Let the Field Research Campaign Begin!

The NGEE Arctic project (http://ngee-arctic.ornl.gov/) has enjoyed five successful field seasons working at our research site near Barrow, Alaska. This year – thanks to the hard work of many people – we begin a new chapter in our efforts to integrate field and laboratory studies in support of advancing climate model development for the Arctic. Our team is expanding to include field sites outside Nome on the Seward Peninsula in western Alaska.

While this is certainly not our first trip to Nome, it will be our largest. Several dozen of our scientists, students, and staff will travel to the area throughout the next few weeks. Our team will conduct a broad range of integrated research activities at an intensive field site along the Teller Road. We are thankful to the Sitnasuak Native Corporation for making this land available for our use. Other native corporations are being engaged to also identify field sites along the Kougarok and Council roads.

 

The NGEE Arctic team will, working first at the Teller site, use an array of geophysical approaches to establish interactions between permafrost and bedrock, and to examine the consequences of those interactions to watershed hydrology. Complementary studies of vegetation, biogeochemistry, and energy balance will help inform our understanding of Arctic tundra and provide insights for developing multi-scale numerical models for inclusion into climate models. Our goal is to better understand the fate of frozen soil organic matter (i.e., the permafrost carbon cycle) in a warming climate and incorporate critical feedbacks into models. We were fortunate to begin collecting initial datasets last year and will continue to expand on those with increasingly detailed field and modeling investigations of the Teller Road watershed.

 

The next three weeks will be a productive time for our team. Our planning has laid a foundation that we will continue to build upon, ensuring that our interdisciplinary science delivers on expectations and does so in a safe and efficient manner. We are thankful that while working thousands of miles away from our home institutions can be challenging, our team has the support and cooperation of people and facilities like Bob, Gretchen, Claudia, and others at the UAF Northwest Campus in Nome.

While the next few weeks will be busy ones, I’ll do my best to provide periodic updates on the science being conducted by our team and how those research results and acquired knowledge is incorporated into models, including global-scale Earth System Models.

Tundra Tram – Up and Running

Field research for the NGEE Arctic team is off to an early start. There have been, and currently are, team members conducting snow surveys at our field sites on the Seward Peninsula. And there have been plenty of preparations for field studies on the North Slope as well. This week, Bryan Curtis (LBNL) and I travelled to Barrow for a number of activities; foremost among them was the reinstallation of the tram on the Barrow Environmental Observatory (BEO). We had disassembled the tram last fall and moved all the infrastructure and cart to storage facilities. This was done for several reasons, one being to remove the physical infrastructure from the field so that it did not pose a safety risk to local people who might traverse the BEO using snow machines during the winter. Another was to continue to upgrade the suite of sensors on the cart which required it to be shipped back to LBNL.

Our first task in Barrow was to transport all the uprights and supporting rails from storage to the field site several kilometers away. This was done by loading the materials onto wooden sleds and then transporting everything to the field using snow machines. Although much of the tram is constructed of aluminum, it is still heavy and required multiple trips to and from the field before everything was in place. It was cold with high winds in the afternoon. However, the weather cooperated and we had plenty of daylight for moving materials to the field.

When Bryan and I were not transporting materials to the field, the sensor cart was assembled and all components were tested including sensors, data logger, and control programs. This required several days of effort but no surprises due to careful planning by Bryan and others at LBNL.

Once everything was in the field it was just a matter of getting everything installed. The system was designed for ease of installation and thanks to the carefully planning by a number of people, including systems engineer Keith Lewin at Brookhaven National Laboratory, the uprights and raised rails were up, leveled, and ready for testing with only two days of effort.

The cart was the last thing to be transported to the field, and it too was easy to install. Once all the sensors had been connected the system was ready for testing. Everything worked perfectly! The cart made its maiden 2016 trip down the rails on April 20, collecting data every 0.5 meter along the 65-meter length of the tram.

