Photometric redshift accuracy in AKARI deep surveys     

M. Negrello  S. Serjeant  C. Pearson †  T. Takagi  A. Efstathiou  T. Goto  D. Burgarella  W.-S. Jeong  M. Im  H. M. Lee  H. Matsuhara  S. Oyabu  T. Wada  G. White 《Monthly notices of the Royal Astronomical Society》2009,394(1):375-397

  相似文献   

Relationship between growth of albite porphyroblasts and deformation in a sambagawa schist, Central Shikoku, Japan     

Kiyoshi Takagi  Ikuo Hara 《Tectonophysics》1979,58(1-2)

Albite porphyroblasts in a basic schist of the Sambagawa metamorphic belt (Besshi—Bashi, Central Shikoku) show zonal variation of inclusions defined by inclusion-free mantles and inclusion-rich cores, though matrix minerals are partly incorporated in the outer zones of the mantles. From comparison of the crystallographic and dimensional fabrics of inclusion and matrix epidote, it has been concluded that the orientation of the principal axes of strain was different for the deformation of matrix fabrics and inclusion fabrics (fabrics produced before formation of cores). Inclusion amphibole in the cores belongs to the actinolite—common hornblende group, with Si content more than 7.0, whereas amphibole in the matrix and outer zones of mantles belongs to the common hornblende group, with Si content less than 7.1. This shows that the metamorphic temperature was higher during the phase of formation of the outer zones of the mantles than during that of the cores. The average direction of maximum growth of the mantles, which has been estimated from differences between the average shapes of porphyroblasts and those of cores, is parallel to the linear orientation of amphibole and epidote in the matrix. The average direction of minimum growth of the mantles coincides with the normal to the schistosity of the matrix. The mantles appear to be of the same generation as the matrix fabrics.  相似文献   

Stratospheric aerosol inferred from electrical conductivity during a volcanically quiescent period     

Y. Kondo  R. Reiter  H. Jäger  M. Takagi 《Pure and Applied Geophysics》1982,120(1):1-10

Profiles of electrical conductivity in the troposphere and stratosphere were measured by balloon-borne conductivity sondes at Garmisch-Partenkirchen, West Germany, from January to May, 1980, when volcanic activity was low. The aerosol concentration has been deduced from the relative decrease of conductivity from surrounding values by assuming the effective attachment coefficient of ions to aerosols. A prominent decrease of the conductivity near the tropopause is usually observed indicating high concentrations of Aitken particles (500–1000 cm^–3). A decrease of conductivity, well above the tropopause, is sometimes observed, probably due to the transport of tropospheric Aitken particles with high concentration (200–400 cm^–3) into the stratosphere.  相似文献   

Tsunami awareness: a comparative assessment between Japan and the USA     

Miguel Esteban  Jeremy Bricker  Ricardo San Carlos Arce  Hiroshi Takagi  NamYi Yun  Warathida Chaiyapa  Alexander Sjoegren  Tomoya Shibayama 《Natural Hazards》2018,93(3):1507-1528

Awareness about the threats posed by different types of coastal disasters has increased throughout the world, as people are exposed to the nature of these hazards through media reports on events in distant countries. This has resulted in coastal residents being aware about the destructive power of tsunamis, despite no such events having taken place in their country in recent times. Regardless of this increased awareness, it has been hypothesized that there is still need for local governments to enact adequate policies to raise the awareness of local residents, for example, by holding regular evacuation drills. The present research presents a comparative assessment of tsunami awareness in two tourist destinations in Japan and the USA, which was derived through structured questionnaire surveys of beach users in the city of Kamakura and various coastal cities in Florida. The results show how despite relatively high level of awareness tsunamis still pose a considerable risk to each of the communities, for example, due to shortcoming in evacuation knowledge and infrastructure.  相似文献   

Arsenic species and their accumulation features in green turtles (Chelonia mydas)     

Agusa T  Takagi K  Iwata H  Tanabe S 《Marine pollution bulletin》2008,57(6-12):782-789

Total arsenic (As) and its compounds were determined in liver, kidney, muscle, and stomach contents of green turtles (Chelonia mydas). Total As concentrations in the muscle were higher than those in the kidney and liver. Arsenobetaine (AB) was the predominant compound in all the three tissues and its levels were positively correlated with total As concentrations. This indicates that AB greatly contributes to As accumulation in green turtles. Higher concentrations of remaining As in the sample after extraction were detected in the liver, implying that lipid-soluble or protein bound As compounds accumulate in the liver of green turtles. Total As levels in tissues showed significant negative correlations with standard carapace length. The size-dependence of As accumulation in green turtles may be related to their feeding habit, shifting from carnivore to herbivore at different growth stages. Concentrations of AB and dimethylarsinic acid (DMA) were low in the stomach contents but high in the tissues, implying bioaccumulation of these arsenicals in green turtles.  相似文献   

