Ocean Observing

The processes that occur along coastal margins are strongly affected by, and to a large extent dependent on, forcing from episodic events such as freshwater runoff, storm winds, seasonal tides and surface and internal waves. Coastal ocean observatories enable real-time, long-term monitoring of these intermittent events and of the associated environmental response. Cabled systems further ease constraints on communications and power, opening the door to new instrumentation, adaptive sampling and manipulative experimentation. The Kilo Nalu Observatory (KNO) was established by Professor Pawlak while at Department of Ocean and Resources Engineering at the University of Hawaii with the aim of providing this sort of access to the tropical reef environment.

The broad goals for KNO have been to provide support for coastal ocean and tropical reef research, stimulate ocean technology development, obtain long-term time-series observations for validation of ocean prediction models and to enable ocean education and outreach opportunities. The KNO infrastructure has provided baseline observations on the coastal ocean environment along with data and power connections at guest ports for user-specific experiment modules.

The observatory, whose name combines the Hawaiian words kilo meaning “to observe” and nalu meaning “ocean waves”, builds on a series of earlier cabled ocean observing efforts undertaken in and around Hawai’i, including HUGO and more recently the ALOHA cabled observatory. Kilo Nalu was initiated with funding from the US Office of Naval Research in support of a study on wave and current physics over coral reefs. The first generation of the observatory backbone was based on the electronics design of the Monterrey In Situ Observatory (MISO: www.oc.nps.edu/ ~stanton/miso/). The second generation KN backbone was developed and deployed as part of a National Science Foundation Coastal Oceans Processes (CoOP) project targeting benthic biogeochemistry and physics. Kilo Nalu now forms a core component of the broader Hawai’i Ocean Observing System (HIOOS: www.hioos.org).

Between 2004 and 2012 KNO data has been instrumental in developing understanding of a range of processes for tropical island shelves including porewater exchange processes, thin layer formation, wave/current boundary layer processes, plume dispersion, cross-shore exchange and shoaling internal waves. In addition to focused efforts, the time-series data at Kilo Nalu has also yielded important research. Analysis of observations in November 2006 of a small tsunami that impacted Oahu identified tsunami-generated coastal trapped waves as an important mechanism in generating high-frequency motions and surface displacements (Bricker et al., 2007). Analysis of subsequent tsunami events including the 2012 Tohoku tsunami has yielded important data for computer models of tsunamis (Yamazaki et al, 2012)

The NSF CoOP-funded work also includes a significant educational outreach program under development in collaboration with Bishop Museum (www.bishopmuseum. org), a leader in local science and cultural outreach. The program aims to make the research accessible to the local community and to exploit the real-time access to ocean data for educational purposes.

Publications

A.B. Hebert, F. J. Sansone, G. Pawlak, "Tracer dispersal in sandy sediment porewater under enhanced physical forcing", Continental Shelf Research, 27, no. 17, p. 2278-2287, doi:10.1016/j.csr.2007.05.016, Oct. 2007

J.D. Bricker, S. Munger, C. Pequignet, J.R. Wells, G. Pawlak, K. F. Cheung, "ADCP observations of edge waves off Oahu in the wake of the November 2006 Kuril Islands tsunami",, Geophys. Res. Lett., 34, L23617, doi:10.1029/2007GL032015, Dec. 2007

V. Nunes and G. Pawlak, “Observations of Physical Roughness Over a Coral Reef”, Journal of Coastal Research, 24, 2B, 2008

N.L Jones, R.J. Lowe, G. Pawlak, D.A. Fong, S.G. Monismith, "Plume dispersion on a fringing coral reef system", Limnology and Oceanography, 53, no.5 pt. 2, pp 2273-2286, 2008

F.J. Sansone, G. Pawlak, T.P. Stanton, M.A. McManus, B.T. Glazer, E.H. DeCarlo, M. Bandet, J. Sevadjian, K. Stierhoff, C. Colgrove, A.B. Hebert, and I.C. Chen, "Kilo Nalu: Physical/Biogeochemical Dynamics Above and Within Permeable Sediments", Oceanography, 21, no. 4, Dec. 2008

G. Pawlak, E. De Carlo, J. Fram, A. Hebert, C. Jones, B. McLaughlin, M. McManus, K. Millikan, F. Sansone, T. Stanton & J. Wells, "Development, Deployment, and Operation of Kilo Nalu Nearshore Cabled Observatory", IEEE OCEANS 2009 Conference, Bremen, 2009

J. Sevadjian, M.A.McManus, G. Pawlak, “Effects of physical structure and processes on thin zooplankton layers in Mamala Bay, Hawai’i.”, Marine Ecology Progress Series, 409: 95-106, 2010.

S. Jaramillo and G. Pawlak, “AUV-based observations of rough bed hydrodynamics”, Proceedings IEEE AUV2010 Conference, Monterey, September 2010

L. Tuthill, J.R. Wells*, G. Pawlak, S. Monismith, “Dynamics of cross-shore thermal exchange on a tropical fore-reef”, Seventh International Symposium on Stratified Flows, Rome, Italy, August, 2011.

S. Jaramillo and G. Pawlak, “Coral reef hydrodynamics: AUV-based bed-roughness mapping over a tropical reef”, Coral Reefs, in press, 2011.

M. S. Tomlinson, E. H. De Carlo, M. A. McManus, G. Pawlak, G. F. Steward, F. J. Sansone, O. D. Nigro, C. E. Ostrander, R.E. Timmerman, J. Patterson, S. Jaramillo*, “Monitoring the Effects of Storms on Coastal Water Quality with the Hawai‘i Ocean Observing System (HiOOS)”, Oceanography, 2011.

G. Pawlak, M.McManus, L. Tuthill, J. Sevadjian, M. Ericksen, A. Rocheleau, “Real-time ocean water quality monitoring for the south shore of Oahu”, MTS/IEEE OCEANS ‘11, Kona, Hawaii, Sept. 2011.

J. Gebbie, M. Siderius, J. S. Allen, “Passive acoustic array harbor security applications”, Mar. Tech. Soc. J., 45, no. 3, 2011.

Arcas, D, and Y Wei: Evaluation of velocity-related approximations in the non-linear shallow water equations for the Kuril Islands, 2006 tsunami event at Honolulu, Hawaii. Geophys. Res. Lett., 2011

J.R. Wells, J. P. Fram and G. Pawlak, “Solar warming of the seafloor on a fringing reef”, J. Marine Research, 70, 4, 641-660, 2012.

Y. Yamazaki, K.F. Cheung, G. Pawlak, T. Lay, “Surges along the Honolulu Coast from the 2011 Tohoku Tsunami”, Geophysical Research Letters, 39, 9, doi:10.1029/2012GL051624, 2012.