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101.
Trevor C. Hall Andrea M. Sealy Tannecia S. Stephenson Shoji Kusunoki Michael A. Taylor A. Anthony Chen Akio Kitoh 《Theoretical and Applied Climatology》2013,113(1-2):271-287
Present-day (1979–2003) and future (2075–2099) simulations of mean and extreme rainfall and temperature are examined using data from the Meteorological Research Institute super-high-resolution atmospheric general circulation model. Analyses are performed over the 20-km model grid for (1) a main Caribbean basin, (2) sub-regional zones, and (3) specific Caribbean islands. Though the model’s topography underestimates heights over the eastern Caribbean, it captures well the present-day spatial and temporal variations of seasonal and annual climates. Temperature underestimations range from 0.1 °C to 2 °C with respect to the Japanese Reanalysis and the Climatic Research Unit datasets. The model also captures fairly well sub-regional scale variations in the rainfall climatology. End-of-century projections under the Intergovernmental Panel on Climate Change SRES A1B scenario indicate declines in rainfall amounts by 10–20 % for most of the Caribbean during the early (May–July) and late (August–October) rainy seasons relative to the 1979–2003 baselines. The early dry season (November–January) is also projected to get wetter in the far north and south Caribbean by approximately 10 %. The model also projects a warming of 2–3 °C over the Caribbean region. Analysis of future climate extremes indicate a 5–10 % decrease in the simple daily precipitation intensity but no significant change in the number of consecutive dry days for Cuba, Jamaica, southern Bahamas, and Haiti. There is also indication that the number of hot days and nights will significantly increase over the main Caribbean basin. 相似文献
102.
Tae-Soo Pyo Masahiko Hayashi Naoto Kobayashi Alan T. Tokunaga Hiroshi Terada Miwa Goto Takuya Yamashita Yoichi Itoh Hideki Takami Naruhisa Takato Yutaka Hayano Wolfgang Gaessler Yukiko Kamata Yosuke Minowa Masanori Iye 《Astrophysics and Space Science》2003,287(1-4):21-24
We present high angular resolution spectra taken along the jets from L1551 IRS 5 and DG Tau obtained with the Subaru Telescope. The position-velocity diagrams of the [Fe II] λ 1.644 μmemission line revealed remarkably similar characteristics for the two sources, showing two distinct velocity components separated from each other in both velocity and space with the entire emission range blueshifted with respect to the stellar velocity. The high velocity component (HVC) has a velocity of –200 ––300 km s-1 with a narrow line width, while the low velocity component (LVC) is around –100 km s-1 exhibitinig a broad line width. The HVC is located farther away from the origin and is more extended than the LVC. Our results suggest that the HVC is a well-collimated jet originating from the region close to the star, while the LVC is a widely-opened wind accelerated in the region near the inner edge of the accretion disk. 相似文献
103.
Characteristic time scales relevant to the accumulation of planetesimals in a gaseous nebula are examined and the accumulation toward the planets is simulated by numerically solving a growth equation for a mass distribution function. The eccentricity and inclination of planetesimals are assumed to be determined by a balance between excitation due to mutual gravitational scattering and dissipation due to gas drag. Two kinds of mass motion in the radial direction, i.e., diffusion due to mutual scattering and inward flow due to gas drag, are both taken into account. The diffusion is shown to be effective in later stages with a result of accelerating the accumulation. As to the coalescent collision cross section, the usual formula for a binary encounter in a free space is used but the effect of tidal disruption which increases substantially the cross section is taken into account. Numerical results show that the gravitational enhancement factor (i.e., the so-called “Safronov number”), contained in the cross section formula, always takes a value of the order of unity but the accumulation proceeds relatively rapidly owing to the effects of radial diffusion and tidal disruption. That is, a proto-Earth, a proto-Jupiter, and a proto-Saturn with masses of 1×1027 g are formed in 5×106, 1×107, and 1.6×108 years, respectively. Also, a tentative numerical computation for the Neptune formation shows that a proto-Neptune with the same mass requires a long accumulation time, 4.6×109 years. Finally, the other effects which are expected to reduce the above growth times further are discussed. 相似文献
104.
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106.
