SOD-year Winter Temperature and Precipitation Variability over the Mediterranean Area
135
et al. 2001a, Grove 2001; Rodrigo et al. 2001; Mann 2001; D'Arrigo and Cullen
2001; Briffa et al. 2001 ab and many others). These climate reconstructions include
'multiproxy' networks consisting of diverse proxy indicators. They can be divided
in documentary proxy data and proxies derived from natural archives. The
documentary proxy evidence consists of chronicles and historiographies, narratives,
annals, records of public administration and government, scientific writings,
monastery records, etc. (Xoplaki et al. 200 I a) where meteorological indications such
as number of rainy days, direction of cloud movement, wind direction and related
events such as warm and cold spells, freezing of water bodies, droughts, floods,
advanced or delayed vegetation and other phenological and biological observations
can be found (Pfister et al. 1994; Martin-Vide and Barriendos 1995; Barriendos
1997; Glaser et al. 1999; Luterbacher et al., 2000; Alcoforado et al. 2000; Rodrigo
et al. 200 I; Xoplaki et al., 200 I a). The natural proxy cI imatic indicators are from
direct natural archives such as tree-ring data, corals, lake and marine warves and ice
cores which are all limited to specific regions. All these proxies contain direct or
indirect information about the course of meteorological phenomena or climate or
they describe natural phenomena and social events related to weather and climate
(Pfister et al. 1998; Xoplaki et al. 2001 a). Besides their obvious seasonal and spatial
limitations, different proxies are also potentially limited in their ability to represent
climatic variations over a range of different time scales (Jones et al. 1998).
To our knowledge, there are not yet continuous spatio-temporal high ly resolved
(monthly, seasonal) temperature and precipitation reconstructions for the whole
Mediterranean area for the last few centuries. New et al. (1999, 2000) published
gridded temperature and precipitation data of global land areas for the period 19011996 based on station data which were optimally interpolated on a very dense grid
with OS resolution. We extend this data set (OS longitude-latitude resolution) and
present seasonal gridded reconstructions oftemperature and precipitation over land
including the whole of Europe, the North African coast and the Near East region
back to AD 1500 by using early instrumental station series (pressure, temperature
and precipitation) combined with documentary proxy data. We first describe the
available data back to AD 1500 and present the statistical model to reconstruct
gridded temperature and precipitation fields back to AD.
We then define a time series of winter precipitation and temperature variations
by averaging the 2159 gridpoints in the larger Mediterranean region (30N-4TN
latitude and IOcW_40
C
E) and study its variability from AD 1500 to 1995.
From these long-term time series of temperature and precipitation we derive the
coldest, warmest, driest and wettest winters and plot the reconstructed temperature
and precipitation fields, show the departure from the 190 1-1995 long-term mean and
present the quality of these reconstructions. For these four anomalous winters the
corresponding large-scale reconstructed sea level pressure (SLP) distribution
(Luterbacher et al. 2001a), the departures from the long-term mean and the quality
of the reconstructions are given and discussed.
The temperature and precipitation time series for the larger Mediterranean area
are then correlated with recent independent North Atlantic Oscillation Index
135
et al. 2001a, Grove 2001; Rodrigo et al. 2001; Mann 2001; D'Arrigo and Cullen
2001; Briffa et al. 2001 ab and many others). These climate reconstructions include
'multiproxy' networks consisting of diverse proxy indicators. They can be divided
in documentary proxy data and proxies derived from natural archives. The
documentary proxy evidence consists of chronicles and historiographies, narratives,
annals, records of public administration and government, scientific writings,
monastery records, etc. (Xoplaki et al. 200 I a) where meteorological indications such
as number of rainy days, direction of cloud movement, wind direction and related
events such as warm and cold spells, freezing of water bodies, droughts, floods,
advanced or delayed vegetation and other phenological and biological observations
can be found (Pfister et al. 1994; Martin-Vide and Barriendos 1995; Barriendos
1997; Glaser et al. 1999; Luterbacher et al., 2000; Alcoforado et al. 2000; Rodrigo
et al. 200 I; Xoplaki et al., 200 I a). The natural proxy cI imatic indicators are from
direct natural archives such as tree-ring data, corals, lake and marine warves and ice
cores which are all limited to specific regions. All these proxies contain direct or
indirect information about the course of meteorological phenomena or climate or
they describe natural phenomena and social events related to weather and climate
(Pfister et al. 1998; Xoplaki et al. 2001 a). Besides their obvious seasonal and spatial
limitations, different proxies are also potentially limited in their ability to represent
climatic variations over a range of different time scales (Jones et al. 1998).
To our knowledge, there are not yet continuous spatio-temporal high ly resolved
(monthly, seasonal) temperature and precipitation reconstructions for the whole
Mediterranean area for the last few centuries. New et al. (1999, 2000) published
gridded temperature and precipitation data of global land areas for the period 19011996 based on station data which were optimally interpolated on a very dense grid
with OS resolution. We extend this data set (OS longitude-latitude resolution) and
present seasonal gridded reconstructions oftemperature and precipitation over land
including the whole of Europe, the North African coast and the Near East region
back to AD 1500 by using early instrumental station series (pressure, temperature
and precipitation) combined with documentary proxy data. We first describe the
available data back to AD 1500 and present the statistical model to reconstruct
gridded temperature and precipitation fields back to AD.
We then define a time series of winter precipitation and temperature variations
by averaging the 2159 gridpoints in the larger Mediterranean region (30N-4TN
latitude and IOcW_40
C
E) and study its variability from AD 1500 to 1995.
From these long-term time series of temperature and precipitation we derive the
coldest, warmest, driest and wettest winters and plot the reconstructed temperature
and precipitation fields, show the departure from the 190 1-1995 long-term mean and
present the quality of these reconstructions. For these four anomalous winters the
corresponding large-scale reconstructed sea level pressure (SLP) distribution
(Luterbacher et al. 2001a), the departures from the long-term mean and the quality
of the reconstructions are given and discussed.
The temperature and precipitation time series for the larger Mediterranean area
are then correlated with recent independent North Atlantic Oscillation Index