The Impact of Black Carbon on Arctic Climate - Atmospheric Chemistry

AMAP Technical Report No. 4 (2011)
<strong>The</strong> <strong>Impact</strong> <strong>of</strong> <strong>Black</strong> <strong>Carbon</strong> on
Arctic Climate
P.K. Quinn, A. Stohl, A. Arneth, T. Berntsen, J. F. Burkhart, J. Christensen,
M. Flanner, K. Kupiainen, H. Lihavainen, M. Shepherd, V. Shevchenko,
H. Skov, and V. Vestreng

Citation: AMAP, 2011. <strong>The</strong> <strong>Impact</strong> <strong>of</strong> <strong>Black</strong> <strong>Carbon</strong> on Arctic Climate (2011). By: P.K. Quinn, A. Stohl, A. Arneth,
T. Berntsen, J. F. Burkhart, J. Christensen, M. Flanner, K. Kupiainen, H. Lihavainen, M. Shepherd, V. Shevchenko,
H. Skov, and V. Vestreng. Arctic Monitoring and Assessment Programme (AMAP), Oslo. 72 pp.
ISBN – 978-82-7971-069-1
© Arctic Monitoring and Assessment Programme, 2011
Available as an electronic document from www.amap.no
Authors/AMAP Short-lived Climate Forcers Expert Group
P.K. Quinn 1 , A. Stohl 2 , A. Arneth 3 , T. Berntsen 4 , J. Burkhart 2 , J. Christensen 5 , M. Flanner 6 , K. Kupiainen 7,8 ,
H. Lihavainen 9 , M. Shepherd 10 , V. Shevchenko 11 , H. Skov 5 , and V. Vestreng 12
1
NOAA Pacific Marine Environmental Laboratory, Seattle, WA, USA
2
Norwegian Institute for Air Research, Kjeller, Norway
3
Lund University, Lund, Sweden
4
University <strong>of</strong> Oslo, Oslo, Norway
5
Aarhus University, Roskilde, Denmark
6
University <strong>of</strong> Michigan, Ann Arbor, Michigan, USA
7
Finnish Environment Institute, Helsinki, Finland
8
International Institute for Applied Systems Analysis, Vienna, Austria
9
Finnish Meteorological Institute, Helsinki, Finland
10
Environment Canada, Toronto, Canada
11
P.P. Shirshov Insitute <strong>of</strong> Oceanology <strong>of</strong> the Russian Academy <strong>of</strong> Sciences, Moscow, Russia
12
Norwegian Pollution Control Authorities, Oslo, Norway
AMAP Short-lived Climate Forcers Expert Group
Chairs: Patricia K. Quinn (USA), Andreas Stohl (Norway)
Scientific Secretary: John F Burkhart
Editing: Kristine Aasarød, Ann-Christine Engvall Stjernberg
Production: Carolyn Symon (carolyn.symon@btinternet.com), John Bellamy (johnbellamy@swipnet.se)
Printing: Narayana Press, Denmark (a swan-labelled printing company, 541 562)
Cover photo: Collecting the ‘Summit 99’ ice core at Summit, Greenland
Copyright holders and suppliers <strong>of</strong> photographic material reproduced in this volume are listed in context.
<strong>The</strong> Arctic Monitoring and Assessment Programme (AMAP) was established in June 1991 by the eight Arctic countries (Canada,
Denmark, Finland, Iceland, Norway, Russia, Sweden and the United States) to implement parts <strong>of</strong> the Arctic Environmental
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countries and organizations.
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including effects on health <strong>of</strong> Arctic human populations. <strong>The</strong>se are presented to Arctic Council Ministers in ‘State <strong>of</strong> the Arctic
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Contents
1. Introduction ....................................................................................................................................................................... 1
2. Formation and properties <strong>of</strong> black carbon ................................................................................................. 4
3. Measurement and modeling <strong>of</strong> black carbon concentrations ...................................................... 6
3.1. Overview <strong>of</strong> BC measurements ................................................................................................................................. 6
3.2. Atmospheric measurement <strong>of</strong> BC ............................................................................................................................ 8
3.2.1. Measurement <strong>of</strong> absorption ................................................................................................................................ 8
3.2.1.1. Filter-based absorption photometer ........................................................................................................... 8
3.2.1.2. Photoacoustic spectrometer ....................................................................................................................... 9
3.2.2. Measurement <strong>of</strong> BC mass ..................................................................................................................................... 9
3.2.2.1. Filter-based thermal-optical carbon analyzer .............................................................................................. 9
3.2.2.2. Single particle soot photometer ................................................................................................................ 10
3.3. Measurement <strong>of</strong> BC in snow ..................................................................................................................................... 10
3.3.1. Measurement <strong>of</strong> BC mass in snow .................................................................................................................... 10
3.3.2. Measurement <strong>of</strong> absorption due to BC in snow ............................................................................................. 10
3.4. Methods for modeling BC in the Arctic ................................................................................................................ 10
4. Emissions <strong>of</strong> black carbon and organic carbon in the Arctic context .................................... 11
4.1. Overview ......................................................................................................................................................................... 11
4.1.1. Emissions <strong>of</strong> BC and OC ...................................................................................................................................... 12
4.1.2. Anthropogenic emissions <strong>of</strong> BC and OC in 2000 ............................................................................................ 13
4.1.3. BC and OC emissions in the Arctic Council nations ........................................................................................ 16
4.1.4. Arctic shipping ...................................................................................................................................................... 18
4.1.5. Emissions in the AMAP area ............................................................................................................................... 20
4.1.6. Forest and grassland fires (natural and semi-natural fires) ........................................................................... 23
4.1.7. BC emission inventory uncertainties ................................................................................................................ 26
4.2. Future emissions scenarios ....................................................................................................................................... 27
4.3. BC and OC emissions scenarios outside the Arctic Council nations .......................................................... 28
4.4. Emissions <strong>of</strong> co-emitted species ............................................................................................................................. 28
5. Transport <strong>of</strong> black carbon to the Arctic ........................................................................................................ 29
5.1. Conceptual overview .................................................................................................................................................. 29
5.2. BC source regions ......................................................................................................................................................... 32
6. <strong>Black</strong> carbon distribution, seasonality, and trends .............................................................................. 39
6.1. Distribution <strong>of</strong> BC ......................................................................................................................................................... 39
6.1.1. Atmosphere ........................................................................................................................................................... 39
6.1.2. Snow ....................................................................................................................................................................... 41
6.2. Seasonality in atmospheric BC concentrations ................................................................................................. 42
6.3. Trends ............................................................................................................................................................................... 44
6.3.1. Historical trends ................................................................................................................................................... 44
6.3.2. Measured trends ................................................................................................................................................... 44
i

