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1.
Zusammenfassung Auf Grund von Messungen im Gemünder Maar/Eifel in den Jahren 1959 und 1960 wird der Jahresverlauf der Temperatur in verschiedenen Tiefen und das Verhalten der Sprungschicht diskutiert. Zusammen mit Registrierungen der Globalstrahlung in Köln ergibt sich ein Einblick in den Wärmehaushalt des Sees.
Summary Based on measurements in the Gemünder Maar/Eifel during the years 1959 and 1960, the annual variation of water temperature in different depths and the behaviour of the discontinuity layer (thermocline) are discussed. Taking into consideration records of global radiation in Cologne, and estimation of the thermal economy of the lake is possible.
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2.
本文对1959年7月及1960年11月有关太阳貭子爆发的各种地球物理效应,作了較全面和系統的論述。文中在§2-4分別敘述了这期間地磁場扰动、极盖区电波吸收观測与电离层变动情况、以及太阳耀斑与太阳射电爆发.根据以上情况,作者特別着重在§5中論述宇宙綫强度扰乱分析(包括各国进行研究的基本情况、若干特殊分析方法与結果簡介、关于綜合观测和高空探測),并在§6中提出了今后开展工作的几点初步意見。本文引用了北京台的磁暴与宇宙线强度变化記录,并附有較完全的文献目录。  相似文献   

3.
Monthly mean geopotential data at five tropical stations for the period 1959–1969 have been used to estimate the vertical distribution of tropospheric temperature change associated with the Mt. Agung volcanic eruption in March 1963. The estimate is that tropospheric temperature decreased by up to 1K with the maximum cooling occurring between August 1964 and August 1965, it is complicated by sea surface temperature changes. It is suggested that the change occurs either directly, by absorption of nearinfrared radiation by the stratospheric aerosol leading to less gaseous absorption and less heating in the troposphere, or indirectly by absorption of solar radiation and a concomitant decrease in evaporation and latent heat release in the troposphere.  相似文献   

4.
A 8.9 ha (22 acre) catchment at the Coweeta Hydrologic Laboratory in western North Carolina was cleared of hardwood forest in 1958 and 1959 and seeded to Kentucky 31 fescue grass in 1959 and 1960. Grass production was high in years when fertilizer was applied and water yield was very similar to that expected from the original forest cover. as grass production declined, so water yields rose, with important increases in the magnitude of both low frequency flows and, particularly, in baseflow. in 1967 and 1968, when all vegetation was deadened in the catchment, the discharge levels in all flow frequency classes were higher. Natural revegetation was then allowed and water yields gradually declined towards the expected level, although there remained a tendency for winter flows to remain higher, and for summer flows to be lower than expected. This paper updates the earlier work of Hibbert (1969) and uses flow duration curves to extend his results.  相似文献   

5.
Establishing predevelopment benchmark groundwater conditions is challenging without long-term records to discern impacts of pumping and climate change on aquifer levels. Understanding periodic natural cycles and trends require 100 years or more data which rarely exist. Using limited records, we develop an approach to hindcast multidecadal levels and examine the temporal evolution of climatic and pumping impacts. The methodology includes a wavelet-aided statistical model, constrained by temporal scales of physical processes responsible for groundwater level variation, including rainfall, evapotranspiration and pumping stresses. The model and hindcasts are tested at three sites in Florida using traditional split calibration-verification methods for the period of record and with the documented historical drought and wet years for the period of no-record. The pumping impact is quantified over time and compared with regional groundwater models, revealing that withdrawals are responsible for 30 to 70% of the declines in levels since 1960s. Hindcasting yielding 110 years of monthly levels is used to assess the effect of climate change and pumping on the frequency of critical low levels. At all three sites, the frequencies of critical low levels increase significantly in the 1960 to 2015 period when compared to the 1904 to 1959 period. For example, at site 1, the return period of the critical low level is shortened by 3.9 years due to climate change and 2.2 years due to pumping.  相似文献   

