Crustal Structure of Israel: Constraints From Teleseismic and Gravity Data   总被引：1，自引：0，他引：1  

Abraham Hofstetter  Lea Feldman  Yair Rotstein 《Geophysical Journal International》1991,104(2):371-379

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Fine-scale linkages between the diving behaviour of Antarctic fur seals and oceanographic features in the southern Indian Ocean   总被引：1，自引：1，他引：1  

Lea  Mary-Anne; Dubroca  Laurent 《ICES Journal of Marine Science》2003,60(5):990-1002

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How do Canadian media report climate change impacts on health? A newspaper review     

King  Nia  Bishop-Williams  Katherine E.  Beauchamp  Sabrina  Ford  James D.  Berrang-Ford  Lea  Cunsolo  Ashlee  Team  IHACC Research  Harper  Sherilee L. 《Climatic change》2019,152(3-4):581-596

Climatic Change - Research on climate change media coverage is growing. Few studies, however, have investigated how the media portrays climate change impacts on human health. This review,...  相似文献   

Sulfur volcanism on Io     

Kandis Lea Jessup  John Spencer 《Icarus》2007,192(1):24-40

In February 2003, March 2003 and January 2004 Pele plume transmission spectra were obtained during Jupiter transit with Hubble's Space Telescope Imaging Spectrograph (STIS), using the 0.1″ wide slit and the G230LB grating. The STIS spectra covered the 2100-3100 Å wavelength regions and extended spatially along Io's limb encompassing the region directly above and northward of the vent of the Pele volcano. The S₂ and SO₂ absorption signatures evident in these data indicate that the gas signature at Pele was temporally variable, and that an S₂ absorption signature was present ∼12° from the Pele vent near 6±5 S and 264±15 W, suggesting the presence of another S₂ bearing plume on Io. Contemporaneous with the spectral data, UV and visible-wavelength images of the plume were obtained in reflected sunlight with the Advanced Camera for Surveys (ACS) prior to Jupiter transit. The dust scattering recorded in these data provide an additional qualitative measure of plume activity on Io, indicating that the degree of dust scattering over Pele varied as a function of the date of observation, and that there were several other dust bearing plumes active during the observations. We present constraints on the composition and variability of the gas abundances of the Pele plume as well as the plumes detected by ACS and recorded within the STIS data, as a function of time.  相似文献   

Particle clusters in gravel‐bed rivers: an experimental morphological approach to bed material transport and stability concepts     

Lea Wittenberg  Malcolm D. Newson 《地球表面变化过程与地形》2005,30(11):1351-1368

Structured gravel river beds clearly exert a major influence on bed stability. Indexing structural stability by field measurements of bed strength neglects the processes operating to entrain and transport bed material in different parts of each structure. This study takes a morphological approach to interpreting the critical processes, using particle tracing to determine the movement of individual cluster particles over a range of flood event magnitudes and durations. The experiment was carried out on the River South Tyne, UK; it uses flow hydrographs measured nearby and also benefits from previous studies of historical development, channel morphology and sediment transport at the same site. More than 30 clusters were monitored over a seven‐month period during which clusters occupied 7–16 per cent of the bed. Threshold flows delimiting three apparently contrasting bed sediment process regimes for cluster particles are tentatively set at 100 m³ s^?1 and 183 m³ s^?1; durations of flow at these levels are critical for cluster development, rather than flow peak values. Wake particles are transported most easily. Flow straightening in the wandering channel planform reduces the stability of clusters, since mechanical strength is markedly reduced by this change of direction. The overall area covered by clusters between significant transport events varies little, implying a dynamic equilibrium condition. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

Hornblende Ar/Ar geochronology across terrane boundaries in the Sveconorwegian Province of S. Norway     

Bernard Bingen  Ariel Boven  Lea Punzalan  Jan R. Wijbrans  Daniel Demaiffe 《Precambrian Research》1998,90(3-4)

Hornblende incremental heating ⁴⁰Ar/³⁹Ar data were obtained from augen gneiss and amphibolite of the Sveconorwegian Province of S. Norway. In the Rogaland-Vest Agder and Telemark terranes, four pyroxene-rich samples, located close (≤ 10 km) to the anorthosite-charnockite Rogaland Igneous Complex, define an age group at 916 + 12/ − 14 Ma and six samples distributed in the two terranes yield another group at 871 + 8/ − 10 Ma. The first age group is close to the reported zircon U---Pb intrusion age of the igneous complex (931 ± 2 Ma) and the regional titanite U---Pb age (918 ± 2 Ma), whereas the second group overlaps reported regional mineral Rb---Sr ages (895-853 Ma) as well as biotite K---Ar ages (878-853 Ma). In the first group, the comparatively dry parageneses of low-P thermal metamorphism (M2) associated with the intrusion of the igneous complex are well developed, and hornblende ⁴⁰Ar/³⁹Ar ages probably record a drop in temperature shortly after this phase. In other hornblende + biotite-rich samples, with presumably a higher fluid content, the hornblende ages are probably a response to hornblende-fluid interaction during a late Sveconorwegian metamorphic or hydrothermal event. A ca 220 m.y. diachronism in hornblende ⁴⁰Ar/³⁹Ar ages is documented between S. Telemark (ca 870 Ma) and Bamble (ca 1090 Ma). Differential uplift between these terranes was mostly accommodated by shearing along the Kristiansand-Porsgrunn shear zone. The final stage of extension along this zone occurred after intrusion of the Herefoss post-kinematic granite at 926 ± 8 Ma. On the contrary, the southern part of the Rogaland-Vest Agder and Telemark terranes share a common cooling evolution as mineral ages are similar on both sides of the Mandal-Ustaoset Line the tectonic zone between them. The succession within 20 m.y. of a voluminous pulse of post-tectonic magmatism at 0.93 Ga, a phase of high-T-low-P metamorphism at 0.93-0.92 Ga, and fast cooling at a regional scale ca 0.92 Ga, suggests that the southern parts of Rogaland-Vest Agder and Telemark were affected by an event of post-thickening extension collapse at that time. This event is not recorded in Bamble.  相似文献   

