Large-scale climate variability in Antarctica and the Southern Ocean over decades to centuries, and links to extra-polar climate

This joint PAGES & WCRP Research Program Polar Climate Predictability Initiative workshop will be held at the Scripps Institution of Oceanography in La Jolla, California. The objective of the workshop is to develop an assessment of large-scale patterns of Antarctic climate variability over the last decades to centuries, and the extrapolar-polar teleconnections, by combining proxy records, historical data, modern instrumental records, and model results.

Overview and aims

Numerical models indicate that the high latitudes of the Southern Hemisphere experience significant multi-decadal variability. Unfortunately, instrumental records are of insufficient duration to characterize this variability. For instance, the Southern Annular Mode (SAM), which describes the leading mode of variability in atmospheric circulation in the Southern Hemisphere, can be well estimated since the International Geophysical Year of 1958, when systematic observations began at Antarctic scientific stations. It has however been estimated through sparse observations and reanalysis back to the 1870s.

To understand the changes, improved analysis of the full climate system, including sea ice, sea surface temperature, Antarctic temperatures, and ocean circulation, as well as non-annular modes of atmospheric circulation such as the Amundsen Sea Low, and the emerging important links of high latitude climate to extra-polar latitudes are needed. These present a greater challenge, with systematic measurements beginning in 1979 with the advent of satellite measurements/observations, and oceanic variables such as temperature and salinity profiles with Argo floats in ~2004.

However, there has not been a concentrated effort to evaluate paleoclimate proxy data in the Southern Hemisphere in combination with older instrumental data and records from ships’ logs to provide best estimates of past climate, nor has there been a significant effort to characterize the non-annular components of historic variability.

The workshop will include atmospheric scientists, oceanographers, and cryosphere specialists and it will bring together expertise in paleoclimate, in historic data, and in the modern instrumental record, from both the polar and extrapolar communities. This will provide an opportunity to connect the recent past with the paleo record and to compare model behavior with historic and proxy data.

The outcome of the workshop will be an updated assessment of the historic instrumental and proxy data available to estimate past climate, and of polar-extra polar linkages. The workshop will provide a forum for exploring possible improvements in estimates of changes at the surface (mainly temperature and sea ice extent), of the SAM, and of the non-annular patterns of large-scale climate variability.

In order to make the workshop as productive as possible, one or two telecons will be held in the months leading up to the workshop in order to identify key variables that we'll want to examine during the workshop.  A planned outcome of the workshop will be a journal publication presenting our assessment.

Registration

A limited number of places are available. Limited support for travel is available for early career scientists and scientists from developing nations, who are especially encouraged to apply.

If you are interested in participating, please send an email before September 15, including information on the four items below, to Hugues Goosse (hugues.goosseuclouvain.be (hugues[dot]goosse[at]uclouvain[dot]be)):

a) Name, and affiliation

b) Your position (in particular if you are an early career scientist, i.e. PhD student or PhD completion less than 5 years ago).

c) Why would you be interested in participating and/or contributing to the workshop (5 lines max).

d) Would you require funding, or would you be able to participate in the workshop without support for the meeting organization?

All applications will be reviewed, taking into account the potential contribution of each applicant to the workshop and availability of funds, and applicants will be informed of the outcome before October 6.

Coordinators

Sarah Gille (Scripps Institution of Oceanography) sgilleucsd.edu (sgille[at]ucsd[dot]edu)

Julie Jones (University of Sheffield) julie.jonessheffield.ac.uk (julie[dot]jones[at]sheffield[dot]ac[dot]uk)

Hugues Goosse (Université catholique de Louvain) hugues.goosseuclouvain.be (hugues[dot]goosse[at]uclouvain[dot]be)