Download Antarctic airborne measurements

Antarctic Airborne
Measurements
Tom Lachlan-Cope
(Alexandra Weiss, Russ Ladkin)
British Antarctic Survey
Instruments
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Temperature + Humidity
Radiation
Turbulence (wind)
Fast Temperature, Humidity and CO2
Cloud probe
Aerosol
Camera
Laser Altimeter
Surface temperature
Human activity responsible for Larsen Ice Shelf
collapse
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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.
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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).
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A combination
of
a
climatological
temperature gradient across the barrier and
the formation of a föhn 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.
Figure 1. Difference between
positive and negative summer SAM
10-m wind field
Peninsula
Flight track
Ascent
Descent
Sea Ice Formation
• Air/sea/ice interaction
• Boundary layer modification
• Formation of deep ocean currents
IRT (surface Temp)
Air Temperature
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
Clouds
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.
What do we want to know
• Are Antarctic clouds similar to mid-latitude
clouds?
• How can we represent Antarctic Clouds within
climate models?
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
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.