Waves in the Red Sea : response to monsoonal and mountain gap winds

Author Posting. © The Author(s), 2013. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Continental Shelf Research 65 (2013): 1-13, doi:10.1016/j.csr.2013.05.017.An unstructured grid, phase-averaged wave model forced with winds from a high resolution atmospheric model is used to evaluate wind wave conditions in the Red Sea over an approximately 2-year period. The Red Sea lies in a narrow rift valley, and the steep topography surrounding the basin steers the dominant wind patterns and consequently the wave climate. At large scales, the model results indicated that the primary seasonal variability in waves was due to the monsoonal wind reversal. During the winter, monsoon winds from the southeast generated waves with mean significant wave heights in excess of 2 m and mean periods of 8 s in the southern Red Sea, while in the northern part of the basin waves were smaller, shorter period, and from northwest. The zone of convergence of winds and waves typically occurred around 19-20˚N, but the location varied between 15 to 21.5˚N. During the summer, waves were generally smaller and from the northwest over most of the basin. While the seasonal winds oriented along the axis of the Red Sea drove much of the variability in the waves, the maximum wave heights in the simulations were not due to the monsoonal winds but instead were generated by localized mountain wind jets oriented across the basin (roughly east-west). During the summer, a mountain wind jet from the Tokar Gap enhanced the waves in the region of 18 and 20˚N, with monthly mean wave heights exceeding 2 m and maximum wave heights of 14 m during a period when the rest of the Red Sea was relatively calm. Smaller mountain gap wind jets along the northeast coast created large waves during the fall and winter, with a series of jets providing a dominant source of wave energy during these periods. Evaluation of the wave model results against observations from a buoy and satellites found that the spatial resolution of the wind model significantly affected the quality of the wave model results. Wind forcing from a 10-km grid produced higher skills for waves than winds from a 30-km grid, largely due to under-prediction of the mean wind speed and wave height with the coarser grid. The 30-km grid did not resolve the mountain gap wind jets, and thus predicted lower wave heights in the central Red Sea during the summer and along the northeast coast in the winter.This research is based on work supported by Award No. USA00001, USA00002, KSA00011, made by the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia

Controlled Delivery of Sdf-1 Alpha and Igf-1: Cxcr4(+) Cell Recruitment and Functional Skeletal Muscle Recovery

Therapeutic delivery of regeneration-promoting biological factors directly to the site of injury has demonstrated its efficacy in various injury models. Several reports describe improved tissue regeneration following local injection of tissue specific growth factors, cytokines and chemokines. Evidence exists that combined cytokine/growth factor treatment is superior for optimizing tissue repair by targeting different aspects of the regeneration response. The purpose of this study was to evaluate the therapeutic potential of the controlled delivery of stromal cell-derived factor-1alpha (SDF-1 alpha) alone or in combination with insulin-like growth factor-I (SDF-1 alpha/IGF-I) for the treatment of tourniquet-induced ischemia/reperfusion injury (TK-I/R) of skeletal muscle. We hypothesized that SDF-1 alpha will promote sustained stem cell recruitment to the site of muscle injury, while IGF-I will induce progenitor cell differentiation to effectively restore muscle contractile function after TK-I/R injury while concurrently reducing apoptosis. Utilizing a novel poly-ethylene glycol PEGylated fibrin gel matrix (PEG-Fib), we incorporated SDF-1 alpha alone (PEG-Fib/SDF-1 alpha) or in combination with IGF-I (PEG-Fib/SDF-1 alpha/IGF-I) for controlled release at the site of acute muscle injury. Despite enhanced cell recruitment and revascularization of the regenerating muscle after SDF-1 alpha treatment, functional analysis showed no benefit from PEG-Fib/SDF-1 alpha therapy, while dual delivery of PEG-Fib/SDF-1 alpha/IGF-I resulted in IGF-I-mediated improvement of maximal force recovery and SDF-1 alpha-driven in vivo neovasculogenesis. Histological data supported functional data, as well as highlighted the important differences in the regeneration process among treatment groups. This study provides evidence that while revascularization may be necessary for maximizing muscle force recovery, without modulation of other effects of inflammation it is insufficient.Kinesiology and Health Educatio

The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2009

From 3 April – 23 September 2009 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Beach, New River, and Floras Lake. Our objectives for the Oregon coastal population in 2009 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) continue selective use of mini-exclosures (MEs) to protect nests from predators and evaluate whether exclosure use can be reduced, 4) determine nest success, 5) determine fledgling success, 6) monitor brood movements, 7) collect general observational data about predators, and 8) evaluate the effectiveness of predator management. We observed an estimated 199-206 adult Snowy Plovers; a minimum of 149-150 individuals was known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990, and we found 236 nests in 2009. Overall Mayfield nest success was 23%. Exclosed nests (n = 34) had a 76% success rate, and unexclosed nests (n = 202) had a 25% success rate. Nest failures were attributed to unknown depredation (29%), rodent depredation (21%), unknown cause (17%), oneegg nests (12%), corvid depredation (8%), abandonment (7%), wave overwash (2%), infertility (1%), wind (1%), canine depredation (1%), and raccoon depredation (1%). We monitored 88 broods, including eight from unknown nests, and documented a minimum of 106 fledglings. Overall brood success was 73%, fledgling success was 50%, and 1.33 fledglings per male were produced. Continued predator management, habitat improvement and maintenance, and management of recreational activities at all sites are recommended to achieve recovery goals