7. Mechanisms <strong>of</strong> Arctic climate forcing by black carbon ................................................................... 45
7.1. Atmospheric forcing ................................................................................................................................................... 45
7.2. Indirect and semi-direct atmospheric forcing ................................................................................................... 48
7.3. Snow and ice forcing .................................................................................................................................................. 48
7.4. Dynamical influence on response to forcing ..................................................................................................... 49
7.5. Summary ......................................................................................................................................................................... 49
8. Linking sources to Arctic radiative forcing ................................................................................................ 50
8.1. Introduction to modeling studies conducted for this report ....................................................................... 50
8.2. Emissions used .............................................................................................................................................................. 51
8.3. Model description ........................................................................................................................................................ 52
8.4. Model results ................................................................................................................................................................. 52
8.4.1. Contribution to change in BC burden .............................................................................................................. 52
8.4.2. Contribution to RF in the Arctic ......................................................................................................................... 53
8.4.3. RF per unit emission ............................................................................................................................................ 56
8.4.4. RF by latitude <strong>of</strong> emissions ................................................................................................................................. 57
8.4.5. RF due to projected increases in global and Arctic shipping ...................................................................... 57
8.4.6. Relation between RF and temperature change .............................................................................................. 58
9. Summary findings on impacts <strong>of</strong> black carbon on Arctic climate and
relevance to mitigation actions ........................................................................................................................ 60
10. Information and science needs ....................................................................................................................... 61
10.1. Recommendations for improved characterization <strong>of</strong> spatial and vertical distribution <strong>of</strong>
BC and OC in the Arctic environment and deposition processes ............................................................ 61
10.2. Recommendations for emissions information ................................................................................................ 62
10.3. Recommendations for model development, evaluation and application ............................................ 62
References .............................................................................................................................................................................. 63
Abbreviations ....................................................................................................................................................................... 70
ii

