ATom 2016: World Survey of the Atmosphere: Instrument Prep and ATom’s First Test Flight

July 22nd, 2016 by Christina Williamson

I’m Christina Williamson, a postdoctoral scientist at CIRES CU-Boulder/NOAA-ESRL interested in Atmospheric Aerosols, the small particles in the air that cause haze, and on which clouds are formed.

I’m working with a few colleagues from NOAA to take a suite of instruments on NASA’s ATom mission that will measure the number and size of particles in the air as we fly around the world. We’re interested in this because aerosols in the atmosphere affect how much of the energy from the sun is absorbed and how much is reflected back to space by clouds and by the aerosols themselves.

My research team in our lab at NOAA ESRL setting up our flight rack for ATom. From left to right, Frank Erdesz, engineer with CIRES/NOAA, Charles Brock, Principal Investigator from NOAA, Agneiszka Kupc, research scientist with NOAA/University of Vienna, and Christina Williamson, research scientist with CIRES/NOAA. (Credit: Nick Wagner)

My research team in our lab at NOAA ESRL setting up our flight rack for ATom. From left to right, Frank Erdesz, engineer with CIRES/NOAA, Charles Brock, Principal Investigator from NOAA, Agneiszka Kupc, research scientist with NOAA/University of Vienna, and Christina Williamson, research scientist with CIRES/NOAA. (Credit: Nick Wagner)

Over the past few weeks we’ve brought our instruments down from NOAA’s Earth-Science Research Laboratory in Boulder, Colorado to NASA Armstrong in California, integrated them onto the plane and tested how they perform while the plane is flying. We’re running five instruments, measuring aerosols in different size ranges, which, after modifying to optimize performance for ATom conditions, and testing in the lab, we put together in a flight rack. Everything we fly is secured in the rack with aircraft grade hardware so that it cannot shake loose or be propelled out during flight, and the rack is then screwed to the seat tracks of the plane.

Assembling the instrument rack in the lab at NASA Armstrong. From left to right, Frank Erdesz, engineer with CIRES/NOAA, Charles Brock, Principal Investigator from NOAA, Agneiszka Kupc, research scientist with NOAA/University of Vienna, and Christina Williamson, research scientist with CIRES/NOAA. (Credit: Maximilian Dollner)

Assembling the instrument rack in the lab at NASA Armstrong. From left to right, Charles Brock, Principal Investigator from NOAA, Agneiszka Kupc, research scientist with NOAA/University of Vienna, and Christina Williamson, research scientist with CIRES/NOAA. (Credit: Maximilian Dollner)

We sample aerosols in flight by pulling air in through an inlet tube that is mounted on a plate where the window would normally be. We plumbed this to our instruments taking care to route the flow to minimize the number of aerosol particles that get lost by sticking to the walls of the tubing on their way from outside to the instruments.

Instrument inlets (where air is pulled into the instruments inside for sampling) on the NASA DC-8. Ours is the curvy one third from the right. (Credit: NASA Armstrong)

Instrument inlets (where air is pulled into the instruments inside for sampling) on the NASA DC-8. Ours is the curvy one third from the right. (Credit: NASA Armstrong)

On the plane we tested the instrument set-up while it was still in the hangar, checking for leaks and that particles were being transmitted well, as well as other things like electrical connections and communications. I ran some calibrations to check that nothing had shifted in the instrument performance in the move from the lab. We also spend a good deal of time neatly tying down all of the cabling and plumbing, securing it to the rack and the body of the plane and making sure everything in the rack will hold fast during even the most turbulent of flights.

The AMP (aerosol microphysical processes) rack installed on the DC8. We run all 5 instruments from this monitor, and check the data as it comes in during the flights. (Credit: Christina Williamson)

The AMP (aerosol microphysical processes) rack installed on the DC8. We run all five instruments from this monitor, and check the data as it comes in during the flights. (Credit: Christina Williamson)

The AMP (aerosol microphysical processes) rack being integrated on the DC8. You can see there’s some work to be done neatening and tying down the cabling. The instruments on the top are two Nucleation Mode Aerosol Size Spectrometers (NMASSs), which measure aerosol size distributions between 3 and 60nm. Lower in the rack are two Ultra High Sensitivity Aerosol Spectrometers (UHSASs), which measure particles between 60 and 800nm, and a Laser Aerosol Spectrometer, getting the size distribution from 90nm up to 7.5μm. (Credit: Christina Williamson)

The AMP (aerosol microphysical processes) rack being integrated on the DC8. You can see there’s some work to be done neatening and tying down the cabling. The instruments on the top are two Nucleation Mode Aerosol Size Spectrometers (NMASSs), which measure aerosol size distributions between 3 and 60nm. Lower in the rack are two Ultra High Sensitivity Aerosol Spectrometers (UHSASs), which measure particles between 60 and 800nm, and a Laser Aerosol Spectrometer, getting the size distribution from 90nm up to 7.5μm. (Credit: Christina Williamson)

