Data sets for the Upper Penticton Creek watershed experiment: A paired-catchment study to support investigations of watershed response to forest dynamics and climatic variability in an inland snow-dominated region     

R. Dan Moore  Diana Allen  Lucy MacKenzie  David Spittlehouse  Rita Winkler 《水文研究》2021,35(10):e14391

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The impact and rotational light curves of Comet 9P/Tempel 1     

Jean Manfroid  Damien Hutsemékers  Anita L. Cochran  William M. Jackson  Rita Schulz 《Icarus》2007,187(1):144-155

UVES and HIRES high-resolution spectra of Comet 9P/Tempel 1 are used to investigate the impact and rotational light curves of various species with a view toward building a simple model of the distribution and activity of the sources. The emission by OH, NH, CN, C₃, CH, C₂, NH₂, and OI, are analyzed, as well as the light scattered by the dust. It is found that a simple model reproduces fairly well the impact light curves of all species combining the production of the observed molecules and the expansion of the material throughout the slit. The impact light curves are consistent with velocities of 400-600 m/s. Their modeling requires a three-step dissociation sequence “Grand-Parent → Parent → Daughter” to produce the observed molecules. The rotational light curve for each species is explained in terms of a single model with three sources. The dust component can however not easily be explained that way.  相似文献   

Cyclone track forecasting based on satellite images using artificial neural networks     

Rita Kovordányi  Chandan Roy 《ISPRS Journal of Photogrammetry and Remote Sensing》2009,64(6):513-521

Many places around the world are exposed to tropical cyclones and associated storm surges. In spite of massive efforts, a great number of people die each year as a result of cyclone events. To mitigate this damage, improved forecasting techniques must be developed. The technique presented here uses artificial neural networks to interpret NOAA-AVHRR satellite images. A multi-layer neural network, resembling the human visual system, was trained to forecast the movement of cyclones based on satellite images. The trained network produced correct directional forecast for 98% of test images, thus showing a good generalization capability. The results indicate that multi-layer neural networks could be further developed into an effective tool for cyclone track forecasting using various types of remote sensing data. Future work includes extension of the present network to handle a wide range of cyclones and to take into account supplementary information, such as wind speeds, water temperature, humidity, and air pressure.  相似文献   

Geochronological study of the Monte Amiata Lavas (Central Italy)     

G. Bigazzi  O. Giuliani  F. P. Bonadonna  C. Ghezzo  F. Rita  F. Radicati  Di Brozolo 《Bulletin of Volcanology》1981,44(3):455-465

K/Ar and fission track age measurements were performed on lava samples of Monte Amiata volcano (Central Italy) which is formed by a sequence of lava flows and lava domes ranging in composition from trachybasalts to high-SiO₂ quartzlatites. The ages obtained, except for the oldest volcanic products, range from 290,000 to 180,000 years. Excess⁴⁰Ar was found in some mineral separates, especially biotite, causing apparent rather old ages. The correct ages were calculated by means of K/Ar isochrons, and were found to be very similar to the ages calculated on sanidine separates. The volcanic activity that built up the outcropping Monte Amiata units seems to have lasted a relatively short time.  相似文献   

Acid and basic late neogene volcanism in central aegean sea: Its nature and geotectonic significance     

F. Innocenti  N. Kolios  P. Manetti  F. Rita  L. Villari  L. Villari 《Bulletin of Volcanology》1982,45(2):87-97

Local eruptions of acid volcanic rocks occurred in the Central Aegean region around the Miocene-Pliocene boundary. Rhyolites outcrop on the Island of Antiparos, located in the central part of the Attic-Cycladic Massif. The age of these volcanic rocks ranges from 4.0 to 5.4 m.y., and chemical and Sr isotopic data suggest they were generated by partial melting of the continental crust. At the same time, along the border of the Attic-Cycladic Massif,i.e. on the island of Patmos and Caloyeri, local eruptions of Naalkaline basalts occurred. The whole of the eruptive activity is interpreted as an expression of the marked tensional tectonic phase which has affected the Central Aegean area since Middle Miocene. The contrasting nature of the erupted volcanic rocks (crustal and sub-crustal) is attributed to the different thermal state of the lithosphere beneath the two areas, as emphasized also by the presence of a wide granitic belt, of mainly Miocene age, which developed in the median sector of the Attic-Cycladic Massif.  相似文献   

Petrogenesis of the Eocene and Mio–Pliocene alkaline basaltic magmatism in Meseta Chile Chico, southern Patagonia, Chile: Evidence for the participation of two slab windows     

Felipe Espinoza  Diego Morata  Ewan Pelleter  Ren  C. Maury  Manuel Su  rez  Yves Lagabrielle  Mireille Polv    Herv  Bellon  Joseph Cotten  Rita De la Cruz  Christelle Guivel 《Lithos》2005,82(3-4):315-343