1. Introduction
Sea Ice Extent-September 2010
Total extent = 4.9 million sq km
median ice edge
1

2

Winter Spring Summer
Longwave indirect
effect
Thin clouds
aerosol
BC snow albedo
effect
Less reflection from
darkened snow and
ice surfaces
aerosol
Aerosol indirect effect
Stronger reflection:
aerosols enhance
cloud albedo
aerosol
Aerosol direct effect
Biomass buming
or other pollution layers
lead to shortwave
absorbtion: ∆T A > 0
Enhanced
Cloud
Longwave
Emissivity
∆T s > 0
∆T s > 0
Less radiation
reaches the surface
and leads to cooling,
but net effect over
bright surfaces is small
because little radiation
is absorbed anyway
Net effect at surface can
be positive or negative,
depending on aerosol type
and surface albedo
Enhanced
longwave
∆T s > 0
Reduced
shortwave
BC deposit
∆T s ≈ 0
∆T s ≈ 0
Earlier melting
∆T s < 0
∆T s < 0
3

Non-Arctic
(Section 4)
Emissions
Arctic
Anthropogenic
Forest / grass wildfires
(Section 5)
Transport
(Section 6)
Atmospheric
Composition
Response
Atmospheric loading
(total column)
Surface concentrations
Surface deposition
(Section 8)
Arctic regional
response within the
global system
Radiative Forcing
Albedo <strong>Impact</strong>s
Cloud <strong>Impact</strong>s
Climate
Response
Temperature
Precipitation
Snow / Ice cover
and extent
(Section 3)
(Section 7)
Feedbacks
2. Formation and properties
<strong>of</strong> black carbon
4

5

Evolution <strong>of</strong> BC particles in the Arctic
<strong>Black</strong> carbon particles undergo transformation as they are
transported to the Arctic. Initially emitted as hydrophobic, they
are resistant to removal from the atmosphere through wet
deposition so that they are able to enter the free troposphere.
During transport, they grow through coagulation with other
particles and condensation <strong>of</strong> gas phase species.
1 2
Transport
During transport, on a timescale <strong>of</strong> tens <strong>of</strong>
hours, aggregates form external mixtures
(1), which are hydrophilic. <strong>The</strong>se eventually,
after chemical mixing, form a mixture <strong>of</strong>
coated and internally mixed particles (2).
<strong>The</strong> radiative impact <strong>of</strong> these particles is
highly dependent on mixing state.
Emissions
During combustion
hundreds <strong>of</strong>
particles form
aggregates or chain
like structures.
Soot particle
An individual soot
particle <strong>of</strong> organized
graphitic layers has a
typical diameter <strong>of</strong>
~100 nm and is
hydrophobic.
3. Measurement and
modeling <strong>of</strong> black carbon
concentrations
3.1. Overview <strong>of</strong> BC measurements
6

7

3.2. Atmospheric measurement <strong>of</strong> BC
3.2.1. Measurement <strong>of</strong> absorption
3.2.1.1. Filter-based absorption photometer
2009
2009
Canada
Canada
2008
2008
Switchyard
Barrow
Switchyard
U.
Barrow
Victoria
Greenland
U. Victoria
Tromso
Greenland
Russia
Tromso
Russia
2007
2007
North Pole
Greenland
North Pole
Greenland
Greenland
AWS
Svalbard
Greenland AWS
Russia
Svalbard
Canada
Russia
APLIS
Canada
Svalbard
APLIS
NPI
McCail
Svalbard
Glacier
NPI
McCail Glacier
1983-2006
1983-2006
Clarke and Noone
1983-1984 Clarke and Noone
1983-1984
SHEBA 1998
HOTRAX
SHEBA 1998
2005
Greenland
HOTRAX 2005
2006
Greenland 2006
8

3.2.1.2. Photoacoustic spectrometer
3.2.2. Measurement <strong>of</strong> BC mass
3.2.2.1. Filter-based thermal-optical carbon
analyzer
9

3.2.2.2. Single particle soot photometer
3.3. Measurement <strong>of</strong> BC in snow
3.3.1. Measurement <strong>of</strong> BC mass in snow
3.3.2. Measurement <strong>of</strong> absorption due to
BC in snow
3.4. Methods for modeling BC in the
Arctic
10

