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61.
In a program conducted to isolate AGK3 stars with large proper motions, it has been found that more than one hundred stars seem to be affected by large errors in their published proper motions. For some of those objects south of +25 degrees, new proper motions are being obtained using, as first-epoch positions, the published material of the Astrographic Catalogue. Second-epoch positions are derived from new plates taken with the Yale Southern Observatory double astrograph.  相似文献   
62.
In absence of other mechanisms, the main input of CO2into the Venusian atmosphere is via volcanic out gassing. Since Venus can be regarded as a planet-wide large igneous province, we can expect large quantities of CO2 being transferred into its atmosphere via volcanic out gassing. We have quantified the maximum possible amount of CO2 that can be out gassed via a single massive episode of resurfacing of the planet. This figure (5.6 × 1019 kg of CO2) is about 8 times smaller than the total CO2 present in the Venusian atmosphere (4.55 × 1020 kg CO2). The lack of planet-wide, efficient mechanisms for the recycling of CO2 on Venus indicates that CO2 has progressively accumulated in the atmosphere. Based on these considerations we suggest that the “equivalent” to eight global resurfacing episodes would be required to account for the present values of CO2 atmosphere. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
63.
The (J, K)=(1,1) ammonia transition emission has been observed toward six regions with signs of active star formation (AFGL 5142, HH 33/40, AFGL 5157, AFGL 6366S, HHL 73, and S140N), using the 37 m antenna of the Haystack Observatory. We detected and mapped the ammonia emission in all of these sources with the exception of HH 33/40. The (J, K)-(2,2), ammonia transition was also observed at the peak position of each source in order to obtain the rotational temperature of the ammonia clumps.Paper presented at the 11th European regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.  相似文献   
64.
 Functional group analysis was used to determine the major bioturbators in the Dry Tortugas, Florida Keys. The surface community is dominated by surface deposit feeding polychaetes and burrowing bivalves capable of mixing the top 0–4 cm of the sediment on time scales of days to weeks. Bioturbation by the Notomastus sp. and Callianassa sp. deep community effectively removes primary sedimentary structures. Their fossilized burrow structures may be geologically important in this system. Surface microtopography is controlled by stabilizing and destabilizing forces that determine the potential for surface resuspension and sediment transport in the Dry Tortugas.  相似文献   
65.
66.
A principal challenge in developing any fishery management plan is the allocation of benefits and costs among participants in the fishery. This process is further complicated by imperfect information about future market demand and limited ability to predict the consequences of regulatory change. This paper offers a new approach to policymakers, using econometric analysis to simulate the potential impact of individual tradable quotas (ITQs) in a fishery. We compare the distribution of harvest across participants in the Atlantic Herring fishery under the current open access regime and under a potential ITQ regime, assuming two different levels of future demand. Our results show that production efficiency varies by vessel gear, home-port and relationship with buyers. Some of the predicted consequences of ITQs are: vessels from Massachusetts will gain share relative to those from Maine; trawlers will gain share relative to purse seine vessels; and independent vessels will lose share relative to vessels that are primarily contracted to specific processors or bait companies. These results will help policymakers in developing future management plans for the herring fishery. More generally, this analytical approach can help regulators in any fishery assess the potential impact of alternative policy changes under alternative future demand scenarios.  相似文献   
67.
The ‘forgotten fjords’ and ‘deserted inlets’ of NE‐Iceland, in the region between Borgarfjörður Eystri and Loðmundarfjörður, are not only prominent because of their pristine landscape, their alleged elfin settlements, and the puffins that breed in the harbour, but also for their magnificent geology. From a geological point of view, the area may hold Iceland's best kept geological secret. The greater Borgarfjörður Eystri area hosts mountain chains that consist of voluminous and colourful silicic rocks that are concentrated within a surprisingly small area (Fig. 1 ), and that represent the second‐most voluminous occurrence of silicic rocks in the whole of Iceland. In particular, the presence of unusually large volumes of ignimbrite sheets documents extremely violent eruptions during the Neogene, which is atypical for this geotectonic setting. As a group of geoscientists from Uppsala University (Sweden) and the Nordic Volcanological Center (NordVulk, Iceland) we set out to explore this remote place, with the aim of collecting material that may allow us to unravel the petrogenesis of these large volumes of silicic rocks. This effort could provide an answer to a long‐standing petrological dilemma; the question of how silicic continental crust is initially created. Here we document on our geological journey, our field strategy, and describe our field work in the remote valleys of NE‐Iceland.  相似文献   
68.
