Atmospheric Science Programs and Research UNR has both undergrad and grad programs in Atmospheric Science. Prof. Arnott (Physics) and 25 faculty members.

Post on 16-Jan-2016

215 Views

Category:

Documents

0 Downloads

Preview:

Click to see full reader

Transcript

Atmospheric Science Programs and Research• UNR has both undergrad and grad programs in Atmospheric Science.

• Prof. Arnott (Physics) and 25 faculty members from the Division of Atmospheric Sciences at the Desert Research Institute participate in the program.

• The programs have a very strong research emphasis.

• Areas of emphasis:– Atmospheric Physics, solar and infrared radiation transfer, cloud microphysics, instrumentation development. Solar and wind energy.– Atmospheric Chemistry, trace detetction of organic and inorganic air pollutants; Pollutant transport and evolution.– Meteorology and Climatology, Western regional climate center, Center for Climate and Fire Applications, local, regional, and global climate change.

Students of ATMS 360, Atmospheric Instrumentation, measuring the downwelling infrared radiation from the atmosphere. The strong

emission around 650 cm-1 is due to CO2 in the

atmosphere.

Places We Work

Burning Brazilian Forest near Ji Parana: PyrocumulusClimate impacts of large scale biomass burning aerosol.

Courtesy Michael Welling, SMOCC 2002, Sept 25

Pancakes Layers of Smoke from Siberian Forest Fires Observed Over North Central Oklahoma, 27 May 2003(Photo by Roy Woods, the CIRPAS Twin Otter Co-pilot)

Arnott, W. P., J. W. Walker, H. Moosmüller, R. A. Elleman, H. H. Jonsson, G. Buzorius, W. C. Conant, R. C. Flagan, and J. H. Seinfeld, (2006). Photoacoustic insight for aerosol light absorption aloft from meteorological aircraft and comparison with particle soot absorption photometer measurements: DOE Southern Great Plains climate research facility and coastal stratocumulus imposed perturbation experiments. Journal of Geophysical Research 111, D05S02, doi:10.1029/2005JD005964.

0.5 to 1 km thick

Example of a morning when the Mexico City Plume Goes South to Popocatepetl Volcano, hiding it.

near forward scattering by particlessca = 30 degrees

r << r ~ r >>

Dynamometer Vehicle Tests: How much does your car pollute?

Jet Exhaust: SERDP 2002, North Island CA

The Crew In Action, 1,600’ underground in a Nevada

Gold Mine…

Undergrad physics major Ian Arnold, and Arnott

Vehicle Used for the Tests

Photograph showing the haul truck in operation along with the air quality samplers. The photoacoustic EC instrument is housed in the vanilla colored box on the equipment rack and the Dustrak nephelometers are in blue. The filter samplers are up on the wall immediately to the right of the blue writing on the wall. The sample inlet for the photoacoustic instrument can be seen draped over the top of the laptop computer.

Example of our Atmospheric Research: Optics of woodsmoke from different

sources

The Fire Science Laboratory in Missoula Montana

DUAL WAVELENGTH PHOTOACOUSTIC INSTRUMENT, PATENTED AND LICENSED TO DMT, BOULDER CO.

Measurement of Light Absorption, Scattering, and Extinction with a Single Instrument

Wood Smoke Particles by Rajan Chakrabarty, DRI/UNR Graduate Student

Fire Science Laboratory, Missoula Montana.

• Instrumentation sampling wood smoke during FLAME Chamber burns

• Photoacoustic instruments

UNR AND COLORADO STATE

UNIVERSITY STUDENTS AND

FACULTY

Fuel Fuel Characterization Burn (Label)

Ponderosa Pine, dried needles and sticks conifer (pine) A, C

Lodge pole Pine, needles and twigs conifer (pine) L

Utah Juniper, foliage and sticks conifer (pine) I

Southern Pine, needles conifer (pine) P

Ponderosa Pine duff duff (pine) F

Alaskan Duff (feather moss) duff G

Southern California Manzanita flowering shrub H

Southern California Chamise flowering shrub B, D, N

Southeastern Wax Myrtle flowering shrub O

Utah Sage and Rabbitbrush, foliage and sticks flowering shrub J

Southern California Ceanothus flowering shrub S

Southeastern US Palmetto, leaves miscellaneous flowering plant R

Asian Rice Straw (Taiwan) miscellaneous flowering plant E

Puerto Rico Fern fern M

(Puerto Rico mixed woods) Q

(Lignin) K

Chamise

Rice Straw

Ponderosa Pine

The fuels burned

Optical Parameters for Analysis of Absorption and Scattering

• Single Scattering Albedo, ω – Ratio of Scattering to Extinction

– Dark, absorbing aerosol: ω<0.5• Diesel Soot: ω(550 nm)=0.3

– “White”, highly scattering aerosol: ω>0.85• Rice Straw fuel: ω(405 nm)=0.88

Optical Parameters for Analysis of Absorption and Scattering

• Ångström exponent of absorption, b

babs β 1∝⎟⎠⎞⎜

⎝⎛

⎟⎠⎞⎜

⎝⎛

=⎟⎠⎞⎜

⎝⎛

2

1

2

1

2

1

ln

)()(ln

λλ

λβλβ

λλ abs

abs

b

– Common assumption of Ångström exponent model: for Black Carbon b=1

– Diesel Soot: b=1

– Rice Straw: b(405/870)=2.8

W. P. Arnott, AAAR tutorial, Sept. 2007 19

Ångström Exponent of Absorbtion vs.Single Scattering Albedo at 405 nm

0

0.5

1

1.5

2

2.5

3

3.5

0.3 0.4 0.5 0.6 0.7 0.8 0.9 1ù (405 nm)

Ponderosa Pine,mixed fuels

Chamise

Rice Straw

Ponderosa Pine Duff

Alaskan Duff

So. CalifornianManzanita

Sage & Rabbitbrush

Lodgepole Pine,mixed fuels

Utah Juniper,foilage/twigs

Puerto Rico Fern

Wax Myrtle,branches/foilage

Southern Pine,needles

Palmetto

Ceanothus

b(405/870)

Flowering Shrubs: Chamise, Manzanita, Sage & Rabbitbrush

Fern (Puerto Rico), Rice Straw & Ceanothus (a flowering shrub)

Duff: Alaskan & Ponderosa Pine Duff

Pines: Southern Pine, Lodgepole Pine, & Ponderosa Pine

ω

top related