Extreme summer Extreme summer temperatures in Greecetemperatures in Greece

Heat wavesHeat waves

PanagiotisPanagiotis GiannopoulosGiannopoulosHelllenicHelllenic National Meteorological ServiceNational Meteorological Service

The definition criterionfor a Heat Wave in Greece is:

at least

3 consecutive days with

max

air temperature >= 36.5oC

SUMMER 2007SUMMER 20073 strong and long duration 3 strong and long duration

heat wavesheat waves

I)I) 1919--28 June28 June

•• Eastern mainland and Eastern mainland and Aegean islands Aegean islands

•• Max. temp for Athens Max. temp for Athens 446.26.2oC

(110 year record)(110 year record)

•• Record for energy demandRecord for energy demand

II)18II)18--25 July25 July

•• North Greece (record North Greece (record ThessalonikiThessaloniki 44.044.0oC ) )

•• Athens Athens 45.045.0oC (the old record)(the old record)

•• NewNew record for energy demandrecord for energy demand

18 people died from heatstroke18 people died from heatstrokedue to Idue to I--II heat wavesII heat waves

III)21III)21--26 August26 August

•• West Greece West Greece •• big forest firesbig forest fires•• 70 deaths70 deaths

DataDataDaily Daily

Max temperatures Max temperatures from 19 stationsfrom 19 stationsdata 1975data 1975--20042004

•• (especially for (especially for Athens, Athens,

19551955--2007)2007)

In all stations is observed an increase over timeof the number of days

with temperature ≥ 36,5oC

This increase is smaller to the cities that are directly influenced from the sea

In many stations is observed an increase over time

of the number of days

with temperature ≥ 39,5oC

a higher frequency of heat waves is recordedover Ionian sea and across Mainland

AthensAthens

Number of days with T>36.5 Number of days with T>36.5 increaseincrease

Number of days with Τ>=36,5 οC

14,42

6,23 y = 0,2x - 424

y = -0,13x + 272

y = 0,08x - 147

0

5

10

15

20

25

30

35

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

year

#

Number of days T >39.5Number of days T >39.5 increaseincrease

Number of days T >39.5Number of days T >39.5 increaseincrease

Number of days with T>=39,5 oC

2,640,64

y = -0,03x + 69

y = 0,05x - 97

y = 0,06x - 122

0

2

4

6

8

10

12

1950 1960 1970 1980 1990 2000 2010

year

#

Number of heat waves incidentsNumber of heat waves incidentsincreaseincrease

Heat wave episodes per year

y = 0,03x - 67

0

1

2

3

4

5

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010

year

#

This increase cannot attributed only to This increase cannot attributed only to ““heat heat islandisland””

(for Athens the comparison between two stations (for Athens the comparison between two stations an urban and a rural an urban and a rural --semiurban showed no semiurban showed no significant difference)significant difference)

SourcesSourcesZIAKOPOULOS et all, 2008“HEAT WAVES IN HELLAS DURING THE SUMMER PERIOD AND HIGH TEMPERATURES RISK SCALING”

(9TH COMECAP2008)

PETROU 2007PETROU 2007HEAT WAVES IN HELLASHEAT WAVES IN HELLAS--SUMMER 2007SUMMER 2007

(WGCEF: 13rd Annual Meeting)

Thank youThank you