23.8.2007

TOLERATE research meeting

Progress by FMI: results & planned actions

Kirsti Jylhä

Thanks to material: Kimmo Ruosteenoja, Ari Venäläinen, Seppo Saku,Tiina Kilpeläinen, Teija Seitola

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)

Objective:

- 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

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:

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

Ref. Venäläinen et al. (2007)

Peaks-over-threshold (POT) method (Generalized Pareto distribution)using the eXtremes Toolkit (developed in NCAR)

Pre

cip

itat

ion

(m

m)

Return period (years) Return period (years)

Return period (years)Ref. Venäläinen et al. (2007)

max75th percentilemedian25th percentilemin

Return level estimates for precipitation amounts:rather large inter-stationdifferences

• random variability

• the relatively short periods of data (in digital form)

• spatial variation of climate

12 stations

Pre

cip

itat

ion

(m

m)

Pre

cip

itat

ion

(m

m)

RPCC

Return level estimates for duration of spells with only a small amount of precipitation*

max75th percentilemedian25th percentilemin

12 stations

Ref. Venäläinen et al. (2007)

*Total accumulated rain amountduring the time periodremains below a fixed threshold (10, 50, 100 or 200 mm)

RPCC

1971-2000 => 2020-2049Scenario Temperature rise (ºC)

A1FI 2.3 (1.2 – 3.3)

A2 2.0 (1.1 – 2.9)

A1B 2.1 (1.1 – 3.1)

A1T 2.5 (1.4 – 3.7)

B2 2.2 (1.2 – 3.2)

B1 1.9 (0.9 – 2.9)

Projected warming in Finland

Annual mean temperature

Cha

nge

in t

empe

ratu

re

(ºC

)Future climate FC

Ref: K. Ruosteenoja

Based on 19 GCMs, employed in the IPCC 4th Assessment Report

Multi-model means and 5-95% rangesof the model resultsbased on a Gaussian fit

0

10

20

30

2000 2050 2100

(Gt

C/v

uosi

)

Emission scenario

1971-2000 2020-2049 Scenario Response (%)

A1FI 8 (3 – 13)

A2 6 (2 – 11)

A1B 7 (2 – 12)

A1T 8 (3 – 14)

B2 7 (2 – 12)

B1 7 (2 – 11) Cha

nge

in p

reci

pita

tion

(%)

Annual mean precipitation amount

Projected increases in precipitation in Finland

Ref: K. Ruosteenoja

A measure of natural variability

Future climate FC

LEVEL OF UNCERTAINTY

Near future End of the century

Natural climate variability + +Models (+) ++Emission scenarios ++

• Larger changes in winter than in summer

• Little differences between the various emission scenarios

0

10

20

30

2000 2050 2100

(Gt

C/v

uosi

)

Emission scenario

Projected changes in monthly mean temperature (°C) in Finland by 2020-49*

*relative to 1971-2000

Cha

nge

in t

empe

ratu

re

(ºC

)

J F M A M J J A S O N D

1 vrk sademäärä

0

20

40

60

80

100

DMI_1 DMI_2 DMI_3 HC ETH SMHI KNMI

tois

tuvuusta

so [m

m]

10 v: 1961-1990

100 v:1961-1990

10 v: 2071-2100

100 v: 2071-2100

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)

Ret

urn

leve

l (m

m)

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)

Regional climate model experiments

Ret

urn

leve

l (m

m)

14 vrk sademäärä

0

20

40

60

80

100

120

140

160

DMI_1 DMI_2 DMI_3 HC ETH SMHI KNMI

tois

tuvu

ust

aso

[mm

]

10 v: 1961-1990

100 v:1961-1990

10 v: 2071-2100

100 v: 2071-2100

Ret

urn

leve

l (m

m)

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)

Regional climate model experiments

30 vrk sademäärä

0

50

100

150

200

250

300

350

DMI_1 DMI_2 DMI_3 HC ETH SMHI KNMI

tois

tuvu

ust

aso

[mm

]

10 v: 1961-1990

100 v:1961-1990

10 v: 2071-2100

100 v: 2071-2100

Ret

urn

leve

l (m

m)

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

- 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

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:

Work in progress: changes in precipitation amounts with return periods of 10 and 100 years