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191.
Seaports are located in vulnerable areas to climate change impacts: on coasts susceptible to sea-level rise and storms or at mouths of rivers susceptible to flooding. They serve a vital function within the local, regional, and global economy. Their locations in the heart of sensitive estuarine environments make it an imperative to minimize the impacts of natural hazards. Climate impacts, like a projected SLR of .6?m to 2?m and doubling of Category 4 and 5 hurricanes by 2100, will result in more extreme events at many seaports. To assess the current state of knowledge on this issue, we surveyed port authorities from around the world about how administrators felt climate change might impact their operations, what sea-level change would create operational problems, and how they planned to adapt to new environmental conditions. The planned rapid expansion of ports reported by the survey respondents indicates that adaptation measures should be considered as ports construct new infrastructure that may still be in use at the end of the century. Respondents agreed that the ports community needs to address this issue and most felt relatively uninformed about potential climate impacts. Although most ports felt that SLR would not be an issue at their port this century, sea-level rise was nevertheless an issue of great concern. Our results suggest opportunities for the scientific community to engage with port practitioners to prepare proactively for climate change impacts on this sector. 相似文献
192.
S. Yonemura S. Kawashima H. Matsueda Y. Sawa S. Inoue H. Tanimoto 《Theoretical and Applied Climatology》2008,92(1-2):47-58
Summary The application of principal components and cluster analysis to vertical ozone concentration profiles in Tsukuba, Japan, has
been explored. Average monthly profiles and profiles of the ratio between standard deviation and the absolute ozone concentration
(SDPR) of 1 km data were calculated from the original ozone concentration data. Mean (first) and gradient (second) components
explained more than 80% of the variation in both the 0–6 km tropospheric and 11–20 km troposphere–stratosphere (interspheric)
layers. The principal components analysis not only reproduced the expected inverse relationship between mean ozone concentration
and tropopause height (r
2 = 0.41) and that in the tropospheric layer this is larger in spring and summer, but also yielded new information as follows.
The larger gradient component score in summer for the interspheric layer points to the seasonal variation of the troposphere–stratosphere
exchange. The minimum SDPR was at about 3 km in the tropospheric layer and the maximum was at about 17 km in the interspheric
layer. The tropospheric SDPR mean component score was larger in summer, possibly reflecting the mixing of Pacific maritime
air masses with urban air masses. The cluster analysis of the monthly ozone profiles for the 1970s and 2000s revealed different
patterns for winter and summer. The month of May was part of the winter pattern in the 1970s but part of the summer pattern
during the 2000s. This statistically detected change likely reflects the influence of global warming. Thus, these two statistical
analysis techniques can be powerful tools for identifying features of ozone concentration profiles.
Authors’ addresses: S. Yonemura, S. Kawashima, S. Inoue, National Institute for Agro-Environmental Sciences, 3-1-3 Kannondai,
Tsukuba, Ibaraki 305-0031, Japan; H. Matsueda, Y. Sawa, Meteorological Research Institute, 1-1 Nagamine, Tsukuba, Ibaraki
305-0052, Japan; H. Tanimoto, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan. 相似文献
193.
Takeshi Inoue 《Celestial Mechanics and Dynamical Astronomy》1984,34(1-4):185-191
The convergence property is examined for the series which appear in the theory of the planetary motions. With another point of view, we obtain a result different from that already given by Gyldén: The almost divergency in the meaning of category is concluded when the ratio of the mean motions is irrational using as Gyldén the continuous fractions. The author explains the reason why the series are always useful in practical applications: Because the long evolution of the system of interest under the influence of the small irreversible effects has led to many resonances or quasi-resonances, i.e. conditions favorable to a good convergence of suitable series. 相似文献
194.
Norio Kaifu 《Astrophysics and Space Science》1989,160(1-2):27-29
The current achievements of the observational abilities of radio astronomy is briefly reviewed putting emphasis on the imaging capability. The new projects in radio astronomy are discussed in connection with the new generation of optical/IR telescope projects.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 1988. 相似文献
195.
