Extreme precipitation over the Ukraine and global climate
change
Vyshkvarkova O., Voskresenskaya E.
Marine Hydrophysical Institute National Academy of Sciences of Ukraine
Sevastopol, Ukraine
The aim of presentation is to study the precipitation inequality, precipitation extremes and their trends over the Ukraine associated with climate change
Data: daily precipitation from Ukrainian hydrometeorological stations for period 1951 - 2005
Methods: 1) concentration index (CI); 2) climate indices
Ukraine topographic map
Precipitation inequality
Concentration index or Gini index (well known in economics)
characterizes the inequality of the share of precipitation intensity into the total amount
Definition of Concentration index (CI)
The line at 45 degrees represents perfect equality. The CI here can be thought of as the ratio of the area that lies between the line of equality and the Lorenz curve over the total area under the line of equality
Martin-Vide J., 2004
Annual CI distributions (1951 – 2005)
CI varies from 0.58 in Carpathian region to 0.64 in the Black Sea and Azov coastal region
minmax
Seasonal CI distributions0.54
The minimum CI value (0.54) is typical for the foothill of Carpathian Mountains in winter season and maximum CI value reached 0.71 in
spring in boundary region between steppe and marine zones
0.71
CI trends distributions in 1951-2005
Negative Positive
Linear trends are mainly negative in the all of seasons The highest values of negative CI trend are typical for the west region, especially in autumn. Positive CI trends are located in south-eastern
Ukraine
year winter spring
summer autumn
Pacific Decadal Oscillation (PDO)
Izmail
0,56
0,58
0,6
0,62
0,64
0,66
w inter spring summer autumn year
CI
PDO - PDO +
Kerch
0,48
0,5
0,52
0,54
0,56
0,58
0,6
0,62
0,64
0,66
w inter spring summer autumn year
CI
PDO - PDO +
Precipitation inequality in positive ( ) and negative phase ( )
Mantua N.J., et al., 1997
Climate shift 1976/1977
How does it work?
А+
А+А-
А-
А-А+
Voskresenskaya E.N., Maslova V.N., 2011
Scheme of storm tracks in positive and negative PDO phases
(PDO -)
0
0,1
0,2
0,3
0,4
С Л Б К Т Ч Л С В Ж Л Г
Час
тота
1948-1976 (ТДО-)
1977-2001 (ТДО+)
Cyc
lone
s fr
eque
ncy
1 2 3 4 5 6 7 8 9 10 11 12
(PDO+)
Vinnitsa
0,54
0,56
0,58
0,6
0,62
0,64
0,66
w inter spring summer autumn year
CI
PDO - PDO +
Kiev
0,54
0,56
0,58
0,6
0,62
0,64
w inter spring summer autumn year
CI
PDO - PDO +
Lvov
0,5
0,52
0,54
0,56
0,58
0,6
0,62
w inter spring summer autumn year
CI
PDO - PDO +
Askaniya Nova
0,52
0,54
0,56
0,58
0,6
0,62
0,64
0,66
w inter spring summer autumn year
CI
PDO - PDO +
Lugansk
0,54
0,56
0,58
0,6
0,62
w inter spring summer autumn year
CI
PDO - PDO +
Ukraine. Precipitation inequality
Climate indices
Precipitation extremes
Absolute thresholds:
The percentile threshold (95th percentile)
1960 1980 2000
0
10
20
30
40
50
60
70
80
90
100
Pre
cip
itat
ion
, mm
Kerch
R30mm
R20mm0
10
20
30
40
50
60
70
80
90
100
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29
Precipitation, mm
Fre
qu
ency
, %
Indices of extreme precipitation
R20mm R30mm
1960 1980 2000
0
1
2
3
4
num
be
r of
ca
ses
Sevastopolwinter, > 20 mm
1960 1980 2000
0
2
4
6
num
ber
of c
ases
Sevastopolsum m er, > 20 m m
1960 1980 2000
0
1
2
num
be
r o
f ca
ses
Sevastopol> 30 m m , sum m er
winter summer summer
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
negative positive
Trends of R20mm and R30mm
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
Precipitation 95th percentile
winter
The maximum values are in Crimea Mountains and the north-west coast of the Black Sea while minimum in north-west (forest zone).
Linear trend are predominantly negative
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
2 2 2 4 2 6 2 8 3 0 3 2 3 4 3 6 3 8 4 0 4 24 4
4 6
4 8
5 0
5 2
5 4
summerPrecipitation 95th percentile
Summer precipitation of 95th percentile is characterized by a homogeneous distribution with values about 23 – 24 mm.
Linear trends are predominantly positive
Conclusions• Precipitation inequality increases southward of
Ukraine from the north-west and the north-east. Annual and seasonal inequality linear trends are predominantly negative for the most part of the country.
• Precipitation inequality is more strong over the Ukraine in negative phase of Pacific Decadal Oscillation than in the positive phase.
• Linear trends of precipitation extremes are negative in winter and positive in summer on the most territory of Ukraine.
Thank you!