Coming to ACT-America

A side-by-side flight for NASA’s C-130 and Langley Research Center’s UC-12 over Farmville, Virginia. By measuring the same air from two aircraft, instruments on both aircraft can be tuned to yield the same output. Credit: Anke Roiger

by Julian Kostinek / WALLOPS FLIGHT FACILITY, WALLOPS ISLAND, VIRGINIA /

One year after starting my Ph.D. studies at the DLR (German Aerospace Center), which involves spending hours and hours week after week in labs optimizing a Quantum Cascade Laser Spectrometer (QCLS) for airborne greenhouse gas analysis, the time has finally come to get out into the wild.

When Ken Davis from Penn State University visited DLR at the end of 2016, a big and thrilling chance opened up to take part in one of NASA’s big atmospheric science missions: Atmospheric Carbon and Transport-America (ACT-America). Davis is the principal investigator.

ACT-America is a project aimed at better understanding how mid-latitude weather systems interact with carbon dioxide and methane sources and sinks. By measuring these significant greenhouse gases from aboard NASA Wallops Flight Facility’s C-130 and Langley Research Center’s B-200 aircraft, both equipped with high performance instrumentation, better data on regional carbon dioxide and methane sources and sinks will become available to scientists all across the world.

Arriving last month at Wallops Flight Facility in Wallops Island, Virginia, we (my colleague Anke Roiger and I) got a quick tour through Hangar N-159 with Martin Nowicki, system engineer at Wallops. Martin and all the other folks  at Wallops helped us big time during the upload phase.

At first, we were totally overwhelmed by how big everything was here at NASA, especially the C-130. It’s enormous, at least to us, because we normally operate on much smaller aircraft. For the following two weeks the C-130 Hercules was prepared by the engineers and mechanics of the maintenance crew at Wallops.

NASA’s WFF C-130 on the maneuvering area, just outside of Hangar N-159 at Wallops Flight Facility, during mission preparation. Scientists can power up their instruments hours before takeoff, to allow the delicate instruments to reach stable conditions. Credit: Julian Kostinek

Under the lead of ACT-America program manager Mike Obland from NASA Langley and C-130 Integration/Operations Engineer Linda Thompson from Wallops, all instrument racks had been mounted one after the other. Unfortunately, our rack didn’t reach Wallops because of problems with our logistics company, which caused a real headache.

But here at NASA, people find a solution for every problem: James “Jimmy” Geiger from Langley helped us out with an empty, brand-new C-130 rack. He even designed an inlet probe for our instrument, enabling sampling of atmospheric air just outside the aircraft’s boundary layer. With our stuff arriving at Wallops we could finally move on to installing the instrument.

On Sept. 22 the mission transitioned from the upload phase to the operational phase. The science teams were now meeting at Wallops for calibration, planning and the last tests of their respective instruments. Suddenly the hangar became crowded.

Sept. 24 was the big day I had been looking forward to for so long: The first instrument test flight and my first ever flight on a C-130. I was totally excited. With the turboprop engines starting up, one can really feel the power behind this aircraft. Although way louder, it takes off and lands as smoothly as big passenger aircraft. Or is it just because of the pilots?

PhD student Julian Kostinek flies on NASA’s C-130 aircraft. Credit: NASA

I had been expecting a rough ride in advance, but the plane was surprisingly stable and calm. The QCLS instrument had a stable performance too—what a nice surprise! Some minor issues existed, but all parameters remained in a safe-to-operate domain at all times. The first flight had been a complete success with respect to our instrument. The same held for the other teams too, according to the post-flight meeting. These meetings, known as de-briefings, are held on a regular basis after each flight. All personnel aboard the aircraft attend these, including the pilots.

The flight for the B-200 wasn’t quite as successful as the C-130’s. The crew found issues with a PICARRO greenhouse gas analyzer. Decisions were made to remove an identical instrument from the C-130 and mount it on the B-200.

With a spare PICARRO instrument mounted in virtually no time by the AVOCET team, the second instrument test flight could be engaged. An in-air rendezvous, or side-by-side flight, with Langley’s B-200 aircraft was planned and successfully carried out, along with LIDAR calibration at different altitudes, to pave the way for the upcoming science flights. The side-by-side flight enables comparison between the instruments mounted on the two aircraft. By measuring the same air on both aircraft, data integrity can be greatly improved. Another awesome flight for all of us.

With the test flights successfully carried out, time has come for the real deal: the scientific flights. But more on that later, gotta hop on to the next flight. See y’all! And thanks NASA for enabling this unique experience.

Bullseye! The Hunt for Open Arctic Water

by Carol Rasmussen / KEFLAVIK, ICELAND /

The Oceans Melting Greenland science team carefully planned each location for the team to drop its ocean probes. Some sites are in narrow fjords; others are hundreds of miles out on the continental shelf. Each site was chosen to add value to the data the team is collecting.

The two biggest enemies of this planning are ice and weather.

Sea ice is at its lowest at this time of year, but there’s plenty of it around Greenland, especially in the north. The probes can’t punch through it to reach the water below. If a drop site is ice covered, the team looks for a location that is “close by and second best,” said principal investigator Josh Willis.  They might need to go to the next fjord over or a bit farther out on the shelf. Since no data whatsoever have been collected from much of the northern coastline, these alternatives have value too.

A perfect drop site, viewed through the tube where the ocean probes are dropped. Credit: NASA/Charlie Marshik
A perfect drop site, viewed through the tube where the ocean probes are dropped. Credit: NASA/Charlie Marshik
Ice in northern Greenland led to some frustrating days for probe drops. This fjord almost completely choked by ice was one of the unsuccessful probe drop sites, shown as orange pins on the map (below). Green pins indicate successful drops. Credit: NASA/JPL-Caltech
Ice in northern Greenland led to some frustrating days for probe drops. This fjord almost completely choked by ice was one of the unsuccessful probe drop sites, shown as orange pins on the map (below). Green pins indicate successful drops. Credit: NASA/JPL-Caltech

_OMG_Josh Willis_Svarbard-Norway_ Orange NoGo-Green Go IMG_7690

Project manager Steve Dinardo has been working on airborne projects for 38 years. “Weather is always the problem. When you don’t want clouds, you get clouds. When you want clouds, you don’t get them,” he said.