Vertical distributions of phyllosoma larvae were examined in waters east of the Philippines or west of the Mariana Islands
(18°56′ N to 19°04′ N; 129°10′ E to 129°35′ E) based on zooplankton samples collected with an Isaacs-Kidd Midwater Trawl on
September 22–24, 1986. Phyllosoma larvae belonged to the two families Scyllaridae and Palinuridae comprising 4 genera and
9 species. Of the collected phyllosoma larvae, those of Scyllarus cultrifer and Panulirus longipes were most abundant and showed similar vertical distributions: (1) both species were collected from the mixed layer at night
but not in the day, (2) their vertical distributions did not change with their stages, and (3) the upper limit of their vertical
distributions during the day accorded with the base of mixed layer. Furthermore, their vertical distributions were similar
to those of lepthocephalus larvae which were collected using the same sampling stations and gear in the present study. Vertical
distributions of phyllosoma larvae were discussed in relation to their horizontal distributions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
196.
Norio Ogura Yoshiharu Tanaka Jun-ichi Itoh Katsufumi Takahashi 《Journal of Oceanography》1984,40(3):184-191
Behaviour of dissolved and particulate proteinaceous substances in the estuary of the Tama River was investigated through field observations and laboratory experiments. Concentrations of dissolved proteinaceous substances in estuarine water were determined at eight stations between the mouth of the Tama River (TA-15) and a point 16km upstream (TA-8), using the colorimetric method of Lowryet al. (1951) that employs Folin phenol reagent. The results were expressed in terms of Folin phenol active substances (FPAS). It was found that FPAS decreased with increasing salinity and that the proportion of high molecular weight FPAS (molecular weight greater than 100,000) decreased rapidly in the estuary.The shapes, sizes and numbers of amorphous particulate substances stained by Amido Black 10B, called Amido Black active substances (ABAS), were determined under a microscope. The numbers of ABAS retained on Millipore HA filters (mean diameter: 10–80µm) amounted to 450ml–1 in the estuarine water about 6km from the mouth of the estuary (Station TA-12M). Some of these aggregates are considered to be producedin situ by flocculation of high molecular weight FPAS during estuarine mixing. ABAS were also produced in experiments by mixing filtered river water with sea water. 相似文献
197.
Since April 1986, measurements of the CO2 concentration in the surface air have been conducted at the Meteorological Research Institure (MRI, 36°04 N, 140°07 E, 25 m above sea level) in Tsukuba, located 50 km northeast of Tokyo, Japan. The CO2 data measured over times between 11:00 Japan Standard Time (JST) and 16:00 JST (C
N
) were considered to be representative of the air (within a few ppmv) in the planetary boundary layer. To evaluate the representative CO2 level on a spatial scale larger than that of the C
N
record, the CO2 data with hour-to-hour variation less than 1 ppmv were selected (C
P
). Comparison of these data with those of Ryori (39°02 N, 141°50 E), a continental station operated by the Japan Meteorological Agency, indicates that the C
P
record provides a representative CO2 level in the air on spatial scales of at least a few hundred kilometers.The C
N
record allows an investigation of the internanual changes in photosynthesis/respiration against changes in climatological parameters. Within a small temperature anomaly (ca.±1 °C) respiration is sensitive to the temperature change, while photosynthesis is less sensitive. When the temperature anomaly is large, however, photosynthesis and respiration tend to be competitive. 相似文献
198.
