Global and Global Dust and Smokeover

North America

Rudolf B. HusarWashington University, St. Louis, MO

Seminar atForschungszentrum Juelich, October 16, 2007 Germany

The BIG PICTURE

How do humans perturb the composition of the

atmosphere?

Opportunities & Challenges

What is the magnitude of the anthropogenic perturbation of natural processes?

Windblown Dust Volcanic Emissions

Industrial Aerosols

Aerosol are Indicators of Major Biogeochemical Processes

Chistian Junge: “In the 50’s wherever you looked there was something interesting”

Smoke from Fires

Early Satellite Detection of Manmade Haze, 1976

Regional Sulfate Haze

over the Midwest

Low Visibility Hazy ‘Blobs’Lyons W.A., Husar R.B. Mon. Weather Rev. 1976

SMS GOES June 30 1975

Early Observation-Based Aerosol Climatology AVHRR:

Tropics Highest AOT; Dust and Smoke DominateWhere is the Human Impacts??

Husar, Prospero, Stowe, 1997

MISR Seasonal AOT (MISR Team)

Recent Satellite Data Show All Major

Dust and Smoke Emission Regions by Season

US Air Pollution Control Goal:Attain natural conditions by 2064

Industrial Sulfur Emission Density

The regional hot-spots for industrial sulfur emissions are in

E. North America,

Europe and

E. Asia

US SOx Emission

Shifts of Attention: Local, Regional, Global Pollution

Before 1950s:

LocalSmoke, Fly ash

Post- 2000s:

GlobalGlobal Change

1970s-1990s:

RegionalAcid Rain, Haze

Future???

Multi-Scale Approach?

The Asian Dust Event of April 1998

On April 19, 1998 a major dust storm occurred over the Gobi Desert

The dust cloud was seen by SeaWiFS, TOMS, GMS, AVHRR satellites

The transport of the dust cloud was followed on-line by an an ad-hoc international group

China

Mongolia

Korea

Asian Dust Cloud over N. America

On April 27, the dust cloud arrived in North America.

Regional average PM10 concentrations increased to 65 g/m3

Asian Dust 100 g/m3

Hourly PM10

IMPROVE Fine Particle Dust Concentrations

 

April 25, 1998 April 29, 1998 May 2, 1998

April 1998 Asian Dust event detection, analysis, reporting by ad-hoc international virtual (web-based) workgroup!!

A driver for informatics effort on data sharing and collaboration

What kind of neighborhood is this anyway?

May 9, 1998 A Really Bad Aerosol Day for N. America

Asian Smoke

C. American Smoke

Canada Smoke

Sahara PM10 Events over Eastern USMuch previous work by Prospero, Cahill, Malm, Scanning the AIRS PM10 and IMPROVE chemical

databases several regional-scale PM10 episodes over the Gulf Coast (> 80 ug/m3) that can be attributed to Sahara.

June 30, 1993

The highest July, Eastern US, 90th percentile PM10 occurs over the Gulf Coast ( > 80 ug/m3)

Sahara dust is the dominant contributor to peak July PM10 levels.

July 5, 1992

June 21 1997

Seasonal Fine Aerosol Composition, E. USUpper Buffalo Smoky Mtn

Everglades, FLBig Bend, TX

The two dust peeks at Big Bend have different Al/Si ratiosDuring the year, Al/Si = 0.4 In July, Al/Si reaches 0.55, closer to the Al/Si of the Sahara dust (0.65-0.7) The spring peak is identified as as ‘Local Dust’, while the July peak is dominated by Sahara dust.

Attribution of Fine Dust (<2.5m) Local

and Sahara

• In Florida, virtually all the Fine Particle Dust appears to originate from Sahara throughout the year

• At other sites over the Southeast, Sahara dominates in July

• The Spring and Fall dust is evidently of local origin

Satellites detect dust most storms in near real time

The MODIS sensor on AQUA and Terra provides 250m resolution images of the dust storm

Visual inspection reveals the dust sources at the beginning of dust streaks.

