The DELTA Group

for the Detection and Evaluation of the Long-Range Transport of Aerosols

See our latest photos
from the Roseville site!

Department of Applied Science

World Trade Center
Who We Are
DQAP Download



Recent Publications

News and Notes

Olympics Air Quality Update

Weather, Beijing PM10 and HYSPLIT Trajectory Analysis, MODIS Satellite Pictures, Washington Beijing Comparison

New book (Jan, 2017) “I can breathe clearly now. Protecting yourself from air pollution”, EditPros, Davis

The $750,000,000 funding for the health of the workers at the World Trade center site that I worked to get was just renewed for 5 more years.

A new science fiction book rich in accurate global climate science, “Greenhouse Redemption of the Planet Kraal”, EditPros, Davis

Pesent Consultant to the CA Department of Justice on the cleanup of the Exide battery recycling plant in Los Angeles.

NSF program collecting and analyzing measuring aerosols on the Greenland Summit site, started in 2003, and renewed into 2021, with Dr. Nick Spade, co PI. The purpose of the work is twofold: 1) understanding the dust levels present at the times dust appears in the Greenland cores, especially around the Younger Dryas ice age, and 2) evaluating the impact of transported anthropogenic aerosols into the Arctic on the Arctic climate.

2010 – 2016
Contracts (3) with US EPA on aerosols and highways in Detroit and Cleveland.

2010 – 2012
Three new science fiction books rich in accurate science, following an asteroid strike on the Earth with only 3 days warning: “Ark Asteroid Impact”, “Ark: Diaspora”, and “Ark: Return to Eden”.

2008 – 2014 Appointed member of the CA Inspection and Maintenance Review Committee (IMRC) overseeing Smog Check II.

2008 - 2010 Contract with CalTrans on the impact of sanding and salting on the water quality of Lake Tahoe

Contract on emissions from the Terminal Island car shredder, CA Department of Toxic Substances Control

September 2005
Rachel DuBose leaves the DELTA Group for her new job at the Sacramento Metropolitan Air Quality Management District. Good luck Rachel!

July 2005
(26.7.2005) The American Lung Association of Sacramento-Emigrant Trails Health Effects Task Force publishes "Sacramento Interstate-5 Aerosol Transect Study" (Watt Avenue Particulate Study/Tailpipe Pollution).

(26.7.2005) The Sacramento Bee publishes "Alert on tailpipe smoke: Big pollution source falls under radar, experts say" based on Dr. Cahill's studies of particulate pollution in the Sacramento region.


2017 List of Recent Publications

Thomas A. Cahill, David E. Barnes, Jonathan A Lawton, Roger Miller, Nicholas Spada, Robert D. Willis and Sue Kimbrough, Transition metals in coarse, fine, very fine and ultra-fine particles from an interstate highway transect near Detroit, Atmospheric Environment (Sept, 2016)

Thomas A. Cahill, David E. Barnes, Leann Wuest, Sean Barberie, David Gribble, David Buscho, Jason Snyder, Roger S. Miller, and intern Camille De la Croix, Artificial Ultra-fine Aerosol Tracers for Highway Transect Studies, Atmospheric Environment 136, 21 – 42 (2016)

Sean R. Barberie, Christopher R. Iceman, Catherine F. Cahill, and Thomas M. Cahill,Evaluation of Different Synchrotron Beamline Configurations for X ray Fluorescence Analysis of Environmental Samples, Anal. Chem. 2014, 86, 8253−8260,

Cahill, Thomas A., , David E. Barnes, Nicholas J. Spada, Seasonal variability of ultra-fine metals downwind of a heavily traveled secondary road, Atmospheric Environment 94 173 - 179 (2014)

Cahill, Thomas M., Annual cycle of size-resolved organic aerosol characterization in an urbanized desert environment, Atmos. Environ. 71, 226 – 233 (2013)

Baldauf, Richard, Greg McPherson, Linda Wheaton, Max Zhabg, Tom Cahill, Chad Bailey, Christina Hemphill-Fuller, Earl Withycombe, and Kori Titus, Integrating Vegetation and Green Infrastructure into Sustainable Transportation Plannin, Transportation Research Bulletin, National Academy of Sciences (2013)

Cahill, Thomas M., and Thomas A. Cahill. Seasonal variability of particle-associated organic compounds near a heavily traveled secondary road. Aerosol Science and Technology, (2013) doi: 10.1080/02786826.2013.857757

Cahill, Thomas A.; Cliff, Steven S.; Portnoff, Lee; Perry, Kevin D.; The DELTA Group; American Lung Association of Sacramento-Emigrant Trails; "Sacramento Interstate-5 Aerosol Transect Study". July 2005.

Gertler, Alan; Bytnerowicz, Andrzej, Cahill, Thomas A.; Arbaugh, Michael; Cliff, Steven; Kahyaoglukoracin, Julide; Tarnay, Leland; Alonso, Rocio; Fraczek, Witold; Sources of Atmospheric Pollutants in the Lake Tahoe Basin. California Agriculture Magazine. 2005

Perry, Kevin D. Cliff, Steven S. Jimenez-Cruz, Michael P. Evidence for hygroscopic mineral dust particles from the Intercontinental Transport and Chemical Transformation Experiment. Journal of Geophysical Research, Volume 109, D23S28, 2004