The Polar Prediction Project and the Year of Polar Prediction Photo: G. Dieckmann, AWI Francisco Doblas-Reyes on behalf of the PPP steering group and ICO ICREA, IC3, BSC WGSIP17, Norrköping 14 September 2014

PPP mission statement Promote cooperative international research enabling development of improved weather and environmental prediction services for the polar regions, on time scales from hourly to seasonal - Two aspects that reflect a change of WWRP: Environmental prediction, not just weather, e.g. sea ice Beyond the medium range -> bridge to WCRP Kind of legacy of both (i) the International Polar Year (IPY; 2007/2008) though more focussed on prediction and (ii) THe Observing system Research and Predictability Experiment (THORPEX) Apart from carrying on momentum from IPY and THORPEX, why PPP? -> next slide Suppl. info: October 2009: CAS recommends the establishment of a THORPEX Polar Research project November 2010: EC-PORS formulates plans for GIPPS, of which PPP is the component up to seasonal and PCPI is the component beyond seasonal

Synop, AIREP, DRIBU, TEMP and PILOT Why? 1. Significant gaps in the polar observing systems - Here only conventional data, but also true for satellite data and ocean data (Argo!) - Obs. Difficulties: Harsh environment, sea ice prevents Argos, weak thermal and optical contrast between ice and clouds Synop, AIREP, DRIBU, TEMP and PILOT Polar data coverage of conventional observations in the ECMWF operational analysis on 1 January 2012 P. Bauer (ECMWF)

Why? 1. & 2. result in deficient forecasts Potential versus realized seasonal sea-ice forecasting skill SIPN Sea Ice Outlook September September sea-ice extent (106 km2) The left figure shows that current forecasts of year-to-year fluctuations of the September sea-ice extent from 1st July have virtually no skill The right figure, based on ensemble-simulations in the "perfect-model" framework, indicate that such predictions could in principle be much more skilful. initialized 1st July Tietsche et al. 2014 (modified) Stroeve et al. 2014

Photo by Chilean Navy/Reuters Why? 3. Arctic opening Some statements from the report: The Arctic is likely to attract substantial investment over the coming decade ($100 bn) The environmental consequen-ces of disasters in the Arctic are likely to be worse than in other regions Significant knowledge gaps across the Arctic need to be closed urgently With opportunities come risks! Imagine oil spill Show sinking ship (2007 off Antarctica) Improved environmental predictions urgently needed to meet this growing demand. Suppl. Info: LLOYDS is a think tank associated with big insurance companies Photo by Chilean Navy/Reuters

4. Antarctic Logistics and Safety Why? 4. Antarctic Logistics and Safety Antarctica is a harsh environment Logistical support for research is expensive – more accurate predictions are needed Typical cost is USD100k if a flight from NZ to McMurdo Station has to turn around because of unforecast poor weather at McMurdo Tourist expeditions are vulnerable to weather and ice With opportunities come risks! Imagine oil spill Show sinking ship (2007 off Antarctica) Improved environmental predictions urgently needed to meet this growing demand. Suppl. Info: LLOYDS is a think tank associated with big insurance companies Photo: Andrew Peacock / www.footloosefotography.com

Why? 5. Potential for advanced predictions in middle latitudes Day 1-5 Jung et al. (2014), Geophys. Res. Lett. In these experiments (atmosphere-only), the atmosphere was nudged towards the actual evolution (reanalysis) only around the North Pole (solid circle) Colours show the percentage forecast error reduction Error strongly reduced in the Arctic (which is trivial because of the nudging there), but error reductions are also found in mid latitudes, in particular over the continents Note that this is a conceptual upper limit of the effect because actual improvement of polar forecasts will never be as good as nudging towards the actual evolution!

What? Source: PPP Implementation Plan Most concise summary is the mission statement -> now more concrete: make substantial progress in these areas Not very different from lower latitudes, but aspects within subjects quite different (as seen in previous slides): sea ice one of main focusses (environmental forecasting!) emphasis on COUPLED system (incl. data assimilation), ensemble methods: (sufficient spread? Pert. Methods focused on lower latitudes, e.g. moist convection, barocl. instability, ...) Source: PPP Implementation Plan

How? ★ Develop Strong Linkages with Other Initiatives ★ Strengthen Linkages Between Academia, Research Institutions and Operational Centres ★ Establish and Exploit Special Research Datasets ★ Link with Space Agencies ★ Promote Interaction and Communication Between Research and Stakeholders ★ Foster Education and Outreach ★ Link with Funding Agencies (already mentioned above) Members from all realms on board of steering group; related to idea of "seemless prediction" List compiled with existing data sets that need to be exploited; new (obs AND sim) shall be generated, GTS ... Mainly via link to Polar Space Task Group (successor of IPY-Space Task Group) Stakeholders = "parties interested in success of project"; e.g. northern communities, indigenous people, private sector, governments Summer schools, webinars, collab. with APECS / website info, collab. with Polar Educators International Europe, NSF/ONR/NOAA (Thomas Jung recently in Washington); maybe there will be calls which explicitly mention of PPP/YOPP

Year of Polar Prediction MOSAiC - Long year ; core period from mid-2017 to mid-2019 - Example 1: Intensive observing periods: (i) more observations needed in general, additional value having them in the same time (ii) snapshot for higher-quality REANALYSIS (ERA-YOPP) -> useful for verification, process understanding, ... (iii) enables judgement upon value of certain obs for forecasting (OSEs, ie data denial experiments) (iv) aligned with planned MOSAiC campaign (where Polarstern drifts through Arctic) Example 2: Dedicated model experiments: OSSEs / OSEs; in NWP context OSSEs are common practice for satellite planning; autonomous gliders under sea ice could be a target in the context of YOPP Example 3: Verification effort: baseline skill comparison between current operational 7-day sea-ice forecasts (US Navy; Env. Can.; MyOcean (Europe)) currently being discussed

S2S and PPP ★ Joint meetings already took place ★ PPP requests for additional high-latitude variables in the S2S archive ★ Possibility of intense reforecast period during the YOPP IOP ★ What role for WGSIP and DCPP? (already mentioned above) Members from all realms on board of steering group; related to idea of "seemless prediction" List compiled with existing data sets that need to be exploited; new (obs AND sim) shall be generated, GTS ... Mainly via link to Polar Space Task Group (successor of IPY-Space Task Group) Stakeholders = "parties interested in success of project"; e.g. northern communities, indigenous people, private sector, governments Summer schools, webinars, collab. with APECS / website info, collab. with Polar Educators International Europe, NSF/ONR/NOAA (Thomas Jung recently in Washington); maybe there will be calls which explicitly mention of PPP/YOPP

Organization of PPP-related events Expert meetings Conferences and workshops Workshop "Polar-lower lat. linkages" Barcelona Dec. 2014 Panel discussions Townhall meetings +++ slides and audios available at polarprediction.net +++ Photos by N. Gordon