Feature Publication Archive
Matsumoto, H., D.R. Bohnenstiehl, J. Tournadre, R.P. Dziak, J.H. Haxel, T.-K.A. Lau, M. Fowler, and S.A. Salo (2014): Antarctic icebergs: A significant natural sound source in the Pacific Ocean. Geochem. Geophys. Geosyst., 15, doi: 10.1002/2014GC005454.
Previous research indicates that low-frequency ocean noise levels have risen 3 to 4 times since the early 1960s in some areas. This rise has been largely attributed to increased global ship traffic. The scientific community has become increasingly concerned about the adverse effects of anthropogenic (human-made) inputs to the marine ecosystem, and in particular to marine animals, which rely on sound to aid in migration, feeding, and breeding.
PMEL’s Acoustics Program has been monitoring the low-frequency acoustic... more »
Toomey, D.R., R.M. Allen, A.H. Barclay, S.W. Bell, P.D. Bromirski, R.L. Carlson, X. Chen, J.A . Collins, R.P. Dziak, B. Evers, D.W. Forsyth, P. Gerstoft, E.E.E. Hooft, D. Livelybrooks, J.A . Lodewyk, D.S. Luther, J.J. McGuire, S.Y. Schwartz, M. Tolstoy, A.M. Tréhu, M. Weirathmueller, and W.S.D. Wilcock (2014): The Cascadia Initiative: A sea change in seismological studies of subduction zones. Oceanography, 27(2), doi:10.5670/oceanog.2014.49, 138-150.
There is increasing scientific and public awareness that the Cascadia subduction zone, an active plate boundary fault off the coast of the Pacific Northwest (PNW), is capable of generating great earthquakes (magnitude 9 or larger). Concern over the earthquake hazard of this zone motivated creation of the Cascadia Initiative, an NSF sponsored community project to deploy and maintain an array of onshore/offshore seismic and geodetic sensors. PMEL scientists are co-investigators on the project and have led four oceanographic expeditions to collect data from the seafloor seismic components of... more »
Chen, K., L. Ciannelli, M.B. Decker, C. Ladd, W. Cheng, Z. Zhou, and K.-S. Chan (2014): Reconstructing source-sink dynamics in a population with a pelagic dispersal phase. PLoS ONE, 9(5), e95316, doi: 10.1371/journal.pone.0095316.
Many marine species have a larval phase. In this phase, larvae drifts with the prevailing ocean currents before settling in nursery locations. In such cases, the spawning locations can be represented as sources and the settling locations of the juvenile or adult stages as sinks. Population connectivity and directionality of flow between sources and sinks can have important implications for management and conservation. The reconstruction of source-sink dynamics is often hampered by limited knowledge of the spatial distribution of either the source or sink components or lack of information... more »
Long, M.S., W.C. Keene, D.J. Kieber, A.A. Frossard, L.M. Russell, J.R. Maben, J.D. Kinsey, P.K. Quinn, and T.S. Bates (2014): Light-enhanced primary marine aerosol production from biologically productive seawater. Geophys. Res. Lett., 41(7), doi: 10.1002/2014GL059436, 2661–2670.
Breaking waves on the ocean surface produce bubbles that burst at the air-sea interface and inject sea spray aerosol (SSA) into the atmosphere ranging in size from 0.01 to 20 micrometers. This process is the dominant source of aerosol particle mass and a major source of aerosol particle number to the Earth's atmosphere. The resulting SSA has significant impacts on atmospheric chemistry and physics. SSA production and properties are influenced by organic matter in seawater that adsorbs to the surfaces of freshly produced bubbles, forming organic films on the emitted SSA. Although research... more »
Lyman, J., and G.C. Johnson (2014): Estimating global ocean heat content changes in the upper 1800 m since 1950 and the influence of climatology choice. J. Climate, 27, doi: 10.1175/JCLI-D-12-00752.1, 1946-1958.
With the buildup of greenhouse gasses in the atmosphere, more energy enters the top of the atmosphere than escapes. About 93% of this energy imbalance has warmed the ocean, with about 3% warming the land, 3% melting ice, and 1% warming and adding moisture to the atmosphere. Warmed oceans also expand, raising sea level. Hence, understanding how much energy is being stored by the oceans and where is important to understanding how much and how fast the Earth will warm and sea level will rise.
Over the last six decades, ocean temperature has been measured over increasing areas of the... more »