The formation and fate of internal waves in the South China Sea

Author Posting. © The Author(s), 2015. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature 521 (2015): 65-69, doi:10.1038/nature14399.Internal gravity waves, the subsurface analogue of the familiar surface gravity waves that break on beaches, are ubiquitous in the ocean. Because of their strong vertical and horizontal currents, and the turbulent mixing caused by their breaking, they impact a panoply of ocean processes, such as the supply of nutrients for photosynthesis1, sediment and pollutant transport2 and acoustic transmission3; they also pose hazards for manmade structures in the ocean4. Generated primarily by the wind and the tides, internal waves can travel thousands of kilometres from their sources before breaking5, posing severe challenges for their observation and their inclusion in numerical climate models, which are sensitive to their effects6-7. Over a decade of studies8-11 have targeted the South China Sea, where the oceans’ most powerful internal waves are generated in the Luzon Strait and steepen dramatically as they propagate west. Confusion has persisted regarding their generation mechanism, variability and energy budget, however, due to the lack of in-situ data from the Luzon Strait, where extreme flow conditions make measurements challenging. Here we employ new observations and numerical models to (i) show that the waves begin as sinusoidal disturbances rather than from sharp hydraulic phenomena, (ii) reveal the existence of >200-m-high breaking internal waves in the generation region that give rise to turbulence levels >10,000 times that in the open ocean, (iii) determine that the Kuroshio western boundary current significantly refracts the internal wave field emanating from the Luzon Strait, and (iv) demonstrate a factor-of-two agreement between modelled and observed energy fluxes that enables the first observationally-supported energy budget of the region. Together, these findings give a cradle-to-grave picture of internal waves on a basin scale, which will support further improvements of their representation in numerical climate predictions.Our work was supported by the U.S. Office of Naval Research and the Taiwan National Science Council.2015-10-2

The formation and fate of internal waves in the South China Sea

Internal gravity waves, the subsurface analogue of the familiar surface gravity waves that break on beaches, are ubiquitous in the ocean. Because of their strong vertical and horizontal currents, and the turbulent mixing caused by their breaking, they affect a panoply of ocean processes, such as the supply of nutrients for photosynthesis¹, sediment and pollutant transport² and acoustic transmission³; they also pose hazards for man-made structures in the ocean⁴. Generated primarily by the wind and the tides, internal waves can travel thousands of kilometres from their sources before breaking⁵, making it challenging to observe them and to include them in numerical climate models, which are sensitive to their effects[superscript 6,7]. For over a decade, studies[superscript 8–11] have targeted the South China Sea, where the oceans’ most powerful known internal waves are generated in the Luzon Strait and steepen dramatically as they propagate west. Confusion has persisted regarding their mechanism of generation, variability and energy budget, however, owing to the lack of in situ data from the Luzon Strait, where extreme flow conditions make measurements difficult. Here we use new observations and numerical models to (1) show that the waves begin as sinusoidal disturbances rather than arising from sharp hydraulic phenomena, (2) reveal the existence of >200-metre-high breaking internal waves in the region of generation that give rise to turbulence levels >10,000 times that in the open ocean, (3) determine that the Kuroshio western boundary current noticeably refracts the internal wave field emanating from the Luzon Strait, and (4) demonstrate a factor-of-two agreement between modelled and observed energy fluxes, which allows us to produce an observationally supported energy budget of the region. Together, these findings give a cradle-to-grave picture of internal waves on a basin scale, which will support further improvements of their representation in numerical climate predictions

World Federation of Orthodontists guidelines for postgraduate orthodontic education

Advanced dental education programs in orthodontics and dentofacial orthopedics require an extensive and comprehensive evidence-based experience, which must be representative of the current didactic and technical advancements. Over the past 25 years, the World Federation of Orthodontists (WFO) has placed emphasis in the support for the recognized orthodontic specialty training programs in every region of the world. In its early years, the WFO developed general principles for specialty education that culmi-nated in the first comprehensive curriculum recommendations, i.e., the WFO Guidelines for Postgraduate Orthodontic Education, which was published in February 2009. In view of the significant changes in the specialty of orthodontics, the WFO has revised and updated its previous document to reflect the expanded scope and demands of current orthodontic education and practice. The members of the task force partic-ipated in a thorough revision of the guidelines and created a new document that takes into consideration the didactic, clinical, and the appropriate physical facilities to provide clinical care, study, and research areas. Although it is recognized that there will be variations in teaching and faculty assets, as well as facilities, access to materials, and equipment, the aim of the WFO Educational Guidelines is to provide the minimum program requirements necessary to provide orthodontic specialty residents the educational experience that prepares them to deliver the best level of orthodontic treatment for their patients. It is recommended that these guidelines be used universally by orthodontic specialty program educators and related educational, scientific, and administrative institutions to evaluate and compare their curriculum to a world standard.(c) 2023 World Federation of Orthodontists. Published by Elsevier Inc. All rights reserved

Social Problem Solving as a Predictor of Well-being in Adolescents and Young Adults

Social problem solving, Depression, Anxiety, Family functioning, Well-being,