Experimental study of the dependence of embryonic development of Trachurus trachurus eggs on temperature     

Cunha  M. Emilia; Vendrell  Catarina; Goncalves  Patricia 《ICES Journal of Marine Science》2008,65(1):17-24

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Advances in understanding of the mechanism for generation of earthquake thermal precursors detected by satellites     

Arun K. Saraf  Vineeta Rawat  Swapnamita Choudhury  Sudipta Dasgupta  Josodhir Das 《International Journal of Applied Earth Observation and Geoinformation》2009

Stresses building up during an earthquake preparation phase also manifest themselves in the form of a so called increased land surface temperature (LST) leading to a thermal precursor prior to the earthquake event. This phenomenon has now been validated by our observations of short-term thermal anomalies detected by infrared satellite sensors for several recent past earthquakes around the world. The rise in infrared radiance temperature was seen to vary between 5 and 12 °C for different earthquakes. We discuss in this paper different explanations for the generation of such anomalies that have been offered. Emission of gases due to the opening and closure of micropores upon induced stresses and also the participation of ground water have been propounded as a possible cause for generation of thermal anomalies. Seismo-ionosphere coupling, by which gases like radon move to the earth–atmosphere interface and cause air ionization thus bringing about a change in air temperature, relative humidity, etc., has been put forth by some workers. A mechanism of low frequency electromagnetic emission was tested and experimented by scientists with rock masses in stressed conditions as those that exist at tectonic locations. The workers proposed the positive hole pair theory, which received support from several scientific groups. Positive holes (sites of electron deficiency) are activated in stressed rocks from pre-existing yet dormant positive hole pairs (PHPs) and their recombination at rock–air interface leads to a LST rise. A combination of remote sensing detection of rock mechanics behavior with a perception of chemistry and geophysics has been applied to propose the remote sensing rock mechanics theory. Remote sensing detections of such anomalies confirm so far proposed lab theories for such a hotly debated field as earthquake precursor study by providing unbiased observations with consistency in time and space distribution.  相似文献   

SOHM型氢钟在国家授时中心的运行情况分析     

刘春侠  王正明 《时间频率学报》2006,29(2):142-150

上海天文台研制的型号为SOHM-3和SOHM-4的3台氢原子钟在中国科学院国家授时中心(NTSC)已经运行了一年多时间。收集了每个氢原子钟与NTSC主钟的时间比对数据。数据的分析结果给出了这几台氢钟在不同采样间隔上的频率稳定度,也显示出1台氢钟明显的相位跳变,讨论了这种相位跳变的原因。比较了这3台氢钟和从美国进口的Symmetricom公司制造的氢钟的频率稳定度的温度变化效应,指出了上海天文台研究制的氢钟存在的主要问题。  相似文献   

A modified land surface temperature split window retrieval algorithm and its applications over China   总被引：1，自引：0，他引：1  

Hu Yang  Zhongdong Yang 《Global and Planetary Change》2006,52(1-4):207

Due to the difficulties in correcting the influences of the atmosphere absorbability and the Earth surface emissivity diversification, the retrieval of LST (land surface temperature) from satellite data is a challenging task. In this paper, a modified Becker's split window LST inversion algorithm is developed for retrieving LST from the NOAA-16/17 AVHRR data. A new set of parameters for Becker's LST algorithm is proposed. The algorithm is developed from a surface brightness temperature dataset generated from the MODTRAN program, which uses a range of surface parameters and atmospheric quantities as inputs. The 10-day composites of the channels 4 and 5 brightness temperature data of NOAA-17 AVHRR (1-km resolution) are used to generate the clear-sky LST. As a validation of the algorithm, the retrieved LST is compared with MODIS LST of same period and area. The two LST products are found to be consistent, with the absolute difference being about 2.5 K for most areas. The NOAA retrieved LST is also compared with in-situ ground surface 0-cm measurements taken from 257 meteorological stations, which cover overall China area for the three periods of satellite observations. The comparison shows that the correlation between the retrieved LST and in-situ measurements is over 0.90 and the RMSE (root mean square error) is about 3.4 K.  相似文献   

ANALYSIS OF MESOSCALE CONVECTIVE SYSTEMS OVER TIBETAN PLATEAU IN SUMMER     

GUO Zhong-yang DAI Xiao-yan WU Jian-ping LIN Hui 《中国地理科学(英文版)》2006,16(2):116-121

1INTRODUCTION In meteorological satellite cloud images, the features of Mesoscale Convective System (MCS) are shown in white bright cloud cluster, cloud band, cloud line, vorti- calcloudsystem,etc. The MCSlife cycle and spatial size usuallyvaryfrom several hours to one day and 100km to approximately 1000km, respectively. In the last two decades, it has been proven that storm and intensive con- vective weather, such as spasmodic thunderstorm and gale, tornado and short macro-precipitati…  相似文献   