OMG doesn’t want clouds. If the team can’t see the ocean, they can’t risk hitting a ship or whale by blindly dropping a probe. “We’re always looking for places where we can get a lot of work done in a short period of time,” Willis said. “If we fly in a region where the clouds are low and we can’t see the water through them, those can be really frustrating days.”

Turbulence can be a problem as well. To prepare and drop the probes, team members have to move around the cabin, not sit with the seatbelts securely fastened like commercial airline passengers.

It's not possible to drop probes in cloud cover like this. Credit: NASA/JPL-Caltech
It’s not possible to drop probes in cloud cover like this. Credit: NASA/JPL-Caltech

On the windy flight of Oct. 1, Dinardo was sitting at the computer to read the probe data.  “We were getting pretty hammered in the back,” he said. “Between me vibrating up and down and the keyboard vibrating up and down, I hit a number-lock key on the keyboard. The computer froze and I had to reboot it.” Despite that mishap, it was a successful day, with 14 probes dropped and returning signals.

Over the weeks of the mission, the team has gained skill at hitting small targets, Willis said. “We got really lucky one day when we were operating out of Svalbard, Norway. On a day when we were particularly frustrated by ice, we found a gigantic iceberg pushing through a huge area of sea ice, leaving a small wake behind it. The team amazingly bullseye’d the wake, dropping an ocean probe right through the water on the backside of the iceberg. It was a shining moment when the team showed we could hit a very small target from an aircraft traveling 200 knots.”

Flight engineer Terry Lee prepares to drop a probe. Credit: NASA
Flight engineer Terry Lee prepares to drop a probe. Credit: NASA

Today, however, weather is keeping the team on the ground. For several days, Dinardo and senior pilot Bill Ehrenstrom have been watching a forecast storm approach from the south. Today, it finally arrived. The crew was grounded by clouds and gusty winds over Greenland. Tomorrow doesn’t look any better, with the forecast calling for gusts up to 55 miles per hour.

“I think we have at least one more day before we have any chance of flying,” Ehrenstrom said, though he won’t make the final call till tomorrow morning.

 

 

Taking the Ocean’s Temperature Around Greenland

by Carol Rasmussen / KEFLAVIK, ICELAND /

SCENIC

Over the last three weeks, the Oceans Melting Greenland team has spent many hours flying over spectacular Arctic scenery. Fjords, glaciers, icebergs, the northern lights — they’ve seen enough sights to fill a guidebook. But the most compelling view, the view they came all the way north to see, is on a computer screen inside the plane.

OMG is in the field this fall to do one thing 250 times: drop ocean probes from an airplane around the entire coast of Greenland and read its measurements of ocean temperature and salinity. Relayed to the airborne computer, the data from the probes shows where warm, highly salty, subsurface Atlantic water is able to reach the bottoms of glaciers along the coast.

The computer on NASA's G-III aircraft shows an ocean probe's measurements as it sinks through the water near the Greenland coast. The water is warmest and saltiest near the surface.
The computer on NASA’s G-III aircraft shows an ocean probe’s measurements as it sinks through the water near the Greenland coast. The water is warmest and saltiest near the surface.

This water is warm only in comparison with the polar runoff that forms the surface layer, but its extra 6-8 degrees Fahrenheit (3-4 degrees C) makes it plenty warm enough to melt glacial ice. The polar water can be as cold as 4 degrees below freezing Fahrenheit (-2 degrees C). At those temperatures it doesn’t melt ice at all.

On 13 research flights since Sept. 13, the team has dropped 163 of the probes around all of Greenland except the southeast coast. They’ll pepper that coastline with the remaining probes from their new location in Keflavik, Iceland.

Flight engineers Phil Vaughn and Terry Lee (NASA Johnson Spaceflight Center) drop a probe on target. Credit: NASA
Flight engineers Phil Vaughn and Terry Lee (NASA Johnson Spaceflight Center) drop a probe on target. Credit: NASA

In the last year or two, various research teams have done seafloor surveys of a few Greenland glaciers and found deep gashes on the edge of the continental shelf where subsurface warm water can creep up on the shelf and melt the glaciers more quickly than the colder shallower water. But these few locations to the whole coastline would be risky business. Willis says that when they began the survey in mid-September, “I didn’t know what to expect. We knew that Atlantic water was getting into a few of these fjords, but the shelf has not been measured extensively before, and satellite data won’t tell you if warm, salty Atlantic water is there because it’s so far below the surface. You have to go drop a temperature sensor in the water.”

The probes relay their measurements in real time to the airborne computer, so the OMG team got views of subsurface conditions starting with the very first drop. As the measurements kept rolling in, the view from the computer screen became more and more disturbing.

OMG project manager Steve Dinardo (NASA Jet Propulsion Laboratory) at the airborne computer that collects the probe data. Credit: NASA
OMG project manager Steve Dinardo (NASA Jet Propulsion Laboratory) at the airborne computer that collects the probe data. Credit: NASA

“Very soon, it became clear that there was a good deal of warm water on the shelf — not just in the fjords but spread out. As we mapped farther and farther north, we could see more warm water on the shelf. Now we’ve sampled [most of] the continental shelf, and everywhere that it’s deep enough, there seems to be Atlantic water present,” Willis said.

It’s unlikely that the southeast section will contain surprises, he added, because scientists already know that glaciers in this sector are melting very quickly and ocean warming is evident on the surface.

Willis emphasizes this is only a first impression from watching the data on screen. However, he pointed out, “Every time we make a discovery about ice melt in Greenland, we find the picture is worse than we thought it was before. I don’t think this will be any exception.”

AN ARCTIC PORFOLIO

Crew members of NASA’s Oceans Melting Greenland mission have seen extraordinary sights during their latest deployment, both from the plane and at their four bases. Here are a few highlights.

