slcf and the arctic - unece

SLCF and the Arctic

Science update and preliminary results from recent modeling assessing black carbon effects on the Arctic

from different regions and different sources

Terje BerntsenUiO/CICERO

Geneva 13. September 2010

Activities under the AMAP expert group• Focus on Black Carbon aerosols• Modelling experiments to quantify impacts in terms of radiative

forcing from emissions in different regions and sectors• Batch A: 25 combinations of regions and sectors have been

identified

Status:• Two models have performed the simulations

– CESM (NCAR Earth system model) at Univ. of Michigan (Mark Flanner)– Oslo CTM2 at University of Oslo/CICERO (Karianne Ødemark and Terje

Berntsen)• Preliminary analysis of direct radiative forcing have been

performed• Analysis of radiative forcing due to deposition on snow and ice is

not yet available• A third model – GISS model (Koch/Unger) will do the simulations

Batch A

MM,OM,OM,OM,OGrass+forest

MM,OM,OM,OM,OIndustry/power/waste

MM,OM,OM,OM,OAgriculture

MM,OM,OM,OM,OTransport

MM,OM,OM,OM,ODomestic

ROWScandinaviaRussiaCanadaUSRegions/Sectors

Model: NCAR Community Earth System Model 1.0, resolution: 1.9 x 2.5 degrees

Configuration: Active atmosphere, land, sea-ice, and slab ocean model (active ocean/ice needed for sea-ice aerosol forcing). Initial conditions: Y2000 climate.

Aerosols: Bulk aerosol model (Rasch et al, 2001), no indirect cloud forcing in these runs

Sea-ice aerosol effect: Briegleb and Light (2007)

Snow aerosol effect: SNICAR (Flanner et al, 2007, 2009)

Model length: 14 month run (2 month spinup + one full year) for emissions from each region and sector

Emissions: Lamarque et al, ACP,2010

Instantaneous direct radiative forcing calculated within atmospheric, snow, and sea-ice components

Models/setup UiO/CICERO

• Oslo CTM2, offline global chemistry transport model,

• Resolution: T42 (2.8°x2.8°), 40 vertical layers be low 10 hPa

• Aerosols: Bulk scheme with modified aging times based on more detailed microphysical models (M7, Vignati et al., JGR)

• Radiative forcing: Derived from burden changes calculated by the Oslo CTM2 and normalized RF fields

nRF(BC_column, lat, long, month)

• Emissions: Lamarque et al, 2010

• BC in snow (land and sea ice). Simple snow-column budget module

Emissions of BC (Gg/yr) from sectors and regions

Emission Transport (Gg/yr)

0255075

100125150175200225250

US Canada Russia Scandinavia

Emission energy+industrial+waste (Gg/yr)

0255075

100125150175200225250


Emission domestic (Gg/yr)

0255075

100125150175200225250


Emission Grass+forest (Gg/yr)

0255075

100125150175200225250


Ranking of sources (regions and sectors) contribution to RF 60°-90°N

Univ. of Michigan

RF (direct) 60°-90°N (mWm-2)

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

18.0

dom

estic

(W)

gras

s+for

est (

R)

ener

gy+ind

ustria

l+waste

(W)

transp

ort (

W)

gras

s+for

est (

W)

gras

s+for

est (

C)

dom

estic

(R)

transp

ort (

US)

gras

s+for

est (

US)

ener

gy+ind

ustria

l+waste

(R)

transp

ort (

S)

transp

ort (

R)

agric

ultura

l (W

)

ener

gy+ind

ustria

l+waste

(US)

ener

gy+ind

ustria

l+waste

(S)

dom

estic

(US)

dom

estic

(S)

ener

gy+ind

ustria

l+waste

(C)

transp

ort (

C)

agric

ultura

l (R)

dom

estic

(C)

agric

ultura

l (US)

gras

s+for

est (

S)

agric

ultura

l (C)

agric

ultura

l (S)

Rad

iati

ve F

orc

ing

(m

Wm

-2)

Total RF 60-90 N: 79 mWm-2

C: Canada

S: Scandinavia

R: Russia

W: ROW

US: United States

RF (direct) 60°-90°N (mWm-2)

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

dom

estic

(R)

trans

port

(US)

ener

gy+ind

ustri

al+w

aste

(R)

trans

port

(S)

trans

port

(R)

ener

gy+ind

ustri

al+w

aste

(US)

ener

gy+ind

ustri

al+w

aste

(S)

dom

estic

(US)

dom

estic

(S)

ener

gy+ind

ustri

al+w

aste

(C)

trans

port

(C)

agric

ultur

al (R

)do

mes

tic (C

)

agric

ultur

al (U

S)ag

ricult

ural

(C)

agric

ultur

al (S

)

Rad

iative

For

cing

(m

Wm

-2)

