Paleoceanography: T. J. M. SchopfHarvard University Press,Cambridge, MA., U.S.A., 1980, 341 pp., £15     

J.B. Wilson 《Estuarine, Coastal and Shelf Science》1983,16(4):470-471

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Structure of a sunspot     

P. R. Wilson  P. S. McIntosh 《Solar physics》1969,10(2):370-383

From enlargements of patrol photographs of the disk passage of the sunspot of July 20 – August 2, 1966, intensity profiles across the spot are obtained at several positions near the disk-center and at each limb. It is found that these profiles show asymmetric features near each limb (increasingly sharp limb-side penumbra and poorly resolved disk-side penumbra) which are similar to those reported in Paper III of this series. It is suggested that these profile asymmetries are the essential feature of the center-limb variations in the appearance of a sunspot which have become known as the Wilson effect.Conventionally the Wilson effect is described as the extreme foreshortening and eventual disappearance of the disk-side penumbra and, recently, Suzuki has referred to this as the occultation of the penumbra by the photosphere. We find no evidence at all for the disappearance of the disk-side penumbra at the limb in this spot. Defining half-height points on the profile curves as the umbral and penumbral boundaries, we find that, near the west limb where the spot is stable and regular, the limb-side penumbra increases by about 10% at the expense of the umbra. This result qualitatively supports the results reported in Paper III although it is smaller in magnitude.Other observations of sunspots which appear to exhibit the conventional Wilson effect are discussed and it is concluded that in no case yet published is the resolution and seeing of sufficient quality to demonstrate unambiguously the disappearance of the disk-side penumbra.  相似文献   

Magnetic Remanence Related to Slow Rotation of Ferromagnetic Material in Alternating Magnetic Fields     

R. L. Wilson  R. Lomax 《Geophysical Journal International》1972,30(3):295-303

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Center limb observations of inhomogeneities in the solar atmosphere     

P. R. Wilson  C. D. Evans 《Solar physics》1971,18(1):29-39

High resolution Ca II K-line spectra obtained at Kitt Peak National Observatory in September 1970 at a dispersion of 20 mm/Å and a spatial resolution approaching 1 arc sec are described.We first investigate the claim made by Zirin, Pasachoff and others that, at high spatial resolution, the K₂ emission occurs either in the red wing or the blue but not both. In fact, it is shown that although some spectra exhibit predominantly singly-peaked emission features, other spectra, at equally high spatial resolution, show mainly doubly-peaked structures. We suggest that both types of spectra may be regarded as normal.Secondly, time series studies reveal at least two cases in which features exhibiting single emission peaks in either the red or the blue wings evolve into doubly-peaked structures in a time scale of 15sec.Finally, two features on the slit are observed to separate in a manner which implies velocities of order 50 km/sec. Other alternative explanations of the phenomena are discussed but are found to be even more implausible than velocities of this magnitude. Nevertheless, we urge the need for independent confirmation of this result.The implications of these observations for inhomogeneous models for the formation of the Caii K-line are discussed.Operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation.  相似文献   

On Measuring Net Ecosystem Carbon Exchange Over Tall Vegetation on Complex Terrain   总被引：21，自引：2，他引：19  

Dennis Baldocchi  John Finnigan  Kell Wilson  K. T. Paw U  Eva Falge 《Boundary-Layer Meteorology》2000,96(1-2):257-291

To assess annual budgets of CO₂ exchange betweenthe biosphere and atmosphere over representativeecosystems, long-term measurements must be made overecosystems that do not exist on ideal terrain. How tointerpret eddy covariance measurements correctlyremains a major task. At present, net ecosystemCO₂ exchange is assessed, by members of themicrometeorological community, as the sum of eddycovariance measurements and the storage of CO₂ inthe underlying air. This approach, however, seemsunsatisfactory as numerous investigators are reportingthat it may be causing nocturnal respiration fluxdensities to be underestimated.A new theory was recently published by Lee (1998, Agricultural and Forest Meteorology 91: 39–50) for assessing net ecosystem-atmosphere CO₂ exchange(N_e) over non-ideal terrain. Itincludes a vertical advection term. We apply thisequation over a temperate broadleaved forest growingin undulating terrain. Inclusion of the verticaladvection term yields hourly, daily and annual sums ofnet ecosystem CO₂ exchange that are moreecologically correct during the growing season.During the winter dormant period, on the other hand,corrected CO₂ flux density measurements of anactively respiring forest were near zero. Thisobservation is unrealistic compared to chambermeasurements and model calculations. Only duringmidday, when the atmosphere is well-mixed, domeasurements of N_e match estimatesbased on model calculations and chamber measurements. On an annual basis, sums of N_ewithout the advection correction were 40% too large,as compared with computations derived from a validatedand process-based model. With the inclusion of theadvection correction term, we observe convergencebetween measured and calculated values ofN_e on hourly, daily and yearly time scales. We cannot, however, conclude that inclusion of aone-dimensional, vertical advection term into thecontinuity equation is sufficient for evaluatingCO₂ exchange over tall forests in complexterrain. There is an indication that the neglected term,( c¯/ x), isnon-zero and that CO₂ may be leakingfrom the sides of the control volume during the winter. In this circumstance, forest floor CO₂ effluxdensities exceed effluxes measured above the canopy.  相似文献   