The NOAA AVHRR sensor highlights the dust by its IR sensors

In the TOMS satellite image, the dust signal is conspicuously absent – too close to the ground

High Wind Speed – Dust Spatially Correspond

The spatial/temporal correspondence suggests that most visibility loss is due to locally suspended dust, rather than transported dust

Alternatively, suspended dust and ‘high winds’ travel forward at the same speed

Wind speed animation; Bext animation. (material for model validation?)

PM10 > 10 x PM25During the passage of the dust cloud over El Paso, the PM10 concentration was

more than 10 times higher than the PM2.5

AIRNOW PM10 and Pm25 data

PM10 and PM25, El Paso, Feb. 19 2004 - AIRNOW

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Schematic

Link to dust modelers for faster collective learning?

Origin of Fine Dust Events over the US

Fine dust events over the US are mainly from intercontinental transport

Dust is seasonal with noise

Random short spikes added

Sulfate is seasonal with noiseNoise is by synoptic weather

Fine Dust over North America

• The dust baseline concentration is has a 5x seasonal amplitude from 0.2 to 1 ug/m3• The dust events (determined by the spike filter) occur in April/May and in July• The two April/May and the July peak in avg. dust is due to the events

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EventsBaselineTotal

Sahara Events

Asian + Local Events

Pattern of Fires over N. AmericaThe number of ATSR satellite-observed fires peaks in

warm seasonFire onset and smoke amount is unpredictable

Fire Pixel Count:

Western US

North America

May 15, 1998

• Fire locations detected by the Defense Meteorological Satellite Program (DMSP) sensor.

• Smoke is detected by SeaWiFS and TOMS (green) satellites and surface visibility data, Bext

Smoke from Central American Fires

• The smoke plume extends from Guatemala to Hudson May in Canada

• The Bext values indicate that the smoke is present at the surface

PM10 Concentrations During the Smoke Event

A füstfelhő útjában mindehol a megengedett érték feletti aeroszol koncentrációt okozott, és a levegő homályossága gátolta a légiforgalmat

Smoke Aerosol and Ozone During the Smoke Episode – Inverse Relationship

The surface ozone is generally depressed under the smoke cloud

Extinction Coefficient (visibility)

Surface Ozone

May-June 2003 Siberian Fires

Aircraft Detection of Siberian Forrest Smoke near Seattle, WA

Jaffe et. al., 2003

Seasonal cycle in mean afternoon surface O3 over the US

Based on the Harvard global model and surface observations

Regional pollution: 10-30 ppbv

Hemisph. pollution: 5-15 ppbv

Natural ozone: 15-25 ppbv

Stratospheric ozone: 0-10 ppbv

Fiore et al., JGR in prep.

Long Range Transport of Combustion Products

• F. Bacon (ca 1600): The Gasgogners have complained to the King of of England that smoke from the burning of seaweed in Sussex has spoiled the wine flowers…

• Wargentin and Gadolin (1767): Forest fires in Russia and Finland are causing regional haze in Europe. Used back-trajectories.

Thoughts on Atmospheric Dust

• Dust exists even on the tops of the highest mountains. It settles slowly in clear weather but is quickly washed down by rain and snow

• Some dust is from the pulverization of road and field surfaces

• Other dust comes from materials in the activity of mankind but whence arises the dust observed by means of sunbeams?

Constantin Rafinesque, 1818

Gas-Particle Conversion

• We know that sulfur, ammonia, etc. can be formed by sublimation of gases

• That smoke soot, volcanic productions, meteorites, earths, and even stones or metals may be spontaneously combined by a casual meeting of gaseous emanations.

• It is not, therefore, difficult to conceive how dusty particles may be formed in the great chemical laboratory of our atmosphere.

Rafinesque, 1820

Pattern of Peat Smoke Pollution in NC Europe

Dissertation by Kemp (1914)

•Agricultural peat burning begun early in the 1800s and peaked in 1860s.• The regional haze covered much of the flatland north of the Alps extending to Paris.

• Due to public pressure and diminishing swamp land the practice stopped by the 1870s

Peat Smoke Episode, Prestel, 1861

• A century long debate begun on the causes of the thick haze: local vs long range transport; smoke, dust, earthquakes...

Establishing Source-Receptor Relationship

Egen, 1828

Smell: [composition] Temporal Trend

Decay with Distance Wind Direction

Direct Evidence

Trajectory