2008. Thompson joined the Penn State faculty five years ago, after an 18-year career at Goddard Space Flight Center.

Working with NASA keeps Thompson and her students engaged with the global science community. Getting her students in the field to make regular measurements helps them understand the importance of sustained observations of the environment.

“I want them to be able to think about working for NASA, either directly or for a contractor,” Thompson said. “It’s real work, real training. It gets young fresh faces into NASA. The synergism is very important.”

Zipser, a hurricane expert at the University of Utah, is taking part this summer in his 10th NASA field campaign since 1993. As one of the leaders of the Genesis and Rapid Intensification Processes (GRIP) experiment, Zipser is helping develop the flight plans for multiple aircraft that will fly over tropical storms as they develop.

“Working with NASA has given me, my students, and colleagues a broader knowledge base, a broader group of experts to work with,” Zipser said. “And I’ve been able to give a little back to NASA and use my horse-sense of storms to develop flight plans.”

Patrick Lynch, NASA’s Earth Science News Team

–Penn State researchers release an ozonesonde at Langley Research Center (top, courtesy of Sean Smith, LaRC); forest fire near Yellowknife, Canada (bottom, courtesy NASA).

Extreme Field Campaign

A team from NASA Langley Research Center needed a high and dry place to run their Far Infrared Spectroscopy of the Troposphere (FIRST) instrument last summer and fall. They found it in Chile’s Atacama Desert. Photo courtesy of Rich Cageao, NASA Langley Research Center.

How does a group of NASA scientists end up on a barren mountaintop, a hemisphere away from home, 17,500 feet above sea level, and in need of supplemental oxygen to stay focused in the thin air? Like most things in science, this trek began with a question or two.

“The first question is: what is the science that’s important to do? The second is: how do you do it?”

Rich Cageao said it was these questions that led a group of scientists and engineers from NASA’s Langley Research Center to embark on a four-month field campaign to the Atacama Desert of Chile in 2009, from late July to early November.

To study how water vapor absorbs infrared radiation in the high atmosphere and influences the climate, the group needed a site well above sea level. Otherwise, the higher levels of water vapor near the surface would block any attempt at detailed infrared measurements, like putting a thick layer of gauze in front of a camera lens.

A modified shipping container – like the ones shipped on rail cars and tractor trailers – became a remote office for the scientists and home for their instrument called FIRST – Far Infrared Spectroscopy of the Troposphere). Trucks took it from Virginia to California; a ship took it from California to Chile; a truck again took it from sea level to an elevation equal to the base camp on Mt. Everest. And the container – outfitted with windows, a door, an opening for measurements, and oxygen – made it to and from the site in pretty good shape, despite a few snowstorms and gale-force winds.

Here the site is seen prior to grading and preparation. Photo courtesy of Rich Cageao, NASA Langley Research Center.

Once the container was in place at a graded site on a Chilean mountain called Cerro Toco, the team set to working out the kinks with the instrument and power supply. They also worked on adapting to the daily climb from base camp at 8,000 feet to the work site at 17,500 feet.

The conditions kept everyone on their toes, and nothing ever seemed routine, Cageao said. “Warm days, out of the wind, were zero degrees Centigrade. Winds were typically 25 mph, and up to 60 mph,” Cageao described the days as extremely taxing. Nothing could be called drudgery. The possibility that something could go wrong required a state of hyper-awareness. “You’re not waiting for something to happen. You never sit around.”

After site work, the instrument, housed in a converted shipping container, was put in place in Chile following a
months-long trek by truck and ship.
Photo courtesy of Rich Cageao, NASA Langley Research Center.

But even with the cold, the wind, and the barren, almost lifeless site, Cageao couldn’t pass on the opportunity.

“We have, by nature, that feeling of, ‘we’ve got to get out there,’” he said of many scientists in the office. “We’re much happier in the field. It’s an adventure. It’s good science and it’s challenging.”

So why go to all this effort?

The Earth’s surface emits infrared radiation it has absorbed from the sun. Greenhouse gases partly trap that energy as heat, keeping the planet habitable. But with humans burning fossil fuels and altering the balance of greenhouse gases – and therefore the amount of heat trapped in the atmosphere – scientists need to understand exactly how this process works in order to improve predictions of climate change.

“The primary greenhouse gas on Earth is not CO2. It’s not methane. It’s water vapor,” Cageao said. “And when you drive up the temperature of the atmosphere, you drive up the water vapor, so you better have this right. Having it pretty close isn’t enough.”

— Patrick Lynch, NASA’s Earth Science News Team

Working (Very) Remotely

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Bryan Fabbri, Fred Denn, and Bob Arduini typically drive to their jobs at NASA’s Langley Research Center in Hampton, Va. But then there are a few days each month when they take the helicopter instead.

The three scientists are part of the small, hands-on team that maintains a suite of meteorological and climate-observing instruments on the Chesapeake Light, a platform lighthouse 15 miles off the Virginia coast in the Atlantic Ocean.

The instruments record air and sea surface temperature, the amount of sunlight and heat absorbed and reflected by the ocean surface, wind speed, aerosol composition, and on and on. The measurements are made to validate the observations made by the Langley-managed Clouds and the Earth’s Radiant Energy System (CERES).

The CERES satellite instruments have been operating for more than a decade, creating a long-term record of a key driver of Earth’s climate – the balance of incoming and outgoing solar radiation known as the “energy budget.” And the instruments that Fabbri, Denn and Arduini maintain on Chesapeake Light serve to validate the observations CERES makes over the oceans. The project is called COVE (CERES Ocean Validation Experiment) and began along with CERES more than a decade ago.

