The deep ocean below 200 m water depth is the least observed, but largest habitat on our planet by volume and area. Over 150 years of exploration has revealed that this dynamic system provides critical climate regulation, houses a wealth of energy, mineral, and biological resources, and represents a vast repository of biological diversity. A long history of deep-ocean exploration and observation led to the initial concept for the Deep-Ocean Observing Strategy (DOOS), under the auspices of the Global Ocean Observing System (GOOS). Here we discuss the scientific need for globally
TOPEX/POSEIDON and ERS‐2 (T/ERS) sea surface height altimeter observations and the Naval Research Laboratory Layered Ocean Model (NLOM) are used to study the circulation along the southwest coast of Mexico. The results of this research indicate that strong El Niño/Southern Oscillation (ENSO) warm phase Kelvin waves (KW) destabilize the upper ocean circulation. The effect of ENSO appears as three distinct stages. First, a coastal jet characterized by strong vertical shear flow develops. Second, the shear flow strengthens, increasing its horizontal dimension and the amplitude of its oscillations. Finally, the jet becomes unstable and breaks into anticyclonic eddies, which separate from the coast and drift southwestward. The genesis and strengthening of the jet is due to the simultaneous occurrence of the poleward‐flowing currents along the southwest coast of Mexico and the poleward circulation associated with ENSO downwelling KW.
Regionally organized winter (DJF) precipitation anomalies over North America are presented in association with cold and warm phases of the ~ Nifio-Southern Oscillation. Variations in low-level flow from moisture sources aDd in upper-level dynamic properties are diagnosed for eKb anomalous precipitation region using DJF composites of upper-and lower-tropospheric winds. sea level pressure. divergence, and vorticity advection. Variance analysis determines which precipitation and circulation patterns are robust and evaluates the predictability of the extreme phase composites with respect to the climatology. In cold phases. the P-=ific Northwest aDd the lower Mississippi Valley regions have above-nonnal precipitation tOtals. The heavier precipitation over the Pacific Northwest is the result of a multilevel onshore flow forced by an amplified Pacific high off the California coast and a single zonal upper-tropospheric jet. In the Lower Mississippi and Tennessee Valleys, the equatorward entrance region of a west-east-oriented jet core combines with anomalous positive vorticity advection (pV A) and a convergent low-level flow off the Gulf of Mexico. resulting in heavier precipitation. Drier than nonnal conditions occur in coastal Aluka aDd California due to negative vorticity advection anomalies aloft, low-level divergence. and weaker onshore ftow. The increased precipitation over the southern Mississippi Valley and the Pacific Northwest, and the drier conditions over Florida. are statistically robust. During warm phases. more precipitation occurs in the coastal regions of Alaska. California, aDd the Gulf of Mexico, whereas drier conditions persist over the Pacific Northwest. Alaskan precipitation is enhanced by strong. convergent. onshore ftow associated with a deeper Aleutian low. upper-level PV A. aDd the northern branch of a split jet pattern. A strong southern subtropical branch of the split jet provides dynamic support for uplift of moisture along the Gulf Coast. The drier conditions in the Pacific Northwest and the wet conditions in Texas aDd Florida are predictable relative to the climatology and are statistically robust.
Sustained observations of oceanographic and atmospheric boundary layer conditions are imperative for the investigation of tropical cyclone genesis, for numerical model input to predict track and intensity, and in general, for many environmental monitoring needs. We present preliminary results of a Fall 2014 100-day deployment of Wave Glider platforms in the eastern Gulf of Mexico designed to dynamically collect surface weather, water temperature, wave, and ocean current profile data within tropical cyclones. Data were collected and retransmitted near real time through a Liquid Robotics interface to regional and national data portals such as the National Data Buoy Center, and secondarily also used by the private sector. Accomplishments include buoy loitering for validation exercises, data gap filling, platform redeployments, and an interception of the fringes of Tropical Storm Hanna. Preliminary buoy loitering assessments using bias and absolute error metrics showed reasonable agreement with buoys for atmospheric pressure, wave, and height-adjusted wind data but that the temperature hardware requires an improved sensor. A full assessment of the potential for the sustained collection and real-time dissemination of environmental data for Wave Glider platforms is presented including lessons learned.
Interannual variability in the eastern subtropical North Pacific Ocean is investigated using the Naval Research Laboratory Layered Ocean Model (NLOM). Emphasis is placed on examining the nature of westward propagating Rossby waves and their interaction with the overlying atmosphere. Singular value decomposition (SVD), complex empirical orthogonal function (CEOF), and multichannel singular spectrum (M-SSA) analyses are used to isolate the standing and propagating response due to modeled Rossby waves and observed wind stress curl (WSC) anomalies as well as their dominant frequencies of oscillation, respectively. In addition to a large-scale interdecadal fluctuation, two distinct forms of Rossby waves are found to exist, one wind forced and the other freely propagating. SVD and CEOF analyses of NLOM upper layer thickness anomalies suggest a leading order source of variability stemming from a large-scale interdecadal fluctuation. M-SSA analysis also depicts this low frequency mode, but to a lesser extent and at higher order. The modeled temporal coverage limits the extent to which this feature can be studied further. Of primary interest in the eastern subtropical North Pacific Ocean are large-scale interannual wind-forced Rossby wave variations. Independent M-SSA analysis of modeled ULT and observed WSC anomalies suggests a low frequency (ϳ51 month period) atmospherically forced ocean response in which westward atmospheric propagation leads forced oceanic Rossby wave propagation by roughly 3 months. In addition to this low frequency forced oceanic wave response with a phase speed of c r ϳ 12 cm s Ϫ1 , a distinct freely propagating biennial oceanic Rossby wave is also found to exist, with a phase speed of c r ϳ 8 cm s Ϫ1 , emanating from El Niño-Southern Oscillation related coastally trapped Kelvin waves.
The designations employed and the presentation of material in this information product do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations (FAO) or the International Union of Forest Research Organizations (IUFRO) or U.S. Department of Agriculture (USDA) concerning the legal or development status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products of manufacturers, whether or not these have been patented, does not imply that these have been endorsed or recommended by FAO or IUFRO or USDA in preference to others of a similar nature that are not mentioned.The views expressed in this information product are those of the author(s) and do not necessarily reflect the views or policies of FAO or IUFRO or USDA.
In 2007 the Swiss Federal Commission for NRBC Protection released a disaster management plan for coping with the aftermath of radiological dispersal devices. This paper summarises the basic concept and outlines the relevant bodies and agencies as well as their responsibilities. It also sets out the strategy to monitor radioactive contamination and the measures to prevent public radiation exposure.
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