JONATHAN NASH

Jonathan D. Nash

Associate Professor, Physical Oceanography
College of Oceanic and Atmospheric Sciences
104 COAS Admin Bldg.
Oregon State University
Corvallis, OR, 97331
Office: 402 Burt Hall
Phone: (541) 737-4573; Fax: (541) 737-2064

email Jonathan; the address has been encrypted to avoid spambots

RESEARCH INTERESTS

PUBLICATIONS

OTHER LINKS

EDUCATION

Research Interests: Ocean Mixing

Exploring the physics of turbulence and mixing is key to our understanding of ocean dynamics. Innovative instrumentation, detailed analysis, and simple dynamical models enable us to:

understand the generation and evolution of turbulence
quantify irreversible fluxes of heat, salt, biology, chemicals and momentum
identify the processes (the pathways to turbulence) which produce these fluxes
determine the effects of turbulence on larger-scale flows.

Specific research projects include:

Physics of Ocean Mixing

Innovative instrumentation to explore dynamics down to the smallest scales of motion are crucial to understanding ocean turbulence and its effects. Some of the projects of the Ocean Mixing Group include:

the development of a fast-response thermocouple to measure temperature fluctuations at the smallest scales.
the analysis of highly resolved conductivity measurements to make the first direct estimates of turbulent salinity fluxes and salinity microstructure.
the observation of internal hydraulic flows (Stonewall Bank) on the continental shelf which produce intense mixing and high drag. (Link to 4MB PDF file)

RISE: River Influences on Shelf Ecosystems

RISE is a multidisciplinary effort to study physical and biogeochemical interactions in the complex Columbia River Plume ecosystem. Detailed observations reveal intense fronts, large-amplitude internal waves, shear-driven mixing, and intense bottom boundary layers. Visit the RISE website for more details.

TWIST: Turbulence and Waves over Irregularly Sloping Topography

Observations and modelling to better understand the interaction between internal waves and the corrugated continental slope off the east coast of the United States (with Eric Kunze). Visit the TWIST webpage for more details.

HOME: Hawaiian Ocean Mixing Experiment

The Absolute Velocity Profiler (AVP) and eXpendable Current Profilers (XCP) were used to characterize the internal waves radiating from the Hawaiian Ridge and estimate the associated dissipation (with Tom Sanford, Eric Kunze, and Craig Lee). More information can be found at the AVP HOME webpage.

Recent Publications:

Moum, J.N., J.M. Klymak, J.D. Nash, A. Perlin and W.D. Smyth (2007) Energy transport by nonlinear internal waves, J. Phys. Oceanogr., 37(7), 1968-1988, 2007

Jones, G. M., Nash, J. D., Doneker, R. L., and Jinka, G. H. (2007). Buoyant surface discharge into water bodies. I: Flow classification and prediction methodology., J. Hydraul. Eng., 133(9), 1010-1020

Martini, K. I., M. H. Alford, J. D. Nash, E Kunze, and M. A. Merrifield (2007), Diagnosing a partly standing internal wave in Mamala Bay, Oahu, Geophys. Res. Lett., 34, L17604, doi:10.1029/2007GL029749 (700 kB pdf).

Nash, J. D., M. H. Alford, E. Kunze, K. Martini, and S. Kelly (2007), Hotspots of deep ocean mixing on the Oregon continental slope, Geophys. Res. Lett., 34, L01605, doi:10.1029/2006GL028170 (900 kB pdf).

Nash, J.D. and J.N. Moum, 2005: River plumes as a source of large-amplitude internal waves in the coastal ocean, Nature 437, 400-403 (15 September 2005) | doi: 10.1038/nature03936, (500 kB pdf).

Nash, J.D., E. Kunze, C.M. Lee and T.B. Sanford, 2006: Structure of the baroclinic tide generated at Kaena Ridge, Hawaii, Journal of Physical Oceanography, 36(6), 1123-1135, (700 kB pdf).

