European Alps Temperature and Precipitation Reconstructions
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               World Data Center for Paleoclimatology, Boulder
                                  and
                     NOAA Paleoclimatology Program
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NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!!


NAME OF DATA SET: European Alps Temperature and Precipitation Reconstructions
LAST UPDATE: 10/2005 (Original receipt by WDC Paleo)
CONTRIBUTORS: Carlo Casty, Heinz Wanner, Juerg Luterbacher, Jan Esper, Reinhard Boehm.
IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2005-070


SUGGESTED DATA CITATION:  Casty, C., et al.  2005. 
European Alps Temperature and Precipitation Reconstructions.
IGBP PAGES/World Data Center for Paleoclimatology 
Data Contribution Series # 2005-070.
NOAA/NCDC Paleoclimatology Program, Boulder CO, USA.


ORIGINAL REFERENCES: 
Casty, C., H. Wanner, J. Luterbacher, J. Esper, and R. Boehm. 2005.
Temperature and Precipitation Variability in the European Alps Since 1500.
International Journal of Climatology, Vol. 25, Issue 14, pp. 1855-1880 
(30 November 2005)  DOI: 10.1002/joc.1216.

Mitchell, T.D. and P.D. Jones. 2005. 
An improved method of constructing a database of monthly climate observations 
and associated high-resolution grids. 
International Journal of Climatology, 25, 693-712. 


ABSTRACT:
High-resolution temperature and precipitation variations and their seasonal 
extremes since 1500 are presented for the European Alps (43.25-48.25 °N and 
4.25-16.25 °E). The spatial resolution of the gridded reconstruction is given 
by 0.5° × 0.5° and monthly (seasonal) grids are reconstructed back to 1659 
(1500-1658). The reconstructions are based on a combination of long instrumental 
station data and documentary proxy evidence applying principal component 
regression analysis. Annual, winter and summer Alpine temperatures indicate 
a transition from cold conditions prior to 1900 to present day warmth. 
Very harsh winters occurred at the turn of the seventeenth century. 
Warm summers were recorded around 1550, during the second half of the 
eighteenth century and towards the end of the twentieth century. 
The years 1994, 2000, 2002, and particularly 2003 were the warmest since 1500. 
Unlike temperature, precipitation variation over the European Alps showed no 
significant low-frequency trend and increased uncertainty back to 1500. 
The years 1540, 1921 and 2003 were very likely the driest in the context of 
the last 500 years.  Running correlations between the North Atlantic Oscillation 
Index (NAOI) and the Alpine temperature and precipitation reconstructions 
demonstrate the importance of this mode in explaining Alpine winter climate 
over the last centuries. Winter NAOI correlates positively with Alpine temperatures 
and negatively with precipitation. These correlations, however, are temporally 
unstable. We conclude that the Alps are situated in a band of varying influence 
of the NAO, and that other atmospheric circulation modes controlled Alpine 
temperature and precipitation variability through the recent past.



GEOGRAPHIC REGION: European Alps (48.25-43.25 °N and 4.25-16.25 °E)
PERIOD OF RECORD:  1500 - 2000 AD

LIST OF FILES: readme_casty2005.txt (this file),
temp-mon.txt (Monthly Alpine temperature reconstruction 1659-2000),
temp-seas.txt (Seasonal Alpine temperature reconstruction 1500-1658),
precip-mon.txt (Monthly Alpine precipitation reconstruction 1659-2000),
precip-seas.txt (Seasonal Alpine precipitation reconstruction 1500-1658),
(space-delimited ASCII format).


DESCRIPTION:
The area is from 48.25-43.25N and 4.25E-16.25E on a 0.5 grid. 
The start point is at 48.25N and 4.25E the second at 48.25N and 4.75E and so on. 
Please see column names in the corresponding files. 
Missing values are marked as "NA".
The data 1900 onwards is the CRU TS2 reanalyis (Mitchell and Jones 2005).