Shoji Kojima María Constanza San Martín Toshiro Nagase Daisuke Nakashima Claudio Bisso Andrew Menzies 《Resource Geology》2021,71(1):80-90
Modes of occurrence of Au‐ and Ag‐bearing phases and their relation with associated hypogene ore minerals were examined with the objective to elucidate Au‐Ag distribution at the Esperanza porphyry deposit in the Eocene Centinela copper belt, using ore‐microscope modal analysis, semi‐quantitative analyses by automated mineralogy, electron probe microanalysis, and secondary ion mass spectrometer. The Esperanza hypogene mineralization is characterized by early‐stage chalcopyrite‐rich veinlets in the potassic alteration zone and later polymetallic stage with tennantite and galena in the chlorite‐sericitic alteration zone. Only the early‐stage chalcopyrite contains fine‐grained electrum (Au68Ag32 ‐ Au81Ag19) and hessite (Ag2Te), and thus yields positive correlations in Cu vs. Au and Cu vs. Ag grades that are clearly recognized in the hypogene sulfide zone. The early‐stage chalcopyrite grains frequently exhibit polysynthetic twinning suggestive of inversion from intermediate solid solution. These features suggest that the fine‐grained electrum and hessite are products exsolved in the cooling process with the intermediate solid solution to chalcopyrite inversion. In contrast, tennantite and galena of the later‐stage mineralization contain no detectable Ag, and it is thus proposed that the early‐stage inverted chalcopyrite is the principal storage of economically important precious metals. 相似文献
107.
Morishita Tomoaki Ghosh Biswajit Soda Yusuke Mizukami Tomoyuki Tani Ken-ichiro Ishizuka Osamu Tamura Akihiro Komaru Chihiro Aari Shoji Yang Hsiao-Chin Chen Wen-Shan 《Mineralogy and Petrology》2018,112(4):521-534
Mineralogy and Petrology - We examine ultramafic and olivine-rich troctolite blocks of the East Taiwan Ophiolite (ETO) in the Lichi Mélange. Although ultramafic rocks are extensively... 相似文献
108.
Takahisa Furuichi Nobutomo Osanai Shin-ichiro Hayashi Norihiro Izumi Tomoko Kyuka Yasuhiro Shiono Tomoyoshi Miyazaki Tomoya Hayakawa Norihiro Nagano Naoki Matsuoka 《Landslides》2018,15(8):1645-1655
In August 2016, Typhoon 1610 (Lionrock) caused heavy rainfall in Hokkaido, which led to the discharge of a large volume of sediment and water from catchments on the eastern slope of the northern Hidaka Range. The eight catchments examined in this study are characterized by granitic lithology and late Pleistocene periglacial landforms with weakly cohesive, low-resistance periglacial debris thickly covering the weathered bedrocks. This characteristic of the landscape presumably provided a transport-limited condition where some debris flows were initiated by shallow landslides. As they moved, the debris flows grew larger through mobilization and erosion of sediment in channel beds and sidewalls. This sediment mobilization and erosion continued for an extensive distance along the course of the river. Morphological changes induced by channel aggradation and bank erosion were considerable and distinctive from upstream to downstream. Granitic periglacial sediments are amply present on the mountain slopes, river channels, and river banks in the area, likely due to the rarity of intensive rainfall events. These distinctive features of fossil periglacial catchments are important for disaster prevention and catchment-scale sediment management in sub-boreal areas, particularly in the context of climate change, which may generate more frequent and intensive rainfall events. 相似文献
109.
110.
We studied the morphological and biochemical changes of mitochondria-rich cells (MRCs) of a demersal teleost, Paralichthys olivaceus, during exposure to 0.98, 2.97 and 4.95 kPa pCO2. The apical opening area of MRCs increased 2.2 and 4.1 times by 24 h exposure to 2.97 and 4.95 kPa pCO2, respectively, while the cross-sectional area or density of MRCs did not change. Gill Na+/K+-ATPase activity more than doubled at 72 h and then returned to the pre-exposure level at 168 h in 0.98 kPa pCO2, while it increased 1.7 times at 24 h at 4.95 kPa. These results indicate that the apical opening area of MRCs and the gill Na+/K+-ATPase activity may be used as an indicator of acute (up to 72 h), but not chronic, impacts of high (>1 kPa) seawater CO2 conditions in P. olivacues. Limitations of those parameters as indices of CO2 impacts are discussed. 相似文献