Transcript Slide 1

TOLERATE research meeting
Progress by FMI: results & planned actions
Kirsti Jylhä
Thanks to material:
Kimmo Ruosteenoja, Ari Venäläinen, Seppo Saku,
Tiina Kilpeläinen, Teija Seitola
23.8.2007
Objective:
The production of key climate indicators
- monthly average precipitation and temperatures
- extremes of various typical return periods
for
- recent past/current climate (RPCC)
- enhanced (future) climate (FC)
Deliverables from FMI to SYKE by August 2007
• A draft for the report by Venäläinen et al. (2007):
Sään ääri-ilmiöistä Suomessa. (Aspects about climate extremes in Finland)
Raportteja 2007: x, Ilmatieteen laitos. (about 75 pages, including Appendices)
• Two data files for changes in monthly mean temperature and precipitation:
- 2.5 ° x 2.5° grid covering Finland and the surroundings
- Both multi-model mean changes based on 19 global climate models
and projected changes separately from a subset of the models (7 GCMs)
- A2, A1B and B1 emission scenarios
- future periods 2020-49 and 2070-99, control period 1971-2000
Work in progress: changes in precipitation amounts with return
periods of 10 and 100 years
Recent past/current climate (RPCC)
• 12 weather stations in Finland
• Daily data from ~ 40 – 60 years
Peaks-over-threshold
(POT) method
(Generalized Pareto distribution)
using the eXtremes Toolkit
(developed in NCAR)
Ref. Venäläinen et al. (2007)
Return level estimates
for precipitation amounts:
rather large inter-station
differences
Return period (years)
• random variability
• the relatively short periods
of data (in digital form)
• spatial variation of climate
Ref. Venäläinen et al. (2007)
Return period (years)
Precipitation (mm)
max
75th percentile
median
25th percentile
min
Precipitation (mm)
12 stations
Precipitation (mm)
RPCC
Return period (years)
RPCC
Return level estimates for duration of spells
with only a small amount of precipitation*
12 stations
max
75th percentile
median
25th percentile
min
*Total accumulated rain amount
during the time period
remains below a fixed threshold
(10, 50, 100 or 200 mm)
Ref. Venäläinen et al. (2007)
Future climate FC
Projected warming in Finland
Change in temperature (ºC)
Annual mean temperature
1971-2000 => 2020-2049
Scenario Temperature rise (ºC)
Based on 19 GCMs,
employed in the IPCC
4th Assessment Report
(Gt C/vuosi)
Emission scenario
30
20
10
0
2000 2050 2100
A1FI
A2
A1B
A1T
B2
2.3 (1.2 – 3.3)
2.0 (1.1 – 2.9)
2.1 (1.1 – 3.1)
2.5 (1.4 – 3.7)
2.2 (1.2 – 3.2)
B1
1.9 (0.9 – 2.9)
Multi-model means
and 5-95% ranges
of the model results
based on a Gaussian fit
Ref: K. Ruosteenoja
Future climate FC
Projected increases in precipitation in Finland
Change in precipitation (%)
Annual mean precipitation amount
1971-2000
Scenario
2020-2049
Response (%)
A1FI
A2
A1B
A1T
B2
8 (3 – 13)
6 (2 – 11)
7 (2 – 12)
8 (3 – 14)
7 (2 – 12)
B1
7 (2 – 11)
A measure of natural variability
LEVEL OF
Near future End of the
UNCERTAINTY
century
Natural climate variability
+
+
Models
(+)
++
Emission scenarios
++
Ref: K. Ruosteenoja
Projected changes in monthly mean temperature (°C)
in Finland by 2020-49*
Change in temperature (ºC)
(Gt C/vuosi)
Emission scenario
30
20
10
0
2000 2050 2100
• Larger changes in winter
than in summer
• Little differences between
the various emission scenarios
J
F M A M J
J A
S O N D
*relative to 1971-2000
One-day precipitation amount (mm) with a return period of 10 and 100 years on
the basis observations and climate model simulations (an example, Turku)
1 vrk sademäärä
(mm)
level [mm]
Return
toistuvuustaso
100
80
60
10 v: 1961-1990
100 v:1961-1990
10 v: 2071-2100
40
100 v: 2071-2100
20
0
DMI_1
DMI_2
DMI_3
HC
ETH
SMHI
KNMI
Regional climate model experiments
Two-weeks precipitation amount (mm) with a return period of 10 and 100 years
on the basis observations and climate model simulations (an example, Turku)
14 vrk sademäärä
160
140
level (mm)
Return
toistuvuustaso
[mm]
Return level (mm)
120
100
10 v: 1961-1990
100 v:1961-1990
80
10 v: 2071-2100
60
100 v: 2071-2100
40
20
0
DMI_1
DMI_2
DMI_3
HC
ETH
SMHI
KNMI
Regional climate model experiments
One-month precipitation amount (mm) with a return period of 10 and 100 years
on the basis observations and climate model simulations (an example, Turku)
30 vrk sademäärä
350
(mm)
level[mm]
Return
toistuvuustaso
300
250
10 v: 1961-1990
200
100 v:1961-1990
10 v: 2071-2100
150
100 v: 2071-2100
100
50
0
DMI_1
DMI_2
DMI_3
HC
ETH
SMHI
KNMI
Regional climate model experiments
90th percentile of the monthly mean daily maximum temperature
in summers 1961-1990 in a regional climate model experiment driven by ERA40*
*ERA40= a global atmospheric analysis of conventional and satellite observations in 1957-2002
Projected changes (%) in heavy precipitation vs.
mean precipitation in winter and summer
5-95% ranges among the 19 AR4-GCMs
Deliverables from FMI to SYKE by August 2007
• A draft for the report by Venäläinen et al. (2007):
Sään ääri-ilmiöistä Suomessa. (Aspects about climate extremes in Finland)
Raportteja 2007: x, Ilmatieteen laitos. (about 75 pages, including Appendices)
• Two data files for changes in monthly mean temperature and precipitation:
- 2.5 ° x 2.5° grid covering Finland and the surroundings
- Both multi-model mean changes based on 19 global climate models
and projected changes separately from a subset of the models (7 GCMs)
- A2, A1B and B1 emission scenarios
- future periods 2020-49 and 2070-99, control period 1971-2000
Work in progress: changes in precipitation amounts with return
periods of 10 and 100 years