Emissions of Regional and Global Air Pollutants

David StreetsArgonne National Laboratory, U.S.A.

EPA Workshop on Climate Change and Air Quality

Research Triangle Park

December 3-5, 2001

Sources of airborne pollution in developing countries are many: home cooking, power generation, industry, traffic, and

biomass burning

Important species in the Asian atmosphere and their origin

Particles like BC and OC (residential fuel combustion, diesel vehicles) SO2 and sulfate aerosol (coal combustion) CO2, CH4, and other greenhouse gases (fossil fuels, agriculture) NOx, nitrate aerosol, and other nitrogen compounds (vehicles) Non-methane volatile organic compounds (NMVOC) (all kinds) Ozone (formed from NOx and NMVOC) Ammonia (agriculture mainly) Trace elements such as Hg (fossil-fuel combustion) Mineral dust (wind-blown from arid and semi-arid regions)

Small particles like BC, OC, and SO4 are implicated in regional- and continental-scale problems and global warming. Tropospheric ozone is also now recognized as an important greenhouse gas.

Methodology for Asian Emission Estimates

Energy Use

RAINS-AsiaModel

EmissionControls

Activitydata

Other human activities

Biomassburning

Natural emissions

Biogenic, Volcanic...Emission

factors, Regulations

Anthropogenic emissions

“Total” emissions

Coordinated emission profiles for Asia for the year 2000 are being constructed for TRACE-P and ACE-Asia

SO2 NOx* CO NMVOC** BC OC NH3

China 20.8 9.8 98.2 17.2 1.01 3.3 13.5

Other East Asia 2.3 4.5 12.4 4.2 0.10 0.31 0.92of which, Japan 0.8 2.2 4.5 1.9 0.04 0.05 0.35

Southeast Asia 3.3 4.6 65.8 17.7 0.55 3.2 3.4

Indian Subcontinent 7.2 5.3 68.3 13.7 0.73 3.6 9.6of which, India 5.5 4.5 53.6 10.8 0.56 2.8 7.4

International Ships 1.1 1.3 0.1 0.0 0.07 0.05 0.0

Asia Total 34.8 25.6 244.8 52.7 2.46 10.4 27.6

Notes: Summary emissions as of 10/25/01. Full biomass burning emissions are included, based on "typical, annual" values. * As NO2. **Anthropogenic emissions only (no biogenic NMVOC emissions).

SUMMARY OF ANTHROPOGENIC EMISSIONS IN ASIA

RegionYear 2000 Emissions (Tg)

Updates will be posted on our University of Iowa web site:http://www.cgrer.uiowa.edu/people/carmichael/ACESS/Emission-data_main.html

The distribution of emissions among source types varies considerably

0%

20%

40%

60%

80%

100%

SO2 NOx NMVOC CO BC OC NH3

Agriculture

Transport

Industry

Power

Domestic

BiomassBurning

Coal-burning cook stovesin Xian, China

Inefficient combustion in Asia produces large quantities of CO, CH4, NMHC, and BC

0.0001

0.01

1

100

Power GenCoal

IndustrialCoal

ResidentialCoal (Bitum)

ResidentialCoal (Anthra)

Res. Coal(Lignite)

Diesel

Emis

sion

fact

or (g

/kg)

Currently usedThis review

New investigations have forced a re-assessment of BC emission factors (Streets et al., Atmos. Environ., 35, 4281, 2001)

Black carbon emissions in China are distributed in a broad SW to NE swath across the rural heartland

TRACE-P griddedemissions at 5 minsx 5 mins resolution

INDOEX measurements show unusually high BC concentrations off the Indian continent (Dickerson et al., 2001)

0.00

0.50

1.00

1.50

2.00

2.50

50 100 150 200 250 300 350CO (g m-3)

BC

(g

m-3

)

INDOEX (Spring)Mace Head (Spring)FME (annual)

High BC may be due tobiomass burning, vehicle

fuel adulteration, small coal combustors or…?