4. Emissions <strong>of</strong> black carbon
and organic carbon in the
Arctic context
4.1. Overview
11

4.1.1. Emissions <strong>of</strong> BC and OC
12

4.1.2. Anthropogenic emissions <strong>of</strong> BC and
OC in 2000
Tg/1.9 degrees latitude
0.40
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0
-90.0
-82.4
Tg/1.9 degrees latitude
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0
-90.00
-82.42
Shipping
Agricultural burning
-74.8
-67.3
-59.7
-52.1
-44.5
-36.9
-29.4
-21.8
-74.84
-67.26
-59.68
-52.11
-44.53
-36.95
-29.37
-21.79
-14.2
-6.6
0.98.5
Latitude
-14.21
-6.63
Latitude
Domestic
Transport
0.95
8.53
BC
16.1
23.7
31.3
38.8
46.454.0
61.6
69.2
76.7
84.3
16.11
23.68
31.26
38.84
46.42
54.00
Energy and industrial
production, waste
OC
61.58
69.16
76.74
84.32
13

BC
Land transport
OC
Land transport
BC
Domestic combustion
OC
Domestic combustion
BC
Agricultural waste burning
OC
Agricultural waste burning
mol/cm 2 /s
0.0 4.0E+08 8.0E+08 1.2E+09 1.6E+09 2.0E+09
(data min = 0.0, max = 3.49E+09)
14

Canada*
Nordic
3%
countries*
3%
Ukraine
5%
United States
<strong>of</strong> America*
13%
China
15%
Others
8%
Russia*
16%
EU-27
(excluding
the Arctic
Council
member
countries)
37%
15

North America Europe, European Russia Central and NE Asia, Asian Russia
Fire counts
Fire counts
Fire counts
1600
2002
50000
20000
1400
2003
1200
40000
15000
2001
1000
30000
800
10000
600
20000
400
5000
10000
200
0
0
0
J F M A M J J A S O N D J F M A M J J A S O N D J F M A M J J A S O N D
4.1.3. BC and OC emissions in the Arctic
Council nations
Emissions, Gg/y
12000
10000
8000
6000
4000
2000
0
Global
Emissions, Gg/y
1200
1000
800
600
400
200
Arctic nations
0
BC OC BC OC
Rest <strong>of</strong> world Arctic nations United States Russia
Nordic countries Canada
16

BC emissions, Gg/y
60
Canada
OC emissions, Gg/y
120
Canada
50
100
40
80
30
60
20
40
10
20
0
Bond
AMAP emissions
inputs
GAINS
0
Bond
AMAP emissions
inputs
GAINS
BC emissions, Gg/y
40
35
30
25
20
15
10
5
0
Bond
AMAP emissions
inputs
Nordic countries
GAINS
OC emissions, Gg/y
70
60
50
40
30
20
10
0
Bond
AMAP emissions
inputs
Nordic countries
GAINS
Russia
Russia
BC emissions, Gg/y
250
200
150
OC emissions, Gg/y
700
600
500
400
100
50
300
200
100
0
Bond
AMAP emissions
inputs
GAINS
0
Bond
AMAP emissions
inputs
GAINS
BC emissions, Gg/y
450
400
350
300
250
200
150
100
50
0
Bond
AMAP emissions
inputs
United States
GAINS
OC emissions, Gg/y
600
500
400
300
200
100
0
Bond
AMAP emissions
inputs
United States
GAINS
Other Flaring Agricultural Energy and industrial production, waste Transport Domestic
17

4.1.4. Arctic shipping
18

2004 BC emissions
2030 BC emissions - no control
2030 BC emissions - MFR control
BC emissions, g/5km grid cell
2 to 535
536 to 1267
1268 to 3209
3210 to 8981
8982 to 997,817
19

4.1.5. Emissions in the AMAP area
80° N
70° N
60° N
Boundaries <strong>of</strong> the Arctic
Arctic Circle
AMAP area
20

BC and OC emissions, Mg
4000
3500
3000
2500
2000
1500
1000
500
0
Electricity and
Heat Generation
Industry
Residential (3/4 wood, 1/4 coal)
Road Transport: Diesel
Road Transport: Gasoline
Off-road: Aviation
BC
Off-road: Marine
OC
Off-road: Gasoline
Off-road: Diesel
Open sources/burning
BC and OC emissions, Mg
250
200
150
100
50
0
Electricity and
Heat Generation
Industry
Residential ( wood)
Commercial and Institutional
BC
OC
Road Transport: Diesel
Road Transport: Gasoline
Off-road: Aviation, Rail
Off-road: Marine
Off-road: Gasoline, LPG, CNG
Off-road: Diesel
Open sources/burning
21

