A GIS-based method for defining snow zones: application to the western United States     

Cara Moore  Brandon Stone  Eric Richer 《国际地球制图》2015,30(1):62-81

This study maps the geographic extent of intermittent and seasonal snow cover in the western United States using thresholds of 2000–2010 average snow persistence derived from moderate resolution imaging spectroradiometer snow cover area data from 1 January to 3 July. Results show seasonal snow covers 13% of the region, and intermittent snow covers 25%. The lower elevation boundaries of intermittent and seasonal snow zones increase from north-west to south-east. Intermittent snow is primarily found where average winter land surface temperatures are above freezing, whereas seasonal snow is primarily where winter temperatures are below freezing. However, temperatures at the boundary between intermittent and seasonal snow exhibit high regional variability, with average winter seasonal snow zone temperatures above freezing in west coast mountain ranges. Snow cover extent at peak accumulation is most variable at the upper elevations of the intermittent snow zone, highlighting the sensitivity of this snow zone boundary to climate conditions.  相似文献   

A CH₃CN and HCO⁺ survey towards southern methanol masers associated with star formation     

C. R. Purcell  R. Balasubramanyam  M. G. Burton  A. J. Walsh  V. Minier  M. R. Hunt-Cunningham  L. L. Kedziora-Chudczer  S. N. Longmore  T. Hill  I. Bains  P. J. Barnes  A. L. Busfield  P. Calisse  N. H. M. Crighton  S. J. Curran  T. M. Davis  J. T. Dempsey  G. Derragopian  B. Fulton  M. G. Hidas  M. G. Hoare  J.-K. Lee  E. F. Ladd  S. L. Lumsden  T. J. T. Moore  M. T. Murphy  R. D. Oudmaijer  M. B. Pracy  J. Rathborne  S. Robertson  A. S. B. Schultz  J. Shobbrook  P. A. Sparks  J. Storey  T. Travouillion 《Monthly notices of the Royal Astronomical Society》2006,367(2):553-576

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Radial distribution and strong lensing statistics of satellite galaxies and substructure using high-resolution ΛCDM hydrodynamical simulations     

Andrea V. Macciò  Ben Moore  Joachim Stadel  Jürg Diemand 《Monthly notices of the Royal Astronomical Society》2006,366(4):1529-1538

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Thermal equilibrium in Europa's ice shell     

William B. Moore 《Icarus》2006,180(1):141-146

Models of tidal-convective equilibrium for Europa's ice shell are computed using a laboratory-derived composite flow law for ice. Volume diffusion creep is found to dominate the flow law at equilibrium, and thus the thickness of the shell is strongly dependent on the poorly known grain size of the ice. This grain size is, however, constrained to be less than a few millimeters if equilibrium is achieved at the current eccentricity. Europa's ice shell cannot be thinner than about 16 km in equilibrium at present, since tidal dissipation cannot generate enough heat in such a thin shell to balance the heat transport. No conductive equilibria are found; this is likely due to the fact that most of a conductive shell must be cold if temperature gradients are to be large enough to carry the heat. A minimum eccentricity of about 0.0025 (about 1/4 the present value) below which there are no equilibria is also found.  相似文献   

Morphological evolution of discs in clusters     

Chiara Mastropietro  Ben Moore  Lucio Mayer  Victor P. Debattista  Rocco Piffaretti  Joachim Stadel 《Monthly notices of the Royal Astronomical Society》2005,364(2):607-619

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Large impact features on middle-sized icy satellites     

Jeffrey M. Moore  Paul M. Schenk  Erik Asphaug 《Icarus》2004,171(2):421-443

All of the large impact features of the middle-sized icy satellites of Saturn and Uranus that were clearly observed by the Voyager spacecraft are described. New image mosaics and stereo-and-photoclinometrically-derived digital elevation models are presented. Landforms related to large impact features, such as secondary craters and possible antipodal effects are examined and evaluated. Of the large impacts, Odysseus on Tethys appears to have had the most profound effect on its “target” satellite of any of the impact features we examined. Our modeling suggests that the Odysseus impact may have caused the prompt formation of Ithaca Chasma, a belt of tectonic troughs that roughly follow a great circle normal to the center of Odysseus, although other hypotheses remain viable. We identify probable secondary cratering from Tirawa on Rhea. We attribute a number of converging coalescing crater chains on Rhea to a putative, possibly relatively fresh, ∼350 km-diameter impact feature. We examine the antipodes of Odysseus, the putative ∼350 km-diameter Rhean impact feature, and Tirawa, and conclude that evidence from Voyager data for damage from seismic focusing is equivocal, although our modeling results indicate that such damage may have occurred. We propose a number of observations and tests for Cassini that offer the opportunity to differentiate among the various explanations and speculations reviewed and evaluated in this study.  相似文献   

Rainfall interception by trees of Pinus radiata,and Eucalyptus viminalis,in a 1300 mm rainfall area of southeastern New South Wales: I. Gross losses and their variability     

E. W. Pook  P. H. R. Moore  T. Hall 《水文研究》1991,5(2):127-141

Interception loss, I, was determined by continuous concurrent measurements of the canopy precipitation balances of a mature seed orchard tree of Pinus radiata, and a dominant tree of Eucalyptus viminalis at a mountainous high rainfall site (900 m a.s.l.) in Tallaganda State Forest of the Upper Shoalhaven Catchment. Approximate canopy storage capacity (Sc) of the pine was 54 l, and that of the eucalypt was 11·3 l. Gross pine I was 26·5 per cent and eucalypt I was 8·3 per cent of total incident rainfall over a period of 18 months, from June 1975 to December 1976. The exponential model that provided the best fit to overall data relating I to gross rainfall (P_g) was of good precision for the pine (r² = 0·73) but rather poor precision for the eucalypt (r² = 0·27). A consistent pattern in interception data of the two canopy types suggested that variation in I was related to change in pervasive conditions influencing rates of evaporation from wet canopies during rainfall. Multiple regression analyses confirmed that factors such as rainfall intensity and windspeed explained some of the variation in eucalypt I but little in pine I. Negative eucalypt I and corresponding low values of pine I over a wide range of P_g (up to 20 mm) suggest that capture of wind-borne precipitation (cloud, mist, or fog) had also complicated the canopy precipitation balances.  相似文献   

Authors' reply to 'A comment on 'Frictional heating on a fault zone with finite thickness'     

R. K. Cardwell  D. S. Chinn  G. F. Moore  D. L. Turcotte 《Geophysical Journal International》1979,56(1):239-240

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Guest editors' preface     

Moore  R. Schanda  E. 《Oceanic Engineering, IEEE Journal of》1984,9(5):289-290

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THE CANYONLANDS METEORITE     

David E. Lange  Kent Frost  Paul P. Sipiera  Carleton B. Moore 《Meteoritics & planetary science》1974,9(4):271-280

The Canyonlands meteorite weighing 1,520 grams was found near the confluence of the Green and Colorado Rivers, Utah, near lat 38°11′N.; long 109°53′W. It is a shocked, brecciated H6 chondrite containing large black veins which do not differ in composition from the main chondritic mass. A black fusion crust remains on part of the meteorite.  相似文献