Earth Sciences Division (ESD) Department of Energy (DOE) Lawrence Berkeley National Laboratory (LBNL)

Earth Sciences Division Staff: Travis A. O'Brien

Travis Obrien

Travis A. O'Brien

Research Scientist

Climate Sciences Department



Phone: 510-495-8047

Fax: 510-486-5686


Biographical Summary

Travis O'Brien is a research scientist in the Climate Sciences Department.  His research centers on understanding the physical processes that determine the climates of various regions, and how such processes and regional climates may change in the future.  He is presently focused on the characterization, development, and application of climate models for studies of coastal climatology.

Research Interests

Climate models are our one of our primary tools for investigating climatological processes and for developing detailed theories about how the climate system works.  Climate modeling can be viewed as a cycle that has three main stages: model development, model characterization, and model application.  As observation- and model-based studies improve our understanding of the natural world, it is often necessary to improve climate models in order to investigate new questions; model development is the stage in which we build new information into our climate models.  It is important to understand the properties of these models in order to understand ways in which model phenomena may reflect natural phenomena; model the characterization, which includes model validation, is the stage in which we develop a thorough understanding of the model itself and of how well the model represents nature.  Climate model application is the stage in which we use a climate model to gain new understanding about how the natural climate system works.  Travis is involved in all three stages of climate model-based research.

Model Characterization

Travis is currently investigating how and why resolved cloud systems in the Community Atmosphere Model change with model resolution (O'Brien et al.; 2013, J. Climate). He is also developing a satellite-based climatology of coastal fog for the purposes of climate model evaluation and for climate process studies. He has published studies on the impact of intrinsic model variability on the interpretation of sensitivity studies in a regional climate model (O'Brien et al.; 2010, Clim. Dyn.) and on the validation of a regional climate model with an updated boundary layer parameterization (O'Brien et al.; 2012, Geophys. Mod. Dev.). 

Model Development

The bulk of Travis' dissertation work involved coupling a new turbulence (boundary layer) parameterization into a regional climate model; he coupled the University of Washington turbulence parameterization into the International Centre for Theoretical Physics's regional climate model, RegCM4.1.    The new turbulence parameterization improves the representation of the physical processes that occur at the tops of stratiform clouds, and it allows RegCM4.1 to develop stratocumulus clouds and coastal fog.  This effort is described in O'Brien et al. (2012, Geophys. Mod. Dev.), Giorgi et al. (2012; Clim. Res.), and  O'Brien et al. (2012, Clim. Dyn.).

Travis currently serves as a volunteer developer on the RegCM development team, and he helps to maintain and develop the University of Washington code in RegCM.

Coastal Fog and California Climate: Model Application

Travis is using RegCM, Community Earth System Model, and various observational datasets to understand how and why California coastal fog has declined over the past century and how fog may change in the future.  So far this research has provided strong evidence that local sea surface temperatures are one of the strongest drivers of year-to-year variability in fog, and that systematic changes in near-coastal circulation (particularly a strengthening of subsidence related to a strengthening of the coastal jet) have driven the decline in fog.  Current efforts involve using a coupled ocean-atmosphere modeling system to understand how changes in near-coastal upwelling may additionally change coastal fog.


  • 2011-2013: Lawrence Berkeley National Lab
    Climate Science Postdoctoral Fellow.  Advisor: William D. Collins 
  • 2008-2011: University of California, Santa Cruz
    Ph. D. Earth Science. Dissertation: The Recent Past and Possible Future Decline of California Coastal Fog
    Advisors: Professor Lisa C. Sloan and Professor Patrick Y. Chuang
  • 2006-2008: University of California, Santa Cruz
    M. S. Earth Science. Thesis: How Did Airborne Dust Affect North American Climate During the 1930's Dust Bowl?
    Advisor: Professor Lisa C. Sloan
  • 2001-2005: University of California, Santa Cruz
    B. S. Physics. Thesis: Anisotropic Local Distortion of La1.2Sr1.8Mn2O7 Through the Ferromagnetic Transition Temperature
    Advisor: Professor Frank Bridges

Professional Experience

  • 2014-present: Research Scientist, Lawrence Berkeley National Lab
  • 2011-2013: Geological Postdoctoral Fellow, Lawrence Berkeley National Lab
  • 2010: Associate in Atmospheric Sciences, UC Davis
  • 2009-2011: Ph.D Candidate, UC Santa Cruz
  • 2006-2009: Graduate Student Researcher, UC Santa Cruz
  • 2006: Research Consultant, Los Alamos National Laboratory
  • 2004-2005: Research Assistant, UC Santa Cruz
  • 2004: Student Intern, Stanford Linear Accelerator

Selected Synergistic Activities

  • Invited participant in NSF-funded “Expert Witness Training Academy,” 2013 
  • Invited participant in interdisciplinary “Fog as a System” workshop, 2013 
  • Taught a “LaTeX for Science” course, LBNL Climate Department, 2013 
  • Weekly seminar co-organizer, LBNL Climate Department, 2012 
  • Session co-convener for AGU Fall Meetings:
    •  A033 (2013): Fog: Atmosphere, Biosphere, Ocean, and Land Interactions
    •  A025 (2012): Coastal Fog: Atmosphere, Biosphere, Ocean, and Land Interactions
    •  A066 (2012): Scale Dependence, Scale Invariance, and Scale Aware Parameterization
    •  GC15 (2010): Coastal Climates in a Changing World
    •  IN11D (2009): Management and Dissemination of Earth and Space Science Models 
  • Participant and Lab Instructor, ICTP RegCM Workshop and Tutorial, 2010 and 2012 
  • Associate (volunteer) developer, ICTP RegCM 
  • Participant, 2007 and 2008 Climate Leadership Summit, Santa Cruz, CA


Teaching Experience

  • Instructor, LaTeX for Science,  Lawrence Berkeley National Lab, Summer 2013
  • Teaching Assistant, Earth Sciences, 110B, Earth as a Chemical System, UCSC Winter 2011
  • Associate in Atmospheric Sciences, Atmospheric Sciences 120, Atmospheric Thermodynamics and Cloud Physics, UCD Fall 2010
  • Teaching Assistant, Earth Sciences 80C, Introduction to Weather and Climate, UCSC Fall 2009
  • Teaching Assistant Earth Sciences 110B, Earth as a Chemical System, UCSC Winter 2009
  • Teaching Assistant Earth Sciences 10, California Geology, UCSC Fall 2007
  • Teaching Assistant Earth Sciences 80D, Earth Sciences in the Cinema, UCSC Spring 2007

Current and Past Support

  • 01/14 - 12/14 PI, NERSC Initiative for Scientific Exploration, 20M CPU hours
     CASCADE: Calibrated And Systematic Characterization, Attribution, and Detection of Extremes
  • 10/13 - 10/16 CO-I, DOE Scientific Focus Area, $2.25M/year
    CASCADE: Calibrated And Systematic Characterization, Attribution, and Detection of Extremes
  • 09/08 - 09/10 PI, UCSC STEPS Institute, $1,000
    A New Model for the Future of Fog on California's Coast
  • 04/07 - 04/08 PI, UCSC STEPS Institute, $1,500
    A Neural Network Model of Agricultural Response to Local Climate
  • 03/07 PI, UCSC CDELSI Institute, $300
    Travel grant to present at AGU Joint Meeting, 2007