ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Coral reef  (2)
  • California Current System  (1)
  • American Geophysical Union  (3)
  • American Geophysical Union (AGU)
Collection
Publisher
Years
  • 1
    Publication Date: 2022-05-25
    Description: Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 117 (2012): C02008, doi:10.1029/2011JC007589.
    Description: Upper ocean thermohaline structure in the California Current System is investigated using sustained observations from autonomous underwater gliders and a numerical state estimate. Both observations and the state estimate show layers distinguished by the temperature and salinity variability along isopycnals (i.e., spice variance). Mesoscale and submesoscale spice variance is largest in the remnant mixed layer, decreases to a minimum below the pycnocline near 26.3 kg m−3, and then increases again near 26.6 kg m−3. Layers of high (low) meso- and submesoscale spice variance are found on isopycnals where large-scale spice gradients are large (small), consistent with stirring of large-scale gradients to produce smaller scale thermohaline structure. Passive tracer adjoint calculations in the state estimate are used to investigate possible mechanisms for the formation of the layers of spice variance. Layers of high spice variance are found to have distinct origins and to be associated with named water masses; high spice variance water in the remnant mixed layer has northerly origin and is identified as Pacific Subarctic water, while the water in the deeper high spice variance layer has southerly origin and is identified as Equatorial Pacific water. The layer of low spice variance near 26.3 kg m−3 lies between the named water masses and does not have a clear origin. Both effective horizontal diffusivity, κh, and effective diapycnal diffusivity, κv, are elevated relative to the diffusion coefficients set in the numerical simulation, but changes in κh and κv with depth are not sufficient to explain the observed layering of thermohaline structure.
    Description: We gratefully acknowledge funding from the Gordon and Betty Moore Foundation, the Coastal Ocean Currents Monitoring Project (COCMP), and NOAA. R. E. Todd was partially supported by the Postdoctoral Scholar Program at the Woods Hole Oceanographic Institution, with funding provided by the Cooperative Institute for the North Atlantic Region.
    Description: 2012-08-03
    Keywords: California Current System ; Adjoint model ; Glider ; Passive tracer ; Spice ; Thermohaline structure
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2022-10-26
    Description: Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 125(5), (2020): e2019JC015377, doi:10.1029/2019JC015377.
    Description: Internal waves strongly influence the physical and chemical environment of coastal ecosystems worldwide. We report novel observations from a distributed temperature sensing (DTS) system that tracked the transformation of internal waves from the shelf break to the surf zone over a narrow shelf slope region in the South China Sea. The spatially continuous view of temperature fields provides a perspective of physical processes commonly available only in laboratory settings or numerical models, including internal wave reflection off a natural slope, shoreward transport of dense fluid within trapped cores, and observations of internal rundown (near‐bed, offshore‐directed jets of water preceding a breaking internal wave). Analysis shows that the fate of internal waves on this shelf—whether transmitted into shallow waters or reflected back offshore—is mediated by local water column density structure and background currents set by the previous shoaling internal waves, highlighting the importance of wave‐wave interactions in nearshore internal wave dynamics.
    Description: We are grateful for the support of the Dongsha Atoll Research Station (DARS) and the Dongsha Atoll Marine National Park, whose efforts made this research possible. The authors would also like to thank A. Hall, S. Tyler, and J. Selker from the Center for Transformative Environmental Monitoring Programs (CTEMPs) funded by the National Science Foundation (EAR awards 1440596 and 1440506), G. Lohmann from WHOI, A. Safaie from UC Irvine, G. Wong, L. Hou, F. Shiah, and K. Lee from Academia Sinica for providing logistical and field support, as well as E. Pawlak, S. Lentz, B. Sanders, and S. Grant for equipment, and B. Raubenheimer, S. Elgar, R. Walter and D. Lucas for informative discussions that improved this work. We acknowledge the US Army Research Laboratory DoD Supercomputing Resource Center for computer time on Excalibur, which was used for the numerical simulations in this work. Funding for this work supported by Academia Sinica and for K.D. and E.R. from NSF‐OCE 1753317 and for O.F., J.R., and R.A. from ONR Grant 1182789‐1‐TDZZM. A portion of this work (R.A.) was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE‐AC52‐07NA27344.
    Description: 2020-10-21
    Keywords: Internal waves ; Distributed temperature sensing ; Coral reef ; Internal wave reflection
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2022-10-26
    Description: Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 125(12), (2020): e2020JC016543, https://doi.org/10.1029/2020JC016543.
    Description: On coral reefs, flow determines residence time of water influencing physical and chemical environments and creating observable microclimates within the reef structure. Understanding the physical mechanisms driving environmental variability on shallow reefs, which distinguishes them from the open ocean, is important for understanding what contributes to thermal resilience of coral communities and predicting their response to future anomalies. In June 2014, a field experiment conducted at Dongsha Atoll in the northern South China Sea investigated the physical forces that drive flow over a broad shallow reef flat. Instrumentation included current and pressure sensors and a distributed temperature sensing system, which resolved spatially and temporally continuous temperature measurements over a 3‐km cross‐reef section from the lagoon to reef crest. Spectral analysis shows that while diurnal variability was significant across the reef flat—a result expected from daily solar heating—temperature also varied at higher frequencies near the reef crest. These spatially variable temperature regimes, or thermal microclimates, are influenced by circulation on the wide reef flat, with spatially and temporally variable contributions from tides, wind, and waves. Through particle tracking simulations, we find the residence time of water is shorter near the reef crest (3.6 h) than near the lagoon (8.6 h). Tidal variability in flow direction on the reef flat leads to patterns in residence time that are different than what would be predicted from unidirectional flow. Circulation on the reef also determines the source (originating from offshore vs. the lagoon) of the water present on the reef flat.
    Description: We thank S. Tyler, and J. Selker from the Center for Transformative Environmental Monitoring Programs (CTEMPs), funded by the National Science Foundation (EAR awards 1440596 and 1440506), for timely and effective provision of experimental design support, logistical support and equipment for the project. Support for S. Lentz is from NSF Grant No. OCE‐1558343. Support for A. Cohen from NSF Grant No. 1220529, by the Academia Sinica (Taiwan) through a thematic project grant to G. Wong and A. Cohen. Support for E. Reid and K. Davis is from National Science Foundation (NSF) Grant No. OCE‐1753317, and support to E. Reid from the Environmental Engineering Henry Samueli Endowed Fellowship and the UCI Oceans Graduate Fellowship.
    Description: 2021-05-23
    Keywords: Coral reef ; Distributed temperature sensing ; Temperature variability
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...