Is the Halley temperature record homogeneous?

Add to your list(s) Download to your calendar using vCal

• Prof. John King, British Antarctic Survey
• Friday 23 October 2020, 14:00-15:00
• https://ukri.zoom.us/j/94856318028?pwd=UHJCckFwNUlVMmZJaURCQlF4SjBKdz09; .

If you have a question about this talk, please contact Dr Hua Lu.

This talk has been canceled/deleted

Commencing in 1956, observations made at Halley Research Station provide one of the longest continuous series of near-surface temperature observations from the Antarctic continent. The record does not, however, come from a single location but is a composite of observations from a sequence of seven stations, all situated on the Brunt Ice Shelf, that range from around 10 km to 50 km distance from the ice shelf coast. Until recently it was generally assumed that temperature data from all of these stations could be combined into a single composite record with no adjustment. In this talk I will report on recent research that suggests that this assumption of homogeneity is incorrect. Application of an objective statistical change-point detection algorithm indicates that there is at least one sudden downward jump in temperature associated with relocation of the station, which is large enough to introduce a spurious cooling trend into the composite record. Analysis of observations from a network of automatic weather stations and data from a run of a high-resolution regional atmospheric model confirm the existence of mean temperature gradients across the ice shelf which are large enough to explain the jumps seen in the record. These temperature gradients are largely driven by the advection of maritime air masses across the cold surface of the ice shelf. I will discuss the implications of these findings for local and regional climate studies that make use of the Halley record and will consider whether it might be possible to create a homogenised record.

This talk is part of the Atmosphere-ICE-Climate Seminar, Bristish Antarctic Survey series.

This talk is included in these lists:

This talk is not included in any other list

Note that ex-directory lists are not shown.