There has been a remarkable change in air pollution emissions in China since 1996, due to:

The economic downturn in 1997-98 in East and Southeast Asia Reform of industry and power, leading to a reduction in coal use Structural shift away from heavy industry towards high-tech

industries and services Improvements in energy efficiency and fuel quality Closing of many small, inefficient, high-sulfur coal mines, reducing

the over-supply of coal Slowdown in electricity demand, due to higher electricity prices Opening up of electricity and coal markets Residential fuel switching from coal to electricity and gas in (large)

cities Technological progress in the energy-intensive sectors

(Source: Sinton and Fridley, Energy Policy, 28, 671, 2000)

Future SO2 emissions in Asia are likely to be much lower than the latest IPCC forecasts

Long-term emission changes in Asia are reflected in sulfate aerosol measurements at Midway Island (Prospero et al., 2001)

Annual trends in CO2 and CH4 emissions in China (Streets et al., Science, November 30, 2001)

Indexed trends in greenhouse-gas emissions in China

The net effect of theseemission changes on global

mean temperatures is anINCREASE, due to the

dominant effect ofthe sulfate aerosol

NMVOC emission profiles are very different around the world

0%

20%

40%

60%

80%

100%

China1995

China2020

EasternEurope1990's

EasternEurope

2020

Japan1990's

Japan2020

WesternEurope1990's

WesternEurope

2020

Stationary combustion Fossil fuel processing & distributionSolvent use & chemical industry TransportMiscellaneous

NMVOC emissions in China come from varied sources and are growing fast (Klimont et al., Atmos. Environ., 2001)

Sector 1990 1995 2000 2010 2020

Stationary combustion 5804 5509 5225 5004 4557Extraction, processing and handling of fossil fuels 517 707 924 1293 1755Chemical industry 78 134 206 369 528Solvent use (excluding paint use) 580 761 1245 2059 2828Paint use 640 1031 1472 2235 3039Transport 2317 3567 5071 4495 3559Waste disposal 868 889 880 860 837Miscellaneous 302 521 611 896 1106

Total 11105 13120 15634 17211 18209

NMVOC Emissions are Speciated into 19 Reactivity Classes

0

5

10

15

20

25

30

Ethane

Propan

e

Butane

s

Pentan

es

Other A

lkane

s

Ethene

Propen

e

Termina

l Alke

nes

Inter

nal A

lkene

s

Acetyl

ene

Benze

ne

Toluen

e

Xylene

s

Other A

romati

cs

HCHO

Other A

ldehy

des

Ketone

s

Haloca

rbons

Other

Shar

e (%

)

China

Other East Asia

Rest of Asia

Based on full molecular weights

Ammonia emissions are high in Asia (due to animals and fertilizer use) and important for the formation of (NH4)2SO4

TRACE-P griddedNH3 emissions

Biomass burning can have a large influence on hemispheric air quality; this figure shows the Siberian forest fires of 1998

TOMS AI data show progression of Siberian smoke plume across East Asia and the Pacific Ocean

AVHRR fire count image for 3/28/2001 showed no burning over SE Asia and China, due to clouds ….

…. however, TOMS AI data for the same day show heavy aerosol over southern China ….

…. so we can use the TOMS AI data to “fill in” missing AVHRR data (cautiously!)

On April 16, 1998, a huge dust cloud formed over China and was pushed eastward by a frontal system (NASA SeaWiFS) ….

…. nine days later, some of the dust reached the California coastline (on April 25, 1998)

TRACE-P (Transport and Chemical Evolution over the Pacific) ACE-Asia (Asian Pacific Regional Aerosol Characterization

Experiment)

Experimentalmeasurements

Theoreticalmodeling

On 3/10/2001, the TRACE-P DC-8 traversed plumes of man-made pollution from China (red) and biomass burning from

Southeast Asia (orange)

Elevated biomass-burning plume from

Southeast AsiaLow-level pollution

from mainland China

Chemical forecasting was able to successfully predict pollution features during TRACE-P (BC)

Research Needs for Regional and Global Emissions

more source testing in developing countries to produce reliable emission factors

the development of emitter inventories (e.g., vehicles) and surveys to gauge the representativeness of emission factors

greater consistency of estimates of primary particulate emissions, particularly BC and OC, by size and chemical composition

special investigations of emissions/modeling/observation inconsistencies (e.g., Asian CO and BC)

improve the use of satellite data to develop fine temporal and spatial resolution of biomass burning

“narrow the gaps” by studying unconventional sources: coal-mine fires, field combustion, waste burning……

Experimental programs like TRACE-P and ACE-Asia promise new insights into pollutant release, transformation, and transport