All this involved many days working on the plane in the hangar. Palmdale, where the Armstrong base is located, can get above 40C (104F) this time of year. The air-conditioning from the plane’s ground unit cannot quite compete with combination of heat from outside and from electrical scientific equipment operating inside (not to mention a lot of busy scientists and crew), so it gets pretty hot. We’re working often in the cramped spaces between two instruments, or a rack and the wall, or laying cabling and plumbing along the floor, so it’s hot, awkward and dirty work, but the excitement of working on the plane and seeing everything come together for the flights more than compensates for that.

The crew conducted a shakedown flight without scientists just to check that everything was integrated safely, and then we went up for out first test flight on July 12. This was my first time flying in a research plane. Some more experienced scientists delighted in telling me horror-stories of maneuvers and low-flying turbulence making people ill before we took off. I was nervous, mainly about how my instruments would perform, as there are controls for things like pressure and flow that I can’t test on the ground, and also because I didn’t want to embarrass myself by getting ill on the test flight.

Christina Williamson (i.e. me), research scientist with CIRES/NOAA boarding the DC-8 for our first test flight at NASA Armstrong. (Credit: Agnieszka Kupc)

Christina Williamson (i.e. me), research scientist with CIRES/NOAA boarding the DC-8 for our first test flight at NASA Armstrong. (Credit: Agnieszka Kupc)

We flew from the base out over the Pacific, then back inland over the LA-Basin and back to base. The ATom mission flights will be constantly profiling between about 0.2 and 12km (650 feet to 7 miles) altitude, so we did a lot of ascending and descending to check that the instruments can cope with it and to look at the fuel performance of the plane with this payload. To really test every instrument, the pilots did some really fast ascents and descents (for example, flow into the inlets is affected by the incline). I had to be up out of my seat testing some things on the instrument during part of this: the crew really weren’t joking when they said to hang on.

Our instruments behaved well, needing just one or two quick software fixes that I was able to implement as we flew, and I started to relax and enjoy the flight. We can stream video from cameras in the cockpit and one looking directly down below the plane, which is great. We also have a window by my seat, so I can look out.

Once over the Pacific and out of the LA-area high air traffic we dropped seriously low — had there been a whale breaching below I would have easily seen it. We also did some very low flying over the Central Valley, which produced interesting data and interesting views (although also a reasonable amount of turbulence).

Photo from the DC-8 flying low over the Pacific Ocean on the first ATom test flight. (Credit: Christina Williamson)

Photo from the DC-8 flying low over the Pacific Ocean on the first ATom test flight. (Credit: Christina Williamson)

During the flight we had to do some maneuvers. These are used to calibrate instruments measuring wind-speed. The crew advised us to sit down for these, and I’m glad I did, as some of them had my body weight almost out of the seat and pulling on the seatbelt. If you throw a small object in the air during one of the maneuvers you can watch it appear to hover as it falls under gravity but then you and the plane also move down away from it. It felt a bit like being in a roller coaster, and by the end of all the maneuvers I was glad to return to more normal flight. It can make you a little queasy, but just eating something or walking about the cabin afterwards really helps.

Agneiszka Kupc, research scientist with NOAA/University of Vienna, monitoring data during the first ATom test flight. (Credit: Christina Williamson)

Agneiszka Kupc, research scientist with NOAA/University of Vienna, monitoring data during the first ATom test flight. (Credit: Christina Williamson)

The aircraft is noisy in flight, partly because there is less insulation on it than on a normal passenger plane, and partly because of all the pumps and fans etc. on our instruments. We therefore all wear headsets, which cancel background noise and enable us to communicate with other scientists and the crew. We get some bleed-over from the channel the pilots are on, which is quite fun.

Christina Williamson (yup, me again), research scientist with CIRES/NOAA on the DC-8 during the first ATom test flight. (Credit: Christina Williamson)

Christina Williamson (yup, me again), research scientist with CIRES/NOAA on the DC-8 during the first ATom test flight. (Credit: Christina Williamson)

I was quite surprised when we arrived back already, four hours of flight goes by so quickly when you’re operating instruments and concentrating on the science behind what you’re seeing compared to a passenger flight. It was a good feeling to have a successful flight under the belt, to see that the instruments worked as expected and that my body coped fine with the flying conditions. We have one more test-flight just before we take off for the mission-proper. I’m looking forward to it!

Christina Williamson blogs regularly about the ATom Mission and other adventures in atmospheric science at christinajwilliamson.wordpress.com and tweets as @chasingcloudsCW.