 

Solo Science Flying at 65,000 Feet

by Ellen Gray / WALVIS BAY, NAMIBIA /

Stu Broce loves flying high.

“The view is incredible. You can see 300 miles away,” he said from the cockpit of NASA’s high-altitude ER-2 research aircraft. “You can see the curvature of the Earth. If you look up, the sky is very dark blue.”

Of course, for the ORACLES mission now in Namibia studying low-level clouds and aerosols over the south-east Atlantic Ocean, the view of never-ending white is not going to be quite so exciting for the pilots, he added with a grin. There’s more to flying high than the view.

Pilot Stu Broce in the cockpit of the ER-2. On a flight day he’ll be wearing a spacesuit to protect him from low pressures at high altitude. Credit: NASA/Jane Peterson
Pilot Stu Broce in the cockpit of the ER-2. On a flight day he’ll be wearing a spacesuit to protect him from low pressures at high altitude. Credit: NASA/Jane Peterson

“I kind of like the solitude, too. It’s my happy place. No matter what’s going on in my life, when I close the canopy, and especially when I leave the ground, I know I’ve got 12 hours of alone time. Busy alone time,” Broce said.

A retired Navy pilot, Broce flew commercial for nearly a year before post-9/11 furloughs led him back to the military, this time the Air Force, where he learned to fly the high altitude aircraft. As luck would have it, around the time he was retiring, NASA was hiring, and Broce has been flying the ER-2, as well as other aircraft, for NASA for the last five years at Armstrong Flight Research Center in California. He’s one of two pilots flying the ER-2 for the ORACLES mission this month.

NASA’s ER-2 lands at Walvis Bay Airport, Namibia. Behind it is the chase car driven by the second ER-2 pilot with a radio to be an extra pair of eyes for landing. Credit: NASA/Brian Rheingans
NASA’s ER-2 lands at Walvis Bay Airport, Namibia. Behind it is the chase car driven by the second ER-2 pilot with a radio to be an extra pair of eyes for landing. Credit: NASA/Brian Rheingans

It’s a challenging aircraft to fly. Landing in particular. “It’s like landing a big 30,000 pound bicycle,” he said. The ER-2’s two main sets of wheels are under the body. The wheels that prop up the wings on the ground drop off during take-off and don’t fly.

The ER-2 is a small, lightweight airplane with a single occupant: the pilot. Its job is to get the long view of the clouds below. Tucked into its nose, body and a pod under each wing, the ER-2 carries four remote-sensing instruments to 65,000 feet, twice the altitude of commercial airliners.

“The only people higher than us are the astronauts in the space station,” said Broce. “We fly so high, we fly above Armstrong’s line at 60 to 62,000 feet, where if you took a cup of water at altitude outside the plane, the water would boil just because of the low pressure there, even though it’s super cold.”

People don’t do so well at those low pressures. The pilots wear space suits that will pressurize in case of a loss of cabin pressure. Part of their prep is to breathe pure oxygen for an hour before flight to purge the nitrogen from their bodies so they don’t get the bends when they ascend so quickly. Food and water for the eight plus hours in flight both come through a tube – applesauce, pear-sauce, and peach-sauce are among Broce’s favorites, which he said are actually pretty good.

The ER-2 in the hangar at Walvis Bay Airport. The pod under the visible wing is open where a science instrument is installed. Credit: NASA/Jane Peterson
The ER-2 in the hangar at Walvis Bay Airport. The pod under the visible wing is open where a science instrument is installed. Credit: NASA/Jane Peterson

The instruments, on the other hand, do great at 12 miles above the Earth. While they’re not as high as satellites, some of the instruments simulate satellite measurements. Aboard the ER-2 they both test out new technology and software and get the equivalent of satellite data right where the scientists want it.

The science team is trying to understand the interaction of clouds and tiny airborne particles – smoke from fires central Africa – and how they change the amount of energy absorbed or reflected from the clouds, a key component for assessing how clouds affect Earth’s climate.

Brian Cairns of Goddard’s Institute for Space Studies works on the Aerosol Polarimetry Sensor in the pod under the ER-2 wing. Credit: NASA/Jane Peterson
Brian Cairns of Goddard’s Institute for Space Studies works on the Aerosol Polarimetry Sensor in the pod under the ER-2 wing. Credit: NASA/Jane Peterson

Broce helps out with gathering the data. The instruments are as fully automated as can be, but he still needs to turn them on after take-off and sometimes during flight switch their modes.

“I like to count the number of button presses per hour. It’s ‘BPH’ — my term. If it’s above ten, I consider that busy because you have to read checklists and know when to hit the button and check miles and time and locations. We also have to navigate and fly the plane, sometimes to precise navigation or headings, and then push the buttons.”

At the end of the day, the goal is to return measurements to scientists waiting on the ground.

For more on Broce’s work as ER-2 pilot for ORACLES, visit Notes From the Field: ORACLES in Namibia 2016.

(Note: This wraps up our reporting from Namibia. Click here for all the ORACLES blog reports.)

 

 

Into Africa Seeking the Desert Sun

by Ellen Gray / GOBABEB, NAMIBIA /

Brent Holben stands in the shade of his car’s hatchback door, squinting at his phone. He’s checking Google Maps. From the dirt parking lot at the Walvis Bay Airport, Namibia, he temporarily has free internet access to the NASA wifi hotspot set up for NASA’s ORACLES airborne science campaign here.

“I don’t want to make a wrong turn,” he says. “Of course out here, that’s pretty hard. There’s not many turns.”

Gobabeb Research and Training Centre in Namibia. Credit: NASA/Jane Peterson
Gobabeb Research and Training Centre in Namibia. Credit: NASA/Jane Peterson

With a trim gray beard and brimmed hat, Holben, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is in charge of the ground sites that will measure aerosols to complement observations made by ORACLES’s two research aircraft.

Today, Holben is heading out on a road trip southeast of Walvis Bay to the Gobabeb Research and Training Centre, 40 miles as the crow flies from the coast. There, perched atop a short tower, is one of Holben’s aerosol measuring instruments, a sun photometer that is part of the Aerosol Robotic Network. AERONET, which began in 1992 with two sensors, now has 600 sensors worldwide, but not as many in Africa as Holben would like.