BC emissions, Mg
25
20
15
10
5
0
Public power
Combustion-industry
1990
Civil Aviation
Road
2000
2010
Navigation
Institutional plants
Domestic heating
Fishery (mobile)
Military (mobile)
Daily cruises
Goods transport
Barentsburg
Coal transportation
Barentsburg
2007
2006
2005
2004
2003
2002
2001
2000
Administration and
surveillance
Goods transport LYR
Research Vessels
Expeditions
Coal transportation Svea
International cruises
0 5 10 15 20 25
BC emissions, Mg
22

4.1.6. Forest and grassland fires (natural
and semi-natural fires)
23

24

Global
BC emissions, Gg/y
3000
2500
Arctic nations
BC emissions, Gg/y
600
500
Global
OC emissions, Gg/y
30000
25000
Arctic nations
OC emissions, Gg/y
6000
5000
2000
400
20000
4000
1500
300
15000
3000
1000
200
10000
2000
500
100
5000
1000
0
0
0
0
Rest <strong>of</strong> world Arctic nations United States Russia Nordic countries Canada
Latitude
90
60
30
0
-30
-60
-90
90
60
30
0
-30
-60
-90
1999-12
2000-01
2000-02
2000-03
2000-04
2000-05
2000-06
2000-07
kg/m 2 /s
2000-08
2000-09
2000-10
2000-11
0.0 1.0E+09 2.0E+09 3.0E+09 4.0E+09 5.0E+09
(data min = 0.0, max = 1.39E+10)
2000-12
25

4.1.7. BC emission inventory uncertainties
Fossil fuel
BC emissions, Gg/y
500
400
300
Low
Central
High
BC emissions, Gg/y
250
200
150
30° to 60° N
Asia
200
100
Europe
100
50
North America
0
-90 -45 0
45 90
Latitude
0
-180 -90 0
90 180
Longitude
BC emissions, Gg/y
600
500
400
300
200
100
Low
Central
High
0
-90 -45 0
45 90
Latitude
Biomass and bi<strong>of</strong>uel
BC emissions, Gg/y
80
70
30° to 60° N
60
50
Asia
40
30
North America
Europe
20
10
0
--180 -90 0
90 180
Longitude
26

4.2. Future emissions scenarios
BC emissions, Gg/y
700
600
500
400
300
200
100
0
2000 2005
OC emissions, Gg/y
900
800
700
600
500
400
300
200
100
0
2000 2005
Other
Flaring
Agricultural
Energy and industrial production, waste
CLE CLE Low
GAINS GAINS GAINS
2020 2030 2030
CLE CLE Low
GAINS GAINS GAINS
2020 2030 2030
Transport
Domestic
27

4.3. BC and OC emissions scenarios
outside the Arctic Council nations
BC emissions, Gg/y
6000
5000
4000
3000
2000
1000
0
OC emissions, Gg/y
14000
12000
10000
8000
6000
4000
2000
0
GAINS
2000
GAINS
2000
Other
AMAP
emission
inputs
2000
AMAP
emission
inputs
2000
Flaring
Agricultural
Energy and industrial production, waste
CLE
GAINS
2020
CLE
GAINS
2020
CLE
GAINS
CLE
GAINS
2030
Low
GAINS
2030 2030
Transport
Low
GAINS
2030
Domestic
4.4. Emissions <strong>of</strong> co-emitted species
28

CH4 ÷ 10
CO ÷ 10
NO X
SO 2
OC x 10
BC x 10
CLE GAINS 2030
Low GAINS 2030
2005
0 10000 20000 30000
Emissions, Gg/y
5. Transport <strong>of</strong> black carbon
to the Arctic
5.1. Conceptual overview
29

8. Pyro-Cb:
Injection into
stratosphere
6. Fast transport
in free troposphere
with multiple aerosol
removal events
4. Slow descent into polar dome
5. Slow mixing into polar dome
Tropopause
9. Top <strong>of</strong> Greenland
does not receive
low-level transport
Polar Dome
1. Lifting at Arctic front,
BC deposition on snow
Arctic sources
pollute directly
3. Low-level transport
North America
Greenland
7. Agricultural fires
can emit aerosols into
free troposphere with
little removal
Eurasia
2. Lifting at low
latitudes
removes most
aerosols outside
the Arctic
30

