Air pollution and climate change Short lived climate forcers

Øystein Hov

Is it useful to control short-lived climate forcers?

UNEP and WMO 2011 – Integrated Assessment of Black Carbon and Tropospheric Ozone: Summary for Decision Makers.

Temperature evolution for the scenarios

Methane measuressuggested to be effective

Black Carbon Measuressuggested to be effective

Global benefits from full implementation of identified measures in 2050/2030 compared to reference scenario

UNEP and WMO 2011 – Integrated Assessment of Black Carbon and Tropospheric Ozone: Summary for Decision Makers.

Can we trust in these results?

• Emission scenario uncertainty?• Impact calculation uncertainty• Black Carbon forcing range assumed 0.3-0.6 Wm-2

(being on the high side of model results)• Estimated RF effect of the CH4 & BC measures

O3 0.18 / CH4 0.21 / BC 0.14 Wm-2 • Only two models used (GISS, ECHAM)

and simplified temperature response function

Meteorologisk Institutt met.no

Contributions from European countries to Arctic pollution

(2006)31%

12%

9%

9%6%

2%

18%

4%4%2% 3%

RU NO FI ATL SE GB PL FR NOS DE Rest

Secondary inorganic aerosols:

SO4, NO3, NH4

Primary PM25

8%5%

9%5%4% 2% 2%

4%

19%38%

4%

AMAP Assessment 2006: Acidifying pollutants, Arctic haze, and acidification in the Arctic www.amap.no

BC north of the Polar Circle 1991-2001 average

Impact on instantaneous forcing of 1 kt BCSource: EMEP/MSC-W, UniOslo, IIASA

EMEP domain0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35

ALAT

BASBYBE

BLSBABGHRCYCZDKEEFIFRMKDEGRHUISIEIT

KZLVLTLUMTMEMENL

NOSNOPLPT

MDRORURSSKSIESSECHTRUAUK

mWm2/kt BCNorthern Hemisphere

0.00 0.02 0.04 0.06 0.08 0.10ALAT

BASBYBE

BLSBABGHRCYCZDKEEFIFRMKDEGRHUISIEIT

KZLVLTLUMTMEMENL

NOSNOPLPT

MDRORURSSKSIESSECHTRUAUK

mW m2/kt BCArctic

0.00 0.05 0.10 0.15ALAT

BASBYBE

BLSBABGHRCYCZDKEEFIFRMKDEGRHUISIEIT

KZLVLTLUMTMEMENL

NOSNOPLPT

MDRORURSSKSIESSECHTRUAUK

mW m2/kt BC

Instantaneous forcing over

05/03/23

Surface temperature response to forcings by natural factors, anthropogenic GHGs and anthropogenic aerosols NorESM (→ GFCS via downscaling)

All forcings Anthropogenic GHGNatural (Solar + volcanoes)Anthropogenic Aerosols

global Arctic

S/N the fourth decade aheadHawkins and Sutton BAMS 2009

IPCC AR4 (2007) projected surface temperature changes 2090-2099 relative to 1980-1999 (multi-AOGCM average projection A1B SRES scenario)

Climate reanalysis and projections