Brent Holben, project scientist for the Aerosol Robotic Network (AERONET) from NASA’s Goddard Space Flight Center. Credit: NASA/Jane Peterson
Brent Holben, project scientist for the Aerosol Robotic Network (AERONET) from NASA’s Goddard Space Flight Center. Credit: NASA/Jane Peterson

“Africa is a giant place, and it’s underrepresented compared to Europe and the United States.” Holben is the AERONET project scientist.

As ORACLES was being planned to make measurements of aerosols over the southeast Atlantic Ocean from aircraft, he originally drafted plans for two AERONET instruments in Namibia that would study aerosols from the ground. He ended up setting up ten.

A sun photometer has one job: to look at the sun to see how many aerosols are between it and the ground by measuring the light energy that reaches the instrument.

The AERONET sun photometer at Gobabeb points at the sun and measures the light energy that reaches it. Since scientists know how much energy the sun produces at the top of the atmosphere, any difference measured by the instrument at the ground is caused by "stuff" – aerosols like smoke, dust, and sea salt – between the top of the atmosphere and the ground. From that scientists can calculate aerosol concentrations in the atmosphere. Credit: NASA/Jane Peterson
The AERONET sun photometer at Gobabeb points at the sun and measures the light energy that reaches it. Since scientists know how much energy the sun produces at the top of the atmosphere, any difference measured by the instrument at the ground is caused by “stuff” – aerosols like smoke, dust, and sea salt – between the top of the atmosphere and the ground. From that scientists can calculate aerosol concentrations in the atmosphere. Credit: NASA/Jane Peterson

“If the set-up weren’t simple, I wouldn’t do it,” Holben said of the solar-powered instrument.

But simple doesn’t mean without complications. One reason Holben is visiting Gobabeb is because he’s concerned about the instrument shutting down unnecessarily due to the region’s characteristic fog.

The sky is overcast on our drive south, which is not uncommon along the Namibian coast. Early morning fog develops when warm air condenses over the cold ocean water, and then it rolls over the length of the coast and inland. It’s the main source of water for much of the vegetation that grows where it can across the plain.

Not far from the airport the asphalt disappears and we’re driving on a dirt road. To either side the rocky desert is white-beige and flat, textured with small rocks and dotted with occasional buildings that grow fewer and farther between.

On the horizon ahead, great sand dunes appear, first as bumps, then looking like orange mountains. Eventually, a green strip comes into view at the base of the dunes. Holben points out as the green strip resolves into trees. “That’s the river.”

The river is the Kuiseb (pronounced kwee-sib), and it’s dry for most of the year.  During the rainy season from November to January or so, it may have water for a few months, replenishing the groundwater for the trees – and everything that eats their leaves – to live on for the rest of the year.

The road turns east and from here parallels the river into the Namib-Naukluft Park and to Gobabeb Centre where it dead-ends. Along the way are the farms of the local Topnaar community, which has lived along the Kuiseb for the past 600 years. Many have day jobs in Walvis Bay to supplement their living. Along the river they raise cattle and other livestock.

House in the desert near the Kuiseb River. Credit: NASA/Jane Peterson
House in the desert near the Kuiseb River. Credit: NASA/Jane Peterson

“It’s a harsh existence. You’ve got to admire people who eke out a living here,” said Gillian Maggs-Kölling, the Gobabeb Centre’s executive director. The centre is located next to three ecosystems: the rocky plain, the linear oasis of the river, and the 1,000-foot sand dunes that roll into the Sand Sea to the south.

Maggs-Kölling is a biologist, as are most of the 18 researchers and students who live and work there. It’s an international mix, with students from the Namibian University of Science and Technology joined currently by a group from the University of Basel in Switzerland, and a handful of others from various other European and American universities.

The main building with labs and offices is surrounded by a spread of low cottages and gardens of scientific instruments measuring temperature, moisture, and a dozen other things. Completely off-grid, the site is powered by solar panels with the occasional help of a generator.

This is Holben’s third trip to Gobabeb, one each year since setting up the AERONET sensor here.

“We came here because we didn’t have an instrument in this part of the world. The Namib Desert is quite unique because it is influenced by fog,” said Holben. He and the ORACLES team hope to learn how the aerosols they’re measuring affect the fog and the clouds over the ocean.

We meet Monja Gerber, a relatively new technician and Masters student in plant physiology from North West University in South Africa, who is taking care of the instrument this year.

Brent Holben walks Monja Gerber through maintaining the AERONET instrument at Gobabeb. Credit: NASA/Jane Peterson
Brent Holben walks Monja Gerber through maintaining the AERONET instrument at Gobabeb. Credit: NASA/Jane Peterson

Atop the two-story tower where the AERONET instrument sits, Holben shows Gerber a few maintenance tricks. The instruments tube is open and sometimes spiders or bees like to make homes in them, he points out. Holben shows her how to disconnect the wet sensor that triggers when fog collects on it.

As the day warms, morning fog that rolls in from the coast clears. Using its own GPS location and the time of day to find the sun, the AERONET photometer spins into action.

“We’re looking at two main aerosols in this region. Dust blown from the desert is one, which is actually a very small component. The big one is smoke from fires in central Africa. These are man-made agricultural fires as people clear their land at this time of year,” said Holben.

Westerly winds take the smoke from the Democratic Republic of Congo, Zambia, and Angola, and carry it out over the southeast Atlantic, where ORACLES’s two research aircraft measure it to see how the smoke changes sunlight absorption or reflection – important to know for understanding and predicting climate change. That smoke arcs back to Namibia on south-easterly winds.

“We’ve been watching the aerosols day by day for ORACLES,” Holben said of both the measurements here at Gobabeb and the six sensors that are set up in Henties Bay, an hour north of Swakopmund. “Over the last several days, the optical depth went from almost background conditions to – yesterday – moderately high.”

Light scattered by the smoke aerosols makes sunsets here red, Holben added.

