STEVEN J COOPER portrait
  • Research Assistant Professor, Atmospheric Sciences
801-585-0095

Research Statement

My current research projects:

Impact of Snowfall Processes on Potential Vorticity Generation in High-Latitude Snow Events, PI, NSF.  The goal of this project is an improved understanding of the relationship between snowfall microphysical and dynamical processes for three meteorologically distinct high-latitude research sites in Alaska, Norway, and Sweden.  It exploits a synergistic in-situ measurement- remote sensing- numerical modeling approach using techniques previously developed by project personnel at U. Utah, U. Wisconsin, the Norwegian Meteorlogical Insititute, and the Swedish Meteoroloigcal and Hydrological Institute. The vertical profiles of precipitation properties for these sites will be quantified using retrieval schemes based upon advanced radar, passive microwave, and Fallgatter Technologies Multi-Angle Snowflake Camera (MASC) observations.  Observations of the vertical profile of precipitation properties will be comapred with their representation in numerical model simulations in WRF and HARMONIE for different synoptic conditions.  The MASC unit will be used to determine the environmental conditions under which different snow crystal types, e.g. aggregates vs. pristine shapes or rimed vs. non-rimed particles, may form.  Finally, retrieved profiles of precipitation properties will be used as a basis to quantify the impact of snowfall microphysical processes on potential vorticity (PV) generation through application of the  numerical weather prediction models.

Data product development for cold cloud and precipitation process analyses, Institutional PI, DOE ASR. This project focused on the creation of an operational snow product for the instrumentation of the ARM North Slope Alaska (NSA) atmospheric observatory facilities at Barrow and Oliktok Point.  Specifically, we created an optimal-estimation snowfall retrieval algorithm based upon 35 GHZ Ka-band Zenith Radar (KAZR) reflectivity and Doppler fallspeed observations at each site.    This retrieval scheme represented a modification of the W-band CloudSat 2C-SNOW-PROFILE scheme to ASR ground instrumentation.  However, the scheme also sought to include surface-based measurements of snowflake microphysical properties such as fallspeed and particle size distributions, when possible, to refine the estimate of snowfall from the KAZR observations.   

 

 

 

My past research projects:

My Ph.D. work at Colorado State Unviersity consisted of the development of an optimal-estimation multiple- sensor ice cloud retrieval scheme for the instrumentation of the NASA Afternoon A-Train constellation of satellites.  This work included the development of an operational retrieval as well as a  theoretical information content analysis exploring our ability to characterize these clouds given current observational platforms.

 

Other research projects were more practical in nature and included such varies topics as the measurement of ice cloud properties from ground- based radiometers, use of infrared remote sensing to constrain in-situ estimates of ice cloud particle size,  and the monitoring of atmospheric conditions at South Pole Station, Antarctica.

 

 

 

 
 

 

 

Research Keywords

  • Atmospheric Remote Sensing
  • Snow science
  • Precipitation
  • Weather Analysis and Forecasting

Presentations

  • Characterization of snowfall properties at high-latitude sites through use of a combined Multi-Angle Snow Camera (MASC) and radar approach @ AGU 2016. Invited Talk/Keynote, Presented, 12/14/2016.
  • 2015 Use of Multi-Angle Snow Camera (MASC) Observations as a Constraint on Radar-Based Estimates of Snowfall @ University of Oslo, Norway. Invited Talk/Keynote, Presented, 10/27/2015.
  • 2015 Use of Multi-Angle Snow Camera (MASC) Observations as a Constraint on Radar-Based Estimates of Snowfall @ Swedish Meteorological and Hydrological Institute (SMHI). Invited Talk/Keynote, Presented, 10/20/2015.
  • The impact of observed ice particle size distributions and shape on multiple-sensor cloud and precipitation retrieval schemes . Poster, Presented, 11/03/2014.
  • Impact of Uncertainties in Cloud and Precipitation Microphysical Properties on Climate Studies @ Gothenburg University. Invited Talk/Keynote, Presented, 08/21/2014.
  • Towards improved estimates of snowfall and ice cloud properties from radar and Multi-Angular Snowflake Camera (MASC) observations @ Norwegian Meteorological Institute. Invited Talk/Keynote, Presented, 08/13/2014.
  • On the Limitations of Satellite Passive Measurements for Climate Process Studies @ Lulea Technological Institute. Invited Talk/Keynote, Presented, 08/13/2013.
  • On the need for improved satellite observations for cloud and precipitation climate process studies @ Chalmers University Environmental Series Lecture. Invited Talk/Keynote, Presented, 07/2012.
  • Towards a combined lidar, radar, and passive radiance retrieval scheme for the instrumentation of the A-Train satellites. Poster, Presented, 11/2010.
  • Identification of Small Ice Cloud Particles Using Passive Radiometric Observations. Conference Paper, Presented, 07/2010.