The Meseta Chile Chico (MCC, 46.4°S) is the westernmost exposure of Eocene (lower basaltic sequence, LBS; 55–40 Ma, K–Ar ages) and Mio–Pliocene (upper basaltic sequence, UBS; 16–4 Ma, K–Ar ages) flood basalt volcanism in Patagonia. The MCC is located south of the Lago General Carrera-Buenos Aires (LGCBA), southeast from the present day Chile Triple Junction (CTJ), east of the actual volcanic gap between Southern South Volcanic Zone and Austral Volcanic Zone (SSVZ and AVZ, respectively) and just above the inferred location of the South Chile Ridge segment subducted at 6 Ma (SCR-1). Erupted products consist of mainly ne-normative olivine basalt with minor hy-normative tholeiites basalt, trachybasalt and basanite. MCC lavas are alkaline (42.7–53.1 wt.% SiO₂, 3–8 wt.% Na₂O+K₂O) and relatively primitive (Ni: 133–360 ppm, Cr: 161–193 ppm, Co: 35–72 ppm, 4–16.5 MgO wt.%). They have a marked OIB-like signature, as shown by their isotopic compositions (⁸⁷Sr/⁸⁶Sr_o=0.70311–0.70414 and εNd=+4.7–+5.1) and their incompatible trace elements ratios (Ba/La=10–20, La/Nb=0.46–1.09, Ce/Pb=15.52–27.5, Sr/La<25), reflecting deep mantle origin. UBS-primitive lavas have characteristics similar to those of the Eocene LBS basalts, while UBS-intermediate lavas show geochemical imprints (La/Nb>1, Sr/La>25, low Ce/Pb, Nb/U) compatible with contamination by arc/slab-derived and/or crustal components. We propose that the genesis and extrusion of magmas is related to the opening of two slab windows due to the subduction of two active ridge segments beneath Patagonia during Eocene and Mio–Pliocene.  相似文献   

Refractory organic carbon in particle-size fractions of arable soils I: distribution of refractory carbon between the size fractions   总被引：2，自引：0，他引：2  

Rita Kiem  Heike Knicker  Ingrid Kgel-Knabner 《Organic Geochemistry》2002,33(12)

Refractory compounds are responsible for the long-term sequestration of organic matter in soil. The aim of this study is to assess the storage of refractory compounds, i.e. compounds with long turnover times, across size separates in arable soils. The contents and distribution of organic carbon (OC) and nitrogen (N) in size fractions were examined for two contrasting treatment types from long-term agroecosystem experiments, i.e. C-depleted and fertilized plots. The soil organic carbon (SOC) pool of the C-depleted plots is considered to be relatively enriched in refractory compounds compared with the SOC in the fertilized counterparts. In two of the three long-term experiments, the relative retention of OC in separates <20 μm was considerably higher than in separates 2000–20 μm (OC contents in depleted plots compared with fertilized plots). Highest residual contents of OC were found in fractions <6 μm. In the third experiment, additionally to the very fine fractions, separates 250–20 μm retained a high proportion of OC. The behavior of N was analogous to that of OC: the highest relative residues in the depleted plots were found in fine separates. These results indicate that in the investigated arable soils, C and N compounds associated with fine separates are most stable. Refractory OC in arable soils may be largely stored in fine particle-size fractions.  相似文献   

Global climate models as forcing for regional ocean modeling: a sensitivity study in the Iberian Basin (Eastern North Atlantic)     

Ana Cordeiro Pires  Rita Nolasco  Alfredo Rocha  Alexandre M. Ramos  Jesus Dubert 《Climate Dynamics》2014,43(3-4):1083-1102

This work evaluates the performance of several global climate models (GCMs) as forcing of a regional ocean model configuration centered in the Iberian Basin. The study is divided in two parts. First, the output of nine GCMs is analyzed based on the fields needed to force the ocean model (Regional Ocean Modelling System—ROMS). GCMs differ greatly between them and their performance depends on the field. In the second part, the two GCMs with the worst performances in both extremes of the ensemble are used as forcing for two ROMS simulations, with the purpose of assessing the range of uncertainty comprised in this set of GCMs. Two other ROMS runs are setup: one climatologically forced control run, and one forced with the average of all the nine GCMs—the ensemble mean. Results show that the tendency of overestimation/underestimation of the forcings is reflected in the modeled hydrography, both at the surface and deeper layers down to 500 m. Nevertheless, in terms of circulation, all four runs reproduce the Azores Current, as well as the coastal transition zone seasonality (winter poleward flow and summer upwelling-associated equatorward flow). The CGCMs output performance as forcing depends on the forcing variable: one performs well for one or more variables, but badly for others, and which field is well or badly reproduced varies for each CGCM. Therefore, there is not a single CGCM having the best forcing for all variables. Hence, our results indicate that the most adequate approach consists of using the ensemble mean as forcing rather than using an individual model. This is supported by the general low overall (i.e. for all forcing variables) errors of the ensemble mean regarding the control climatological dataset, and the good comparison of the ensemble-forced ROMS run with the control run.  相似文献   

Rebel Cities: From the Right to the City to the Urban Revolution by David Harvey. Verso,London and New York, 2013, 206 pages (ISBN‐13: 978‐1‐78168‐074‐2) (pbk).     

Rita Padawangi 《Singapore journal of tropical geography》2014,35(2):285-286

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The Growth of the Planetary Boundary Layer at a Coastal Site: a Case Study   总被引：2，自引：1，他引：1  

Ferdinando De Tomasi  M. Marcello Miglietta  M. Rita Perrone 《Boundary-Layer Meteorology》2011,139(3):521-541

A lidar system is used to determine the diurnal evolution of the planetary boundary layer (PBL) height on a summer day characterized by anticyclonic conditions. The site is located some 15 km distant from the sea, on a peninsula in south-east Italy. Contrary to expectations, the PBL height, after an initial growth consequent to sunrise, ceases to increase about 2 h before noon and then decreases and stabilizes in the afternoon. An interpretation of such anomalous behaviour is provided in terms of trajectories of air parcels towards the lidar site, which are influenced by the sea breeze, leading to a transition from a continental boundary layer to a coastal internal boundary layer. The results are analyzed using mesoscale numerical model simulations and a simple model that allows for a more direct interpretation of experimental results.  相似文献