The sunset is spectacular. Holben and his son Sam, who accompanied him on the trip, cross the river and climb to the top of the nearby dune to watch. They leave with barely enough time, and Sam, not wanting to miss it, runs ahead and picks the steepest ascent.

Brent Holben and his son, Sam, hiking toward the top of a dune to catch the sunset. Credit: NASA/Jane Peterson
Brent Holben and his son, Sam, hiking toward the top of a dune to catch the sunset. Credit: NASA/Jane Peterson

Climbing a dune of fine sand is not easy, and he slides down nearly as much as he climbs, but persistence gets him to the top. Holben takes a less-steep approach and settles in for the show.

From the top, the Namibian landscape stretches as far as the eye can see, changing colors as the sun sinks behind the dunes in the west. The stars slowly come out and the Southern Hemisphere constellations brilliantly shine beneath the sweep of the Milky Way.

Sunset at Gobabeb, Namibia. Credit: NASA/Jane Peterson
Sunset at Gobabeb, Namibia. Credit: NASA/Jane Peterson

 

On the ‘Positively Radiant’ Research Flight

by Ellen Gray / WALVIS BAY, NAMIBIA /

The ORACLES science team is in southern Africa to fly.

The bulk of their work is done in the narrow confines of the stocky P-3 aircraft amid racks of customized instruments. In the coming weeks these instruments will be complemented by remote sensors on the high-altitude ER-2 aircraft. But while the ER-2 team waits for the arrival of their specialized fuel, the science flight on September 2 is all P-3.

For this 8:00 a.m. flight, wake up time is early but you wouldn’t know it for the palpable sense of excitement the scientists have as they board the plane. This is the first “flight of opportunity;” the theme: It’s Positively Radiant Research. The flight will focus on the energy balance of the clouds over the ocean: how much light are clouds reflecting or absorbing as they interact with the smoke aerosols that travel from agricultural fires in central Africa.

David Noone of Oregon State and Ken Sinclair of NASA’s Goddard Institute for Space Studies are measuring the isoptopic fingerprint of water vapor that can tell them how much aerosols and clouds are mixing together. Credit: NASA/Jane Peterson
David Noone of Oregon State (left) and Ken Sinclair of NASA’s Goddard Institute for Space Studies onboard the P-3 research aircraft are measuring the isoptopic fingerprint of water vapor that can tell them how much aerosols and clouds are mixing together. Credit: NASA/Jane Peterson

The inside of the P-3 looks like a laboratory with big boxy instruments in front of airline seats. Twenty-four scientists can fly at a time with more than a dozen instruments. Once everyone’s aboard, ears safely covered by noise-cancelling headphones, the turboprop engines fire up. The P-3 taxis down the runway and takes off.

NASA’s P-3 research aircraft, ready to fly from Walvis Bay, Namibia. Credit: NASA/Jane Peterson
NASA’s P-3 research aircraft, ready to fly from Walvis Bay, Namibia. Credit: NASA/Jane Peterson
 The inside of the P-3 holds racks of science instruments and their science teams. Credit: NASA/Jane Peterson
The inside of the P-3 holds racks of science instruments and their science teams. Credit: NASA/Jane Peterson

This is a LOUD plane – deafening, in fact. The headsets have the dual role of hearing protection and allowing everyone on board to communicate, reporting real-time observations. Sebastian Schmidt of the University of Colorado, Boulder is the flight scientist  today. Sitting up front, his is the single voice speaking to the pilots, relaying any requests for adjustments in the flight path that come from the instrument teams.

The pilots, Mike Singer and Mark Russell of NASA’s Wallops Flight Facility, have final say on the flight path. They are responsible for the safety of the plane and its occupants. With hundreds of science flight hours under their belts, they’re very familiar with how scientists like to fly. Today it’s in tight spirals from the top of the smoke layer and clouds to near the ocean surface to see what the air is doing along a vertical column.

Sebastian Schmidt of the University of Colorado Boulder is the flight scientist on Sept. 2 keeping track of all activities aboard the P-3. Credit: NASA/Jane Peterson
Sebastian Schmidt of the University of Colorado Boulder is the flight scientist on Sept. 2 keeping track of all activities aboard the P-3. Credit: NASA/Jane Peterson

On this eight-hour flight, though, the science team channel isn’t all business. “Who still needs a nickname?” Sam LeBlanc of NASA’s Ames Research Center in charge of the 4STAR instrument asked at one point.

A number of the flying scientists apparently still do. Among them, Sabrina Cochrane, a second-year grad student at the University of Colorado, Boulder, manning the Solar Spectral Flux Radiometer. This is her first research flight.

“I was really nervous,” she said after the flight. “I thought I was going to feel sick the whole time with all the spirals, but I didn’t. It was really smooth. It was a lot more fun than I expected.”

 For Sabrina Cochrane of the University of Colorado Boulder, this is her first research flight. Credit: NASA/Jane Peterson
For Sabrina Cochrane of the University of Colorado Boulder, this is her first research flight. Credit: NASA/Jane Peterson

Flying between the spiral locations, the Airborne Precipitation Radar team was on the look-out for another high-flyer: the CloudSat satellite in space, which was scheduled to make a pass over the same region the P-3 was flying. This radar measures cloud droplet sizes and numbers, validating the same measurements taken from space by CloudSat’s radar.

The satellite overpass was not exactly over the flight path, but close enough, said Steve Durden of NASA’s Jet Propulsion Laboratory. “Even if they’re not perfectly aligned you’ll see the same structures in the clouds,” he said.

The final maneuvers of the day occur during the last hour of flight on the way back to Walvis Bay Airport. David Noone of Oregon State University explained that these maneuvers are for the instruments, to find out how different orientations of the aircraft affect the measurements.

P-3 pilot Mike Singer from NASA’s Wallops Flight Facility guides the aircraft through maneuvers designed to collect maximum measurements of aerosols and clouds. Credit: NASA/Jane Peterson
P-3 pilot Mike Singer from NASA’s Wallops Flight Facility guides the aircraft through maneuvers designed to collect maximum measurements of aerosols and clouds. Credit: NASA/Jane Peterson

“My measurements, the water vapor and the water vapor isotope measurements, are a good example of this. We’re bringing in air from outside through an inlet that must be pointing directly forward into the flow. If it’s slightly off, the number of cloud droplets that enter the inlet might vary,” he said.

