Aspects of climate extremes in Finland Ari Venäläinen, Kirsti Jylhä, Andrea Vajda, Tiina Kilpeläinen, Seppo Saku…
Jan 03, 2016
Aspects of climate extremes in Finland
Ari Venäläinen, Kirsti Jylhä, Andrea Vajda, Tiina Kilpeläinen, Seppo Saku…
CLIMATE RISKS IN FINLAND
• storms low pressures, tornadoes, down bursts
• snow• slipperiness• icing• fox• turbulence• floods an drought• hot and cold spells• lightning
0
20
40
60
80
100
120
140
160
1801961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
Vuosi
Tu
uli
tap
au
ste
n l
uku
määrä
maa-a
sem
illa
Above 11 ms-1 wind cases on land areas (17 stations)
Number of storm days (>21 ms-1) at sea areas
Number of deep low pressures and rapid change of air pressure in Kajaani
Helsinki, Jokioinen, Sodankylä storms
0
50
100
150
200
250
1959 1963 1967 1971 1975 1979 1983 1987 1991 1995 1999 2003
Year
Dev
iati
on
fro
m m
ean
(%
)
980 hPa cases Above 20 hPa change
Above 9 hP gradient
How high wind speed we may experience?
TORNADOESKontiolahti 20.8.2004
Tornadoes in Finland
Tornadoes in different fujita classes
02468
10121416182022242628303234
X F0 F1 F2 F3 F4
F-SCALE
NU
MB
ER
OF
TO
RN
AD
OE
S
1796-1996 1997-2003
F2+
1796-1996: 45 %
1997-2003: 8 %
1(2)
Climatological characteristics of precipitation in Helsinki
20 50 500
Daily precipitation
Helsinki
0
50
100
150
200
10 100 1000
Return period (years)
Pre
cip
tati
on
(m
m/d
ay)
20 50 500
Return period of the duration (hour) of a rain event
Summer rain events in Helsinki in 1951-2000: duration and precipitation amount
Return period of precipitationamount (mm) in a rain event
Ref: Tiina Kilpeläinen
1, 2, 3, 6 and 12 month precipitation amounts in Finland
Monthly Two months Three months
Six months Twelve months
1- month2- months3- months6- months12- months
Snow damages
-40
-35
-30
-25
-20
-15
-10
-5
0
5
10
15
1.1
0.
1.1
1.
1.1
2.
1.1
.
1.2
.
1.3
.Date
Win
d s
pe
ed
(m
/s)
tem
ep
era
ture
(°C
)
0
5
10
15
20
25
30
35
40
45
Pre
cip
ita
tio
n (
mm
) a
cc
um
ula
ted
sn
ow
(
kg
/m2
)
wind tempaccum. prec
Kuusamo 1993-1994
Above 20 kg snow load on tree branches, days / 10 years
ACCLIM• part of Finnish adaptation research
• ”Climate extremes and estimated climate change based on the latest climate scenarios”
• In the first part of the study return periods of several parameters are calculated
Parameter StationHelsinki Turku Jokioinen Utti Jyväskylä Kauhava Joensuu Oulu Kuusamo Sodankylä Muonio Ivalo
TEMPERATUREMonthly mean X X X X X X X X X X X XDaily mean X X X X X X X X X X X XDaily maximum X X X X X X X X X X X XDaily minimum X X X X X X X X X X X XLength of hot spells (> 25 °C) X X X X X X X X X X X XLength of cold spells (< -20 °C) X X X X X X X X X X X XLength of cold spells (< -30 °C) X X X X X X X X X X X XDaily temperature range X X X
PRECIPITATIONMonthly X X X X X X X X X X X X14 days X X X X X X X X X X X X5 days X X X X X X X X X X X XDaily X X X X X X X X X X X X6 hours X XLength of dry spells X X X X X X X X X X X X (<10, <25, <50, <100 and <200 mm)
SNOWThe maximum snow depth X X X X X X X X
WIND Bågaskär Kallbodagrund Kuopio Hailuoto Lahti10 average X X X X Xgusts X X X X X
DRY SPELL (< 50 mm), summer
ret.per. 304 Helsinki Kaisaniemi 1101 Turku lentoasema1201 Jokioinen
observatorio1501 Utti lentokenttä
2401 Jyväskylä lentoasema
3201 Kauhava lentokenttä
(years) 95 % ka 95 % 95 % ka 95 % 95 % ka 95 % 95 % ka 95 % 95 % ka 95 % 95 % ka 95 %
10 82 90 102 70 82 92 68 74 85 65 74 84 62 67 75 73 78 87
20 90 100 120 75 90 109 74 82 99 69 82 101 67 74 86 79 86 99
50 98 110 148 80 100 137 81 92 120 74 91 123 74 82 104 87 93 117
100 103 117 164 84 106 148 86 98 130 77 97 134 78 88 114 91 98 129
500 111 127 183 90 116 166 96 111 152 84 108 155 87 101 135 98 107 143
Ret.per. 3801 Joensuu lentoasema 5401 Oulu lentoasema6801 Kuusamo
lentoasema7501 Sodankylä 8201 Muonio kk 9601 Inari
(years) 95 % ka 95 % 95 % ka 95 % 95 % ka 95 % 95 % ka 95 % 95 % ka 95 % 95 % ka 95 %
10 62 68 77 74 81 94 65 67 85 73 75 91 67 75 88 70 81 92
20 68 76 91 81 91 116 70 72 93 78 80 100 74 84 111 75 89 108
50 75 86 111 89 103 138 73 76 77 83 85 86 83 96 135 80 97 131
100 81 93 123 95 112 155 75 78 79 85 88 88 88 105 152 83 103 141
500 91 108 147 107 135 196 78 81 82 88 92 92 98 127 192 90 114 160
And the future?
December 2006 mean temperature in Helsinki was +4.0 ºC and March 2007 temperature +3.1ºC. The return periods of this high temperatures is more than 500 years
This two months demonstrate the difficulty to estimate the reliably the return periods in rapidly changing climate. How to explain all this to media and general public?