The Distribution and Reproductive Success of the Western Snowy Plover along the Oregon Coast - 2012

From 5 April – 21 September 2012 we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius nivosus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River HRA and adjacent lands, and Floras Lake. Our objectives for the Oregon coastal population in 2012 were to: 1) estimate the size of the adult Snowy Plover population, 2) locate plover nests, 3) determine nest success, 4) use mini-exclosures (MEs) to protect nests from predators as needed, 5) determine fledging success, 6) monitor brood movements, 7) collect general observational data about predators, and 8) evaluate the effectiveness of predator management. We observed an estimated 290-91 adult Snowy Plovers; a minimum of 231-238 individuals was known to have nested. The adult plover population was the highest estimate recorded since monitoring began in 1990. We monitored 314 nests in 2012; the highest number of nests since monitoring began in 1990. Overall apparent nest success was 45%. Exclosed nests (n = 22) had an 82% apparent nest success rate, and unexclosed nests (n = 289) had a 42% apparent nest success rate. Nest failures were attributed to unknown depredation, unknown cause, corvid depredation, abandonment, one egg nests, wind/weather, mammalian depredation, overwashing, adult plover depredation, and infertility. We monitored 154 broods, including 11 from unknown nests, and documented a minimum of 173 fledglings. Overall brood success was 70%, fledging success was 43%, and 1.37 fledglings per male were produced. Continued predator management, habitat improvement and maintenance, and management of recreational activities at all sites are recommended to achieve recovery goals

Comparing air-sea flux measurements from a new unmanned surface vehicle and proven platforms during the SPURS-2 field campaign.

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Zhang, D., Cronin, M. F., Meinig, C., Farrar, J. T., Jenkins, R., Peacock, D., Keene, J., Sutton, A., & Yang, Q. Comparing air-sea flux measurements from a new unmanned surface vehicle and proven platforms during the SPURS-2 field campaign. Oceanography, 32(2), (2019): 122-133, doi:10.5670/oceanog.2019.220.Two saildrones participated in the Salinity Processes in the Upper-ocean Regional Study 2 (SPURS-2) field campaign at 10°N, 125°W, as part of their more than six-month Tropical Pacific Observing System (TPOS)-2020 pilot study in the eastern tropical Pacific. The two saildrones were launched from San Francisco, California, on September 1, 2017, and arrived at the SPURS-2 region on October 15, one week before R/V Revelle. Upon arrival at the SPURS-2 site, they each began a two-week repeat pattern, sailing around the program’s central moored surface buoy. The heavily instrumented Woods Hole Oceanographic Institution (WHOI) SPURS-2 buoy serves as a benchmark for validating the saildrone measurements for air-sea fluxes. The data collected by the WHOI buoy and the saildrones were found to be in reasonably good agreement. Although of short duration, these ship-saildrone-buoy comparisons are encouraging as they provide enhanced understanding of measurements by various platforms in a rapidly changing subsynoptic weather system. The saildrones were generally able to navigate the challenging Intertropical Convergence Zone, where winds are low and currents can be strong, demonstrating that the saildrone is an effective platform for observing a wide range of oceanographic variables important to air-sea interaction studies.The TPOS-2020 saildrone pilot study was funded by the NOAA Ocean Observations and Monitoring Division of the Climate Programs Office. The WHOI flux mooring was funded by NASA as part of the SPURS-2 program. This work is partially funded by the Joint Institute for the Study of the Atmosphere and Ocean (JISAO) under NOAA Cooperative Agreement NA15OAR4320063. We thank SPURS-2 cruise Chief Scientist Kyla Drushka of APL/University of Washington, Fred Bingham of the University of North Carolina, and Dave Rivera of PMEL onboard R/V Revelle for close coordination between ship operation and saildrone piloting. High-quality shipboard air-sea flux measurements by Carol Anne Clayson and James Edson of WHOI are greatly appreciated. We also thank the editors and two anonymous reviewers for their thoughtful suggestions that helped to improve this manuscript. This is PMEL contribution #4899

Inhomogeneous vacuum energy

Vacuum energy remains the simplest model of dark energy which could drive the accelerated expansion of the Universe without necessarily introducing any new degrees of freedom. Inhomogeneous vacuum energy is necessarily interacting in general relativity. Although the four-velocity of vacuum energy is undefined, an interacting vacuum has an energy transfer and the vacuum energy defines a particular foliation of spacetime with spatially homogeneous vacuum energy in cosmological solutions. It is possible to give a consistent description of vacuum dynamics and in particular the relativistic equations of motion for inhomogeneous perturbations given a covariant prescription for the vacuum energy, or equivalently the energy transfer four-vector, and we construct gauge-invariant vacuum perturbations. We show that any dark energy cosmology can be decomposed into an interacting vacuum+matter cosmology whose inhomogeneous perturbations obey simple first-order equations.Comment: 8 pages; v2 clarified discussion of Chaplygin gas model, references adde