Climate change impacts and vulnerability in Europe 2016

Climate change impacts on environmental systems
high evapotranspiration. Meteorological droughts are
usually characterised using statistical indices, such as
the Standardised Precipitation Index (SPI), Standardised
Precipitation Evapotranspiration Index (SPEI) and
Reconnaissance Drought Index (RDI). A river flow
drought is characterised by unusually low river flow,
which may result from a prolonged meteorological
drought, possibly in combination with socio-economic
factors.
Past trends
Drought has been a recurrent feature of the European
climate. From 2006–2010, on average 15 % of the EU
territory and 17 % of the EU population have been
affected by meteorological droughts each year. In
the 1990s and 2000s the drought hotspots were
the Mediterranean area and the Carpathian Region
(Sepulcre-Canto et al., 2012; Spinoni et al., 2016).
The frequency of meteorological droughts in Europe
has increased since 1950 in parts of southern Europe
and central Europe (Austria and Hungary), but
droughts have become less frequent in northern
Europe and parts of eastern Europe (Map 4.9, left).
Trends in drought severity (based on a combination
of SPI, SPEI and RDI) also show significant increases
in the Mediterranean region (in particular the Iberian
Peninsula, France, Italy and Albania) and parts of
central and south-eastern Europe, and decreases
in northern and parts of eastern Europe (Map 4.9,
right) (Gudmundsson and Seneviratne, 2015; Spinoni,
Naumann, Vogt et al., 2015; Spinoni et al., 2016).
Most stream gauges in Europe show a decrease in
summer low flows over the second half of the 20th
century (Map 4.10). However, current data availability
is insufficient for attributing this trend to global climate
change (Stahl et al., 2010, 2012).
Map 4.9
Observed trends in frequency and severity of meteorological droughts
Drought frequency
0°
10°
60°
70°
Total drought severity
60°
70°
40°
40°
Observed trends in frequency and severity of meteorological droughts
Drought frequency
(events/decade)
+ 0.7
Outside coverage
Total drought severity
(score/decade)
+ 30
0 Significance of trends
0
– 0.7
0 500 1 000 1 500 km
– 30
Note:
This map shows the trends in drought frequency (number of events per decade; left) and severity (score per decade; right) of
meteorological droughts between 1950 and 2012. The severity score is the sum of absolute values of three different drought indices (SPI,
SPEI and RDI) accumulated over 12-month periods. Dots show trends significant at the 5 % level.
Source: Adapted from Spinoni, Naumann, Vogt et al., 2015.
Climate change, impacts and vulnerability in Europe 2016 | An indicator-based report
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