Surface Layer Turbulence and Aerosol Profiles During MAPTIP
conference paper
The Naval Postgraduate School (NPS) and the TNO Physics and Electronics Laboratory (TNO-FEL) deployed in situ sensors near and on Meetpost Noordwijk (MPN) during MAPTIP to describe the surface layer processes and also to evaluate models for near-surface aerosol profiles. Vertical profiles of aerosol counts were measured on the MPN tower by TNO-FEL with Rotorod impaction samplers. The aerosol distribution measurements were made for l0 radius bins, with centered radii ranging from 6.5 to 75 pm. Atmospheric surface-layer turbulence and stratification were measured by NPS from an instrumented buoy that was located a short distance from MPN. Existing models relate aerosol profiles to source, sink, and turbulent transport processes. The assumed source process is bursting air bubbles at the surface. The removal processes are turbulent deposition and gravitational fallout. Turbulent transport is described by the friction velocity and the near-surface stratification. The combined buoy and MPN data sets are shown to provide valuable descriptions of surface layer properties during the variable period from 26 October through 3 November. Results from eleven profile sampling periods were compared with model predictions for which buoy measured parameters and aerosol sizes were inputs. The predicted concentration often decreased more with height than observed. This is believed due to the coastal input to the aerosol source since advected aerosol would reduce influences on gradient of bubble production at the surface.
TNO Identifier
94803
Publisher
AGARD
Source title
AGARD Conference Proceedings on Propagation Assessment in Coastal Environments - Paper presented at the Sensor and Propagation Panel Symposium, held in Bremerhaven, Germany, 19-22 September 1994
Place of publication
Neuilly-sur-Seine
Pages
25/1-25/9