date: Fri, 8 Aug 2003 12:25:43 +0100 (BST) from: "Ian Harris (Harry)" subject: RE: FW: HOLSMEER: Data Please! to: Keith Briffa Keith, Draft response to Roland. D'you think it's a bit harsh? Harry Hi Roland, Yes, we have copies of the paper. In our view it does not impinge on the Holsmeer project work. We've tried to make it clear in meetings that correlation with the NAO is widespread, and that the only deduction to be made from a strong correlation with the NAO is that the measured process is affected by the weather. The main thrust of this paper is that by calculating non-hydrostatic sea levels, the effects of wind can be decoupled from the effects of pressure. They can then determine the sensitivity of sea level to either, on a spatial basis. I hope that sets your mind at rest :-) Cheers Harry On Tue, 22 Jul 2003, Roland Gehrels wrote: > Hi Harry > > Have you seen this paper? > > Cheers, Roland > > > > GEOPHYSICAL RESEARCH LETTERS, VOL. 30, NO. 7, 1403, doi:10.1029/2003GL017041, 2003 > > Sea-level dependence on the NAO over the NW European Continental Shelf > > S. L. Wakelin, P. L. Woodworth, R. A. Flather, and J. A. Williams > > Proudman Oceanographic Laboratory, Bidston Observatory, Birkenhead, > Merseyside, UK > > Abstract > > [1] The connection between changes in the North Atlantic Oscillation (NAO) and the sea level over the northwest European continental shelf is investigated for the period 1955–2000 using a two-dimensional model of tides and storm surges. There is a clear spatial pattern in the correlation between sea level and the NAO on a winter-mean timescale. Correlations are positive (>0.8) in the northeast and negative (<-0.7) in the south. The sensitivity of the sea level to the NAO is strongest in the southern North Sea (up to 96 mm per unit NAO index), where most of the sensitivity is present also in the non-hydrostatic component of sea level. The relationships are validated using observed data recorded at coastal tide gauges. > > Received 3 February 2003; accepted 11 March 2003; published 10 April 2003. > > Index Terms: 4552 Oceanography: Physical: Sea level variations; 3339 Meteorology and Atmospheric Dynamics: Ocean/atmosphere interactions (0312, 4504); 4215 Oceanography: General: Climate and interannual variability (3309). > > -----Original Message----- > From: Ian Harris (Harry) [mailto:I.Harris@uea.ac.uk] > Sent: Mon 30/06/2003 11:43 > To: Roland Gehrels > Cc: > Subject: Re: FW: HOLSMEER: Data Please! > > > > Hi Roland, > > On Fri, 27 Jun 2003, Roland Gehrels wrote: > > > Dear Harry > > > > Just realised we haven't discussed this last email I sent, perhaps it > > got lost. Any comments/ideas? > > Politely put ;-) > > > Cheers, Roland > > > > > > -----Original Message----- > > From: Roland Gehrels > > Sent: 16 April 2003 11:52 > > To: 'Ian Harris' > > Subject: RE: HOLSMEER: Data Please! > > > > > > Dear Harry > > > > I am still waiting for dates from Oban and Aarhus, so can't really say > > when I can provide plots. Once I have the dates sorted I will send you > > the four sea-level records from the saltmarsh sites (mean tide level > > height plotted against calendar years for the last 2000 years). > > Great. > > > In Nice there was a group from Southampton (Mike Tsimplis and others) > > who were doing extensive work on the influence of the NAO on North > > Atlantic sea level. There were 92 tide-gauge records in their analyses > > I think. Are you familiar with that work? I didn't have a chance to > > speak to them as the authors never seem to be present at their > > posters. But I am a bit concerned that we are not re-inventing the > > wheel.... > > I'm not aware that the major thrust of Holsmeer is to establish links with > the NAO, so I'm not overly worried. I'll pass your concerns on to Phil & > Keith as they may have a more political perspective ;-) > > > As for the analyses you did in November, I am sorry I haven't given > > you much feedback yet. The correlation with winter sea levels seems > > very strong. This work is useful when it comes to writing up the > > coastal hazard prediction section for the project. It will tell us > > something about possible increase of flooding frequencies if NAO > > variability is going to be more extreme. My concern is that the salt > > marsh does not record monthly sea levels - it would be more > > decadal-type fluctuations. I suppose if all the sedimentation takes > > place in the winter time the correlation would be useful but it is > > more likely that sedimentation is very slow and more or less > > continuous from year to year. The correlation between the NAO and > > annual sea levels for Cascais and Reykjavik seems more relevant for > > the salt-marsh reconstructions. Are those correlations (0.33 and > > -0.34) significant? Have you come up with anything when you look for > > decadal-scale patterns and lead/lags? > > I've not addressed any of these issues yet; but I've put them in the list. > > > Let me know what you think and whether I can be of any help > > I'll be sure to! > > Cheers > > Harry > > > -----Original Message----- > > From: Ian Harris [mailto:i.harris@uea.ac.uk] > > Sent: 15 April 2003 17:32 > > To: James Scourse; Graham Forsythe; Phil Jones; Roland Gehrels; Bill > > Austin; Tracy Shimmield; Jon Eiriksson; Dierk Hebbeln; Jan Backman; Hans > > Petter Sejrup; Fatima Abrantes; Guillermo FrancZs-Pedraz; Karen Luise > > Knudsen > > Subject: HOLSMEER: Data Please! > > > > > > Dear Partners, > > > > Dr Phil Jones informs me that at the recent EGS Conference in Nice, it > > was decided that CRU would be inundated with data, both instrumental > > and proxy, from all Holsmeer partners, the better to fulfil our > > obligations under Workpackage 4. We will compare neighbouring proxy > > series with each other and with instrumental data, and provide suitable > > plots for the Delmenhorst meeting. > > > > Please could you all reply to this letter, giving me an idea of what > > you will be able to provide and when you will be able to provide it. > > > > As usual I will attempt to decode any data format but my preference is > > for space-, tab- or comma-separated values in a text file. > > > > I do look forward to hearing from you and trust you are all in fine > > health. > > > > Cheers > > > > Harry > > Ian "Harry" Harris > > Climatic Research Unit > > University of East Anglia > > Norwich NR2 4HG > > United Kingdom > > > > > > -------------------------------------------------------------------------- > Ian Harris ("Harry") > Climatic Research Unit > University of East Anglia > Norwich NR4 7TJ > Tel 01603 593818 > Fax 01603 507784 > -------------------------------------------------------------------------- > All opinions stated are those of the author and do not necessarily reflect > those of the Climatic Research Unit or of the University of East Anglia. > -------------------------------------------------------------------------- > > > > > -------------------------------------------------------------------------- Ian Harris ("Harry") Climatic Research Unit University of East Anglia Norwich NR4 7TJ Tel 01603 593818 Fax 01603 507784 -------------------------------------------------------------------------- All opinions stated are those of the author and do not necessarily reflect those of the Climatic Research Unit or of the University of East Anglia. --------------------------------------------------------------------------