6.
Summary Records of underwater explosions in Iceland in 1959 and 1960, mainly performed for crustal studies, have been investigated with regard to amplitudes. The amplitudes ofP2 in the 1959 explosions and of the first arrivingP waves in the 1960 explosions were found to be proportional to the first power of the charge weight, whereas amplitudes ofP1 andS1 in the 1959 explosions were proportional to the 3/4-power of the charge up to 200 kg, but increased much slower for larger charges. The influence of water depth of shot point on the charge weights, required to obtain a certain amplitude, has been determined and it was found that the logarithm of the charge weight has a linear relation to water depth down to about 8 meters. The amplitudes of first arrivingP waves decrease as the inverse 2.2-power of the distance up to about 30 km. For greater distances an exponential decrease of the form (const./) exp (–) is valid. ForP2 waves with a frequency of 10 cps we found =0.027±0.003 km–1 for a profile across central Iceland and =0.009±0.004 km–1 for a profile in the western part of Iceland.
Zusammenfassung In den Jahren 1959 und 1960 wurden auf Island Unterwasser-Explosionen ausgelöst, deren Hauptziel Untersuchung der Erdkruste waren. Die Aufzeichnungen der Explosionen werden hier in Hinsicht auf die Amplituden der Wellen untersucht. DieP2-Amplituden in den Explosionen von 1959 und die Amplituden der zuerst ankommendenP-Wellen in den Explosionen von 1960 waren proportional der ersten Potenz des Ladungsgewichtes, während diePl-undSl-Amplituden in den Explosionen von 1959 proportional der 3/4-Potenz des Ladungsgewichtes bis 200 kg waren. Für höhere Ladungsgewichte wuchsen die Amplituden langsamer an. Es wurde der Einfluss der Tiefe des Schusspunktes unterhalb des Wasserspiegels auf das für eine gewisse Amplitude benötigte Ladungsgewicht bestimmt. Es ergab sich dabei, dass der Logarithmus des Ladungsgewichtes in einer linearen Beziehung zur Tiefe, bis etwa 8 m, steht. Die Amplituden der zuerst ankommendenP-Wellen sind umgekehrt proportional der 2.2-Potenz der Entfernung, bis etwa 30 km. Für grössere Entfernungen ist die Abnahme der Amplituden exponential und kann durch (Konst./) exp (–) dargestellt werden. FürP2 mit einer Frequenz von 10 cps haben wir =0.027±0.003 km–1 für ein Profil in Zentral-Island und =0.009 ± 0.004 km–1 für ein Profil in West-Island gefunden.
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7.
Understanding low flow variability is critical for assessing water quality and health of riverine ecosystems in a river basin. Low flows are dependent on human water abstraction as well as the climate variability. This paper investigates the changing nature of low flows and their association with large-scale climate variability for different watersheds in the State of Texas, USA. For this purpose, we employed trend, wavelet analysis and linear as well as nonlinear correlations to identify important changes in low flow characteristics for three stream-gauging stations selected from different (i.e. Brazos, Colorado and Trinity) river basins located in Texas for the time period of 1916–1959 and 1960–2003. We also investigated the teleconnections between low flow variables and the large-scale climate indices (NINO 3.4, SOI and PDO) using cross wavelet analysis as well as their linear and non-linear correlation relationship. Our results indicated that the low flow magnitudes have shown considerable different characteristics for selected river basins during two separate time periods (1916–1959 and 1960–2003). Based on cross wavelet analysis, we identified that the low flows in selected stations of Colorado and Trinity River basins are likely to be influenced by all three large-scale climate indices. In addition to that, we identified that low flows are more nonlinearly associated with climate indices. Among the selected River basins, the stronger association between low flows and large scale climate indices are observed for Trinity River basin. The results from this study can help in better understanding of low flow hydrology and their potential relationship with large scale indices.  相似文献   