RF (direct) 60-90N mWm-2

0

12

3

45

6

78

9

dom

estic

(R)

trans

port

(US)

ener

gy+i

ndus

trial

+waste

(R)

ener

gy+i

ndus

trial

+waste

(US)

trans

port

(R)

trans

port

(S)

dom

estic

(US)

ener

gy+i

ndus

trial

+waste

(S)

trans

port

(C)

ener

gy+i

ndus

trial

+waste

(C)

dom

estic

(S)

agric

ultu

ral (

R)do

mes

tic (C

)

agric

ultu

ral (

US)

agric

ultu

ral (

C)

gras

s+fo

rest

(S)

agric

ultu

ral (

S)

1

CESM (UM)

Oslo CTM2

Norm. RF (direct) 60°-90°N (mWm-2/Tg/yr)

0 25 50 75 100 125 150 175 200

grass+forest (S)

grass+forest (C)

grass+forest (R)

domestic (S)

energy+industrial+waste (S)

transport (S)

grass+forest (US)

agricultural (S)

domestic (R)

energy+industrial+waste (R)

transport (R)

agricultural (C)

agricultural (R)

energy+industrial+waste (C)

domestic (C)

transport (C)

agricultural (US)

transport (W)

energy+industrial+waste (US)

domestic (W)

energy+industrial+waste (W)

domestic (US)

transport (US)

agricultural (W)

grass+forest (W)

Norm. RF (direct) 60°-90°N

(mWm-2/Tg/yr)

0 50 100 150 200

grass+forest (S)

domestic (S)

transport (S)


grass+forest (C)

agricultural (S)

grass+forest (R)

grass+forest (US)

domestic (R)

transport (R)


agricultural (R)

agricultural (C)


domestic (C)

transport (C)

agricultural (US)


transport (US)

domestic (US)

RF (ice) 60°-90°N (mWm-2)

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50

grass+forest (S)


agricultural (US)

domestic (C)

transport (S)

energy+industrial+waste (W)


transport (R)

agricultural (W)

domestic (S)

agricultural (S)

grass+forest (R)


domestic (US)

domestic (W)

domestic (R)

transport (US)

agricultural (C)

grass+forest (W)


grass+forest (C)

transport (W)

grass+forest (US)

transport (C)

agricultural (R)

Why do the models differ?Emissions (equal)

Burden change Burden change

Radiative Forcing Radiative Forcing

• Burden Change:

- Atmospheric transport and mixing

- ”Aging” (Conversion from hydrophobic to hydrophilic form)- Deposition

• Radiative forcing

- Optical properties- Location of BC relative to clouds

- Surface albedo

Source region potential

Shindell et al., ACP, 2008

RF per unitburdenchange60-90 N

Norm. RF (direct) 60°-90°N (Wm-2/g/m2)

0 500 1000 1500 2000 2500 3000

domestic (US)


transport (US)

agricultural (US)

domestic (C)


transport (C)

agricultural (C)

domestic (R)


transport (R)

agricultural (R)

domestic (S)


transport (S)

agricultural (S)

grass+forest (S)

Norm. RF (direct) 60°-90°N

(Wm-2/gm-2)

0 500 1000 1500 2000 2500 3000

domestic (US)


transport (US)

agricultural (US)

grass+forest (US)

domestic (C)


transport (C)

agricultural (C)

grass+forest (C)

domestic (R)


transport (R)

agricultural (R)

grass+forest (R)

domestic (S)


transport (S)

agricultural (S)

grass+forest (S)

C: Canada

S: Scandinavia

R: Russia

W: ROW

US: United States

Change in BC burden 60-90N

∆BC Burden 60-90N mg/m2

0.0 2.0 4.0 6.0 8.0 10.0

grass+forest (R)

domestic (R)

transport (US)

grass+forest (C)


transport (R)


transport (S)

domestic (US)

grass+forest (US)


domestic (S)

transport (C)


agricultural (R)

domestic (C)

agricultural (US)

agricultural (C)

grass+forest (S)

agricultural (S)

∆BC Burden 60-90N (mg/m2)

0.0 2.0 4.0 6.0 8.0 10.0

grass+forest (R)

domestic (R)

grass+forest (W)

grass+forest (C)


transport (S)

transport (R)

grass+forest (US)


transport (US)

agricultural (W)

domestic (S)


domestic (US)

agricultural (R)


transport (C)

grass+forest (S)

domestic (C)

agricultural (US)

agricultural (S)

agricultural (C)

Does it matter where the forcing is located?

Shindell & Faluvegi, Nature Geoscience, 2009.

ResponseRegion: Arctic

Bond et al., in prep.

Preliminary conclusions• Most of ”Batch A” simulations have been carried out by twomodels – some diagnostics pending (most important RF due to BC on snow).

• Contribution to direct RF north of 60°N have been analy sed

• Ranking of sources largely robust between the models, abolutelevels appr. a factor of 2 different.