Short-term changes in the magnitude, frequency and temporal distribution of floods in the Eastern Mediterranean region during the last 45 years — Nahal Oren, Mt. Carmel, Israel     

Lea Wittenberg  Haim Kutiel  Noam Greenbaum  Moshe Inbar 《Geomorphology》2007,84(3-4):181

Short-term changes in Eastern Mediterranean precipitation affecting flow regime were documented in Nahal Oren, a 35 km² ephemeral stream in Mt. Carmel, a 500 m high mountain ridge located at the NW coast of Israel. The rainy winter of the Mediterranean type climate (Csa) in Mt. Carmel is characterized by average annual rainfall of 550 mm at the coastal plain to 750 mm at the highest elevation while the summer is hot and dry. Stream flow generates after accumulated rainfall of 120–150 mm while “large floods”, defined as flows with peak discharge of > 5 m³ s^− 1 and/or > 150,000 m³ in volume, are generated in response to rainfall of over 100 mm. Hence, large floods in Nahal Oren stream occur not earlier than December. Precipitation and flow data were divided into two sub-periods: 1957–1969 and 1991–2003 and compared to each other. The results indicate a clear increase in the frequency of large floods, their magnitudes and volumes during the second period with no parallel change in the annual precipitation. Similarly, an increase in storm rainfall–runoff ratio from < 5% to > 15% and a decrease in the threshold rainfall for channel flow by 16–25% were documented. These short-term variations in flooding behavior are explained by the clear decrease in the length of the rainy season and by the resulting significant shortening in the duration of the dry-spells. The increase in the number of large rainfall events and the large floods in each hydrological year together with the increasing number of years with no floods indicate strengthening of their uncertainty of behavior.  相似文献   

Nutrient inputs from submarine groundwater discharge on the Santiago reef flat, Bolinao, Northwestern Philippines     

Senal MI  Jacinto GS  San Diego-McGlone ML  Siringan F  Zamora P  Soria L  Cardenas MB  Villanoy C  Cabrera O 《Marine pollution bulletin》2011,63(5-12):195-200

Submarine groundwater discharge (SGD) on the reef flat of Bolinao, Pangasinan (Philippines) was mapped using electrical resistivity, 222Rn, and nutrient concentration measurements. Nitrate levels as high as 126 μM, or 1-2 orders of magnitude higher than ambient concentrations, were measured in some areas of the reef flat. Nutrient fluxes were higher during the wet season (May-October) than the dry season (November-April). Dissolved inorganic nitrogen (DIN=NO3+NO2+NH4) and soluble reactive phosphorus (SRP) fluxes during the wet season were 4.4 and 0.2 mmoles m(-2) d(-1), respectively. With the increase population size and anthropogenic activities in Bolinao, an enhancement of SGD-derived nitrogen levels is likely. This could lead to eutrophic conditions in the otherwise oligotrophic waters surrounding the Santiago reef flat.  相似文献   

The Kinect: a low‐cost,high‐resolution,short‐range 3D camera     

Kenneth David Mankoff  Tess Alethea Russo 《地球表面变化过程与地形》2013,38(9):926-936

We present a novel application of the Kinect?, an input device designed for the Microsoft® Xbox 360® video game system. The device can be used by Earth scientists as a low‐cost, high‐resolution, short‐range 3D/4D camera imaging system producing data similar to a terrestrial light detection and ranging (LiDAR) sensor. The Kinect contains a structured light emitter, an infrared camera (the combination of these two produce a distance image), a visual wavelength camera, a three‐axis accelerometer, and four microphones. The cost is ~ US $100, frame rate is 30 Hz, spatial and depth resolutions are mm to cm depending on range, and the optimal operating range is 0.5 to ~5 m. The resolution of the distance measurements decreases with distance and is ≤1 mm at 0.5 m and ~75 mm at 5 m. We illustrate data collection and basic data analysis routines in three experiments designed to demonstrate the breadth and utility of this new sensor in domains of glaciology, stream bathymetry, and geomorphology, although the device is applicable to a number of other Earth science fields. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Mosquitoes in the mix: How transferable is creative city thinking?     

Susan Luckman  Chris Gibson  Tess Lea 《Singapore journal of tropical geography》2009,30(1):70-85

This paper contributes to recent debates about whether urban policy discourses are transferable and what is at stake in their translation. It draws on discussion of Darwin (Northwest Territory, Australia), a tropical savanna location that the local government wants to promote as a 'creative city', without quite knowing what this might require. We discuss relevant debates on research knowledge construction, the creative city and the path-dependent character of neoliberal governmental objectives. We then turn to the geographical, demographic and cultural characteristics that make Darwin a challenging and distinct context for translation of global theories of creative city rejuvenation. As well as arguing a case for more nuanced, locationally specific, analysis of the capacity of places to embrace travelling policy discourses, we suggest ways in which creative city research can be refreshed through engaging with literatures on (post)colonial urban politics and intersections with policy initiatives other than those targeted at 'creative industries' per se . We systematically outline the particular challenges that tropical cities in remote locations provide to accepted wisdom about creativity-led urban planning.  相似文献