Antarctic Airborne Measurements Tom Lachlan-Cope (Alexandra
Weiss, Russ Ladkin) British Antarctic Survey
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Instruments Temperature + Humidity Radiation Turbulence (wind)
Fast Temperature, Humidity and CO2 Cloud probe Aerosol Camera Laser
Altimeter Surface temperature
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Human activity responsible for Larsen Ice Shelf collapse Figure
1. Difference between positive and negative summer SAM 10-m wind
field There is a significant recent trend in the Southern
Hemisphere Mode (SAM) towards its positive phase in summer: result
is 20% stronger circumpolar westerly winds. This reduces the
blocking effect of the Peninsula, resulting in greater frequency of
advection of relatively warm maritime air across the northern
Peninsula from west to east (Fig. 1). A combination of a
climatological temperature gradient across the barrier and the
formation of a fhn wind (warm and dry) on the lee side causes a
summer temperature sensitivity to the SAM that is three times
greater east of the Peninsula than to the west. There is a
significant recent trend in the Southern Hemisphere Mode (SAM)
towards its positive phase in summer: result is 20% stronger
circumpolar westerly winds. This reduces the blocking effect of the
Peninsula, resulting in greater frequency of advection of
relatively warm maritime air across the northern Peninsula from
west to east (Fig. 1). A combination of a climatological
temperature gradient across the barrier and the formation of a fhn
wind (warm and dry) on the lee side causes a summer temperature
sensitivity to the SAM that is three times greater east of the
Peninsula than to the west.
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Peninsula Flight track
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Ascent Descent
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Sea Ice Formation Air/sea/ice interaction Boundary layer
modification Formation of deep ocean currents
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IRT (surface Temp) Air Temperature
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CONVECTIVE HEAT TRANSFER OVER THIN-ICE COVERED COASTAL POLYNYAS
E. K. Fiedler, T. A. Lachlan-Cope, I. A. Renfrew, and J. C. King
JGR Oceans - inpress
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Clouds
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Increase in Cloud Condensation Nuclei Increased CCN mean more
smaller cloud drops not more cloud. More smaller drops mean
increased albedo (clouds are whiter). More smaller drops mean less
precipitation Less precipitation mean clouds last longer So in the
end more clouds perhaps.
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What do we want to know Are Antarctic clouds similar to
mid-latitude clouds? How can we represent Antarctic Clouds within
climate models?
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This Season ICEBELL Aircraft measurements of sea ice coincident
with ship measurements Scanning laser altimeter fitted Offcap
Measurements of cross Peninsular flow Aircraft and ground based
measurements Cloud measurements
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Future work Arctic studies Combined ground based and aircraft
measurements of aerosols and clouds. Using BAS Twin Otter and NERC
BA 146 Aerosol inlet fitted to Twin Otter.