To test out the orientations the pilots will wiggle the tail of the aircraft, roll side to side, and go up and down like they’re going over a hill.

“Now some of these are good fun,” said Noone, “but we’re sitting here in the back of the aircraft. We’re way out in the tail so we’re going to get a good ride.”

NASA’s P-3 flies above clouds over the southeast Atlantic ocean to study their interactions with smoke. Credit: NASA/Jane Peterson
NASA’s P-3 flies above clouds over the southeast Atlantic ocean to study their interactions with smoke. Credit: NASA/Jane Peterson

 

 

Andrew Dzambo from the University of Wisconsin (left) and Steve Durden from NASA’s Jet Propulsion laboratory monitor the Airborne Precipitation Radar which measures cloud droplet size aboard the P-3. Credit: NASA/Jane Peterson
Andrew Dzambo from the University of Wisconsin (left) and Steve Durden from NASA’s Jet Propulsion laboratory monitor the Airborne Precipitation Radar which measures cloud droplet size aboard the P-3. Credit: NASA/Jane Peterson

 

 

 

On the Hunt for the Perfect Science Flight

by Ellen Gray / SWAKOPMUND, NAMIBIA /

Planning a science flight does not appear to be most exciting part of a NASA airborne mission, even from an exotic location like the Namibian coast where we are now for the ORACLES mission. No planes. No high-altitude views. Just a group of people on computers sitting at long tables in a windowless conference room staring intently at a projector screen.

“I couldn’t disagree more that it’s unglamorous,” said ORACLES principal investigator Jens Redemann of NASA’s Ames Research Center. “I am so excited to be here planning the flights. It’s the promise of a great flight, like visualizing the greatest possible outcome. It’s the perfect flight that we’re on the hunt for every time. You don’t think about anything else while you’re flight planning.”

ORACLES principal investigator Jens Redemann listens intently to the forecast briefing that will be used for flight planning. Credit: NASA/Jane Peterson
ORACLES principal investigator Jens Redemann listens intently to the forecast briefing that will be used for flight planning. Credit: NASA/Jane Peterson

The work they’re doing at this 8:00 a.m. meeting literally drives the mission. The forecasting team shows videos of slow-moving model projections of the clouds and aerosols over central and southern Africa and the Atlantic Ocean all the way out to Ascension Island. Like fishermen discussing where to find the best catch, they discuss in excruciating detail where they think the best clouds and aerosol plumes will be.

Like any other prediction of the future, however, these models are not 100 percent correct all the time.

Pablo Said of the National Center for Atmospheric Research discusses details of the forecast with ORACLES principal investigator Jens Redemann during the weather briefing. Credit: NASA/Jane Peterson
Pablo Said of the National Center for Atmospheric Research discusses details of the forecast with ORACLES principal investigator Jens Redemann during the weather briefing. Credit: NASA/Jane Peterson

“We know that models aren’t perfect,” said Karla Longo of the Global Modeling and Assimilation Office at NASA’s Goddard Space Flight Center. The Goddard Earth Observing System or GEOS-5 model, for instance, tends to underestimate low-level clouds in this region.

“We have to use it here though so we understand when and why it’s wrong. People don’t always feel good about it, but it’s the only way to improve,” said Longo.

Part of the forecast briefing is devoted to looking back to the previous flight and comparing the forecast for it with what the plane actually found. Over the coming months and years, the ORACLES measurements will be used to update the physics that drive the model.

Meanwhile the science team is riveted because flawed or not, these are the images they need to plan the next flight.

CloudForecast
The cloud forecast made using the UK Met Office’s forecast model on Aug. 31 for the Sept. 2 flight day. It shows clouds at different altitudes in different colors: blue highest, green mid-level, and red lowest. Credit: UK Met Office

On an airborne mission like this there’s not a preset plan of where and when they will fly. Planning is done day by day. It’s a balance between the need for aircraft crew rest and the potential for good clouds and aerosol plumes to measure.

“We’re always concerned about low-level clouds and the amount of smoke in the biomass burning plumes,” said Redemann. “The juggling act is that our science objectives are diverse enough that we look for different plume and cloud characteristics on different days.”

After the forecast briefing to plan the flight for Friday, Sept. 2, Redemann gathers around a whiteboard with a few of the instrument scientists to hash out the nitty-gritty details of the main science section of the flight. The focus of Friday’s flight is radiative balance. They will design the flight plan to maximize the measurements taken by the Solar Spectral Flux Radiometer, which gauges the brightness of the clouds to determine the energy – light – in the atmosphere coming from all directions – directly from the sun, filtered through clouds, and reflected by clouds.

Sebastian Schmidt (center) and his team check the sensor of the Solar Spectral Flux Radiometer that sticks out of the top of the NASA P-3 aircraft. Credit: NASA/Jane Peterson
Sebastian Schmidt (center) and his team check the sensor of the Solar Spectral Flux Radiometer that sticks out of the top of the NASA P-3 aircraft. Credit: NASA/Jane Peterson

“The aerosol plume has a different effect on the radiation balance depending on whether the plume is above smooth or broken clouds,” said Redemann. Aerosols can have either a cooling or a warming effect, depending on the brightness of the clouds below. “We’re trying to verify that experimentally in flight.”

The science planning conversation is long and involves a shorthand language, squiggles on the whiteboard and questions like “Do you want to spiral here?”

Once they figure out the science plan, the pilots come in and work with the team to write their flight plans,  including when and where to fly the aircraft from the cloud tops down to a few hundred feet above the ocean surface in a corkscrew-like spiral.

By the end of the day it all comes together, and all that’s left is for the science teams to decide who gets to fly onboard with their instruments.

