BOREAS Intensive Field Campaign #1 (IFC-1) officially ran from April 2 through 28, 1996. In practice, a number of teams were bravely floundering around in the alternating snow/slush/mud admixture and unseasonably low temperatures (-20 degree C and below) from the end of the winter field campaign onwards, i.e. February 27, 1996. In a very real sense then, BOREAS field operations started in mid-February (after getting the green light on January 11, 1996) and have not stopped since.
The goals of IFC-1 were straight forward; be onsite to measure surface-atmosphere fluxes of energy, water and carbon (CO2 and CH4) as the boreal forest emerges from winter dormancy. This involves the operation of flux measurement equipment from the tops of tall towers that extend above the forest; measurements with small chambers clamped over tree branches and onto the soil/moss surface; and dozens of supporting state variable measurements. No remote sensing aircraft were deployed in IFC-1 (we made a clean sweep of data acquisitions in May of 1994, so decided that it was not necessary to repeat this work) and only one aircraft equipped with CO2 concentration measurement equipment was fielded to carry out a series of transect and profile CO2 measurements.
The weather conditions were unusual. It could be said that the BOREAS team
was on time for the thaw, but not the other way around. It was very cold
at the beginning of the IFC, which helped in terms of moving equipment and
fuel drums for the power generators over the frozen trails into the sites,
and only really warmed up in the last 10 days of April. CO2 concentration
and flux measurements showed very little activity until this last period
when at last the CO2 concentration started to rise from a boringly constant
value of 369 ppm to 370 and then 371 ppm, as the thawing soil began to
release CO2 into the air. By this time, the tower flux teams and other
scientists were ready and rested, if not tanned, and went to work. So far
no big problems have been reported with getting the data specified in the
BOREAS Experiment Plan for 1996 (EXPLAN-96).
BOREAS Operations were staffed by teams from NASA/GSFC during
the IFC (Fred Huemmrich, Shelaine Curd, and Tracy Twine in the SSA; Beth McCowan and Dave Landis in the NSA). Dan Hodkinson and Ross Nelson were onsite to organize logistics and run the perennial tower-climbing courses. Scott Mifflin, who is the new NSA Site Manager, is a thoroughly enthusiastic and competent addition to the team; Paula Pacholek in the SSA is continuing to provide her excellent talents to the project. Piers Sellers and Forrest Hall both visited the site in IFC-1.
Fred Huemmrich worked on comparing the European Center for Medium Range
Weather Forecasting (ECMWF) 12- and 24-hour forecasts with observations to
prevent himself from going crazy in the snow-bound isolation of BOREAS
Operations-SSA. Whenever the ECMWF model predicted snow on the ground, the
near-surface air temperatures were underestimated by up to 20 degree C! Whenever
the surface was predicted to be snow-free, the observed and predicted
temperatures converged to within 1 degree C or so. Obviously, the very large
errors in the snow case forecasts make the forecasts useless for local
aviation planning or any other purpose. A dialogue with scientists at
ECMWF has revealed that they currently specify the snowbound forest to have
an albedo (reflectivity) of about 80%, the same as on open snow-covered
field, whereas in practice the forest canopies stick up above the snow and
give rise to a relatively low albedo, 12% or so, which is only a little bit
more than when it is snow-free. ECMWF is working on a fix.