PAGES2K transregional teleconference 3/13/15 notes agenda: 1. (10min) Overview 1.1. Goal: planning: timeline.strategies to completion of PAGES2K projects. 1.2. Background: circulars since 2009 OSM (Oregon) and will include this week's teleconference report. 1.2.1. 9 regions: 8 continents + global ocean groups, each with leadership team and data manager 1.2.2. plus: transregional initiatives (listed on P2K webpages) 1.1.3. 2K coordinator group to facilitate interactions: Darrell, Hugues, Chris, Mike, (Lucien, Thorsten) 1.1.4. 2013 synthesis paper in Nat. Geosciences. 1.3. Room for improvement: "Phase 2": 1.3.1. Heterogeneity of approaches by region 1.3.2. Differences: arising from different strategies, or from real regional climatic change differences? 1.3.3. What are goals for transregional coordination? In other words: what are plans for regional hydroclimatic reconstruction, analysis and interpretation? How should these efforts be coordinated? 2. Timeline for PAGES2K phase 2: end of 2016 target for synthesis products (Fit to PAGES2k funding cycle and in time for next PAGES OSM in early 2017.) But this is a short time window, so we need to think about working toward specific attainable products by then. 3. Strategies: development of hydroclimate (HC) database 3.1. Africa2K (Brian Nash, representing): hydroclimate dataset 90% complete (~30 records), QSR special issue this spring; catalog observations, rather than significant new analysis. Once this is complete, further analysis will happen next, including contribution to a global hydroclimate synthesis. 3.2. EuroMed2K (Ulf Buntgen, representing): "both on track and far behind": mtg this week with Juerg Luterbacher, Jan Esper and Ulf Buentgen; focusing on Phase 1b product: T reconstruction, last millennium, for Europe. Once this is submitted, we will develop phase 2. Autumn mtg in Spain: better understanding: what is possible for hydroclimate reconstruction, last 2K, EuroMed sector. Collecting, archiving, making data available is a large task. Old World Drought Atlas is ready, not yet available (paper just submitted a few days ago; Ed Cook et al); this is a high skill and resolution benchmark for further work in HC reconstruction. What can we provide in addition? probably focusing on lower resolution phenomena; "tree-ring free" reconstruction or "surrogate"; key to success is quality and quantity of observations. Planning to keep time window open as long as possible for observational database collection/testing. So far from having something new for Europe/Med now. 3.3. South America (Ignacio Mundo, data manager, representing; leadership open): Las Cruces mtg this past year; discuss comparison of tropical and extratropical data; not much progress on collecting new observations since last year. HC reconstructions: South American Drought Atlas from tree ring data (Andes to Patagonia). Progress on that not specified, but Phase 1b T database contribution is complete. 3.4. Australasia (Joelle Gergis, Monday) 3.5. Arctic (Hans Linderholm, representing): short meeting + splinter mtg at EGU to discuss Phase 2. Paper planned to define hydroclimate in the Arctic: review observations, and see what can be done. Draft planned for early autumn. Drought atlas published for Fennoscandia; currently testing tree ring data for whole region. Data coverage means no whole-Arctic reconstruction; rather, regional reconstructions. Please join the splinter mtg at EGU. 3.6. Antarctic (Barbara Stenni, representing): some delay with temperature reconstructions using both high and low resolution records, but planned to have by end of year. HC data: not water stable isotopes, rather accumulation rate ~ [net] precipitation; and relationship between stable isotopes and snow accumulation rate is not straightforward. Published reconstruction for last 800y is a basis for the work. Length of records: no direct precipitation measurements of precipitation, so no calibration target. Plan for paper on precipitation (snow accumulation; led by M Frittati(sp?) and M Sigl), parallel to the end of 2016 deadline should be possible. About 70 records; most less than 500 years; others are up to 200y long; resolution up to seasonal deposition at continental edges; but for interior, lower resolution. More realistic HC database deadline: September rather than end of June. 3.7. Asia (Zhixin Hou, representing): Collecting data from the region for the past few months; China, India, Russia, Thailand. 