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Andy Jessup

Chair, AIRS Department & Senior Principal Oceanographer

Professor, Civil and Environmental Engineering and Affiliate Associate Professor, Mechanical Engineering





Research Interests

Air-Sea Interaction, Remote Sensing


Dr. Jessup joined APL-UW as a research scientist in 1990 after receiving his Ph.D. in Oceanography and Ocean Engineering from the MIT/WHOI Joint Program. He began a program in air-sea interaction using infrared techniques that has led to a wide variety of field and laboratory investigations.

His recent interests include remote sensing of river inlets and the infrared signature of breaking waves relevant to wake detection. He is Chair of the Air-Sea Interaction and Remote Sensing Department and a Professor in Civil and Environmental Engineering.


B.S.E. Engineering Science, University of Michigan, 1980

M.S.E. Civil Engineering, Massachusetts Institute of Technology, 1988

Ph.D. Oceanography & Ocean Engineering, MIT and WHOI Joint Program, 1990


Salinity Processes in the Upper Ocean Regional Study — SPURS

The NASA SPURS research effort is actively addressing the essential role of the ocean in the global water cycle by measuring salinity and accumulating other data to improve our basic understanding of the ocean's water cycle and its ties to climate.

15 Apr 2015

Skin and Bulk Sea Surface Temperature Validation Program

There is a growing consensus that sea surface temperature (SST) products derived from satellite-based infrared (IR) sensors should include ocean skin temperature. To validate satellite-based measurements of skin temperature, widespread, in situ data are required.


Fluxes, Air-Sea Interaction, and Remote Sensing (FAIRS) Experiment

The transfer of momentum, heat, and gas across the air-sea boundary is characterized and quantified by measuring the underlying physical mechanisms with remote sensing instruments.


More Projects


2000-present and while at APL-UW

Small boat detection with along-track interferometric SAR

Balaban, M., A. Kovorotniy, Y. Goncharenko, V. Gorobets, F. Kivva, G. Farquharson, and A. Jessup, "Small boat detection with along-track interferometric SAR," IEEE Radar Conference, 8-12 May, Seattle, WA, doi:10.1109/RADAR.2017.7944356 (IEEE, 2017).

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8 May 2017

Along-track interferometric synthetic aperture radar measurements of a small fiberglass-hull boat were made in various wind and wave conditions and for different measurement geometries and boat speeds. The data collected show three different cases: 1) the boat signature is visible both in the backscattered power and interferometric phase images; 2) the boat signature is visible only in the interferometric phase image, and 3) the boat signature is not visible in either image. From a preliminary analysis of the data, we conclude that the angle between radar look direction and the nominal velocity vector of the boat significantly affects boat detection. The worst cases for detection are when those vectors are collinear or oppositely directed. The best detection cases appear to be for the case, when boat velocity vector and radar look direction are orthogonal or when the boat is stationary.

Remote measurements of tides and river slope using an airborne Lidar instrument

Hudson, A.S., S.A. Talke, R. Branch, C. Chickadel, G. Farquharson, and A. Jessup, "Remote measurements of tides and river slope using an airborne Lidar instrument," J. Atmos.Ocean.Technol., 34, 897–904, doi:10.1175/JTECH-D-16-0197.1, 2017.

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24 Apr 2017

Tides and river slope are fundamental characteristics of estuaries, but they are usually undersampled due to deficiencies in the spatial coverage of water level measurements. This study aims to address this issue by investigating the use of airborne lidar measurements to study tidal statistics and river slope in the Columbia River estuary. Eight plane transects over a 12-h period yield at least eight independent measurements of water level at 2.5-km increments over a 65-km stretch of the estuary. These data are fit to a sinusoidal curve and the results are compared to seven in situ gauges. In situ– and lidar-based tide curves agree to within a root-mean-square error of 0.21 m, and the lidar-based river slope estimate of 1.8 × 10−5 agrees well with the in situ–based estimate of 1.4 × 10−5 (4 mm km−1 difference). Lidar-based amplitude and phase estimates are within 10% and 8°, respectively, of their in situ counterparts throughout most of the estuary. Error analysis suggests that increased measurement accuracy and more transects are required to reduce the errors in estimates of tidal amplitude and phase. However, the results validate the use of airborne remote sensing to measure tides and suggest this approach can be used to systematically study water levels at a spatial density not possible with in situ gauges.

Infrared emissivity of seawater and foam at large incidence angles in the 3–14 μm wavelength range

Branch, R., C.C. Chickadel, and A.T. Jessup, "Infrared emissivity of seawater and foam at large incidence angles in the 3–14 μm wavelength range," Remote Sens. Environ., 184, 15-24, doi:10.1016/j.rse.2016.06.009, 2016.

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1 Oct 2016


We measured infrared emissivity of seawater and sea foam in a laboratory experiment.

We developed a method to estimate emissivity for incidence angles up to 85°.

Foam emissivity is higher than water for all wavelengths and angles > 65°.

The difference between foam and water emissivity increases with incidence angle.

More Publications


Lighter-than-Air Visible and Infrared Imaging SYstem for Persistent Surveillance

Record of Invention Number: 8283D

Andy Jessup, Dan Clark


4 Feb 2009

Acoustics Air-Sea Interaction & Remote Sensing Center for Environmental & Information Systems Center for Industrial & Medical Ultrasound Electronic & Photonic Systems Ocean Engineering Ocean Physics Polar Science Center