ATom 2016: World Survey of the Atmosphere: ATom Mission to Sample the Atmosphere is Ready for Take Off

July 21st, 2016 by Ellen Gray

Take 78 percent nitrogen, 21 percent oxygen, 0.9 percent argon, 0.03 percent carbon dioxide – that’s 99.93 percent of the atmosphere. But the trace gases and airborne particles that make up that last approximately 0.07 percent are what NASA’s Atmospheric Tomography (ATom) mission is interested in.

ATom is a chemistry mission to study the movement and chemical processes that affect the top three greenhouse agents after carbon dioxide – methane, tropospheric ozone, and black carbon. In addition, it’s the first time scientists are going to do a comprehensive survey of over 200 gases and aerosol particles all over the world. And to do that a team of university and NASA scientists are going on a 26-day journey from pole to pole and back again.

NASA's DC-8 aircraft has intake valves on the window ports to suck in the air it's flying through. Credit: Michael Prather (UCI)

NASA’s DC-8 aircraft has intake valves on the window ports to suck in the air it’s flying through. Photo taken July 11 in Palmdale, California, before ATom’s first test flight. Credit: Michael Prather (UCI)

Over the next few weeks a handful of ATom scientists will be blogging about their around-the-world journey on NASA’s DC-8 flying laboratory – a plane the size of a midsize commercial airliner stuffed with 22 scientific instruments for sampling the air. They’ll collect data that not only shows where these hundreds of trace gases are hanging out and where they’re going, but also how they interact with each other – creating new compounds or destroying others, like methane, and effectively removing them from the atmosphere. Taken together, the data will give the science community a better understanding of how these gases, many of which are pollutants, affect global climate change.

The majority of the air sampled will be over the Pacific and Atlantic oceans. This summer’s trip will be the first of four deployments, one in each season over the next three years.

To learn more about ATom’s science goals and its ten-leg flight path, stay tuned.

Greenland Aquifer Expedition: Ready for the Field

July 20th, 2016 by Stefan Ligtenberg

We are ready for the big day! Tomorrow (Wednesday) we will start our put-in to the field. With a total of 5 helicopter flights all our gear, science equipment and the entire team will be flown to our field site, approx. 130 km northwest of Kulusuk. However, we have to take the weather in account; if it is foggy on the ice sheet the helicopter will not be able to land and the put-in will be postponed. So, fingers crossed!

View from the village of Kulusuk. Great weather!

View from the village of Kulusuk. Great weather!

During the past three days, the team arrived according to plan: Rick and Kip on Sunday morning and, last but not least, Nick on Monday morning. Having the entire team in Kulusuk made the organization of the equipment rather quick and smooth. To give you an idea of the preparations we have done: we checked and strengthened about 100 bamboo stakes, repaired tears in the tents, tested the generators, checked the gasoline on contamination with water, charged ~20 batteries, and every group sorted and tested their own science equipment. In the end, we had 132 packed and weighted items ready to be taken to the field.

This afternoon the BlueWest helicopter arrived from Reykjavik with our two pilots Johannes and Nicola. They crossed the ocean from Iceland to Greenland on the narrowest part as that is about the maximum distance the helo can fly. From there they followed the Greenland coast southward till Kulusuk. On the way, they saw seals and a group of 10 whales from the helicopter. That must have been an awesome sight!

Kip replacing the coupling on the borehole liners.

Kip replacing the coupling on the borehole liners.

Packing the first sling load with the BlueWest helicopter on the right.”

Packing the first sling load with the BlueWest helicopter on the right.

Today, we also had time to test and practice our drone-flying skills! This year, we brought a drone with us for both a serious and less serious goal. First the serious one, we will use it to scan the lowest section of our study area for crevasses. These cracks in the ice are very dangerous as they can be very deep, so it is not advisable to go close to them! However, as the ice sheet is very flat you sometimes cannot see them until you are dangerously close. With the drone we hope to spot them earlier and keep a safe distance. Next to this, the drone will be able to make a number of priceless pictures and videos of us doing science.

Photo from the drone: Nick, Stefan, and Rick in front of Hotel Kulusuk.

Photo from the drone: Nick, Stefan, and Rick in front of Hotel Kulusuk.

Now it is time to finish packing, take a last shower and go to sleep. Tomorrow, there are three flights scheduled: first our camping equipment will be flown in by sling, followed by a part of the team who will set up camp. The science equipment will be flown in next. The next day, the snow mobile and fuel are brought in followed by the last passenger flight. At least that is the plan, the weather can still change everything…!

Greetings from Kulusuk! Olivia, Nick, Clem, Rick, Kip, and Stefan.

Greenland Aquifer Expedition: Welcome Back! Greenland Aquifer Expedition Resumes

July 15th, 2016 by Olivia Miller, University of Utah
The view from Hotel Kulusuk, looking at snow-free mountains

The view from Hotel Kulusuk, looking at tefnow-free mountains.

