cc: <j.haighatXYZxyzac.uk>, <email@example.com>, <k.briffaatXYZxyz.ac.uk>
date: Fri, 01 Nov 2002 14:17:26 +0000
from: "Rapid Rapid" <RAPIDatXYZxyz.nerc.ac.uk>
Dear Dr Manning
Please find below two further referee reviews on your research grant proposal (at last!)
I apologise for the tight deadline, but I would be grateful if you could respond to the comments by 8 November.
The entire proposal is very well written, clear and highly sophisticated. The author and the coauthors are all brilliant and outstanding researchers who understand their specific topics. The consortium includes a large group of internationally recognised researchers with expertise across a wide range of climate related disciplines and paleo-record. Their results proposed will lead to significant and novel results and insights with direct relevance to the RAPID programme's aim and objectives. The results will give a better view into the connection between the sun and the climate for the last centuries and even millennia on different time scales and for different regions. It combines field work, measuring high-precision 14C datasets, dendroclimatological analysis and comparison work as well as GCM and carbon cycle investigations. This is a very nice combination.
In my opinion, the questions and hypotheses are clearly formulated.
The following points are suggests and comments on parts of the proposal and not necessarily weak points. The authors may consider these points
On page 2, first para, the authors state that eastern/southern margin of the European-Mediterranean region is a gap with little data in total, and nothing beyond the last few hundred years. In fact there IS a lot of climate information, not only natural proxies based but also from a huge amount of historical documentary evidence. For instance Xoplaki et al. (2001) give an overview of the different sources and potential of these information for the southern Balkans and eastern Mediterranean and provide monthly temperature and precipitation indices for the Maunder Minimum period. The also discuss extremes and the impact of climate on socio economy in the area. In addition, the studies of Grove (2001) and Grove (2001) provide climate evidence from the Mediterranean for the last few centuries. For the entire Mediterranean land areas, there are temperature and precipitation reconstructions on a 0.5x0.5deg grid over land areas available, covering a large part of the LIA (monthly back to AD 1659 and seasonal back to AD 1500) (Luterbacher and Xoplaki, 2003). Single grid points or spatial averages can be obtained. The authors further discuss the reliability of the reconstructions and relate them to independently reconstructed NAO indices. These data would be available on request and could be used for verification purposes (page2, 2nd para of the proposal; ..provide a high-resolution paleoclimatic record) or even be related to solar forcing estimated by the authors.
It is not clear whether the authors assume a priori colder conditions during the so-called LIA in the (eastern part of the) Mediterranean or if it based on the literature (in fact it is doubtful that it was from the 14th to the 18th century, the onset of the so-called misleading term LIA is geographically different, see Grove, 2001)? As discussed in several papers, such as in Xoplaki et al. (2001; and references therein), Grove (2001 and references therein), Grove (2001 and references therein) and Luterbacher and Xoplaki (2003 and references therein) there were not lower temperatures throughout the LIA. In addition, there are spatial differences over the area through time.
It is also not entirely clear how the authors define the eastern Mediterranean. Is it Turkey alone, or does it include also Syria, Israel, Palestine, Lebanon, Cyprus, Jordan? In parts of their proposal they mention new tree-ring data from Lebanon and Cyprus.
The authors mention that the Turkish data will reveal a key resource for their analysis. The authors might think of investigating first based on instrumental data, how representative Turkish temperature and or precipitation is in terms of the eastern Mediterranean, entire Mediterranean and Europe. There are many studies from Turkish and Greek researches dealing with the connection between temperature/precipitation and atmospheric circulation based on 20th century data.
In addition, it would be of importance to consider also other atmospheric circulation indices except for the NAO/AO. Usually, people relate negative NAO to wet and cool Mediterranean conditions and vice versa. However, there are big spatial differences and this simple statement may not hold in different parts of the Mediterranean. For instance, in the PhD of Xoplaki (2002; PhD theses, available through http://sinus.unibe.ch/klimet/docs/phd_xoplaki.pdf) there are different correlation maps between winter temperature and precipitation over the entire Mediterranean with various circulation indices. These maps would also be available for the other seasons. For instance, she points to the fact, that for Turkish winter temperature, the EATL/WRUS pattern according to Barnston and Livezey (1987) seem to be as important as the NAO/AO. Depending on the climate variable, season and area, other circulation pattern than the NAO/AO might be of importance too to consider. At least for the last 500 years, such reconstructions (circulation indices and entire grids) exist (Luterbacher et al. 2002ab).
Page 3, first para: What is meant with ultra-high-resolution level?
Page 3, second and third para as well as page 1, second last para: I am wondering why the authors define the LIA AD 1750-1350, there is no reference for this (see above). At least in Europe, it seems that the 'LIA' lasted at least until 1850.
Page 3: Do the Turkish trees show a temperature or precipitation signal or both?
Page 3, 2nd last line: To my knowledge, regular temperature and precipitation records from Turkey begin at the end of the 1920s.
The authors may say something on the uncertainty of their reconstructions, how they intend to calculate them and how they may influence the sun-climate calculations.
