142
1. Luterbacher and E. Xop1aki
reduced. However, even without predictors from the Mediterranean there are
extended regions that can be partly meaningful reconstructed (Figure 4 bottom).
Areas with negative RE, therefore no skill in the reconstructions, are found over
parts of Africa, the centre of the Iberian Peninsula, Southern Italy, Central Turkey
and Syria. Therefore, one should be careful in interpreting these areas.
The driest reconstructed winter over the Mediterranean from AD 1500-1900 was
1609. The reconstructed precipitation field is given on top of Figure 4. The anomaly
fields indicate below normal precipitation generally south of around SOoN. The
largest negative precipitation anomalies can be found over Portugal, western Greece
and western Turkey. Higher then normal precipitation is visible mainly over Iceland,
the western part of the British Isles and Scandinavia. A striking feature is the above
normal precipitation values along the Northern African coast east of the prime
Meridian. The corresponding reconstruction quality clearly indicates the more
heterogeneous pattern compared to the temperature pattern. This is mainly due to
the fact that precipitation data reflect much greater variability, both in space and
time, compared to temperature. The majority of the grid points shows positive RE
values, thus there is an indication of potential to reconstruct precipitation from just
a few temperature and/or precipitation series (mainly from Switzerland, Germany,
Hungary, Southern Spain and Southern Jordan). Especially for the areas close to
these predictors, the quality is high but decreases fast further away from these
regions. Though some Mediterranean areas do provide skill in the precipitation
reconstruction for 1609, the general potential for trustworthy precipitation
reconstructions is rather small.
The wettest winter over the entire 496 years was 1684, within the Late Maunder
Minimum period. The reconstructed precipitation field and the departures from the
long-term 20 th century mean are given in Figure 4. It shows negative anomalies
north of around 48
c
N and wetter than normal conditions over the larger
Mediterranean area. Parts of the Mediterranean such as Portugal, Italy and the
western Balkans obtained 30 to 90 mm more rainfall than usual. However, there
were not everywhere wetter conditions over the Mediterranean region. The Northern
African coast east of lOoE for instance was even drier than usual. The quality of the
reconstruction (Figure 4 bottom) shows a similar pattern as for 1609. For 1684 there
were a few more predictors for the Mediterranean available, such as documentary
based reconstructed precipitation from Greece (Xoplaki et al. 2001 a), from different
places of Spain (Martin-Vide and Barriendos, 1995; Barriendos 1997) and Portugal
(Alcoforado et al. 2000). As for 1609, there is skill for some areas, though for the
majority trustworthy reconstructions is restricted.
1. Luterbacher and E. Xop1aki
reduced. However, even without predictors from the Mediterranean there are
extended regions that can be partly meaningful reconstructed (Figure 4 bottom).
Areas with negative RE, therefore no skill in the reconstructions, are found over
parts of Africa, the centre of the Iberian Peninsula, Southern Italy, Central Turkey
and Syria. Therefore, one should be careful in interpreting these areas.
The driest reconstructed winter over the Mediterranean from AD 1500-1900 was
1609. The reconstructed precipitation field is given on top of Figure 4. The anomaly
fields indicate below normal precipitation generally south of around SOoN. The
largest negative precipitation anomalies can be found over Portugal, western Greece
and western Turkey. Higher then normal precipitation is visible mainly over Iceland,
the western part of the British Isles and Scandinavia. A striking feature is the above
normal precipitation values along the Northern African coast east of the prime
Meridian. The corresponding reconstruction quality clearly indicates the more
heterogeneous pattern compared to the temperature pattern. This is mainly due to
the fact that precipitation data reflect much greater variability, both in space and
time, compared to temperature. The majority of the grid points shows positive RE
values, thus there is an indication of potential to reconstruct precipitation from just
a few temperature and/or precipitation series (mainly from Switzerland, Germany,
Hungary, Southern Spain and Southern Jordan). Especially for the areas close to
these predictors, the quality is high but decreases fast further away from these
regions. Though some Mediterranean areas do provide skill in the precipitation
reconstruction for 1609, the general potential for trustworthy precipitation
reconstructions is rather small.
The wettest winter over the entire 496 years was 1684, within the Late Maunder
Minimum period. The reconstructed precipitation field and the departures from the
long-term 20 th century mean are given in Figure 4. It shows negative anomalies
north of around 48
c
N and wetter than normal conditions over the larger
Mediterranean area. Parts of the Mediterranean such as Portugal, Italy and the
western Balkans obtained 30 to 90 mm more rainfall than usual. However, there
were not everywhere wetter conditions over the Mediterranean region. The Northern
African coast east of lOoE for instance was even drier than usual. The quality of the
reconstruction (Figure 4 bottom) shows a similar pattern as for 1609. For 1684 there
were a few more predictors for the Mediterranean available, such as documentary
based reconstructed precipitation from Greece (Xoplaki et al. 2001 a), from different
places of Spain (Martin-Vide and Barriendos, 1995; Barriendos 1997) and Portugal
(Alcoforado et al. 2000). As for 1609, there is skill for some areas, though for the
majority trustworthy reconstructions is restricted.