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Rod Frehlich

Rod G. Frehlich

Education

Doctor of Philosophy, 1982, University of California, San Diego.

Masters of Science, 1977, University of Saskatchewan, Saskatoon.

Bachelor of Science, 1974, University of Saskatchewan, Saskatoon.

Employment History

1998-Present: Scientific visitor at the National Center for Atmospheric Research supporting the Research Applications Program (RAP) to detect severe turbulence for commercial aircraft and airports using Doppler radar and lidar, forecasting turbulence with numerical weather prediction model output, measurements of turbulence for stable boundary layer studies, effects of turbulence on measurement accuracy, and optimal data assimilation techniques based on local estimates of total observation error statistics.

1985-Present: Senior Research Scientist for CIRES at University of Colorado , Boulder . Areas of research are atmospheric turbulent processes, optimal data assimilation, effects of turbulence on current and future measurement systems, and verification of measurement systems. Recent research projects include evaluation of lidar systems for measurements of winds from ground-based and space-based platforms, turbulence measurements from kite-platforms, evaluation of Doppler radar and lidar parameter estimation algorithms, measurements of wind-field statistics using Doppler lidar, verification of Doppler lidar performance, and optimal data assimilation algorithms.

1984: Research Scientist at the La Jolla Institute. Studied theoretical techniques for wave propagation in random media. Investigated the equivalence of path integral and moment equation methods. Developed a simulation package to study wave propagation in random media.

1983: Project Manager in charge of the design and construction of a steerable radio telescope. Involved in all aspects of phased array design and construction.

1982: Visiting Lecturer at UCSD. Taught upper division Electronics Lab and a course on wave theory and transmission lines.

1977-82: Doctoral research on laser propagation in the atmosphere. GPA-4.0. Performed simultaneous measurements of the angular spectrum and intensity correlation. Developed an analytic expansion for the intensity spectrum for the thin screen problem that includes the inner scale of turbulence. Developed an analog computer to simulate a non-linear stochastic system.

1974-77: Studied the statistical structure of auroral processes. Developed a non-stationary stochastic model that permitted more accurate determination of auroral parameters. The validity of the procedure was tested by a simulation. GPA-4.0.

Selected Publications in Refereed Journals

Frehlich, R. G., and R. Sharman, "Estimates of turbulence from numerical weather prediction model output with applications to turbulence diagnosis and data assimilation," Monthly Weather Review, Vol. 132, pg. 2308-2324,(2004).

Frehlich, R. G., Y. Meillier, M. L. Jensen, B. Balsley, "Statistical description of small scale turbulence in the lowlevel nocturnal jet", J. Atmos. Sci., Vol. 61, 1079-1085, (2004).

Frehlich, R. G., Y. Meillier, M. L. Jensen, Ben Balsley, "Turbulence measurements with the CIRES tethered lifting system during CASES-99: calibration and spectral analysis of temperature and velocity," J. Atmos. Sci., Vol. 60, 2487-2495, (2003).

Balsley, B.B., M. L. Jensen, R. G. Frehlich, Y. Meillier, and A. Muschinski, "Structure and evolution of mean and turbulence characteristics of the nighttime lower troposphere above Kansas in the presence of a low-level jet," J. Atmos. Sci., Vol. 60, 2496-2508, (2003).

Frehlich, R. G., and L. Cornman, "Estimating spatial velocity statistics with coherent Doppler lidar", J. Atmos. Ocean. Tech., Vol. 19, 355-366, (2002).

Frehlich, R. G., "Errors for space-based Doppler lidar wind measurements: Definition, performance, and verification", J. Atmos. Oceanic Tech., Vol. 18, 1749-1772, (2001).

Frehlich, R. G., "Estimation of velocity error for Doppler lidar measurements", J. Atmos. Ocean . Tech., Vol. 18, 1628-1639, (2001).

Frehlich, Rod "Simulation of coherent Doppler lidar performance for space-based platforms", J. Appl. Meteor., Vol. 39, 245-262, (2000).

Frehlich, Rod and Larry Cornman, "Coherent Doppler lidar signal spectrum with wind turbulence", Appl. Opt., Vol. 38, 7456-7466, (1999).

Frehlich, R. G., "Maximum likelihood estimators for Doppler radar and lidar," J. Atmos. Ocean . Tech., Vol. 16,1702-1709, (1999).

Balsley, B. B., M. L. Jensen, and R. G. Frehlich, "The use of state-of-the-art kites for profiling the lower atmosphere", Boundary-Layer Meteorology, Vol. 87, 1-25, (1998).

Frehlich, R. G., Stephen Hannon, and Sammy Henderson, "Coherent Doppler lidar measurements of wind field statistics", Boundary-Layer Meteorology, Vol. 86, 233-256, (1998).

Strauch, R. G., and R. Frehlich, "Doppler weather radar velocity measurements using a single pulse", J. Atmos. Ocean. Tech., Vol. 15, 804-808, (1998).

Frehlich, R. G., Stephen Hannon, and Sammy Henderson, "Coherent Doppler lidar measurements of winds in the weak signal regime," Appl. Opt., 36, 3491-3499, (1997).

Frehlich, Rod, "Effects of wind turbulence on coherent Doppler lidar performance," J. Atmos. Ocean. Tech., 14, 54-75, (1997).

Frehlich, R. G., "Simulation of coherent Doppler lidar performance in the weak signal regime," J. Atmos. Ocean. Tech., 13, 646-658, (1996).

Frehlich, Rod , "Comparison of 2 and 10 micron coherent Doppler lidar performance," J. Atmos. Ocean. Tech., 12, 415-420, (1995).

Frehlich, R. G., and M. J. Yadlowsky, "Performance of mean-frequency estimators for Doppler radar and lidar," J. Atmos. Ocean. Tech., 11, 1217-1230, (1994).

Frehlich, R. G., "Coherent Doppler lidar signal covariance including wind shear and wind turbulence," Appl. Opt.33, 6472-6481, (1994).

Frehlich, Rod, Stephen Hannon, and Sammy Henderson, "Performance of a 2 m m coherent Doppler lidar for wind measurements," J. Atmos. Ocean. Tech., 11, 1517-1528, (1994).

Frehlich, Rod, "Cramer Rao Bounds for Gaussian random processes and applications to radar processing of atmospheric signals," IEEE Trans. Geoscience and Remote Sensing, 31, 1123-1131, (1993).

Frehlich, Rod, "Laser scintillation measurements of the temperature spectrum in the atmospheric surface layer," J. Atmos. Sci., 49, 1494-1509, (1992).

Frehlich, Rod G., and Michael J. Kavaya, "Coherent laser radar performance for general atmospheric refractive turbulence," Appl. Opt., 30, 5325-5352, (1991).

Kavaya, Michael J., Sammy W. Henderson, Edward C. Russell, R. Milton Huffaker, and Rod G. Frehlich, "Monte Carlo computer simulations of ground-based and space-based coherent dial water vapor profiling," Appl. Opt., 28, 840-850, (1989).