A new class of nearshore waves based on the shear instability of a steady longshore current is discussed. The dynamics depend on the conservation of potential vorticity but with the background vorticity field, traditionally the role of Coriolis in larger scale flows, supplied by the shear structure of the longshore...
A 5-year time series of coastal zone color scanner imagery (1980-1983, 1986) is used to examine
changes in the large-scale pattern of chlorophyll pigment concentration coincident with the spring
transition in winds and currents along the west coast of North America. The data show strong
interannual variability in the timing...
Ambiguity in wind direction has long been an impediment to applications of wind observations from the Seasat scatterometer (SASS). Three months of unambiguous global SASS vector winds (7 July-10 October 1978) have recently become available from the Goddard Space Flight Center(GSFC) Laboratory for Atmospheric Sciences. The directional ambiguities were removed...
Long‐period and broadband body waves from 14 digital seismic stations are used to investigate the rupture process of the December 7, 1988 earthquake near Spitak, Armenia, USSR. The inversion of these data gives the following centroidal source parameters: strike 299°, dip 64°, rake 151°, depth 6.3 km and seismic moment...
We have used the modal expansion of the wave function in the discontinuity region based on the superposition principle together with a mode-matching technique to investigate the transmission characteristics of semiconductor quantum wire structures with discontinuities. Our calculations compare quite well with published results for the theoretical transmission coefficient and...
A magnetotelluric (MT)transect has been obtained near latitude 45øN from the active Juan de Fuca
Spreading center, across the subduction zone and Cascades volcanic arc, and into the back arc Deschutes
Basin region. This paper presents the MT data set and describes its major characteristics as they pertain to
the...
Spectral analysis of the time-varying horizontal magnetic and electric field components yields the magnetotelluric (MT) impedance tensor. This frequency dependent 2x2 complex tensor can be examined for details which axe diagnostic of the electrical conductivity distribution in the Earth within the relevant (frequency dependent) inductive scale length of the surface...
Rockfishes, Sebastes spp.. were the most numerous and speciose fishes seen during 16 submersible dives from 64 to 305 m depth in the vicinity of Heceta Bank off the coast of Oregon. Dense schools of juvenile rockfishes and large yellowtail rockfish, S. flavidus, were observed only over rocky, high relief...
The virus-encoded proteins of tobacco etch virus (TEV), a plant potyvirus, arise by proteolytic processing of
a large polyprotein precursor. The TEV genome codes for two proteinases, a 49-kilodalton proteinase and
helper component proteinase (HC-Pro), which cleave the polyprotein at specific sites. The only known cleavage
event catalyzed by HC-Pro...
High concentrations of the fumigant methylisothiocyanate (MITC) will effectively control decay fungi in large wood structures, but the fungitoxicity of low MITC concentrations and the influence of wood moisture content (MC) on its performance are not well understood. The MC of Douglas-fir heartwood greatly influenced the susceptibility of the decay...
We report paleointensity results of the Earth's
magnetic field from n Late Pleistocene lava flow
(Louchadiere, Central France), which recorded an intermediate
geomagnetic field direction (5 sites, mean declination=
114.1°, inclination=58.2°, k=130, α95=6.7°). New K-Ar
age determinations confirm that this flow is contemporaneous
with the Laschamp and Olby flows, and...
A note of caution is Provided to users of the widely-distributed Cox ocean circulation model. It is shown that the discrete conservation of vorticity equation associated with the finite difference approximations to the primitive equations on an Arakawa B grid contains a term that approximates βΔy²∂²u/∂x∂y. Although this term has...
Thirty-two chemoheterotrophic bacteria were isolated from unsaturated subsurface soil samples obtained from ca. 70 m below land surface in a high desert in southeastern Idaho. Most isolates were gram positive (84%) and strict aerobes (79%). Acridine orange direct counts of microbes in one subsurface sample showed lower numbers than similar...
A procedure has been developed to optimize designs of metal-clad post-frame buildings using an expert system. The novel part of the study is the development of a procedure that extends the solution of an engineering problem from a conventional algorithmic Computer Aided Design (CAD) program to be used by the...
Measurements of upper ocean shear made during the Mixed Layer Dynamics Experiment (MILDEX) provide evidence of large horizontal scale motion at near‐inertial frequency. The measurements consist of shipboard acoustic Doppler current profiles. Four large‐scale spatial surveys of 2–4 days duration were made by the R/V Wecoma as a set of...
Several methods are developed for analyzing data containing a highly variable internal tide. In particular, the methods are aimed at the analysis of moored observations with relatively few measurements in the vertical. The analysis depends upon an "elliptical decomposition" that is a generalization of the familiar "rotary decomposition." The technique...
The Kalman filter is implemented and tested for a simple model of sea level anomalies in the tropical Pacific, using tide gauge data from six selected island stations to update the model. The Kalman filter requires detailed statistical assumptions about the errors in the model and the data. In this...
In four dimensions, two metrics that are conformally related define the same Hodge dual operator on the space of two‐forms. The converse, namely, that two metrics that have the same Hodge dual are conformally related, is established. This is true for metrics of arbitrary (nondegenerate) signature. For Euclidean signature a...
The conventional view of equatorial dynamics requires that the zonal equatorial wind stress be balanced, in the mean, by the vertical integral of “large-scale” terms, such as the zonal pressure gradient, mesoscale eddy flux, and mean advection, over the upper few hundred meters. It is usually presumed that the surface...
Lagrangian equations for momentum and buoyancy are developed for idealized turbulent fluid elements. The resulting formulation of transport can he viewed as a generalization of mixing length and parcel theories of mixing for application to gridded Eulerian models. This formulation of transport recognizes the mean gradients on the scale of...