DEFORMATIONAL AND METAMORPHIC HISTORY OF THE CENTRAL LONGMEN MOUNTAINS, SICHUAN CHINA     

Chris J.L. Wilson  Brenton A. Worley  Shefa Chen  Mathew J. Harrowfield  Liu Shugen  Luo Zhili WT  ”BX 《地学前缘》2000,(Z1)

DEFORMATIONAL AND METAMORPHIC HISTORY OF THE CENTRAL LONGMEN MOUNTAINS, SICHUAN CHINA1　ArneDC ,WorleyBA ,WilsonCJL ,etal.Differentialexhumationinresponsetoepisodicthrustingalongtheeasternmar ginoftheTibetanPlateau[J] .Tectonophysics,1997,2 80 :2 39～ 2 56 . 2　ChenSF ,WilsonCJL ,WorleyBA .TectonictransitionfromtheSongpan GarzeFoldBelttotheSichuanBasin,south westernChina[J] .BasinResearch ,1995,7:2 35～ 2 53. 3　ChenSF ,WilsonCJL .Emplaceme…  相似文献   

Particle trapping in stratified estuaries: Application to observations   总被引：1，自引：0，他引：1  

David A. Jay  Philip M. Orton  Thomas Chisholm  Douglas J. Wilson  Annika M. V. Fain 《Estuaries and Coasts》2007,30(6):1106-1125

Estuarine turbidity maxima (ETM) retain suspended particulate matter (SPM) through advection, settling, aggregation, and nonlinearities in bed processes, but the relative importance of these processes varies strongly between systems. Observations from two strongly advective systems (the Columbia and Fraser Rivers) are used to investigate seasonal cycles of SPM retention and the effects of very high flows. Results for the Fraser and Columbia plus literature values for 13 other estuaries illustrate the applicability of scaling parameters and the response of ETM phenomena to a range of river flow (U _r ) levels and tidal forcing. The most efficient trapping (represented by Trapping EfficiencyE, the ratio of maximum ETM concentration to the source SPM concentration) occurs for low ratios of river flow to tidal current amplitude (U_T), represented by low values of the Supply number S_r.E in the Columbia is found to be maximal in a null zone where advection or tidal asymmetry (represented by Advection numberA) is weak(A ∼ 0). The ratio of aggregation to disaggregation (the Floc number Θ) is maximal on neap tides, while the ratio of erosion to deposition (the Erosion number P) is maximal on spring tides. The ratio of settling velocity to vertical mixing (Rouse numberP) is relatively constant in the Columbia ETM(P ∼ 0.7), because particle settling velocity and turbulence levels adjust together. Assuming that this result applies broadly, scaling variables and data are combined to express ETM properties in terms of the friction velocity (U_*),U _r , andU _T , allowing a considerable simplification of the parameters used to describe ETM.  相似文献   

The automatic management of drivers and driving spaces     

Martin Dodge  Rob Kitchin 《Geoforum》2007,38(2):264-275

In this paper, we examine the development and implementation of new technical systems designed to more effectively manage and produce driving, drivers and driving spaces. These new systems change the governmentality of automobilities by altering the relationship between driver, vehicle and transport infrastructure and produce new subjects and spaces. They do this principally through the process of automation, creating a system of regulation that we term ‘automated management’. Automated management consists of two interlocking sets of regulatory technologies: automated surveillance that seeks to enforce more effective (self)disciplining and capture systems that actively reshape activity. We argue that these work together to alter the automobilities landscape creating new socio-spatial arrangements with respect to access, movement, flow, and behaviour. Some of these arrangements are benign and empowering to individuals, others enhance the power of state and corporations. We illustrate our argument with examples predominately drawn from the UK, though the technologies we discuss are increasingly being developed and implemented throughout Western countries and beyond.  相似文献   

Forward Lagrangian stochastic simulation of a transient source in the atmospheric surface layer     

E. H. Shadwick  J. D. Wilson  T. K. Flesch 《Boundary-Layer Meteorology》2007,122(2):263-272

We show that a forward Lagrangian stochastic (LS) model simulates well the ensemble-averaged concentration transient due to a short time (5 min) point source in the uniform atmospheric surface layer. In LS models, computational particles, which may not descend below ground level, are necessarily reflected at an imposed (artificial) boundary above ground. Model results were rather insensitive to the placing of the lower reflection boundary, and no definite benefit stemmed from including a parametrization for unresolved delays/displacements beneath the lower boundary.  相似文献   

Spatial coincidence and similar geochemistry of Late Triassic and Eocene–Oligocene magmatism in the Andes of northern Chile: evidence from the MMH porphyry type Cu–Mo deposit,Chuquicamata District     

Zentilli  Marcos  Maksaev  Victor  Boric  Ricardo  Wilson  Jessica 《International Journal of Earth Sciences》2018,107(3):1097-1126

International Journal of Earth Sciences - The MMH porphyry type copper–molybdenum deposit in northern Chile is the newest mine in the Chuquicamata District, one of largest copper...  相似文献