Zeppelin Alert Barrow Summit
Winter
Summer
0.0001 0.0005 0.0007 0.001 0.005 0.0075 0.01 0.05 0.075 0.1
S T , ns * m 3 /kg
31

5.2. BC source regions
a
b
BB enhancement/background burden, % BB enhancement/background burden, %
300
300
250
April 2008 250
April 2003-2007
200
150
Gas phase
Aerosol
200
150
100
100
50
50
0
CO
Acetonitrile
Benzene
Methanol
Propane
Acetone
N-pentane
Aerosol sulfate
Aerosol mass
Aerosol organics
BC
0
CO
Acetonitrile
Benzene
Methanol
Propane
Acetone
N-pentane
Aerosol sulfate
Aerosol mass
Aerosol organics
BC
32

33

Dec-Feb Mar-May Jun-Aug Sep-Nov
R 90
0 0.05 0.1 0.15 0.2 0.25
R 10
EBC concentration, ng/m 3
Alert
100
50
0
60
40
20
0
Barrow
60
Zeppelin
40
20
0
1984 1989 1994 1999 2004 2009
Arctic Ocean North America North Pacific Ocean and Southeast Asia Northern Eurasia Western Northern Eurasia Eastern Northern Eurasia
34

Pressure, hPa
Pressure, hPa
50
100
Spring ARCTAS
NASA DC-8
April
50
100
Spring ARCTAS
NASA P3-B
April
200
200
500
500
1000
1000
50
100
ARCPAC
NOAA WP-3D
April
50
100
Summer ARCTAS
NASA DC-8
June-July
200
200
500
500
1000
50
100
200
500
Summer ARCTAS
NASA P3B
June-July
1000
0.5 1 2 5 10 20 50 100 200 500
BC concentration, ng/kg
80°N
60°N
40°N
180°E 120°E 60°E 0°E
Campaigns
Spring ARCTAS
Spring ARCTAS
Spring ARCPAC
Summer ARCTAS
Summer ARCTAS
1000
0.5 1 2 5 10 20 50 100 200 500
BC concentration, ng/kg
Models
ARQM
SPRINTARS
MOZART
UIO GCM (dash)
GOCART
TM5 (dash)
CAM
LOA
MPI
ULAQ (dash)
MATCH
GISS
LSCE
MIRAGE
UMI (dash)
UIO CTM
DLR (dash)
35

BC concentration, ng/kg
1000
Alert
Observation
100
Improved
10
BC surface concentration, ng/m 3
200 Alert (1989-2005)
150
100
Observations
Original run
Dry deposition run
In-cloud run
Enhanced run
1.0
Original
50
0.1
0
1000
Barrow
120
Barrow (1988-2007)
100
90
10
60
1.0
30
0.1
0
1000
Zeppelin
120
Zeppelin (1998-2008)
100
90
10
60
1.0
30
0.1
FJA M M J J A S O N D
0
FJA M M J J A S O N D
36

BC concentration, ng/m 3
BC concentration, ng/m 3
80
Measured values
Nord
80
Alert
60
DEHM calculated values
60
40
40
20
20
0
0
80
Zeppelin
80
Barrow
60
60
40
40
20
20
0
0
1/08 7/08
1/09
7/09
80
Summit
60
40
20
0
1/08 7/08
1/09
7/09
37

Measured BC
concentration, ng/m 3
80
60
Measured values
Modelled BC
concentration, ng/m 3
20
Nord
15
EBC concentration, ng/m 3
80
60
Modelled BC
concentration, ng/m 3
20
Alert
15
40
OSLO CTM2
calculated values
10
40
10
20
0
Measured BC concentration, ng/m 3
80
NCAR CCSM
calculated values
Zeppelin
5
0
20
20
0
EBC concentration, ng/m 3
80
Barrow
5
0
20
60
15
60
15
40
10
40
10
20
5
20
5
0
EBC concentration, ng/m 3
80
Summit
0
20
0
1/08 5/08 9/08 1/09 5/09 9/09
0
60
15
40
20
0
1/08 5/08 9/08 1/09 5/09 9/09
10
5
0
38

6. <strong>Black</strong> carbon distribution,
seasonality, and trends
6.1. Distribution <strong>of</strong> BC
6.1.1. Atmosphere
39