Masaaki Okuda Hiroomi Nakazato Norio Miyoshi Takeshi Nakagawa Hiroko Okazaki Saneatsu Saito Asahiko Taira 《Island Arc》2006,15(3):338-354
Abstract The 250-m Choshi core (CHOSHI-1), drilled from hemipelagic muds of the Inubo Group, has been physically, geochemically and tephrochronologically analyzed back to 1 Ma. We provide pollen results for the 19–169 m section of the core (400–780 ka) bracketed by the marker tephra Ty1 (equivalent to J4) and the Brunhes–Matuyama paleomagnetic boundary. The results show good agreement with the corresponding oxygen isotope (δ18 O) profile, with high δ18 O intervals dominated by boreal conifers Picea , Abies , Pinus (subgen. Haploxylon ) and Tsuga ( diversifolia ), whereas low δ18 O intervals are dominated by temperate conifers Cryptomeria , Taxaceae-Cephalotaxaceae-Cupressaceae and Sciadopitys . In order to confirm pollen-climate relations for the relevant taxa, a modern surface pollen dataset for the Japanese archipelago was consulted. In this analysis, the ratios of Cryptomeria / Picea and temperate/boreal conifers serve as proxies for the 100-kyr glacial/interglacial cycle during the Middle Pleistocene. Distinct signals for marine isotope stages (MIS) 11, 12, 13–15, 16, 17 and 18–19 are recognized in accordance with the tephrochronology and δ18 O of the same core. Application of the criteria to an independent pollen record from Lake Biwa provides an integrated pollen stratigraphy for mid-latitude Japan during the past 800 ky. Some degree of uncertainty remains in the chronology of the MIS13–15 interval, relating to the uncertainty in the eruption age of widespread tephra Ks11. 相似文献
199.
Physicochemical, mineralogical, and geochemical characteristics of 279 highly calcareous lacustrine sediment samples obtained from a 30 m drilling core in the western part of the Great Konya Basin, Turkey were studied. The sediments have a predominance of silt and clay fractions with a median diameter of 3–5 μm. Vertical changes of the amounts of water soluble components, gypsum, carbonates, and non-salt minerals such as quartz, feldspars, and layer silicates in the sediments suggest that there were climatic changes in the Konya Basin. The dominant clay mineral is smectite followed by kaolinite, illite, and palygorskite. The oxygen isotopic (δ18O) ratios of six quartz samples from the Konya sediments, a terra rossa soil beside Lake Bey
ehir gölü and paleosols at the foot of Mt. Erciyes Da
ranged from +18.1 to +20.6‰. The dominant clay minerals and δ18O ratios suggest that part of quartz and coexisting layer silicates is of long-range transported and/or local aeolian dust origin from arid and semi-arid regions such as North Africa, Israel, and the surroundings. The relatively high deposition rate might be due to aeolian dust input and/or the sediment input introduced by the rivers such as the Çar
amba river from the Toros (Taurus) mountains. The vertical distributions of electro-conductivity, amounts of water soluble and non-salt components, and the gypsum content of the sediments suggest that gypsum-rich layers were formed under shallow, saline waters, possibly associated with warm to hot and dry environments such as the Last Interglacial epoch and the Early Holocene. The sediments characterized by relatively high amounts of non-salt sediments, in which gypsum did not accumulate, could be deeper water phases formed under the cold and/or wet environments such as the Glacial epochs. 相似文献
200.
To find out the secular and seasonal trends of the 13C value and CO2 concentration in the surface air and the determination of the 13C in the atmospheric CO2 collected at Tsukuba Science City was carried out during the period from July 1981 to October 1983. The monthly average of the 13C value of CO2 in the surface air collected at 1400 LMT ranged from -7.52 to \s-8.45 with an average of -7.96±0.25 and the CO2 concentration in the air varied from 334.5 l 1-1 to 359 l 1-1 with an average of 347.2±6.3 l 1-1. The 13C value is high in summer and low in winter and is negatively correlated with the CO2 concentration. In general, the relationship between the 13C and the CO2 concentration is explainable by a simple mixing model of two different constant carbon isotopic species but the relationship does not always follow the model. The correlation between the 13C value and the CO2 concentration is low during the plant growth season and high at other times. The observed negative deviation of the 13C value from the simple mixing model in the plant growth season is partly due to the isotopic fractionation process which takes place in the land biota. 相似文献