Infragravity Waves In The Deep Ocean: An Upward Revision

ISI Document Delivery No.: 244NQ Times Cited: 0 Cited Reference Count: 17 Cited References: Alsdorf D., 2007, EOS T AM GEOPHYS UN, V88, P253, DOI DOI 10.1029/2007EO240002 Arbic BK, 2010, OCEAN MODEL, V32, P175, DOI 10.1016/j.ocemod.2010.01.007 Ardhuin F, 2013, J FLUID MECH, V716, P316, DOI 10.1017/jfm.2012.548 Bromirski PD, 2010, GEOPHYS RES LETT, V37, DOI 10.1029/2009GL041488 de Laplace P. S., 1776, MAS, P542 de Jong MPC, 2003, J GEOPHYS RES-OCEANS, V108, DOI 10.1029/2002JC001422 Filloux J. H., 1991, P 20 GEN ASS IUGG VI FILLOUX JH, 1980, J PHYS OCEANOGR, V10, P1959, DOI 10.1175/1520-0485(1980)0102.0.CO;2 Harmon N, 2012, GEOPHYS RES LETT, V39, DOI 10.1029/2011GL050414 Henderson SM, 2002, J GEOPHYS RES-OCEANS, V107, DOI 10.1029/2000JC000498 Herbers S. Elgar, 1995, J PHYS OCEANOGR, V25, P1063 Herbers S. Elgar, 1994, J PHYS OCEANOGR, V24, P917 Le P. Y. L., 2008, J PHYS OCEANOGR, V38, P1137 LUTHER DS, 1990, GEOPHYS RES LETT, V17, P949, DOI 10.1029/GL017i007p00949 WEBB SC, 1991, J GEOPHYS RES-OCEANS, V96, P2723, DOI 10.1029/90JC02212 Webb SC, 2008, GEOPHYS J INT, V174, P542, DOI 10.1111/j.1365-246X.2008.03801.x Xu YS, 2011, J PHYS OCEANOGR, V41, P802, DOI 10.1175/2010JPO4558.1 Aucan, J. Ardhuin, F. ERC [240009]; U.S. National Ocean Partnership Program [N00014-10-1-0383]; Labex Mer [ANR-10-LABX-19-01]; French "Investissements d'avenir" through CNES; SWOT preparation program Bottom pressure data were provided by the U.S. National Ocean Data Center, V. Ballu (IPGP) and the Australian Bureau of Meteorology. F. A. is funded by ERC grant # 240009 "IOWAGA" with additional support from the U.S. National Ocean Partnership Program, under grant N00014-10-1-0383 and Labex Mer via grant ANR-10-LABX-19-01. This particular effort on infragravity waves is supported by the French "Investissements d'avenir" through CNES and the SWOT preparation program. This manuscript was partly written when author JA was hosted by Mark Merrifield and Douglas Luther at the University of Hawaii Sea Level Center. 0 AMER GEOPHYSICAL UNION WASHINGTON GEOPHYS RES LETTInternational audienceOcean infragravity waves are surface gravity waves with periods of several minutes and corresponding wavelengths of up to tens of kilometers. When propagating freely in the deep ocean, these waves are typically small, several centimeters at most, so they have been seldom studied. In the context of future wide-swath altimetry missions, these waves need to be better quantified as they have wavelengths that will be resolved by such instruments. Here, we analyze the global climatology and variability of infragravity waves in the deep ocean using data from over 40 open ocean locations, with depths larger than 2000 m. We show that typical infragravity wave heights are higher than previously estimated, with winter-averaged values up to 11 mm off the U. S. West Coast, and typically less than 6 mm in the tropics. The mid to high latitudes exhibit a strong seasonal cycle consistent with the local variability of the wind-waves, while the tropical Pacific has a higher energy level during the Austral winter that does not correlate well with the local wind-waves, suggesting a remote source for the recorded infragravity waves. These infragravity wave energies are expected to be a significant contribution to the error budget for possible measurements of sea level associated to sub-mesoscale currents at horizontal scales around 10 km. Hence, a global numerical model of infragravity waves will likely be necessary for the analysis of the planned Surface Water Ocean Topography mission