lead fluxes andreas held, caroline leck, ian brooks, barbara brooks, sarah norris
Post on 24-Dec-2015
215 Views
Preview:
TRANSCRIPT
SOURCES
TRANSPORT DRY DEPOSITION
open sea sea-ice lead
TRANSFORMATION
surface albedo
cloud albedo
CCNscattering & absorption
WET DEPOSITION
Simplified Arctic Aerosol Life Cycle
Open Lead Flux System
1) Gill sonic anemometer
2) CLASP optical particle counter
(0.24 < Dp < 18.5 µm)
3) CPC 3760A condensation particle
counter (Dp > 11 nm)
4) LICOR 7500 CO2/H2O analyzer
5) MOXA dataloggerCLASP units
LiCOR 7500
sonicanemometer
Examine the capacity of the open leads to emit particles to the air by eddy covariance measurements:
fully battery operated (low power consumption)
located close to the ice edge ~2 m above the surface, near bubble camera site
Neutral Case
z/L=0z0=0.001 m, σv / u* = 2zm=1, 2, 3 m
wind
10 20 50 100 mPhoto: H.J. Zwally, NASA Goddard
Footprint Analysis of Open Lead Flux System
FSAM (Schmid, 1994)
Pu
mp
Sensing head
25 cm
• 16 channels - 0.24 to 18.5 m diameter• Flow rate 3 l/min – high sampling statistics allows 10 Hz temporal
resolution• Compact (25 x 8 x 6 cm) – allows collocation with sonic anemometer,
short inlet tube and low flow distortion, & installation in balloon instrument package and on buoy
CLASP Instrument
• Total particle number concentration for Dp > 11 nm
• Flow rate 1.5 l/min – good counting statistics
• 10 Hz sampling, but actual time response is slower
• Provides additional size bin from 10 nm to 240 nm in combination w/ CLASP
Condensation Particle Counter
Spray Sampler for Filter Collection and Electron Microscopy
Stockholm prototype:
• artificial bubble generation below water surface
• adjustable bubble diameter to generate film/jet droplets
• spray collection w/ filter sampler for off-line analysis
• spray collection on EM grid for electron microscopy
• free floating on water
• height adjustment of bubbler & sampler
top related