World Climate Research Programme (WCRP) Polar Climate Predictability Initiative (PCPI) (V. Ryabinin (WCRP) for PCPI Co-Chairs) Ted Shepherd (Department of Meteorology, University of Reading, UK; representing SPARC) Cecilia Bitz (Department of Atmospheric Sciences, University of Washington, USA; representing CliC) and

Motivation: 1)The both poles behaving differently, not much is explained reliably 2)Mounting evidence of the existence multi-scale long-term predictability associated with polar processes and climate change 3)Answers can be found only by a cross-cutting research, e.g. trends in SO ice linked to O 3 hole evolution (wrong?!), Sudden Stratospheric Warmings affect Atlantic Ocean overturning circulation, GHG build-up, ENSO effects, fresh water changes, etc., etc. PCPI The same feeling for polar regions predictability research as prior to the WCRP TOGA Project for El Nino – Southern Oscillation research

PCPI in WCRP + Co-sponsored activities and projects with: GCOS, GOOS, GTOS, WWRP, IGBP and its projects, IOC, SCOR, … + 4 project offices & 1 Support unit PCPI

Developments First ideas started in 2008 and a 2-year work resulted in the Bergen Workshop (October 2010), the idea of Initiative was supported by the community Draft implementation plan started at the Toronto workshop (April 2012) Six initiatives identified in 2012 Discussion at WWRP-PPP Steering Committee meeting in December 2012 identified three joint initiatives A good team of co-leads identified Intentions: there are lots of model intercomparisons and gathering of datasets that can inform the questions, but the approach is to see where new initiatives are needed. Milestone: a pan-PCPI workshop of PCPI component leads and other key people from 3-4 April 2014 in Boulder, USA. Important “Workshop on polar-lower latitude linkages and their role in weather and climate prediction” (Barcelona, December 2014), both PCPI and PPP involved PCPI

WMO GIPPS (G lobal I ntegrated P olar P rediction S ystem ) research on ice sheets and sea level WWRP Polar Prediction Project (PPP) Regional Grand Challenge PCPI Initiatives Cryosphere Grand Challenge Leads: Cecilia Bitz & Ted Shepherd Understand past polar climate variations, (paleo, up to 100 years) Assess reanalyses in polar regions Understand polar climate predictability on seasonal to decadal timescales Assess perfor- mance of CMIP5 models in polar regions Model error Understand how jets and non- zonal circulation couple to the rest of the climate system in the Southern Hemisphere Days -> Months -> Years -> Decades -> Centuries PCPI

Support PCPI will coordinate mostly electronically and through meetings of opportunity Some support funding available through WCRP and the Environment Canada Grant for GFCS (thank you!) WCRP Project scientist Dr Diane Pendlebury no longer available, but the International Coordination Office at AWI-Bremerhaven (PPP) will help Website to be hosted by CliC EC-PORS Actions suggested in EC-PORS-5/ INF. 13: to comment on the progress of PCPI to comment on the coordination and links between the WWRP PPPP and PCPI to provide feedback on the contribution of PCPI to GIPPS PCPI