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91.
黑龙江省是受气象灾害影响最严重的省份之一,最大限度地保护人民群众生命财产安全,对气象防灾减灾提出了更高要求。省委建设"八大经济区"、实施"十大工程"战略部署,对公共气象服务提出了更多需求。中央领导对黑龙江省粮食稳定增产寄予厚望,但近些年极端气候事件增多,粮食增产的基础还很不牢 相似文献
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The corals of the Persian/Arabian Gulf are better adapted to temperature fluctuations than elsewhere in the Indo-Pacific. The Gulf is an extreme marine environment displaying the highest known summer water temperatures for any reef area. The small and shallow sea can be considered a good analogue to future conditions for the rest of the world’s oceans under global warming. The fact that corals can persist in such a demanding environment indicates that they have been able to acclimatize and selectively adapt to elevated temperature. The implication being that colonies elsewhere may be able to follow suit. This in turn provides hope that corals may, given sufficient time, similarly adapt to survive even in an impoverished form, under conditions of acidification-driven lowering of CaCO3 saturation state, a further consequence of raised atmospheric CO2. This paper demonstrates, however, that the uniquely adapted corals of the Gulf may, within the next three centuries, be threatened by a chronic habitat shortage brought about by the dissolution of the lithified seabed on which they rely for colonisation. This will occur due to modifications in the chemical composition of the Gulf waters due to climate change. 相似文献
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亚马逊水下三角洲底部边界层的测量D.A.Cacchione等近底边界层为流体剪切为直接作用于悬浮物及底床表层沉积物以形成冲刷或沉积的地带.对水下三角洲生长及结构的动力过程的认识主要借助于分析近底边界层重要的物理及沉积参数来进行的.本文我们利用GEOP... 相似文献
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Jurassic Black Shales Facies from Qiangtang Basin (Northern Tibet):Rare Earth and Trace Elements for Paleoceanographic Implications 总被引:1,自引:0,他引:1
CHEN Lan YI Haisheng TSAI Louis Loung-Yie XU Guiwen DA Xuejuan LIN Andrew Tien-Shun 《《地质学报》英文版》2013,87(2):540-554
The Biluo Co and Amdo 114 station, northern Tibet, cropping out the Early Toarcian and Middle-Late Tithonian (Jurassic) organic-rich black shales, have been a focus to petroleum geologists in discussing their oil-producing potential. This paper first reports the trace elements and rare earth elements to discuss the paleoenvironments, redox conditions and sedimentary mechanisms of those black shales. Both sections exhibit variation in trace element abundances with concentrations <0.1 ppm to 760 ppm, mostly enriched in V, Cr, Ni, Cu, Zn, Mo, Ba and U. Element ratios of Ni/Co, V/Cr, U/Th and V/(V+Ni) plus U were used to identify redox conditions. The shale-normalized rare earth element (REE) patterns are characterized by the flat-shale type with instable Ce anomalies and very weekly positive Eu anomalies. Positive Ceanom values are significant with values varying between –0.064 and 0.029 in Biluo Co, which may be interpreted as release of REE and input of riverine terrestrial matter with rich Ce (resulting in pH change) during the anoxic conditions. In the middle parts of Amdo 114 station, distinct negative Ceanom values are observed (?0.238 to ?0.111) and associated surface water warming were interpreted as being related to a major sea level rise. In contrast, the formation of the black shales in the lower and upper part of the studied succession took place during a cooler (Ceanom values >–0.10), lower surface water productivity, and lower sea-level stage. Thus, we emphasize the role of different factors that control the formation of local and regional black shales. The most important factors are sea-level fluctuations and increasing productivity. 相似文献
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西沙北部海域海洋环境噪声频谱特性 总被引:2,自引:1,他引:1
Ambient noise is very important in the prediction system of a sonar performance, because it determines the detection ranges always in a passive sonar and usually in an active sonar. In the uncertainty issue for the so-nar performance, it is necessary to know this factor's statistical characteristics that are only obtained by data processing from the underwater ambient noise measurements. Broad-band ambient noise signals from 16 hydrophones were amplified and recorded for 2 min every 1 h. The results show that the ambient noise is essentially depth independent. The cross correlation of the ambient noise levels (1, 6 and 12 h average) with a wind speed is presented. It was found that the correlation is excellent on the upper frequency band and the noise levels correlate better with high wind speed than with low wind speed. 相似文献
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<正>2013年,在中国气象局党组和省委省政府的坚强领导下,全省气象部门广大干部职工齐心协力、奋发进取,出色地完成了各项工作任务。黑龙江省气象局被中国气象局评为优秀达标单位,并进入全国前6名;继2012年以来再次获得中国气象局工作创新奖1项;公众气象服务满意度名列全国第二名(91.5分),连续五年位居全国前3名;获得省部级以上奖励32项。 相似文献
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Over the past nine years, the US Coast Guard has incorporated the prevention through people (PTP) philosophy as a “human factors” approach to learn how maritime operations can be regulated safer and be more efficient by evaluating training, management policies, operational procedures, and establishing partnerships with the maritime industry. One of the key elements of applying a PTP approach is identifying and incorporating lessons learned from major marine casualties and pollution incidents. Since 1997, the US Coast Guard National Strike Force has responded to three major oil spills involving foreign freight vessels grounding, which included the removal of highly viscous oil using various lightering equipment and systems. An informal workgroup consisting of the US Coast Guard, US Navy Supervisor of Salvage (NAVSUPSALV), and various representatives from oil pollution clean-up companies met at the following facilities: the Chevron Asphalt Facility in Edmonds, WA (September 1999), the Oil and Hazardous Materials Simulated Environmental Test Tank (OHMSETT) testing facility in Leonardo, New Jersey (November 1999 and March 2000), the Alaska Clean Seas (ACS) warehouse annex in Prudhoe Bay, AK (October 2000), and Cenac Towing Company facility in Houma, LA (May 2002). The group shared ideas and techniques, and tested different pumps and hose lengths with viscous oil. It was during the early tests that the first quantitative results showed just how efficient lubricated transport of heavy oil product could be, and broadened the knowledge of such methods to the entire industry. Although this technology had existed for many years in the oil production and handling industry, its use had never been investigated in a laboratory setting with regard to salvage response lightering systems. 相似文献