Welcome back to our blog! We’re here for one more season of field work on the Greenland ice sheet to study the firn aquifer. Surface meltwater percolates through the upper layers of compacting snow, or firn, and pools inside the air space between sow grains, forming a large reservoir of liquid water within the ice sheet. We’re trying to figure out how much water is in the aquifer, how fast the water flows, and if and where it is leaving the ice sheet to potentially flow into the ocean. We need to learn more about the firn aquifer because it is a huge reservoir of meltwater in the ice that was only discovered in 2011, and it could have big impacts on how the ice sheet melts and causes sea level rise. This is one of the most exciting parts of science – new discoveries are always being made!

2016team-(1)_forweb

Our team this year consists of Rick Forster, Kip Solomon, Clement Miege, and Olivia Miller from the University of Utah, Nick Schmerr from the University of Maryland, and, our newest member, Stefan Ligtenberg from the University of Utrecht.

We plan to do some similar experiments as last year (see our past blog posts) but in new locations to see how the aquifer changes in different places, and we also have a few new experiments up our sleeves to try to fill in some knowledge gaps that we discovered following the two field campaigns last year. That is another fun thing about science – through your work, you discover new information you need, and then you get to design new ways to get that information.

View of Kulusuk from the air.

View of Kulusuk from the air.

We will spend a few days in Kulusuk getting our equipment ready for the helicopter flights out to the ice sheet. When we get to the ice sheet, we will set up camp, and then get to work. We plan to spend 3 weeks on the ice.

Our science plan for this year includes:

  • Drilling ice cores to measure snow, firn and ice densities
  • Installing wells into the aquifer to take water samples and to measure how easily water flows through the firn
  • Ground penetrating radar to image the height changes of the water table inside the firn spatially
  • Seismic surveys to detect the bottom of the aquifer and measure how much water is in the firn
  • Magnetic resonance soundings to measure how much water is in the firn
  • Dye experiments to measure how quickly surface melt reaches the aquifer
  • Saltwater injection experiments to measure how quickly water flows through the firn
  • Self potential experiments to measure water flow

This year we have a new, exciting partnership with a research project called STEM Ambassadors. The STEM Ambassadors team is trying to learn about ways to improve science outreach, and so I have volunteered to try some new outreach activities out for them. I wrote a short children’s book about our field work for the school in Kulusuk, and had it translated into West Greenlandic and Danish. This was a very new type of writing for me, but I had a lot of fun! I’ll pass the book along to the teachers in Kulusuk so they can share it with their students when school begins in the fall. If you want to see the book, you can find it here. Any feedback is welcome!

We’ll update the blog regularly over the next few weeks, and look forward to learning more about this unique feature of the Greenland ice sheet! Also, please feel free to leave us a note at the bottom of the page.

The Ablation Zone: Where Ice Goes to Die: Successful Camp Put In!

July 8th, 2016 by Clément Miège

Hi there,

After an early breakfast, our team is getting ready to put in our ice camp. We met with the pilots around 8:30am for a departure at 9 am. The flight to the ice camp was quick, about 20 minutes. Beautiful views of the fjords leaving Kangerlussuaq and then on our climb onto the ice sheet we saw the first supraglacial rivers flowing over the ice sheet. After arriving at our camp location, a team of two got back in the helicopter to be ferried to the other side of the river. The plan was to anchor a Tyrolian line across the river to suspend an Acoustic Doppler Current Profiler (ADPC) on the river and collect data. In the meantime, the team members set up tents, and outhouse, a kitchen tent and organized the camp. In the afternoon, the team of two was picked up from the other side of the river and brought to camp.

We got to spend our first night on the ice sheet, nice, quiet and not too cold!

See below a few photos taken that first day.

First views of the rivers sitting on the ice sheets. Photo by Brandon.

First views of the rivers sitting on the ice sheets. Photo by Brandon Overstreet.

 

Unloading the helicopter shortly after arriving at ice camp location. Flemming, our helicopter pilot says hello! Photo by Lincoln.

Unloading the helicopter shortly after arriving at ice camp location. Flemming, our helicopter pilot says hello! Photo by Lincoln Pitcher.

 

Brandon posing in front of the gear and the helicopter at the background. Photo by Lincoln.

Brandon posing in front of the gear and the helicopter at the background. Photo by Lincoln Pitcher.

 

Rigging up the tyrolean system to move gear across the river. Photo by Brandon.

Rigging up the tyrolean system to move gear across the river. Photo by Brandon Overstreet.

 

Caption: View of ice camp and helicopter. Photo by Lincoln Pitcher.

Caption: View of ice camp and helicopter. Photo by Lincoln.

We will send new updates once we are back from the ice camp around July 14.

Best wishes from our ice camp!

Clém

Notes from the Field