In a job that usually demands a lot of time crunching data in front of a computer screen, the regular trips to the lighthouse offer a chance for something different. They also highlight a side of science that isn’t often discussed: the grunt work of making sure your instruments are working properly…or haven’t corroded in the humid salt-air…or haven’t blown off the platform with an open-ocean gust. If the sensors aren’t working properly, CERES observations over the ocean would be much more difficult to validate.

It doesn’t hurt that this important work means getting out in the middle of the ocean every now and then.

“You can’t beat that part of it,” Fabbri said. “I get a little stir crazy. I like getting out of the office and out there to work on the instruments. It doesn’t hurt to take the helicopter out.”

— By Patrick Lynch, NASA’s Langley Research Center

Revisiting the Iris Effect

A surprising paper published last summer suggested that a cloud-related feedback called the Iris Effect might counteract much of the warming associated with man-made greenhouse gases. NASA Langley’s Takmeng Wong (below) was one of several climate scientists who responded to the paper with a methodical inspection of its methods. Credit: Photograph STS109-325-2/Johnson Space Flight Center

A study published last summer by MIT’s Richard Lindzen and Yong-Sang Choi showed a curious thing: 15 years of observations of the tropics revealed that the Earth responds to rising sea surface temperatures by dumping more radiation to space. According to the authors, this feedback — dubbed the “iris effect” — would prevent much of the expected warming due to man-made greenhouse gas emissions. Further, Lindzen and Choi suggested that 11 major climate models had gotten this effect wrong. The paper found the Earth’s climate not nearly as sensitive to global warming as commonly thought.

A number of scientists, at NASA and elsewhere, immediately wondered how they could have missed such a major discrepancy between models and real-world observations. Their response to the paper provides an example of the back-and-forth, checking and re-checking that makes up the scientific process.

NASA Langley’s Takmeng Wong was one of the scientists surprised by the Lindzen and Choi paper. Wong works with data from the Clouds and the Earth’s Radiant Energy System (CERES) on NASA’s Terra satellite and from the Earth Radiation Budget Experiment (ERBE) satellite. Lindzen and Choi used ERBE data for their analysis, so Wong was naturally interested.

“When you see a surprising result, the first thing you do is go to the paper and see what they have,” Wong said. “We tried to do that and to reproduce their results. It’s part of the scientific process.” Being able to reproduce a specific result is an important building block of scientific knowledge.

Wong and Colorado State University’s Chris O’Dell eventually teamed up with Kevin Trenberth and John Fasullo, climate scientists at the National Center for Atmospheric Research, to publish a response. Their examination uncovered a number of deficiencies in Lindzen and Choi’s method, and found their result to be unstable and fragile. That analysis appeared this month in Geophysical Research Letters.

“We went to the same model data, to see if the observations are going one way and the models are going the other way,” Wong said. “When the analysis is done properly using robust scientific technique, what you find is that the observations and the models are consistent to within the uncertainty of the data.”

Wong summarized a few basic problems that led to the surprising finding: 

1. Lindzen and Choi focused on a number of selective time periods. But if the beginning and end points of those time periods are adjusted only slightly, their result falls apart.

2. The paper also treated the tropics as a closed system. In other words, it did not take into account any outside influences on what was happening in the tropics, such as the large amount of energy transport moving in and out of the tropics on ocean currents and atmospheric waves during events such as El Nino and La Nina.“The tropics is not a closed system,” Wong said. “But they treated it as such in the study.”

3. Lindzen and Choi took their result from the tropics and applied it globally, instead of using global data to study the link between global temperature increases and global outgoing radiation to space.

When questions arise that run counter to prevailing thought, Wong said, the only thing to do is take a closer look.

“You cannot make a scientific judgment,” Wong said, “until you’ve done the complete analysis.

Read more about the Iris Effect at the
NASA Earth Observatory

–Patrick Lynch, NASA’s Earth Science News Team

Communicating Climate Change

Rigor. Not rigor mortis.

Those are two basic tenets of talking to the public about global warming, offered by Mark Serreze, director of the National Snow and Ice Data Center. He spoke at a Thursday morning session on “communicating climate” at the American Geophysical Union’s fall meeting in San Francisco.

The climate debate as carried out on cable news, over dinner tables and at the office these days is anything but dead. Serreze and a handful of other presenters at the session encouraged scientists to inject their scientific knowledge into this debate, especially at this critical moment for policy development to address climate change impacts. But, Serreze gently prodded, be sure to bring the scientific rigor, while leaving the calcified sciencese in the lab.

In past years a session like this might not have even appeared on the AGU schedule. No data-dense graphs were shown, no recent breakthroughs discussed. But its presence on the agenda – and a strong attendance – say something about the pitch and significance of the public climate debate right now.

Michael Mann, a Penn State climate scientist respected worldwide who, with colleagues, produced the now-famous “hockey stick” graph depicting recent drastic temperature changes, led off the session. Mann (pictured) has become a target of climate change deniers. Some of his personal emails were among those aired after hackers stole them off a computer server at the University of East Anglia Climatic Research Unit in England recently.

Mann said scientists for too long have been content to focus on their science and let any public debate of it play out on its own. He contends this strategy isn’t enough anymore, as a “well-funded disinformation effort” is still hard at work to discredit climate science and confuse the public.

“We’ve got to be out there, making the case,” Mann said. “These allegations are a distraction and are specious. We have to say that and at the same time use the opportunity to make the positive case.”

“The media alone cannot be expected to adequately defend the science and the scientists. It’s not their job. Our job is to make sure scientific truth is represented,” Mann said.

— Patrick Lynch, NASA’s Earth Science News Team
   Image Credit: Penn State University