•Emissions from ”Rest of the World” and wildfires are most important for radiative forcing north of 60°N

• Apart from that, Domestic (Russia) and Transport (US) are themost important sources

• In terms of RF per unit of emissions, Scandinavian sources aremost effective

• Potentially important forcing mechanism and regional climatefeedbacks are NOT included in this analysis

Important factors towards identification of regions and sectors for cost-effective

mitigation of Black Carbon aerosols

• Absolute level of impact (here Radiative Forcing)• Impact normalized to emission (e.g. Wm-2/Tg(yr)-1)

Other factors not discussed here:• Changes in co-emitted species• Mitigation costs• Feasibility (Technologically and politically)

Ranking of sources (ROW and grass+forest removed) contribution to RF 60°-90°N.

Univ. of Oslo

RF (direct) 60-90N mWm-2

0

1

2

3

4

5

6

7

8

9

domes

tic (R

)

trans

port

(US)

ener

gy+in

dust

rial+w

aste

(R)

ener

gy+i

ndus

trial+

waste

(US)

trans

port

(R)

trans

port

(S)

dom

estic

(US)

ener

gy+in

dust

rial+w

aste

(S)

trans

port

(C)

ener

gy+i

ndus

trial+

waste

(C)

domes

tic (S

)

agric

ultur

al (R

)

domes

tic (C

)

agric

ultur

al (U

S)

agric

ultur

al (C

)

gras

s+fo

rest

(S)

agric

ultur

al (S

)

Other activities on understanding BC impacts on the climate

• ”Bounding BC” initiative (Bond, Fahey, Forster ++)

- Focus on quantifications (with uncertainties) of the effects of all possible processes where BC interacts with climate. Draft due soon.

• BC activity under EMEP/CLRTAP

- Focus country specific contribution to direct radiative forcing by BC aerosols

- Dedicated model simulations with the EMEP model at met.no(M. Gauss ++) with input on forcing efficiencies from CICERO (G. Myhre) � input to the GAINS model at IIASA

• UNEP assessment of BC

Historical Global BC Emissions (Tg/yr)

0.0

1.0

2.0

3.0

4.0

5.0

6.0

1850 1870 1890 1910 1930 1950 1970 1990 2010

Emissions in ”Rest of the World”Emission ROW (Gg/yr)

0

500

1000

1500

2000

2500

trans

port

gras

s+fo

rest

ener

gy+i

ndus

trial+

waste

dom

estic

agric

ultur

al

Climate impacts of soot aerosols in the Norwegian Earth System Model (NorESM)

Alf Kirkevåg, Trond Iversen,Jens Boldingh Debernard, Øyvind Seland, Mats Bentsen,

Corinna Hoose, Jón Egill Kristjánsson,Mark Flanner, Steve Ghan, Phil Rasch

IPY-Oslo Science conference,

Lillestrøm, June 10’th 2010

Acknowledgement:National Center for

Atmospheric Research, NCAR

Pacific Northwest National Laboratory,

PNNL

Light-absorption by soot and mineral dust on snow and sea-ice is included in NorESM

In the land model (CLM4 from NCAR):The SNow, ICe, and Aerosol Radiative (SNICAR) model

(Flanner et al., 2007; 2009)

• grain-size dep. snow aging

• aerosol deposition (BC, DU)

• meltwater scavenging of aerosol

• look-up tables for optical parameters

• multilayer radiative transfer in the snow

In the sea-ice model (CICE4 from NCAR): (Holland et al., 2010, draft in preparation)

• aerosol deposition (BC, DU)

• BC and DU impact on snow albedo through

CICE’s own radiation transfer module

Global near 2m temperature (K)

(JRA25 reanalysis 1979-2004)

Simulations - all fully coupled:

1. CTRL 68 years:Year 2000 aerosol emissions and GHG concentrations

2. noBCdep 68 years:As CTRL, but no effects of BC deposition on snow and sea-ice albedo

3. noBC 68 years: As CTRL, but BC aerosols excluded (entirely)

CTRLnoBCdepnoBC

years 39-68used in analysis

- 0.0011

- 0.00130.17

Response of all BC: CTRL – noBCTemp. albedo

Snow cover Sea-ice cover

- 0.0007

Reference: flow-regimesfrom re-analysed data

(Corti et al, 1999; Nature)

ClusterBPNA-; NAO+(NCEP Re-analysis)

NorESM:CTRL – noBC:Response to all BC

Response: NH winter mid-tropospheric flow (500hPa)

Emissions in all EU-27 countries

Emissions in all EMEP countries

RF (ice) 60°-90°N (mWm-2)

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50


agricultural (US)

domestic (C)

transport (S)


transport (R)

domestic (S)

agricultural (S)


domestic (US)

domestic (R)

transport (US)

agricultural (C)


transport (C)

agricultural (R)

Norm. RF (direct) 60°-90°N (mWm-2/Tg/yr)

0 20 40 60 80 100

domestic (S)


transport (S)

agricultural (S)

domestic (R)


transport (R)

agricultural (C)

agricultural (R)


domestic (C)

transport (C)

agricultural (US)


domestic (US)

transport (US)

slcf and the arctic - unece

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