Extended Abstract (92K)P2.10
Boundary layer profiles of aerosol size distribution obtained by kites and a tethered balloon during the Arctic Ocean Expedition (AOE-2001)
Michael L. Jensen, CIRES/Univ. of Colorado, Boulder, CO; and C. Leck, A. Targino, B. Wehner, C. Fischer, and E. Swietlicki
The remote summer Arctic provides a unique environment to improve our understanding of the cloud mediated effect of natural aerosol on climate. A Tethered Lifting System (TLS) developed by researchers at the Cooperative Institute for Research in the Environmental Sciences (CIRES) at the University of Colorado was used to profile the boundary layer and lower troposphere during the Arctic Ocean-2001 expedition aboard the Swedish icebreaker Oden. Measurements were made from July through August, both from the pack ice during two short-term measurement stations and primarily during a three-week drift when Oden was anchored to an ice floe located close to the North Pole.
The TLS incorporates both parafoil kites and aerodynamic tethered balloons as lifting platforms for complementary wind regimes to enable operations in winds from 0 to 20 m s-1. A 1-kW electric winch was used to raise and lower the TLS platforms and instrument packages from the surface to over 2000 m. Power for the winch was provided by either a direct AC line from the icebreaker or from a series of car batteries. Over 3000 m of braided Vectran was used as the tether, providing a breaking strength over 400 kg in a diameter of less than 2.5 mm. Tether icing occurred on occasion and was manually removed from the tether as it was reeled in, proving to be a nuisance, but by no means a "show-stopper".
Over 50 profiles of aerosol concentration were made using a modified TSI PortaCount+ condensation particle counter (CPC). The CPC was modified to automatically switch between four inlets with varying numbers of diffusion screens (TSI Particle Size Selectors) to obtain a rough size distribution from 20 nm to over 1 mm in diameter in addition to the total aerosol concentration.
Results of the aerosol measurements, as well as, concurrent profiles of basic meteorological variables are presented for both fair weather and cloudy conditions. Comparisons of the TLS-borne profiles with those from CPC systems flown onboard an AS 350B Equrille helicopter will also be shown.
Poster Session 2, Observational Methods
Monday, 15 July 2002, 2:00 PM-2:00 PM
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