Altitude, km
12
10
8
ARCTAS DC-8 (North Alska April)
Improved
Observation
Original
Altitude, km
10
8
ARCTAS DC-8 (Arctic NA April)
6
6
4
4
2
2
0
0.01 1
0
0.01 0.1 1
10 100 1000
12
10
8
0.1 10 100 1000
0
ARCTAS DC-8 (Arctic NA July)
12
10
8
ARCTAS DC-8 (South Canada July)
6
6
4
4
2
2
0
0.01 0.1 1
10 100 1000
0
0.01 0.1 1
10 100 1000
8
ARCTAS P-3B (Alaska April)
8
ARCTAS P-3B (Canada July)
6
6
4
4
2
2
0
0.01 0.1 1
10 100 1000
BC concentration, ng/kg
0.01 0.1 1
10 100 1000
BC concentration, ng/kg
40

Altitude, km
8
6
4
2
0
Arctic, 12 April 2008
Arctic, 15-21 April 2008
Midlatitudes, 11 September - 12 October 2006
1 10 100 1000
BC mass mixing ratio, ng/kg
Altitude, km
10
9
8
7
6
5
4
3
2
1
15 March
11 March
0
0 200 400 600 800 1000 1200 1400
BC concentration, ng/m 3
6.1.2. Snow
41

6.2. Seasonality in atmospheric BC
concentrations
42

EBC concentration, ng/m 3
10 4
10 3
10 2
10 1
10 0
10 4
Barrow
10 3
10 2
10 1
Alert
EBC concentration, ng/m 3
120
100
Alert
80
60
Barrow
40
20
0
Jan Mar May Jul Sep Nov Jan
10 0
43

6.3. Trends
6.3.1. Historical trends
Global BC emissions, Tg/y
6
5
4
3
2
1
0
1850 1900 1950 2000
6.3.2. Measured trends
BC emissions, kg x 10 -5 /m 2 /y
8
7
6
5
4
3
2
1
1750
1850
1900
1910
1920
1930
1940
1950
1960
1970
1980
1990
2000
Fossil fuel and bi<strong>of</strong>uel
0
90° S 60° S 30° S 0 30° N 60° N 90° N
BC emissions, kg x 10 -5 /m 2 /y
3
Biomass burning
2.5
2
1.5
1
0.5
0
90° S 60° S 30° S 0 30° N 60° N 90° N
44

7. Mechanisms <strong>of</strong> Arctic
climate forcing by black
carbon
7.1. Atmospheric forcing
45

46

Arctic BC burden, Gg
9
8
7
6
5
4
3
2
1
0
CAM 3.1
CAM 3.5 (Offline Met)
CAM 4.0
1 2 3 4 5 6 7 8 9 10 11 12
Month
47

7.2. Indirect and semi-direct
atmospheric forcing
7.3. Snow and ice forcing
48

7.4. Dynamical influence on
response to forcing
7.5. Summary
49

8. Linking sources to Arctic
radiative forcing
8.1. Introduction to modeling studies
conducted for this report
50

8.2. Emissions used
51

8.3. Model description
8.4. Model results
8.4.1. Contribution to change in BC
burden
52

Annual tropospheric burden in the Arctic, Mg
500
Arctic BC burden, Gg
1.3
400
300
200
0
United States
Canada
Russia
Nordic countries
Rest <strong>of</strong> World
100
0
Domestic
Energy+
Industrial+
Waste
Transport
Agricultural
Fires
Grass+
Forest Fires
Emission region
Model used
United States Canada Russia Nordic countries Rest <strong>of</strong> World Darker color - NCAR CCSM Lighter color - Oslo CTM2
8.4.2. Contribution to RF in the Arctic
53

90N
a
80N
70N
60N
50N
40N
30N
20N
10N
EQ
180 120W 60W 0
60E 120E 180
1 2 5 10 22 46 100 215 464 1000 ng BC / g ice
85N
b
60N
30N
0
30S
60S
85S
135W 90W 45W 0
45E 90E 35E
0
0.5
10521
20 50 100
ng BC / g ice
200
500
54

