OASIS-CANADA experiments during Barrow-09

1. Characterization of the lower atmosphere

(Staebler/Steffen/Lee/Sheppard EC, Whiteway/Seabrook YU, Abbatt/Sjostedt UoT)

To characterize the lower atmosphere up to a height of about 800m, a Scintec MFAS sodar will be operated either from the roof of BARC or near the wannagans. Ozone profiles up to several km will be measured by the York University group (Jim Whiteway) with their DIAL system. Hydrocarbons will be measured by the University of Toronto group (Jon Abbatt) by PTR-MS.  Gaseous Elementary Mercury (GEM) will be measured by a Tekran 2537A monitor.  The PTRMS and Tekran 2537A plan to obtain profile information using the common sample line hoisted by the tethered balloon from U Colorado, and be housed inside one of the wannagans.  Mercury speciation involving measuring reactive gas phase mercury (RGM) and mercury associated to particles (PHg) will be accomplished with a complete Tekran speciation system (Tekran 2537A, 1130, 1135), see photos below.  This equipment will be placed outside near the wannagans from which power will be obtained.  Measurements will be from near surface air only since sampling via an extended sample line is known to introduce unacceptable wall losses.  Note that microwave profiler data of temperature and humidity are available at Barrow (ARM?), and access to these data will be sought, under some collaborative agreement.

2. Lower boundary layer flux

(Staebler/Netcheva/Bottenheim EC, Guenther/Turnipseed NCAR, Fuentes UVa)

A group consisting of Alex Guenther, Andrew Turnipseed (NCAR), Jose Fuentes (UVa) and Ralf Staebler (EC) is planning to do eddy covariance measurements of the fluxes of momentum, sensible and latent heat, and ozone above the snow surface. Measurements will take place about 25m from the wannagans near the BARC, perpendicular to the prevailing wind direction, from a 6m triangular tower. On this tower will be mounted 3 ultrasonic anemometers at heights of approximately 0.3m, 1.5m and 4m, a radiation-shielded temperature profile, and various filtered inlets for tubing connected to gas analyzers including a “fast ozone” monitor based on NO chemiluminescence. The objective is to quantify surface-atmosphere exchange under various arctic surface conditions, and to develop methods to deal with the predominant conditions of stable surface stratification.
In support of these measurements one full OOTI sled will be continually operating near the flux tower (measuring low level concentration gradients of ozone and mercury, BrO by MAXDOAS, and the usual OOTI-met parameters)

3. OOTI on Elson lagoon frozen sea ice

(Netcheva/Bottenheim/Staebler/Steffen/Lee/Sheppard EC)

The second OOTI sled will be operating on different ice surfaces at the Elson lagoon to determine concentration gradients .  The OOTI sled was successfully operated for this purpose during the COBRA campaign in February/March 2008 (see photo).  It is planned to have the sled out on the ice for several days at a time.  The OOTI sled and the mercury speciation system (see below) will also operate for selected periods near the test site for the O-buoy. 
The Elson lagoon has been selected as the best compromise location for measurements over a sea-ice surface, since the experience in 2005 has learned that operating an OOTI sled near the open lead on the ice poses logistical problems that are considered too challenging.  The Navy ice camp, if at all materializing, is most likely available too late in the season (and for too short a time span), and expected to pose additional logistical problems, unknown at this time.
 

4. Mercury speciation over sea ice

 (Steffen/Staebler/Netcheva/Lee/Sheppard/Bottenheim EC, Douglas (CRREL)

A three week intensive campaign will be staged to measure ozone and speciated Hg at different surfaces over frozen sea ice.  Snow, ice, brine and water samples will be collected (Tom Douglas) to investigate the interactions of mercury from these media to the air and from the air to these media.  A second speciation system (Tekran 2537A, 1130, 1135) to measure Gaseous Elemental Mercury (GEM), Reactive gas phase mercury (RGM) and mercury associated to particles (PHg) will be mounted on one of the OOTI sleds and transported to desirable locations, and the OOTI sled will be placed beside the mercury sled.  The mercury system will require about 3 kW power, which will be obtained form a portable generator.  For operation on the ice of the speciation unit, see photos. 

Summary of mercury systems to be brought to Barrow:
Mercury System #1

  • Located at/near the wannagans
  • UHP argon (3 T size bottles)
  • Requires power (3 x 15 amp circuits)
  • Will be totally self sufficient outside (see photo)
  • Some indoor space required to set up and warm up instruments prior to deployment
  • Inlet height ~15 cm or 3 m from snow surface

Mercury System #2

  • Located at lagoon or appropriate ice location
  • No requirement for housing during sample collection
  • Some indoor space required to set up and warm up instruments prior to deployment
  • Inlet height ~15 cm from ice surface
  • Requires 3000 W generator and fuel
  • UHP argon (2 T size bottles)
  • Skidoos to get back and forth
  • Sled for generator

Mercury System #3

  • Located with balloon system
  • UHP argon (1 T size bottle)
  • Indoor space for the instrument (sample line to be attached to the balloon)

SODAR on the ice near the Amundsen ice breaker, March 2008
SODAR on the ice near the Amundsen ice breaker, March 2008

OOTI sled operating on the ice near Kuujjuarapik in March 2008, sampling over frost flowers

Mercury speciation unit operating on the ice near the Amundsen ice breaker, April 2008.