GrISSMB SheffieldMtg2015 GroupPhoto3Greenland Ice Sheet International Workshop Group Photo, May 2015, Sheffield, UK

-Contributed by Ed Hanna and Amy Jowett

Seventeen glaciologists and climatologists met in Sheffield for a two-day international research workshop on 19/20 May on how we can best improve the representation of Greenland Ice Sheet surface mass balance (SMB) in computer models of climate change. This is a challenging but exciting prospect as we attempt to model SMB, which equals net snowfall minus snow/ice meltwater losses, occurring over an ice mass with the combined surface area of France, Germany Italy and Spain.

The event was sponsored by the Climate and Cryosphere project of the World Climate Research Programme (WCRP CliC) and by the Ice Sheet Mass Balance and Sea Level working group (ISMASS) that is co-sponsored by CliC. Participating scientists came from several different countries including the the UK, Netherlands, Belgium, Denmark, USA – including representation from NASA – and Chile. The delegates included representation of all the SMB models used in the recent Intergovernmental Panel on Climate Change’s (IPCC) Fifth Assessment Report (Working Group I, Chapter 13 on Sea Level Change).

There is still very significant disagreement in the amounts of snowfall and meltwater runoff simulated by the different SMB models, and so we aim to reconcile model differences through a more thorough and detailed comparison of output from the different models than has previously been undertaken. The workshop also addressed the important question of where there are gaps in information from weather stations and ice-core data which are crucial for validating SMB models over Greenland.

It is anticipated that the SMB model intercomparison project and improvements promoted by this workshop will result not only in a dedicated peer-reviewed journal publication significantly advancing the science within the next 6-12 months but will also feed directly into improving estimates of the contribution of the Greenland Ice Sheet to global sea-level rise, to be reported in the next IPCC report around 2020. Apart from one and a half days of talks and discussion held in the Ron Johnston Research Room, the workshop featured a brief excursion to our Bradfield Environmental Laboratory on the second afternoon (when the showers held off!), as well as a workshop dinner in a traditional Sheffield pub. A great time was had by all.

Download the Draft ACTION PLAN arising from GrIS SMB modelling/model validation CliC/ISMASS Sheffield workshop here.

The full report of the workshop is available here.

Read more about the workshop here.