Influence of future emissions and climate on atmospheric
PAH transport
Carey Friedman MIT Noelle E. Selin MIT Yanxu Zhang University of Washington
Polycyclic aroma+c hydrocarbons (PAHs): Why do we care? • Probable/possible human carcinogens (U.S. EPA) • Travel long distances in the air (measured in Arc+c) • Exposures include inhala+on
Ques+ons in this study: • What is the rela+ve influence of future (2050) climate and
future emissions on PAH transport? • How might we diagnose climate versus emissions influences?
The GEOS-‐Chem PAH model
Gas phase
OH Oxida+on
OC-‐Bound
Emissions
BC-‐bound
Wet dep Dry dep
O3 Oxida+on O3 Oxida+on
Wet dep Dry dep Wet dep Dry dep
Emissions: 1) Primary 2) Secondary
Friedman and Selin ES&T 2012
Phenanthrene (PHE) Pyrene (PYR) Benzo[a]pyrene (BaP)
Gas Par+culate
North America
Europe Russia
South Asia
East Asia
This study: future emissions and future climate We scale the top (70%) global anthropogenic sources from the
Zhang and Tao (Atmos. Environ., 2009) inventory from ~2000 to 2050:
Tradi+onal biomass burning (57%) Domes+c coal burning (4%) Vehicle emissions (5%) Coke produc+on (4%)
EMISSIONS GO DOWN
Par+cles: OC ê BC ê Oxidants: OHé O3é
This study: future emissions and future climate
Present climate Future climate (IPCC A1B)
Mean of simulated years: 1997-‐2003 2047-‐2053
Precipita+on
é 5%
Temperature
é 1.6 C
Wildfire emissions (17%)
We simulate present and future climate with GISS GCM meteorology from the GCAP project:
é or no change
Par+cles: OC ê BC ê Oxidants: OHê O3ê
Results: Vola+lity Maiers
< > ng/m3
< > ng/m3
< > ng/m3
< > ng/m
< > ng/m
< > ng/m
Phenanthrene (vola+le) Benzo[a]pyrene (non-‐vola+le) 2050-‐2000:
Emissions
Climate
Emissions &
Climate
-‐23%
+4%
-‐19%
-‐37%
-‐3%
-‐38%
Change in mean northern hemisphere concentra+ons
CLIM
ATE PE
NAL
TY: 19%
CLIMATE BEN
EFIT: 5%
The Arc+c is a priority for resolving climate vs. emissions influences
0o
15oN
30oN
45oN
60oN
75oN
90oN
0 80 160 240 320 400 480 PHE/BaP
0o
15oN
30oN
45oN
60oN
75oN
90oN
0 15 31 48
0o
15oN
30oN
45oN
60oN
75oN
90oN
0 16 32 48
CONTROL
2050 EMISSIONS
2050 CLIMATE
A
B
C
PHE/BaP
PHE/BaP
5
50
500
PHE/Ba
P
Measured 2000 Control Simula+on 2050 Emissions 2050 Climate
En+re Arc+c 60-‐90N n=3
High Arc+c 80-‐90N n=1
Acknowledgements Leading Technology and Policy Ini+a+ve, MIT NSF Atmospheric Chemistry Program Grant #1053648 NSF Office of Polar Programs Grant #1203526 Shiliang Wu, Michigan Tech Eric Leibensperger, SUNY Plaisburgh The Selin Group, MIT
Related literature: PAH model descrip+on and evalua+on:
Friedman and Selin. 2012. Long-‐range atmospheric transport of Polycyclic Aroma+c Hydrocarbons: A global 3-‐D model analysis including evalua+on of Arc+c sources. Environ. Sci. Technol. 46:9501.
2004 (present) PAH emissions:
Zhang and Tao. 2009. Global atmospheric emission inventory of PAHs for 2004. Atmos. Environ. 43:812. Future PAH vehicle emissions:
Shen et al. 2011. Global +me trends in PAH emissions from motor vehicles. Atmos. Environ. 45:2067. Projec+ons of energy use:
Interna+onal Energy Agency. 2010 and 2011. “World Energy Outlook.” Projec+ons of wildfire index changes:
Liu et al. 2009. Trends in global wildfire poten+al in a changing climate. Forest Ecol. Manag. 259:685. Malevsky-‐Malevich et al. 2008. An assessment of poten+al change in wildfire ac+vity in the Russian boreal forest zone induced by climate warming during the twenty-‐first century. ClimaDc Change. 86:463.
Methods for par+cle and oxidant concentra+on projec+ons:
Wu et al. 2008. Effects of 200-‐2050 changes in climate and emissions on global tropospheric ozone and the policy-‐relevant background surface ozone in the United States. J. Geophys. Res. 113:D18312. Streets et al. 2004. On the future of carbonaceous aerosol emissions. J. Geosphys. Res. 109:D24212. Pye et al. 2009. Effect of changes in climate and emissions on future sulfur-‐nitrate-‐ammonium aerosol levels in the United States. J. Geophys. Res. 114:D01205
Image credits: Eric DeRienzo Mark Thiessen