At three sites along the North Norfolk coast, freshwater sediments containing arctic plants have been reported to occur immediately beneath the glacial deposits. The sections at Mundesley and Beeston are no longer visible but a small exposure of this ‘Arctic Fresh-water Bed’ has recently been rediscovered at Ostend near Bacton. The fossils from this deposit are distinctly high boreal/arctic in character, indicating a small, possibly ephemeral, pool in a generally open landscape supporting some dwarf shrubs and conifers. Noteworthy records include three beetle species (Pterostichus brevicornis, P. middendorffi and Helophorus obscurellus) that today have their closest occurrences on either the Kanin or Kola peninsulas in arctic Russia. A Mutual Climatic Range reconstruction on the limited beetle fauna suggests that the mean temperatures of the warmest and coldest months were between 9 °C and 11 °C and between −36 °C and −10 °C, respectively. Other noteworthy occurrences include the aquatic pulmonate gastropod Gyraulus rossmaessleri (second and earliest British record), the ostracod Amplocypris tonnensis (earliest British record), ground squirrel (Spermophilus sp.) and the first record of arctic lemming (Dicrostonyx sp.) from the Cromer Forest-bed Formation (CF-bF). The ‘Arctic Fresh-water Bed’ has been assigned to the Bacton Member of the CF-bF and formed during the early Anglian, correlated with Marine Isotope Stage (MIS) 12 of the deep sea record. The Ostend assemblage is therefore important in providing a glimpse of conditions that occurred during a major cold stage in the early Middle Pleistocene.  相似文献   
69.
The arsenic content of geothermal hot springs and their sediments in the north-central Andean region of Ecuador has been investigated. The area of study is located between parallels 1°11′N and 1°30′S and includes five provinces. The area is rich in geothermal surface manifestations that are mainly used for medicinal baths in recreational complexes. Unfortunately, water residuals without treatment are released from the recreational facilities to surrounding water bodies. The results indicate that total arsenic in geothermal waters in this region has a range of 2–969 μg As/L, and sediments contain arsenic ranging from 1.6 to 717.6 mg/kg. Chemical analyses of sediment samples show the presence of sulfur, iron, aluminum and calcium. A high concentration of natural organic matter was also found in some samples (20–29.5%); thus sorption and coprecipitation can be the main mechanisms of As immobilization on mineral phases and natural organic matter.  相似文献   
70.
The way that the media reports and comments on key events in the fragmented global climate governance landscape is one important route to strengthening public accountability of such governance. Editorials and other opinion pieces provide key contributions to the public sphere, but have been almost entirely neglected in media research on climate change. Another understudied aspect in such research is the reporting on the fragmentation of global climate governance across numerous forums. This article provides an exploratory approach to address these two research gaps. It presents a quantitative analysis of how often leading newspapers in seven countries (Finland, India, Laos, Norway, South Africa, UK and USA) wrote about 18 meetings in six different global climate governance forums between 2004–2009 and whether they provided commentaries about them. The study shows that media coverage (articles and opinion pieces) is limited or absent for many meetings that are not attended by heads of state, are the launch of a new process or do not have the convening power of the United Nations Framework Convention on Climate Change. The pattern of coverage differs significantly among individual newspapers and there is no clear distinction between developed and developing country newspapers. The article concludes that overall news coverage, and editorial commentary in particular, of global climate meetings in the selected newspapers is too low and too patchy to significantly support domestic publics to hold their own (and indirectly other) governments accountable with regard to fragmented global climate governance.

Policy relevance

This study is instructive for the media and civil society, who should both act as accountholders of governments with regard to how they act in global climate governance and its implementation. Reporting and commentaries need to reflect the overarching process, not only sporadic coverage of high-level meetings, but also critical analysis of what is achieved. They should also take a broader scope in terms of the kinds of meetings and processes in global governance that they cover. Civil society should encourage the media to increase coverage along these lines, e.g. by adequate monitoring of government actions (or lack thereof) and share this with the media.  相似文献   
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