Mission Operations is set up in a conference room at the Swakomund Hotel in Swakomund, about a 45-minute drive from the Walvis Bay Airport and the NASA research planes. The weather forecast briefing is the highlight of every day. Credit: NASA/Jane Peterson
Mission Operations is set up in a conference room at the Swakomund Hotel in Swakomund, about a 45-minute drive from the Walvis Bay Airport and the NASA research planes. The weather forecast briefing is the highlight of every day. Credit: NASA/Jane Peterson

 

 

First Flight: “One of the Best of My Career”

by Ellen Gray / WALVIS BAY, NAMIBIA /

It’s chilly at 6 a.m. at the Walvis Bay Airport on Wednesday, Aug. 31. Only a couple of employees are here, two hours before the usual work day starts, to scan through security the science team for NASA’s ORACLES mission who are getting ready for the first complete science flight.

The airport is less than a year old with commuter flights from across southern Africa. It’s a tiny, two-story terminal, taking barely a minute to walk from one end to the other. It’s waiting area is still shiny and new, with red seats that will be filled by tourists coming and going in a few hours. But for now it is quiet.

A cloud of fine sand billows up as the P-3 moved down the runway at the Walvis Bay Airport. Credit: NASA/Jane Peterson
A cloud of fine sand billows up as the P-3 moved down the runway at the Walvis Bay Airport. Credit: NASA/Jane Peterson

On the runway in front of the hangar, the crew of NASA’s P-3 turbo prop aircraft readies it for flight. Today’s flight plan is called “Routine 1b.” “Routine” because the track — northwest from the airport over the Atlantic then turning due west — will be the regular route the team will fly over the next month to measure the low-lying clouds off the coast and the layer of aerosols above, primarily smoke from seasonal agricultural fires in central Africa.

The “1b” is for first flight, second attempt. Tuesday’s attempt at “Routine 1” ran into a minor technical issue with the aircraft half an hour into the flight that caused it to return early to base.

“There’s a real sense of excitement now that we’re here,” said David Noone of Oregon State University, one of the 24 scientists who was aboard the P-3 with an instrument to measure isotopes of water vapor. The water vapor that travels with the aerosols has a different fingerprint than the water in the clouds, and the measurements tell him how the two are mixing.

DSC_0052_DavidNoone
David Noone of Oregon State puts together the monitor for his instrument in the hangar at Walvis Bay Airport. Credit: NASA/ Jane Peterson

“We’ve been planning this experiment for three years,” said Noone. “So many people, so many logistics, so many challenges. To be here to start answering these critical science questions that affect future climate is really awesome.”

Aerosols and how they affect clouds are two of the biggest unknowns in climate science. The only way to learn how they work and affect Earth’s energy balance – how much heat sticks on the planet – is to fly through them both.

The P-3 is loud (best wear your ear protection!) when it fires up. Its propellers kick up a cloud of Namibian desert dust as it moves along the runway. At 8:00 a.m., it’s wheels up and they’re off.

Back in Mission Ops, a conference room at the Swakopmund Hotel a good 45-minute drive from the airport, the non-flying ORACLES scientists monitor the flight for the next eight hours. A web page projected on the big screen shows the plane’s location. A chat program allows the Earth-bound team to communicate via satellite with Rob Wood, the ORACLES flight scientist in charge on the P-3.

P-3 flying above stratocumulus clouds and under wispy cirrus clouds above. Credit: NASA/David Noone
P-3 flying above stratocumulus clouds and under wispy cirrus clouds above. Credit: NASA/David Noone

“This was my first flight on the P-3,” said Wood, ORACLES deputy principal investigator from the University of Washington, Seattle. “I was a little nervous about what I needed to do as flight scientist. It’s a totally new system to me. But the crew worked wonders to make it easy and get me fit into their system.”

After a long seven-and-a-half-hour flight, the whole science team is happy.

“It’s always good to get that first flight under your belt,” said Wood with a big smile on his face. “It’s even better when it’s such an amazing flight. This was up there with the best of my career.”

After Wednesday’s successful science flight, the science team debriefs in the hangar at Walvis Bay Airport. Credit: NASA/David Noone
After Wednesday’s successful science flight, the science team debriefs in the hangar at Walvis Bay Airport. Credit: NASA/David Noone

 

 

 

 

In Namibia: Between Dune and Sky

by Ellen Gray / WALVIS BAY, NAMIBIA /

This desert was nothing like what I expected. Flying in to Walvis Bay Airport in Namibia, Africa, unbroken beige stretched as far as I could see out the window, lined with the occasional road and dotted by the occasional black rock outcrop, like islands in the sea.

From the ground at first glance, it’s pretty boring in most directions: big sky and flat sand with little to interrupt the horizon. Until you turn and see what look like orange-ish mountains in the distance. They’re not mountains. They’re dunes. As we drive closer, they keep getting bigger. The Crocodile Dundee voice in my head says “Now, that’s a dune.”

Dunes of the Namib Desert near Walvis Bay, Namibia. Credit: NASA/Jane Peterson
Dunes of the Namib Desert near Walvis Bay, Namibia. Credit: NASA/Jane Peterson

The dunes are the most spectacular feature of the Namib Desert, one of the oldest deserts in the world, that runs the length of the Namibian coast on the western shore of Africa. But it’s the coast – specifically the clouds above the Atlantic Ocean to the west – that have brought a team of NASA and university scientists and two research aircraft to this remote region for a NASA airborne mission: Observation of Aerosols above Clouds and their Interactions (ORACLES).

Offshore are two things that make the coast of Namibia unique in the entire world: a layer of low-lying cumulus clouds and above that a steady layer of smoke particles – a type of aerosol – that are borne westward on the winds from forest and brush fires over central Africa.

NASA's P-3 aircraft is decked out with scientific instruments to study clouds and aerosols. Credit: NASA/Jane Peterson
NASA’s P-3 aircraft is decked out with scientific instruments to study clouds and aerosols. Credit: NASA/Jane Peterson

Aerosols and how they change the behavior of clouds are one of the biggest mysteries in the climate change puzzle. Do aerosols make clouds thicker? Do they reflect more sunlight, or change how much sunlight clouds reflect? Do they absorb sunlight and make the atmosphere warmer? The lessons learned from flying above and through this “perfect natural laboratory,” as principal investigator Jens Redemann put it, will yield insights into cloud-aerosol interactions around the world.