Klymak, J.M., J.N. Moum, J.D. Nash, E. Kunze, T.B. Sanford and C.M. Lee, 2006: An Estimate of Tidal Energy Lost to Turbulence at the Hawaiian Ridge, Journal of Physical Oceanography,36(6), 1148-1164. (700 kB pdf)

Lee, C.M., E. Kunze, T.B. Sanford, J.D. Nash, M.A. Merrifield, and P.E. Holloway, 2006: Internal tides and turbulence along the 3000-m isobath of the Hawaiian Ridge, Journal of Physical Oceanography, 36(6), 1165-1183, (1.5 MB pdf).

Nash, J.D., M.H. Alford and E. Kunze, 2005: Estimating Internal Wave Energy Fluxes in the Ocean, Journal of Atmospheric and Oceanic Technology, 22(10) 1551--1570, (700KB pdf).

Nash, J.D., E. Kunze, J. M. Toole and R. W. Schmitt, 2004: Internal tide reflection and turbulent mixing on the continental slope, Journal of Physical Oceanography 34(5), 1117-1134 (2 MB pdf).

St. Laurent, L. C. and J. D. Nash, 2004: An examination of the radiative and dissipative properties of deep ocean internal tides, Deep Sea Research II, 51, 3029-3042 (500 KB pdf).

Doneker, R. L., J. D. Nash, and G. H. Jirka, 2004: Pollutant transport and mixing zone simulation of sediment density currents, J. Hydr. Engrg., 130(4), 349-359 (400 KB pdf).

D. L. Rudnick, T. J. Boyd, R. E. Brainard, G. S. Carter, G. D. Egbert, M. C. Gregg, P. E. Holloway, J. M. Klymak, E. Kunze, C. M. Lee, M. D. Levine, D. S. Luther, J. P. Martin, M. A. Merrifield, J. N. Moum, J. D. Nash, R. Pinkel, L. Rainville, T. B. Sanford, 2003: From tides to mixing along the Hawaiian Ridge, Science, 301(8), 355-357.

St. Laurent, L.C., and J.D. Nash, 2003: On the fraction of internal tide energy dissipated near topography, proceedings from the 13th 'Aha Huliko'a Hawaiian Winter Workshop.

Nash, J and J. Moum, 2002: Microstructure Estimates of Turbulent Salinity Flux and the Dissipation Spectrum of Salinity, Journal of Physical Oceanography, 32(8), 2312-2333 (1.6 MB pdf)

Moum, J., D. Caldwell, J. Nash and G. Gunderson, 2002: Observations of Boundary Mixing over the Continental Slope, Journal of Physical Oceanography, 32(7), 2113-2130. (3 MB pdf)

Nash, J. and J. Moum, 2001: Internal Hydraulic Flows on the Continental Shelf: High Drag States over a Small Bank, Journal of Geophysical Research, 106(C3), 4593-4612. (4 MB pdf)

Moum, J., and J Nash, 2000: Topographically-Induced Drag and Mixing at a Small Bank on the Continental Shelf, Journal of Physical Oceanography, 30(8), 2049-2054.

Nash, J., D Caldwell, M. Zelman, and J. Moum, 1999: A Thermocouple Probe for High-Speed Temperature Measurement in the Ocean, Journal of Atmospheric and Oceanic Technology, 16, 1474-1482. (230 KB PDF)

Nash, J. and J. Moum, 1999: Estimating Salinity Variance Dissipation Rate from Conductivity Microstructure Measurements, Journal of Atmospheric and Oceanic Technology, 16, 263-274. (330 KB PDF)

Nash, J. and G. Jirka, 1996: Buoyant Surface Discharges into Unsteady Ambient Flows: Dynamics of Atmospheres and Oceans. Volume 24, Number 1-4, pp. 75.

Nash, J. and G. Jirka, and D. Chen, 1995: Large Scale Planar Laser Induced Fluorescence in Turbulent Density-Stratified Flows: Experiments in fluids. Volume 19, Number 5, pp 297, 1995

Education:

B.Sc., Queen's University at Kingston, Ont. (Engineering Physics), 1991
M.Sc., Cornell University (Environmental Engineering), 1995
Ph.D., Oregon State University (Physical Oceanography), May 2000