Atmospheric direct RF due to BC, mW/m 2
30
25
20
15
10
5
0
0
Domestic
Energy+
Industrial+
Waste
Atmospheric direct RF due to BC+OC, mW/m 2
30
25
20
15
10
5
Domestic
Energy+
Industrial+
Waste
Transport
Transport
60° N to 90° N
Agricultural
Fires
60° N to 90° N
Agricultural
Fires
Emission region
Model used
United States Canada Russia Nordic countries Rest <strong>of</strong> World Darker color - NCAR CCSM Lighter color - Oslo CTM2
Grass+
Forest Fires
Grass+
Forest Fires
RF due to snow/ice BC, mW/m 2
30
25
60° N to 90° N
20
15
10
5
0
Domestic
Energy+
Industrial+
Waste
Transport
Agricultural
Fires
Grass+
Forest Fires
Emission region
Model used
United States Canada Russia Nordic countries Rest <strong>of</strong> World Darker color - NCAR CCSM Lighter color - Oslo CTM2
55

RF due to BC+OC (60° N to 90° N), mW/m 2
80
Nordic United Canada Russia Rest <strong>of</strong>
countries States
World
60
40
20
0
Atmospheric
direct (BC+OC)
Domestic
Agricultural Fires
Snow/ice (BC)
Energy + Industrial + Watse
Grass + Forest Fires
Transport
8.4.3. RF per unit emission
Direct RF per unit BC emission, mW/m 2 per Gg/y
0.4
60° N to 90° N
0.3
0.2
0.1
0
Domestic
Energy+
Industrial+
Waste
Transport
Agricultural
Fires
Grass+
Forest Fires
Emission region
Model used
United States Canada Russia Nordic countries Rest <strong>of</strong> World Darker color - NCAR CCSM Lighter color - Oslo CTM2
Snow/ice RF per unit BC emission, mW/m 2 per Gg/y
0.4
60° N to 90° N
0.3
0.2
0.1
0
Domestic
Energy+
Industrial+
Waste
Transport
Agricultural
Fires
Grass+
Forest Fires
Emission region
Model used
United States Canada Russia Nordic countries Rest <strong>of</strong> World Darker color - NCAR CCSM Lighter color - Oslo CTM2
56

RF per unit BC emission, mW/m 2 per Gg/y
1.0
Nordic
countries
United
States
Canada Russia Rest <strong>of</strong>
World
RF, mW/m 2
70
60
60° N to 90° N
0.8
0.6
Snow/ice (BC)
50
40
30
Atmospheric direct (BC+OC)
Snow/ice (BC)
20
0.4
10
0.2
0
Atmospheric
direct (BC+OC)
0
RF per unit BC emission, mW/m 2 per Gg/y
0.25
60° N to 90° N
Domestic Energy + Industrial + Watse
Agricultural Fires Grass + Forest Fires
Transport
0.20
0.15
0.10
0.05
8.4.4. RF by latitude <strong>of</strong> emissions
0
90° S – 40° N 40° – 50° N 50° – 60° N 60° – 90° N
Source region
8.4.5. RF due to projected increases in
global and Arctic shipping
57

RF, mW/m 2
7
6
5
4
3
2
1
0
RF per unit BC emission, mW/m 2 per Gg/y
0.8
0.6
0.4
0.2
0.0
Global
2005
Global
2030
Global
2050
Atmospheric
direct (BC+OC)
Arctic
2005
60° N to 90° N
60° N to 90° N
Arctic
2030
Snow/ice (BC)
Arctic
2050
8.4.6. Relation between RF and
temperature change
RF per unit BC emission, mW/m 2 per Gg/y
2.0
Normalized net
forcing for Arctic Council
Nation emissions
1.5
1.0
Normalized net
forcing for emissions
by latitude band
Normalized net
forcing for projected
shipping emissions
Within
Arctic
0.5
Global
0.0
United States
Canada
Russia
Nordic countries
Rest <strong>of</strong> World
90° S – 40° N
40° – 50° N
50° – 60° N
60° – 90° N
2005
2030
2050
2005
2030
2050
58

Response, °C, per unit positive global RF, wM/m 2
0.45
60° N to 90° N
0.30
0.15
0
-015
28°-90° S 28° S-28° N 28°-60° N 60°-90° N
Forcing location
<strong>Carbon</strong> dioxide
BC without AIE BC Sulfate without AIE Sulfate Ozone
59

9. Summary findings on
impacts <strong>of</strong> black carbon
on Arctic climate and
relevance to mitigation
actions
60

10. Information and science
needs
10.1. Recommendations for improved
characterization <strong>of</strong> spatial and
vertical distribution <strong>of</strong> BC and
OC in the Arctic environment
and deposition processes
61

10.2. Recommendations for emissions
information
10.3. Recommendations for model
development, evaluation and
application
62

63
References

64

65

66

67

68

69

Abbreviations
70