Classification of Tsunami and Evacuation Areas   总被引：3，自引：2，他引：1  

Tomoya Shibayama  Miguel Esteban  Ioan Nistor  Hiroshi Takagi  Nguyen Danh Thao  Ryo Matsumaru  Takahito Mikami  Rafael Aranguiz  Ravindra Jayaratne  Koichiro Ohira 《Natural Hazards》2013,67(2):365-386

On March 11, 2011, a large earthquake that occurred offshore the north-east coast of Japan generated a large tsunami which devastated extensive areas of the Tohoku coastline. Despite Japan being considered a country well prepared for these types of disasters, large casualties were recorded, with numerous discussions amongst the Japanese coastal engineering community ensuing. As a result, two different levels of tsunamis have been proposed and now recognized in Japan, depending on the frequency of such extreme events. The idea that hard measures can protect the lives of inhabitants of coastal areas has been abandoned, and these measures are only considered to be effective in protecting properties against the more frequent but lower magnitude events. Soft measures should always be used to protect against the loss of lives, and to this respect, the authors of the paper propose the introduction of a Classification of Evacuation Areas, to show which of these should be prioritized by residents as they seek to evacuate.  相似文献   

Impact of mesoscale eddies on particulate organic carbon flux in the western subarctic North Pacific     

Dobashi  Ryo  Ueno  Hiromichi  Matsudera  Nozomi  Fujita  Isao  Fujiki  Tetsuichi  Honda  Makio C.  Harada  Naomi 《Journal of Oceanography》2022,78(1):1-14

The mechanism that controls particulate organic carbon (POC) flux in the deep sea differs depending on the season and sea. The POC produced in the western subarctic North Pacific are known to be transported to the deep sea efficiently, but the direct relationship between the POC flux and physical processes is still unclear. In this study, we evaluated the effect of mesoscale eddies on POC flux in the western subarctic North Pacific. The seasonal and interannual variabilities of POC flux were investigated using data from a time-series sediment trap deployed at 4810 m at station K2 (47°N, 160°E) from 2005 to 2018. POC flux was high during May–November, appearing to reflect spring and fall blooms at the ocean surface. POC flux also showed interannual variability, with twelve peaks that were mostly affected by enhanced bloom just before the peak. Nine peaks of the twelve peaks were affected by mesoscale eddies, which enhanced bloom around K2 by extending the area with a high chlorophyll-a concentration along the coastal region into the offshore region, suggesting that mesoscale eddies strongly impact the interannual variability of POC flux at K2.

  相似文献   

Wet surface resistance of forest canopy in monsoon Asia: Implications for eddy‐covariance measurement of evapotranspiration          下载免费PDF全文

J. Hong  K. Takagi  T. Ohta  Y. Kodama 《水文研究》2014,28(1):37-42

During the Asian monsoon period, intense precipitation commonly occurs for an extended period in accompaniment with a reduction in solar radiation. This suggests that wet surface evapotranspiration is an important contributor to the total evapotranspiration. Therefore, investigating evapotranspiration over a wet canopy surface is critical to achieve a better understanding of water and energy cycles in Asia. In this study, we estimated surface resistances under wet conditions in a mixed forest influenced by the East Asian monsoon system. We showed that the surface resistance had a non‐negligible magnitude of about 30 sm^?1 even under wet conditions. We also found that the ratio between the actual and potential evapotranspiration depended on the friction velocity regardless of the time of day. Our analyses suggest that this dependency is tightly related to the underestimation of turbulent fluxes by the eddy‐covariance system under wet surface conditions. Together, our findings suggest that the wet surface resistance, although small, should be considered in simulating evapotranspiration because the forest ecosystem is strongly coupled to the overlying atmosphere. This could significantly improve the shortcomings of evapotranspiration measurement and modeling in Asian forest canopies influenced by the monsoon system. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

Estimation of increase in storm surge damage due to climate change and sea level rise in the Greater Tokyo area     

Sayaka Hoshino  Miguel Esteban  Takahito Mikami  Hiroshi Takagi  Tomoya Shibayama 《Natural Hazards》2016,80(1):539-565

  相似文献   

POC fluxes estimated from 234Th in late spring–early summer in the western subarctic North Pacific     

Hajime Kawakami  Makio C. Honda  Kazuhiko Matsumoto  Masahide Wakita  Minoru Kitamura  Tetsuichi Fujiki  Shuichi Watanabe 《Journal of Oceanography》2015,71(3):311-324

  相似文献