300 likes | 427 Views
Antarctic Airborne Measurements. Tom Lachlan-Cope (Alexandra Weiss, Russ Ladkin) British Antarctic Survey. Instruments. Temperature + Humidity Radiation Turbulence (wind) Fast Temperature, Humidity and CO2 Cloud probe Aerosol Camera Laser Altimeter Surface temperature.
E N D
Antarctic Airborne Measurements Tom Lachlan-Cope (Alexandra Weiss, Russ Ladkin) British Antarctic Survey
Instruments • 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 • 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 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
Flight track Peninsula
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
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.