The Thermodynamic Structure of Arctic Coastal Fog Occurring During the Melt Season over East Greenland     

Gaëlle F. Gilson  Hester Jiskoot  John J. Cassano  Ismail Gultepe  Timothy D. James 《Boundary-Layer Meteorology》2018,168(3):443-467

An automated method to classify Arctic fog into distinct thermodynamic profiles using historic in-situ surface and upper-air observations is presented. This classification is applied to low-resolution Integrated Global Radiosonde Archive (IGRA) soundings and high-resolution Arctic Summer Cloud Ocean Study (ASCOS) soundings in low- and high-Arctic coastal and pack-ice environments. Results allow investigation of fog macrophysical properties and processes in coastal East Greenland during melt seasons 1980–2012. Integrated with fog observations from three synoptic weather stations, 422 IGRA soundings are classified into six fog thermodynamic types based on surface saturation ratio, type of temperature inversion, fog-top height relative to inversion-base height and stability using the virtual potential temperature gradient. Between 65–80% of fog observations occur with a low-level inversion, and statically neutral or unstable surface layers occur frequently. Thermodynamic classification is sensitive to the assigned dew-point depression threshold, but categorization is robust. Despite differences in the vertical resolution of radiosonde observations, IGRA and ASCOS soundings yield the same six fog classes, with fog-class distribution varying with latitude and environmental conditions. High-Arctic fog frequently resides within an elevated inversion layer, whereas low-Arctic fog is more often restricted to the mixed layer. Using supplementary time-lapse images, ASCOS microwave radiometer retrievals and airmass back-trajectories, we hypothesize that the thermodynamic classes represent different stages of advection fog formation, development, and dissipation, including stratus-base lowering and fog lifting. This automated extraction of thermodynamic boundary-layer and inversion structure can be applied to radiosonde observations worldwide to better evaluate fog conditions that affect transportation and lead to improvements in numerical models.  相似文献   

Taking correlations in GPS least squares adjustments into account with a diagonal covariance matrix   总被引：1，自引：1，他引：0  

Gaël Kermarrec  Steffen Schön 《Journal of Geodesy》2016,90(9):793-805

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Волна охлаждения в оьолочках сверхновых звëзд     

Э. К. Грасьерг  Д. К. Надëжин 《Astrophysics and Space Science》1976,44(2):429-449

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A new high-grain,broadband, steerable array to study Jovian decametric emission     

A. Boischot  C. Rosolen  M.G. Aubier  G. Daigne  F. Genova  Y. Leblanc  A. Lecacheux  J. De La Noë 《Icarus》1980,43(3):399-407

A large array of antennae has been built at the Radioastronomy Observatory, Nancay, France, to study solar and planetary decametric emissions. This array has a high gain (25 db) in a broad range of frequencies and is steerable through a large part of the sky. We present the main characteristics of this array, and the receives which are used to show the importance of the equipment for Jovian studies. We summarize the results already obtained and describe some topics which are presently being studied.  相似文献   

The seismological picture of the inner core: structure and rotation     

Annie Souriau  Raphaël Garcia  Georges Poupinet 《Comptes Rendus Geoscience》2003,335(1):51-63

This paper presents a review of recent results concerning the structure and the rotation of the inner core, as inferred from seismological observations. We first focus on the apparent hemispherical pattern of the inner core structure, observed in both the anisotropy and the heterogeneity of the uppermost layers, whereas isotropic velocities seem to be homogeneous in a broad wavelength domain. Then we present results on the radial variations of the attenuation and its possible anisotropy, for which viscoelasticity and wave scattering provide complementary explanations. Linked to these results is a discussion about the detection of the PKJKP phase, which propagates as S-wave inside the inner core. Finally, the seismological observations of a possible inner core rotation are discussed; recent results seem to favour rotation rates below 0.2° yr^?1.  相似文献   

Buchbesprechungen     

F. Steinhauser  P. Courvoisier  E. Stenz  H. Israël  Th. Zingg  H. Reuter  W. Mörikofer  J. Lukesch  M. Toperczer 《Meteorology and Atmospheric Physics》1950,2(2-3):345-366

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Le brouillard dans les alpes valaisannes     

Max Bouët 《Theoretical and Applied Climatology》1952,4(1):26-33

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Galactic Constraints on Fermionic Dark Matter     

A. Krut  C. R. Arguëlles  J. Rueda  R. Ruffini 《Astronomy Reports》2018,62(12):898-904

In order to explain Galactic structures, a self-gravitating system composed of massive fermions in spherical symmetry is considered. The finite mass distribution of such a component is obtained after solving the Einstein equation for a thermal and semi-degenerate fermionic gas, described by a perfect fluid in hydrostatic equilibrium and exposed to cutoff effects (e.g. evaporation). Within this more general approach a family of density profiles arises, which explains dark matter halo constraints of the Galaxy and provides at the same time an alternative to the central black hole scenario in Sgr A*. This analysis narrows the allowed particle mass to mc² = 48?345 keV.  相似文献   

Relative current effect on short wave growth     

Guimarães  Pedro Veras  Ardhuin  Fabrice  Perignon  Yves  Benetazzo  Alvise  Bouin  Marie-Noëlle  Garnier  Valerie  Redelsperger  Jean-Luc  Accensi  Mickael  Thomson  Jim 《Ocean Dynamics》2022,72(8):621-639

Ocean Dynamics - Short waves growth is characterized by nonlinear and dynamic processes that couple ocean and atmosphere. Ocean surface currents can have a strong impact on short wave steepness and...  相似文献   

Neogene tectonostratigraphic history of the southern Neuquén basin (39°–40°30′S,Argentina): implications for foreland basin evolution          下载免费PDF全文

Damien Huyghe  Cédric Bonnel  Bertrand Nivière  Bertrand Fasentieux  Yves Hervouët 《Basin Research》2015,27(5):613-635

Although the Neuquén basin in Argentina forms a key transitional domain between the south‐central Andes and the Patagonian Andes, its Cenozoic history is poorly documented. We focus on the sedimentologic and tectonic evolution of the southern part of this basin, at 39–40°30′S, based on study of 14 sedimentary sections. We provide evidence that this basin underwent alternating erosion and deposition of reworked volcaniclastic material in continental and fluvial settings during the Neogene. In particular, basement uplift of the Sañico Massif, due to Late Miocene–Pliocene intensification of tectonic activity, led to sediment partitioning in the basin. During this interval, sedimentation was restricted to the internal domain and the Collon Cura basin evolved towards an endorheic intermontane basin. From stratigraphic interpretation, this basin remained isolated 7–11 Myr. Nevertheless, ephemeral gateways seem to have existed, because we observe a thin succession downstream of the Sañico Massif contemporaneous with the Collon Cura basin‐fill sequence. Comparisons of stratigraphic, paleoenvironmental and tectonic features of the southern Neuquén basin with other foreland basins of South America allow us to classify it as a broken foreland with the development of an intermontane basin from Late Miocene to Late Pliocene. This implies a thick‐skinned structural style for this basin, with reactivation of basement faults responsible for exhumation of the Sañico Massif. Comparison of several broken forelands of South America allows us to propose two categories of intermontane basins according to their structural setting: subsiding or uplifted basins, which has strong implications on their excavation histories.  相似文献