Grants, Contracts & Research Gifts

  • Collaborative Research: Impact of Snowfall Processes on Potential Vorticity Generation in High-Latitude Snow Events. PI: Steven Cooper. NSF, 07/01/2015 - 06/30/2018. Total project budget to date: $449,000.00
  • Impacts of distant pollution sources on microphysical transitions in Arctic clouds. PI: Timothy Garrett. Co-PI(s): Steven Cooper. NSF, 08/01/2013 - 07/31/2016. Total project budget to date: $451,000.00

Geographical Regions of Interest

  • Antarctica
  • Northern America
    Alaska- Arctic.
  • Norway
  • Sweden

Research Equipment and Testing Expertise

  • Multi-Angle Snow Camera.

Publications

  • Mace, Gerald., S. Avey, SJ Cooper, M. Lebsock, S. Tanelli, G. Dobrowlski, ‘Co-Occurring Cloud and Precipitation Properties of Warm Marine Boundary Layer Clouds with A-Train Data’, accepted J. Geophy. res. Accepted, 08/2015.
  • Lebsock M. and Cooper S.: Cloud Properties. In: Njoku E. (Ed.) Encyclopedia of Remote Sensing: Springer Reference. Springer-Verlag Berlin Heidelberg, 2013. Published, 01/2013.
  • Cooper, Steven J and Timothy Garrett, ‘Application of infrared remote sensing to constrain in-situ estimates of ice crystal particle size during SPartICus’, Atmos. Meas. Tech., 4, 1593-1602, doi:10.5194/amt-4-1593-2011, 2011. Published, 08/2011.
  • Cooper, Steven J., Timothy J. Garrett, Identification of Small Ice Cloud Particles Using Passive Radiometric Observations. J. Appl. Meteor. Climatol., 49, 2334–2347. doi: 10.1175/2010JAMC2466.1, 2010. Published, 11/2010.
  • Cooper, Steven J., Tristan S. L’Ecuyer, Philip Gabriel, Anthony Baran, and Graeme L. Stephens, “Performance assessment of a five-channel estimation- based ice cloud retrieval scheme for use over the global ocean”, Journal of Geophysical Research, 2006JD007122, 2007. Published, 02/2007.
  • Cooper, Steven J., Tristan S. L’Ecuyer, Philip Gabriel, Anthony Baran, and Graeme L. Stephens, “Objective Assessment of the Information Content of Visible and Infrared Radiance Measurements for Cloud Microphysical Property Retrievals over the Global Oceans. Part II: Ice Clouds, Journal of Applied Meteorology and Climatology, vol. 45, Issue 1, p.42-62, 2006. Published, 01/2006.
  • L’Ecuyer, Tristan S., Philip Gabriel, Kyle Leesman, Steven J. Cooper, and Graeme L. Stephens, “Objective Assessment of the Information Content of Visible and Infrared Radiance Measurements for Cloud Microphysical Property Retrievals over the Global Oceans. Part I: Water Clouds, Journal of Applied Meteorology and Climatology, vol. 45, Issue 1, p.20-41, 2006. Published, 01/2006.
  • Cooper, Steven J., Tristan S. L’Ecuyer, and Graeme L. Stephens, “The Impact of Explicit Cloud Boundary Information on Ice Cloud Microphysical Property Retrievals from Infrared Radiances”, Journal of Geophysical Research, 108(D3), 4107, doi:10.1029/2002JD002611, 2003. Published, 06/2003.
  • Thornburg, Jonathan, Steven J. Cooper and David Leith, “Counting Efficiency of the API Aerosizer”, Journal of Aerosol Science, 30(4): 479-488 , 1999. Published, 04/1999.
  • Cooper, Steven J. and David Leith, “Evaporation of Metalworking Fluid Mist in Laboratory and Industrial Collectors”, American Industrial Hygiene Association Journal, v. 59, p. 45-51, 1998. Published, 06/1998.
  • Raynor, Peter C., Steven J. Cooper, and David Leith, “Evaporation of Polydisperse Multicomponent Droplets”, American Industrial Hygiene Association Journal, v. 57, p. 1128- 1136, 1996. Published, 12/1996.
  • Cooper, Steven J., Peter C. Raynor and David Leith, “Evaporation of Mineral Oil in a Mist Collector”, Applied Occupational and Environmental Hygiene, v 11, p. 1204-1211, 1996. Published, 10/1996.
  • Leith, David, Peter C. Raynor, Maryanne G. Boundy, and Steven J. Cooper, "Performance of Industrial Equipment to Collect Coolant Mist", American Industrial Hygiene Association Journal, 57: 1142-1148 (1996). Published, 06/1996.