Examination of Daytime Length''''s Influence on Phytoplankton Growth in Jiaozhou Bay, China   总被引：4，自引：0，他引：4  

杨东方  高振会  张经  崔文林  石强 《中国海洋湖沼学报》2004,22(1)

1　INTRODUCTIONSystematicstudyisusefulforhumanvisualizationandcomprehensionofanetworkofcomplicatedcompo nentsandprocessesinvolvingfrequentenergyflow ,consideringenergyasthebasisofbothstructureandprocess (Automa ,1 993) .Energylanguageisaconceptfordepictingasysteminwhichallphenomenaareac companiedbyenergytransformation .Thefunctionoftheecosystemovertheworlddependsontheenergyfixationbymarineplantphotosynthesis ,mostofthemarefixedbymicrophytoplanktonnearseasurfaceexposedtosunlight (Niebaken …  相似文献   

EFFECT OF RATION, TEMPERATURE AND BODY WEIGHT ON GROWTH OF BLACK PORGY,SPARUS MACROCEPHALUS (B.)     

李军  徐世宏  徐长安 《中国海洋湖沼学报》1997,(4)

ChntnbutionNo.3127fromtheInstituteofOceanology,ChinereAcademyofSciences.Project39370542supportedbyNSFCandstudyalsosupportedbyNationalKeyLaboratoryintheInstituteofHydrobiology.ChineseAcademyofSciences.lNTRODUCTIONltisknownthatgroWthrateoffishcanvary'inresponsetotemperatureandfoodavailability-andperhapslessobviously,tolight,oxygenandothervariables.ThispropertyofvariablegroWthinfishcanbereferredtoasplasticity(Weatheriey,l990).TheeffeCtSofenvironmenta1thCtorsongroWthcanbepredictalfor…  相似文献   

Water temperature and conductivity variability as indicators of groundwater behaviour in complex aquifer systems in the south‐east of Spain     

L. Molina  A. Vallejos  A. Pulido‐Bosch  F. Snchez‐Martos 《水文研究》2002,16(17):3365-3378

Groundwater temperature and electrical conductivity logs were applied in this study to gain an understanding of the hydrogeological behaviour of a complex system. This system, compartmentalized by a large number of fractures, which may even cause geothermal anomalies, is that of the Campo de Dalías in the south‐east of the Iberian Peninsula. In addition to this complexity one must consider the different levels with aquifer properties and their varying lithologies, which in some cases are in direct contact with the sea. Vertical sections based upon the various logs allow lateral correlation to be made between the anomalies detected, and provide information on the existence of both ascending and descending vertical flows, and the inflow of sea water into the system. Analysis of environmental isotopes (¹⁸O and D) indicate the areas of recharge with the greatest flow velocity. No seasonal variation in the isotopes was observed, which suggests that the residence time of the groundwater in the aquifer is several years. Radiocarbon dating gave estimates of generally long residence times, although in some sectors it is possible to detect the current recharge based on its tritium content, from rainwater infiltration or seawater intrusion. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

Thermal conductivity and well logs: a case study in the Paris basin   总被引：3，自引：0，他引：3  

L. Demongodin  B. Pinoteau  G. Vasseur  R. Gable 《Geophysical Journal International》1991,105(3):675-691

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Optimum temperature for the growth performance of juvenile orange-spotted grouper （Epinephelus coioides H.）     

林祥志  解绶启  苏永全  崔奕波 《中国海洋湖沼学报》2008,26(1):69-75

Effects of water temperature （17, 21, 25, 30 and 35℃） and body size （14.75-281.41 g initial body weight） on food consumption, growth, feed conversion, and dry matter content in orange-spotted grouper fed to satiation were investigated. The combined effect of temperature （T, ℃） and body weight （W, g） on maximum food consumption （Cmax, g/day） was described as： InCmax=-7.411＋0.828 InW＋0.317T4）.004 7T2, and the optimum feeding temperature was 33.9℃. The combined effect of temperature and body weight on growth （G） was described as： lnG=-4.461-0.2081nW＋0.394T-0.006 3T^2. The optimum growth temperature was 31.4℃, whereas overall growth rates were high at 25, 30 and 35 ℃. Feed conversion efficiencies （FCE, %）, increasing first and then decreasing with increasing temperature, averaged from 1.8 to 2.1 in terms of dry weight of food fish. The optimum temperature for FCE tended to be lower than that for growth or feeding. Dry matter content increased with both increasing water temperature （17, 25, 30 and 35℃） and body weight, and the combined effect of temperature and body weight on dry matter content （DM, %） was described as： lnDM =3.232＋0.01 4 lnW-0.004 4T＋0.001 2TInW.  相似文献