Bryan will be keeping an eye on the system as he, and Sigrid Dengel (LBNL) now turn their attention to getting the eddy covariance system up and running. John Peterson and Emmanuel Legger, both from LBNL, will also be joining Bryan and Sigrid for a few days in order to reinstall the geophysics (ERT) array and take a few permafrost cores for physical characterization.

It was a great trip – thanks!

Erector Set...

Bob Busey, Cathy Wilson and Lily Cohen finished up the catchment-wide snow surveys on Friday and Saturday under mostly sunny skies and began preparation for our final task of the trip. The challenge was to construct two mobile snowmelt stations at the NGEE Teller site using the fewest, lightest, shortest, easiest to assemble, pieces of observation equipment, tower infrastructure, hardware and tools. It all needed to fit in the 5ft x 2ft x 2ft belly pod and back seat of a helicopter, and take a day and half to construct and test. Thanks to Bob Busey’s creativity and careful preparation in Fairbanks, we landed at the field site on Saturday with our artfully compact load and got to work building the stations.

One of the novel aspects of the station design was the use of survey tripods as the foundation of the infrastructure. These are easy to carry and set up in any terrain.  Bob designed to stations to mount on top of the tripods with unistrut and interlocking, lightweight aluminum poles. The snow sensor, temperature and relative humidity sensor, net radiometer, game cameras and data logger boxes were then mounted off of this simple scaffold.

While Bob and Lily constructed the tower infrastructure, I dug a pit in a snowdrift banked against a shrub thicket to install Bob’s new snow temperature profiler. The profiler has thermistors spaced every 4 centimeters along a wooden rod that has approximately the same thermal conductivity as snow. When inserted upright into the face of a pit, it continuously measures the temperature of snow from the ground surface up through the snow pack to the top of the ~90cm tall unit. We will use the instrument to assess changes in thermal conductivity in the snow pack as a function of depth and time during snowmelt. After installing and burying the profiler, and running its cables through a trench to the snowmelt station pit, I assisted Lily as she built the “yellow” snowmelt station in the shrub drift, while Bob completed the “blue” runoff observation snowmelt station overlooking the creek.

 

On Sunday we put the finishing touches on both stations and deployed two pressure transducers in the creek that was already flowing due to the unusually warm early spring temperatures. In fact, areas of shallower snow pack including the “blue” snowmelt station site were shrinking fast, leaving large patches of bare ground that had been snow covered two days earlier.

By Sunday afternoon we were packed up and ready to leave the site. Cathy got one more look at the two completed stations as she ferried the first load of empty action packers and tools back to Nome. She also spotted one of the first grizzlies of the season just a few miles North of the airport. Sunday night was spent reorganizing gear for the snow survey in Barrow this week, and snowmelt survey back at Teller next week.

Fair Weather...

We couldn’t ask for two more perfect days.  With brilliant warm sunny days we collected nearly a thousand snow depth measurements at intensive sites and along transects that cross the Teller NGEE watershed. As we climbed out of the site in the helicopter at 8pm, we could see the faint tracks of the tens of thousands of footsteps along remarkably straight survey lines that form the Teller snow grid. 

Every ten meters along kilometers of transects we collected snow depth measurements in order to quantify the spatial patterns of snow distribution in relation to vegetation type, slope, aspect, topography and elevation. For each transect Bob and Cathy set up a directional bearing using hand held gps, Lily Cohen (UAF) paced off distance using a three-meter-long avalanche probe, Cathy measured snow depth with a thaw probe and Bob Busey collected high resolution position data with the Trimble differential GPS rover.  

Given the depth and density of the snow pack we adjusted our snow density measurement goal from 40 sites to 10, and noticed that within just two warm days the snowpack had gotten significantly more “rotten” and wet.  In the mornings water in the snow pack froze into icy layers that were difficult to penetrate with the snowpack density tube, but by the afternoon the snow was so soft we struggled to stay upright, expending significant effort extracting ourselves from thigh deep postholes, even though we wore snowshoes or skis. On Saturday we will install two temporary mini-meteorology stations to track changes in the snow pack and radiation balance in anticipation of snowmelt, which will start soon if temperatures continue to stay warm.