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 and , control period 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)

Precipitation (mm) Return period (years) Ref. Venäläinen et al. (2007) max 75th percentile median 25th percentile min Return level estimates for precipitation amounts: rather large inter-station differences random variability the relatively short periods of data (in digital form) spatial variation of climate 12 stations Precipitation (mm) RPCC

Return level estimates for duration of spells with only a small amount of precipitation* max 75th percentile median 25th percentile min 12 stations Ref. Venäläinen et al. (2007) *Total accumulated rain amount during the time period remains below a fixed threshold (10, 50, 100 or 200 mm) RPCC

=> Scenario 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 Change in temperature (ºC) Future climate FC Ref: K. Ruosteenoja Based on 19 GCMs, employed in the IPCC 4th Assessment Report Multi-model means and 5-95% ranges of the model results based on a Gaussian fit (Gt C/vuosi) Emission scenario

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) Change in precipitation (%) 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 futureEnd of the century Natural climate variability++ Models(+)++ Emission scenarios++

Larger changes in winter than in summer Little differences between the various emission scenarios (Gt C/vuosi) Emission scenario Projected changes in monthly mean temperature (°C) in Finland by * *relative to Change in temperature (ºC) J F M A M J J A S O N D

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) Return level (mm) 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 Return level (mm)

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 Return level (mm)

90th percentile of the monthly mean daily maximum temperature in summers in a regional climate model experiment driven by ERA40* *ERA40= a global atmospheric analysis of conventional and satellite observations in

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 and , control period 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