Timothy Garrett, Ph.D.

Timothy Garrett

Associate Professor, Atmospheric Sciences

Atmospheric Sciences
University of Utah
135 S 1460 East Rm 819 (WBB)
Salt Lake City, Ut 84112-0110

Office: 821 WBB
Office Phone: (801) 581-5768
Email: tim.garrett@utah.edu
>> Curriculum Vitae
My Website: www.inscc.utah.edu/~tgarrett/ACCS.html

2000 Ph.D. Atmospheric Sciences University of Washington
1995 M.S. Atmospheric Sciences University of Washington
1992 B.Sc. Physics University of Waterloo


My research focus is in the field of cloud physics. Clouds are interesting because they display such an extraordinarily wide range of interactive physical processes, and understanding these is critical for improving weather and climate forecasts. My work also includes development of simple physical models for understanding civilization growth. While the two may seem disconnected, it looks like both clouds and civilization are complex systems that evolve according to the same non-equilibrium thermodynamic rules.

Much of this work is done in collaboration with graduate students in the ACCS group. Some involves pencil and paper, PCs or parallel computing environments. There is also laboratory work. With engineer Cale Fallgatter, we build instruments for photographing snowflakes in freefall in the Cloud Physics Laboratory at the University of Utah. These are deployed to our High Altitude Research Laboratory for Diversity in Snow (HARoLDS) at Alta Ski Area in Utah s Wasatch Front.

When not involved in research, I teach graduate and undergraduate classes in Cloud Physics, Atmospheric Radiation and Thermodynamics, and I serve as a co-editor for the Copernicus open access journal Atmospheric Chemistry and Physics.

Selected Publications:

Observational quantification of the optical properties of cirrus cloud  (Book Section), 2008
[citation]  [text]

Acceleration by aerosol of a radiative-thermodynamic cloud feedback influencing Arctic surface warming  (Journal Article), 2009
[citation]  [text]

Are there basic physical constraints on future anthropogenic emissions of carbon dioxide?  (Journal Article), 2009
[citation]  [abstract]  [text]

An evolving history of Arctic aerosols  (Journal Article), 2008
[citation]  [text]

Evaluation of the aerosol indirect effect using satellite, tracer transport model, and aircraft data from ICARTT  (Journal Article), 2008
[citation]  [text]

Ground-based remote sensing of precipitation in the Arctic  (Journal Article), 2008
[citation]  [abstract]  [text]

Hazy perspectives of Early Arctic Explorers  (Journal Article), 2008
[citation]  [text]

Short-lived pollutants in the Arctic: their climate impact and possible mitigation strategies  (Journal Article), 2008

Comments on "Effective radius of ice cloud particle populations derived from aircraft probes"  (Journal Article), 2007
[citation]  [text]

Evaluation of the aerosol indirect effect using satellite, tracer transport model, and aircraft data from ICARTT  (Journal Article), 2007
[citation]  [abstract]  [text]

Extinction coefficients retrieved in deep tropical ice clouds from lidar observations using a CALIPSO-like algorithm compared to in-situ measurements from the Cloud Integrated Nephelometer during CRYSTAL-FACE  (Journal Article), 2007

Observing cirrus halos to constrain in-situ measurements of ice crystal size  (Journal Article), 2007
[citation]  [text]

Convective formation of pileus cloud near the tropopause  (Journal Article), 2006
[citation]  [text]

Effects of cirrus near the tropopause on anvil cirrus dynamics  (Journal Article), 2006
[citation]  [abstract]  [text]

Increased Arctic cloud longwave emissivity associated with pollution from mid-latitudes  (Journal Article), 2006
[citation]  [abstract]  [text]

Quantifying wet scavenging processes in aircraft observations of Nitric Acid and CCN  (Journal Article), 2006
[citation]  [abstract]  [text]

Evolution of a Florida cirrus anvil  (Journal Article), 2005
[citation]  [text]

Small, highly reflective ice crystals in low-latitude cirrus  (Journal Article), 2003
[citation]  [text]

Research Statement

Clouds play a key role in climate by removing pollutants from the atmosphere, shielding the Earth from sunlight, and by acting as pistons in the atmospheric heat engine. But they are also extraordinarily dynamic over a vast range of interacting scales in time in space, and this makes them difficult to understand. Is their role in climate fundamentally simple (which would be nice) or impossibly complex (a cause for despair)? Our group works to tease from clouds their contributions to various atmospheric chemical, dynamic, microphysical and radiative processes.

A second focus is development of a thermodynamic basis for interpreting the evolution of the global economy, and its relationship to atmospheric concentrations of carbon dioxide. Central to the model is the finding that civilization's economic value or wealth, when adjusted for inflation, is linked to its rate of primary energy consumption through a constant.

Research Keywords, Regions of Interest and Languages:

Keywords: Atmospheric Physics (2); Climate Change (10); Cloud Physics (4); Energy Economics (2); Chemical Transport; Global Change (3); Greenhouse Gases (2); Precipitation (5)
Regions: Arctic Ocean (2)

Research Projects

Aerosol-cloud-climate interactions [details]

Project Web Site:www.inscc.utah.edu/~tgarrett/Projects/Arctic%20pollution.html

Project Grants: Evaluation of Aerosol-Cloud-Radiation Processes and Feedbacks in the Alaskan Arctic: NSF 2007

Snowflake Imagery in the Wasatch Front

Project Web Site:www.inscc.utah.edu/~tgarrett/Snowflakes/Snowflakes.html

The role of cloud-radiation interactions in cirrus [details]

Project Web Site:www.inscc.utah.edu/~tgarrett/Projects/Cloud%20dynamics.html

Project Grants: Evaluating tropical and mid-latitude cirrus properties using co-incident satellite and aircraft sensors: NASA 2008

Thermodynamics of Civilization Growth [details]

Where does money get its value? What physically is economic wealth? For studies of atmospheric science, this is a highly relevant question because as the economy grows, so do its emissions of carbon dioxide. Increasing concentrations of atmospheric carbon dioxide are changing the infrared opacity of the atmosphere, making increasingly profound long-term changes to global climate. My work is showing how economics can by linked to physics through a simple thermodynamic relationship that ties global economic wealth (or capital) to civilization's rate of primary energy consumption. Establishment of this relationship enormously simplifies calculations of the economic costs that are required to limit anthropogenic carbon dioxide emissions.
Project Web Site:www.inscc.utah.edu/~tgarrett/Economics/Economics.html

Courses I Teach

ATMOS 6020 Fundamentals of Physical Meteorology
ATMOS 6680 Atmospheric Radiation
ATMOS 7810 Graduate Seminar

Last Updated: 6/19/14