70% about 300y long. Plans to have next (3rd) Asia2K workshop (next week, Japan): discussion of temperature reconstruction, details of approach; efforts to obtain additional data from primary sources being made. Plans for HC data collection? next week at the workshop. 3.8. Oceans (Belen Martrat, representing): Three points: (1) ocean2k will contribute to HC focus; (2) oceans group is relatively young; (3) Quality control is essential 228-->57 HR sites; many --> 57 LR sites; suggestions sent; (4) regional synergies important; (5) first ocean2k mtg to be held in Sept/Oct and help focus our Phase 2 efforts. 3.9. North America (Darrell Kaufman, representing): existing drought atlas data product; focus will thus be to study key intervals of droughts and pluvials, and use multiproxy database to evaluate the tree-ring-based reconstructions. Darrell's comments: original vision: a 2K book; but thinking has now focused on development of a special issue of a journal. Enthusiasm for open access outlet such as Climate of the Past, which includes discussion element. Timeline: open for contributions in June, and closing in December. Papers can thus be published as they come in. Ultimately a paper copy of the result could be printed. Flexible. Comments: (Brian Chase) Plans to assess observational synthesis at Afr2K mtg, within context of last millennium GCM simulations. 4. Discussion of the HC database: 4.1. (Darrell) What are the threads that run across all regions (even if HC is not a global reconstruction target)? Transregional initiatives. 4.2. (Darrell) Short term goal: global database of water isotopes in paleoclimate observations database. Can we pull together a dataset that is consistent across regions? What information is contained in the isotopic records? Metadata important here: accurate and precise representation of authors' interpretation of the data wrt environmental controls. Hopefully this is a relatively small and manageable moisture-relevant dataset. 4.3. (Darrell) Version 2 global T database: output shortly to be made available for quality control, metadata testing, planning and diagnostics. 4.4. (Darrell) product may not be able to do everything. Quality control may target-product sensitive. Discussion (HC data): (Brian) what isotopic data are available in Africa? Few. Some data are low resolution, and some data with ambiguous interpretation (temperature + moisture): representation problem across sites and observation types. So the strategy might not best leverage HC data for African region. (Darrell) isotopic data is intended to be the only observational target for HC database and analysis; just a framework for a transregional initiative. (Ulf) Not many European isotopic records, and not at high resolution; especially over the 2K interval. Data collection will be sensitive to choice of collection criteria. (Belen) isotopic data collection is possible from the oceans (?) (Hugues) timing: need data compilation first; use comparison with simulations to make interpretations (on broader scale). (Bronwen) isotopic records may be indicative of larger-scale behavior; isotope database might be a useful database; perhaps isotope database is not the best focus for a larger compilation. What would then be the best target for such a global compilation? (Lucien) HC variation is expressed differently across regions; so maybe allowing regional groups to proceed in a regionally-optimized way is best. (Darrell) Not clear what best targets for a global HC product or database should be. Wait on regional group results to see how to build a global synthesis? Hard to see that at the moment. But variables that integrate might be good places to start. Isotope dataset may lead to addressing a variety of new questions: comparison with isotope-enabled simulations, comparison with independent paleoclimate observations, ... Isotopic database/analysis might be an example of development of other transregional initiatives. (Bronwen) Synthesis paper in CP issue? (Lucien) Yes, could also be published elsewhere with broader audience. (Darrell) Yes, special issue should have a summary/overview. (Hugues) the introduction could be a review paper in the special issue. This could be a minimum synthesis output. Something more comprehensive could be done in a different journal, depending on what emerges. Concuding remarks (Darrell) teleconference works; we should do this more often. Please send emails with comments/suggestions to Lucien for compilation and incorporation into the circular. Possible action items: (1) global water isotope database, teleconference to determine criteria, quality control, metadata. Recording will be available via podcast and chat window capture will be available.