cc: rbattarb@geography.ucl.ac.uk, k.briffa@uea.ac.uk, rbradley date: Mon, 19 May 1997 15:24:28 +0100 from: oldfield@pageigbp.unibe.ch (Frank Oldfield) subject: PEP III in the Implementation Plan to: gasse@geophy.geol.u-psud.fr Dear friends, It is my prilvilege and delight on this sunny Whit Monday afternoon to be finalising the text of our dear and much anticipated Implementation Plan. As one of the books I was obliged to learn my terrible french from in the 1940's said (for reasons I have never fully understood...it was sometimes hard to work out what Michel and Denise were getting up to... but the phrase sticks in the numbed and crumbling mind)... "Oh joie! Oh paresse!" There was a plan to put some stuff on Stream I into the Plan from the Beirville Meeting - it is even minuted in the Stellenbosch SSC notes. All I have is a Working Group report from Keith. I have created a new sub-heading ( STREAM I PRIORITIES) and used his text to put together a draft entry. In so doing I have deleted some bits that seem to be said elsewhere in the PEP III part of the Plan and I have changed odd bits where they need to be rephrased. Please can I have reactions from you all as soon as possible. Rick and Keith - does this still say what you mean and would you like to see it included? Francoise - est-ce que tu pense que ca sera bon de l'ajouter a ce qui est deje la? Y-a-t-il des idees dedans qui ne sont pas essentielles ou avec lesquelles tu n'est pas contente? (Et j'espere que ca va mieux pour toi). Please let me have your responses as soon as ever possible. I really must try to get this finalized before, like the Forth Bridge, the whole damn lot needs another coat of paint. ------------------------------------------------------------ STREAM I PRIORITIES Arisng from discussions at the September 1996 Bierville Meeting, the following priorities were identified:- * A major focus of PEP III Stream I research should be on establishing the degree to which 20th century climates are unprecedented. This must involve quantitative reconstruction of past mean climates on multi-decadal and century timescales as well as inter-annual variability and the frequency of extremes. * There remains a widespread preconception that the Little Ice Age and Medieval Warm Epoch were ubiquitous features of the climate history of the last two millennia. There is still a need to further clarify the definition of these concepts in terms of their character, extent and precise timing, even within Europe. More research is required to establish the extent to which the concepts of the Little Ice Age and Medieval Warm Epoch are valid or relevant in other areas of the transect. Future research must attempt to clarify whether, if real, these phenomena represent unique events within the last 2000 years, and, if possible, in the context of the Holocene as a whole. * Traditionally, high-resolution studies within the Stream I timeframe have been very much concentrated in the mid-to-high latitudes of the northern part of the PEP III transect. In part, this reflects genuine difficulty in locating datable, high-resolution records in low latitudes and in the African part of the transect.The existence of numerous, long tree-ring chronologies in Morocco is an important exception. Some potential for other dendroclimatological studies in north and east Africa has been clearly demonstrated and the future development of this potential should be explored. * Given the problems of identifying annually resolved palaeosources in Africa, there is a need to explore other less-well-resolved sources, particularly where they might be represented across wide areas of the transect. The concept of a specific research initiative aimed at exploring climate proxies in the sediments of a series of African crater lakes along the East African section of the transect is considered worthy of prioritisation and a Workshop in Ethiopia in November 1997 has been provisionally planned. * Even in Europe, there is important potential for identifying and processing historical and early meteorological records. Some palaeo-series, produced perhaps decades ago, now require updating. * More research is required in order to identify and gauge the significance of anthropogenic environmental disturbance and the implications for palaeoclimate estimates calibrated against modern climate data. * Archaeological data have been underutilised in a palaeoclimate context. Collaboration between archaeologists and palaeoclimatologists, especially in areas with a tradition of detailed high-resolution archaeological work and historical and palaeoclimate proxies, should be promoted. Several regions, such as in the Mediterranean and in monsoon areas (particularly in Egypt) and in the south of Africa, are potential foci for such efforts. * Intense attention to accurate chronology is encouraged in situations where absolute dating is not feasible. This might involve multiple dating proxies. * Work to establish a detailed network of tephra histories in the circum North Atlantic Region and the possibility of developing a widely applicable tephra chronology to provide fixed dating points for many less-well-resolved data sources is noted. * Studies within Time Stream I should not be constrained by the 2000 year limit if longer timescales within the Holocene can be embraced with equivalent precision and accuracy. -------------------------------------------------------------- Over to you, Frank