8.
The concentration of Sr90 in rain in the N. Hemisphere rises to maximum values in sub-tropical latitudes and above 60oN. There is evidence that the relative distribution varies with season. During 1959 the ratio Sr89/Sr90, and and hence the ratio of polar (high latitude) to equatorial Sr90 activity remained substantially independent of latitude.During the same period the ratio Zr95/Cs137 measured in atmospheric debris at 55oN was significantly higher in the troposphere than in the lower stratosphere.The ratio Ce144/Cs137 in tropospheric air samples (55oN) shows that the proportion of polar debris was 50% during 1959 until July when it fell to a lower value that was sustained during 1960. The Cs137 activities due to polar and equatorial explosions may be separated during this period by use of this ratio.The separate observations summarized above provide, in combination a set of conditions that must be satisf ed by any model of the mechanism of storage in the stratosphere and of transfer between stratosphere and troposphere.The paper was published in Nature, Vol. 192, p. 497 (1961).  相似文献   

9.
Summary The lunar semidiurnal variation of ionospheric absorption at Freiburg and of thef 0 F2 at, Genova, Freiburg and Léopoldville has been deduced. The results are compared with those obtained by other Authors. Magnetic dip, rather than geomagnetic latitude, is found to be a parameter controlling the morphology of the lunar semidiurnal variation of theF2 layer. Finally, a graphical representation of the amplitude of lunar semidiurnal variation off 0 F2 as function of the magnetic dip is also given.
Riassunto Viene determinata la variazione lunare semidiurna dell'assorbimento ionosferico per Friburgo e della frequenza critica dello stratoF2 per Genova, Friburgo, Léopoldville. I risultati sono confrontati con quelli ottenuti da altri Autori per varie stazioni situate in diverse parti del globo. In particolare si trova che la inclinazione magnetica, meglio della latitudine geomagnetica, è il parametro che regola la morfologia della variazione lunare inF2. Infine si dà una rappresentazione grafica dell'ampiezza della variazione lunare dellaf 0 F2 come funzione dell'inclinazione magnetica.


This research was supported by a grant from the Committee on Lunar Variation (IAGA). The paper has been presented at the XII-Assembly of the I.G.G.U. in Helsinki (July–August 1960).  相似文献   

10.
Abstract

Trends in rainfall series were investigated at 16 stations in Ghana over the period 1960–2005. Time series were first de-correlated using an effective pre-whitening methodology and then submitted to the resampling-based Mann-Kendall test. Field significances were assessed using the regional average Kendall statistic. Although no significant changes were observed in annual rainfall, the analysis reveals: (a) a reduction in the number of wet season days totalling less than 20 mm of rainfall, between latitudes 6° and 9.5°N; (b) a delay (about 0.5 d year‐1) in the wet season onset at several locations throughout the country; and (c) a lengthening (about 0.1 d year‐1) of rainless periods during the wet season in the south and centre of Ghana. All these changes, which remained insignificant at more than half of the individual stations, were found to be regionally significant at the 95% confidence level. The results highlight the importance of evaluating regional significance when investigating climate trends.

Editor Z.W. Kundzewicz

Citation Lacombe, G., McCartney, M., and Forkuor, G., 2012. Drying climate in Ghana over the period 1960–2005: evidence from the resampling-based Mann-Kendall test at local and regional levels. Hydrological Sciences Journal, 57 (8), 1594–1609.  相似文献   

11.
Heat and mass transfer rates were studied at the Niragongo lava lake during two expeditions directed by H. Tazieff in 1959 and 1972. The results of this study are as follows:Heat is transferred to the surface of the lake by the movement of lava; gas discharge is a result and not the cause of convection. The chemical composition of the gases and magma has changed very little between 1959 and 1972, whereas the mass and energy outputs differ by an order of magnitude. In 1977 a catastrophic explosion seems to have been caused by tectonic factors, stopping the slow convection of magma under the volcano and hence reducing surface manifestations in the form of the lava lake and escaping fumarolic and magmatic gases. The gas discharge was, in tons day−1, 5000 for H2O, 11,000 for CO2, 1000 for SO2 in 1959, and in 1972 7700 for H2O, 180,000 for CO2 and 23,000 for SO2. These values correspond to an energy transfer of 0.9 × 109 W in 1959 and 16 × 109 W in 1972.  相似文献   

12.
Ohne Zusammenfassung Referat, gehalten am Kolloquium der Hydrobiologischen Kommission und der Gletscherkommission der S.N.G. vom 22. Januar 1960.  相似文献   