The same conditions that make the low-lying clouds also make the coast really foggy in the morning. The fog is a reliable source of moisture for the plants that cover rocks and boulders sticking out of the sand. Desert-warmed air condenses over cold ocean water to form a marine layer, similar to the ones seen on the California coast.

Swakopmund shrouded in morning fog at 6 a.m. Credit: NASA/Ellen Gray
Swakopmund shrouded in morning fog at 6 a.m. Credit: NASA/Ellen Gray

We are staying in Swakopmund, a tourist town about 45 minutes from the more industrial city of Walvis Bay. This is a former German colony town founded in 1892, and you can see the influence on the architecture. The town is built out rather than up. A constant breeze blows keeping the late August air a nice 70 to 75 degrees Fahrenheit.

As we drive south toward the airport on our first full day here, we’re between two extremes with the Atlantic ocean out the right window and the desert out the left.

DSC_0024
Man walking near the highway on the desert side near Walvis Bay. Credit: NASA/Jane Peterson

The ocean is blue and huge, and vacation rentals dominate a long section of beach, giving way to a view of offshore drilling platforms in the distance as we near the city of Walvis Bay. Like Swakopmund, the city is spread out, and signs on the highway caution to watch out for children crossing between two residential areas.

Sign for Walvis Bay Airport which is off in the distance toward that hill in the top left. Credit: NASA/Jane Peterson
Sign for Walvis Bay Airport which is off in the distance toward that hill in the top left. Credit: NASA/Jane Peterson

At the southern reach of the city new construction is going up as we turn inland toward the desert and the airport.  The dunes in the distance grow until we pass Dune 7, the tallest in the area at over 1200 feet. Out here, under the sun, the temperature will be in the 90s F by midday.

Soon after we arrive at Walvis Bay Airport, a tiny bump on the horizon that will be the ORACLES base of operations for the next month. A spill of scientists, freshly badged for airport access, disembark out of the shuttle van, ready to go.

Dune 7 from a distance. Credit: NASA/Jane Peterson
Dune 7 from a distance. Credit: NASA/Jane Peterson

 

 

Our Big Finish: Africa, Australia, Greenland

by Steve Cole / WASHINGTON, DC /

For the next month Earth Expeditions lives up to its name as we wrap up our reporting on NASA scientists in the field by taking you to three far-flung locations around the world. Our final trio of 2016 expeditions is exploring the edges of the Greenland ice sheet, potential climate changes in clouds off the Atlantic coast of Africa, and the condition of the Great Barrier Reef in Australia.

NASA photographer Jane Peterson on the tarmac in Walvis Bay, Namibia.
NASA photographer Jane Peterson on the tarmac in Walvis Bay, Namibia.

Our reporting team has just arrived in Walvis Bay, Namibia, for the start of the ORACLES airborne campaign looking into the complex interactions of tiny aerosol particles and clouds and their impact on climate. Two NASA aircraft are now at Walvis Bay for the mission, which will continue through the end of September. Our team begins blogging right here tomorrow!

Where there’s smoke there’s fire, but what if there are also cloud condensation nuclei? Clouds help to keep the planet cool by reflecting sunlight back into space. Aerosols such as smoke particles contribute by mixing with water vapor, resulting in “cloud seeds” that, in addition to forming raindrops, create brighter and more reflective clouds. On the flipside, smoke particles can absorb sunlight and contribute to atmospheric warming.

ORACLES mapThe ORACLES (Observations of Aerosols above Clouds and Their Interactions) campaign takes to the skies of the southern Atlantic to investigate this cloud-aerosol phenomena. “Aerosols work as a sort of a sun-umbrella,” said ORACLES principal investigator Jens Redemann. “Whether they’re absorbing or not, they have implications for clouds and cloud formations.”

In mid-September another NASA reporting team will be traveling with the Coral Reef Airborne Laboratory (CORAL) mission to the land down under to probe portions of the Great Barrier Reef.  CORAL is looking at the interplay of factors that influence these complex underwater ecosystems.

CORAL map

To date coral reefs have primarily been studied with scuba gear and a tape measure as the dominant tools of the trade. But CORAL will investigate reefs en masse with the use of an airborne instrument to record the spectra of light reflected upward from the ocean. Those measurements allow researchers to pick out the unique spectral signatures of living corals, sand and algae as well as create ecosystem-scale models of reef conditions.

The Earth Expeditions team will be reporting from Cairns, North Queensland – the gateway to the Great Barrier Reef – and Heron and Lizard Islands. CORAL will sample six sections across the length of the reef, from the Capricorn-Bunker Group in the south to the Torres Strait in the north.

“CORAL is a unique opportunity to obtain a large uniform data set across several reef systems. This will give us a whole new perspective on coral reefs,” said Eric Hochberg, CORAL principal investigator. Future field work of the three-year field campaign will inspect coral reefs in Hawaii and the Micronesian islands of Palau and the Mariana Islands.

OMG map

On the opposite side of the globe from Australia, the Oceans Melting Greenland (OMG) campaign will be dropping some 250 probes from a NASA aircraft into the waters on Greenland’s continental shelf and in its fjords. The probes measure ocean temperature and salinity as they sink thousands of feet into the water, transmitting the data to the aircraft above. Combined with OMG’s new maps of the seafloor along the coast, the probe data will show where warm, subsurface waters can come in contact with the undersides of glaciers and melt them from below.

The rate of underwater melting in Greenland has been one of the greatest uncertainties in predicting future sea level rise, according to Josh Willis, OMG’s principal investigator. With the intensive measurements that OMG will gather in its five-year span, “We may not solve the problem of predicting sea level rise, but we hope to make a dent,” he said.

To reach all of Greenland’s coastline — which is eight times the length of the U.S. East and West coasts combined — the OMG team will use four different bases in Greenland, Iceland and Norway between mid-September and early October. Our Earth Expeditions reporting team will document OMG’s work as winter approaches in the Far North.