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191.
Huasheng Hong Chen-Tung Arthur Chen Yuwu Jiang Jiann-Yuh Lou Zhaozhang Chen Jia Zhu 《Journal of Oceanography》2011,67(4):385-393
It is generally accepted that the flow is northward in the Taiwan Strait during summer and that the strongest current is detected
in the Penghu Channel between the Penghu Islands and the Taiwan Island. This current, the eastern prong flow, is made up of
waters from the South China Sea (SCS) and the Kuroshio. North of the Penghu Islands, the current veers to the west before
turning northward again because of the shallow Chang-Yuen Ridge, and extends westward off the coast of Taiwan. There is a
second prong of northward flow existing between the Taiwan Bank and the China mainland coast. Here, we show with observational
data as well as results from a numerical model that this water receives little influence from the Kuroshio and is distinctively
cooler, fresher, less oxygenated and more acidic, and contains more dissolved inorganic carbon than waters at the same density
level of the eastern prong. Evidence is provided to show that the source water of the western prong should be the subsurface
water from the strong upslope advection flowing northward from the SCS to the southern Taiwan Strait and upwelling along the
coast during the favorable southwesterly wind. Subsequently, the upwelled water flows over the saddle west of the Taiwan Bank
and joins the main flow northwest of the Penghu Islands. 相似文献
192.
David R. Easterling Henry F. Diaz Arthur V. Douglas William D. Hogg Kenneth E. Kunkel Jeffry C. Rogers Jaime F. Wilkinson 《Climatic change》1999,42(1):285-308
In this paper we discuss data available from Argentina, Mexico, the United States and Canada that are suitable for the analysis of extreme temperature and precipitation events. We also discuss some of the problems of homogeneity and quality control that can potentially affect the observation of extreme values. It is clear that even in countries like the United States and Canada that have a potentially rich source of climate data there are still problems in obtaining homogeneous data necessary to perform thorough studies of time varying changes in extreme events. These types of problems may be compounded if data are needed from countries that do not have a tradition of maintaining large climate archives or observing networks.We also provide two examples of analyses that can be performed with these types of data: (1) the development of climate extremes indices for Canada, and (2) analyses of freezing events for Florida and the effect on the citrus industry. The Canadian example provides a good basis for countries to take indices developed for one country or region and through minor modifications make the index relevant to their own needs. The analysis of freezing events in Florida is a timely example of how extreme events have both ecological and societal impact. 相似文献
193.
Pekka Heinämäki Harry J. Lehto Mauri J. Valtonen Arthur D. Chernin 《Monthly notices of the Royal Astronomical Society》1999,310(3):811-822
An ensemble of Newtonian three-body models with close initial separations is investigated by following the evolution of a 'drop' in the homology map. The onset of chaos is revealed by the motion and the complex temporal deformation of the drop. In the state of advanced chaos, the drop spreads over almost the whole homology map, quite independently of its initial position on the map. A general quantitative measure of this process is the mean exponential rate of spreading, which bears resemblance to Kolmogorov–Sinai entropy; this is introduced and estimated in terms of the homology mapping. In a similar manner we also estimate the mean exponential rate of divergence of initially close-by trajectories. This is a close analogue to the Lyapunov exponent. These parameters measure two complementary aspects of dynamical instability, which is the basic mechanism of the onset of chaos. 相似文献
194.
This note proposes a practical and economical alternative to using Kubiena boxes for the collection of undisturbed soil or sediment samples for micromorphological analysis. The authors promote the use of plastic electrical outlet boxes (gang boxes) that can be purchased at any hardware store for around 20 cents apiece. In addition to availability and low cost, plastic gang boxes are preferred by thin‐section laboratories over that of the aluminum Kubiena boxes because they cause less wear on the thin‐sectioning equipment. As with Kubiena boxes, the samples are impregnated directly in the gang boxes, yet they are more easily and efficiently retrieved, thus facilitating overall sample preparation and insuring a final product of equal or better quality. © 2003 Wiley Periodicals, Inc. 相似文献
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199.
Arthur Holcombe Ph.D. 《GeoJournal》1987,14(1):11-18
This paper gives the actual scenario of the national and international activities during the famine disaster in Dar Fur Region,
Sudan. The author gives the example of the Dar Fur Workshop to illustrate how international cooperation functions in such
cases. He deals with the conflicting objectives of relief measures on the one hand and medium-term and long-term development
objectives on the other. The author presents an insight into the work of foreign aid in the Sudan and the constraints with
which it is confronted. He intentionally leaves judgement for the reader to make.
The author was the Resident Representative of the United Nations Development Programme in the Sudan at the time the Dar Fur
Strategy for Rehabilitation and Development was being prepared. The views expressed are his own except where otherwise indicated. 相似文献
200.
Effect of anthropogenic CO2 on the pH and the saturation states of calcite and aragonite of seawater
Growth of phytoplankton, zooplankton and probably most other marine organisms as well, is likely to be affected by the pH
of seawater. Growth of calcareous shells and skeletons is less likely to be affected by the saturation states of calcite and
aragonite but the dissolution is.
The increase of CO2 in the oceans due to burning of fossil fuel and clearing of forests is decreasing the pH of seawater and the degrees of saturation
for calcite and aragonite wordwide. This paper presents the results of the first attempt to estimate the vertical distribution
of anthropogenic CO2, and the decreases in pH and the degrees of saturation of calcite and aragonite in seawater near Taiwan. Most effects are
very small except for the possible dissolution of aragonite on the upper continental slope starting around 2050 AD. 相似文献