Page 6, second para: It will be not an easy task to draw any conclusions from surrouning stations in Turkey to elevated areas. It would be helpful to study the different publications on Turkish temperature and precipitation (e.g. T�rkes, 2003)
Data Management and Dissemination:
It would be nice if the authors would submit the data to the international tree ring data bank and related institutions. Once the results and data are published, they should be open for free access.
Barnston, A. G. and Livezey, R. E., 1987. Classification, seasonality and persistence of low frequency atmospheric circulation patterns. Mon. Wea. Rev., 115, 1083-1126.
Grove, J. M., 2001: The Initiation of the "Little Ice Age" in Regions Round the North Atlantic. Climatic Change 48: 53-82.
Grove, A.T., 2001: The "Little Ice Age" and its Geomorphological Consequences in Mediterranean Europe. Climatic Change 48: 121-136.
Kadioglu, M, 1997: Trends in surface air temperature data over Turkey. Int. J. Climatol. 17:511-520
Luterbacher, J., Xoplaki, E., Dietrich, D., Jones, P.D., Davies, T.D., Portis, D., Gonzalez-Rouco, J.F., von Storch, H., Gyalistras, D., Casty, C., and Wanner, H., 2002a: Extending North Atlantic Oscillation Reconstructions Back to 1500. Atmos. Sci. Lett., 2, 114-124 (doi:10.1006/asle.2001.0044).
Luterbacher, J., Xoplaki, E., Dietrich, D., Rickli, R., Jacobeit, J., Beck, C., Gyalistras, D., Schmutz, C. and Wanner, H., 2002: Reconstruction of Sea Level Pressure fields over the Eastern North Atlantic and Europe back to 1500. Clim. Dyn., 18, 545-561.
Luterbacher, J. and E. Xoplaki, 2003: 500-year Winter Temperature and Precipitation Variability over the Mediterranean area and its Connection to the Large-scale Atmospheric Circulation. In Bolle, H.-J. (Ed): Mediterranean Climate - Variability and Trends. Springer Verlag, Berlin, Heidelberg, New York, pp. 133-153.
(available through: http://www.giub.unibe.ch/klimet/pub_climdyn.html#r2002)
Tayan� M, Karaca M, and Yenig�n O., 1997: Annual and seasonal air temperature trend patterns of climate change and urbanization effects in relation to air pollutants in Turkey. J. Geophys. Res. 102:1909-1919.
T�rkes M, S�mer UM, and Kili� G., 1995: Variations and trends in annual mean air temperatures in Turkey with respect to climatic variability. Int. J. Climatol. 15:557-569
T�rkes M, S�mer UM, and Kili� G., 1996: Observed changes in maximum and minimum temperatures in Turkey. Int. J. Climatol. 16:463-477
T�rkes M, S�mer UM, and Demir I. 2002: Re-evaluation of trends and changes in mean, maximum and minimum temperatures of Turkey, for the period 1929-1999. Int. J. Climatol. 22:947-977
T�rkes, M., 2003: Spatial and temporal variations in precipitation and aridity index series of Turkey. In Bolle, H.-J. (Ed): Mediterranean Climate - Variability and Trends. Springer Verlag, Berlin, Heidelberg, New York, pp. 181-213.
Xoplaki, E., Maheras, P. and Luterbacher, J., 2001: Variability of climate in meridional Balkans during the periods 1675-1715 and 1780-1830 and its impact on human life. Clim. Change, 48, 581-614.
(available through: http://www.giub.unibe.ch/klimet/pub_climdyn.html#r2002)
Xoplaki, E, 2002: Climate variability over the Mediterranean. PhD thesis University of Bern. 193 pages. Available through: http://sinus.unibe.ch/klimet/docs/phd_xoplaki.pdf
1. The major strength of this proposal is the broad extent of the tree ring data that will be generated and brought together with existing data to draw a conclusion on the solar effects on precipitation and temperature of many locations worldwide. The investigators have an ambitious plan for examining new and existing tree ring data in light of solar influence. The team is lead by an energetic and prolific established researcher who has gathered a team of co-researchers and collaborators that understand the complex nature of the research problem.
2. Another major strength of this proposal is that it could be an important piece of the solar/climate puzzle that is just beginning to be solved. The importance of this project in understanding the processes of climate change cannot be overstated.
1. A weakness of the proposed research effort is in the causal mechanism between the solar variations and its expression in the tree ring data. The THC has been indicated as a possible mechanism that will be investigated using two GCM's. I feel that the THC and the GCM could be too coarse of a mechanism to explain annual to decadal scale variations. My suggestion would be to focus more on sea surface temperatures and their effects on average jet stream position and intensity. As the tree ring data is from many different latitudes, the effect of expanding or shrinking climatic belts, westerlies, northeast trades, and tropics on a decadal scale could help explain differences in regional tree ring information.
Rapid Climate Change Research Grants Team
Science Programmes Directorate
Tel: 01793 411663
Fax: 01793 411655