13.
Ohne Zusammenfassung Referat, gehalten am Kolloquium der Hydrobiologischen Kommission und der Gletscherkommission der S.N.G. vom 22. Januar 1960.  相似文献   

14.
The sediment record, as revealed in sediment cores, can be used to reconstruct the history of contaminant input into estuaries. The basic assumptions are that contaminant inputs equilibrate relatively rapidly with sediment inputs and that the sediment column represents a continuous sequence of sediment and associated contaminant accumulation. With radiochemical chronologies, it is possible to date sediments over a period corresponding to about five half-lives (100 years for 210Pb). In our study we reconstruct the pollution history of the Savannah Estuary, which is a typical estuary in the South Atlantic Bight. A series of cores were taken in the estuary, followed by the analysis of the cores for a variety of organic and inorganic contaminants. Ages were assigned to different depth intervals by the use of two radiotracers, 210Pb and 137Cs. The major pesticides found were an isomer of DDT and dieldrin. The peak in their concentrations (1967) correlated with peak use of these pesticides before their use was banned. Between 1959 and 1962, there was more input of anthropogenic PAHs than before and after this period. The metals which showed significant changes in the cores include mercury, lead and chromium. Chromium reached a maximum during the late 1950s, followed by a decrease in the late 1960s. This chromium peak coincided with the initial operation of a titanium dioxide pigment plant in the Savannah Estuary. An interesting aspect of the study, which has been noted by many pollution history studies, was the decrease in the concentration of anthropogenic chemicals during the past two decades, suggesting that pollution controls have been effective, even while industrial and population growth was taking place.Similar studies have been carried out to reconstruct the historical record of contamination in the Baltic Sea. Concentrations of metals were found to increase after 1880 (industrial revolution in northern Europe). PCBs peaked in concentration in the late 1960s and the early 1970s, while DDT peaked in the 1960s. The Baltic experienced a major input of nutrients (N and P) after 1965 resulting from heavy use of fertilizers in this region.  相似文献   

15.
Summary On November 1960 a special solar activity occured, producing characteristic disturbances in the ionosphere. Athens center followed this activity by vertical sounding and by Riometer recordings. They are evidences for proton events producing deep absorption in the ionosphere and aurora extending till 38° latitude. Some observations concerning July 1961 solar activity are reported. World wide decrease of the maximum electron density reported during the November period was observed also in Athens. Ionospheric disturbances following vertical sounding observations are of «negative» type.  相似文献   

16.
Zusammenfassung Während der grossen Sonnen-Eruption vom 29.3.60 wurde bei Registrierungen der kosmischen Radio-Strahlung zuerst eine Abnahme beobachtet, der hohe Intensität nachfolgte, die mehrere Stunden anhielt. Die Abnahme entspricht der Mögel-Dellinger-Absorption; es ergibt sich, dass der Radio-Strahlungs-Ausbruch viel länger dauerte als der UV- oder Röntgen-Strahlungs-Ausbruch, der den Mögel Dellinger-Effekt verursachte.
Summary Recording cosmic radio noise during the large solar eruption of march 29, 1960 a decrease of intensity has been observed at first which was followed by high intensity lasting several hours. The decrease being due to SID absorption it appears that the noise-burst lasted much longer than the uv- or x-ray eruption causing the SID.
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17.
Zusammenfassung Es wurde versucht, aus V. T. Timofeevs [1960] Arbeit über die Wassermassen des Arktischen Beckens Aufschlüsse über die klimatischen Änderungen im Nordpolarmeer zu gewinnen. Das Ergebnis ist, daß die von der Fram-Drift (1893–1896) bis zur Sedow-Drift (1937–1940) erhöhte Wärme des Atlantischen, Wassers im Nördlichen Eismeer sich im ganzen bis zum Ende des Jahrzehnts 1950–1959 gehalten hat. Der Erwärmung des Atlantischen Wassers (in etwa 200 bis 700 m Tiefe) geht eine leichte Abkühlung und eine beträchtliche Salzanreicherung der kalten deckschicht Arktischen Wassers parallel. Als Ursache dafür wird der vom Atlantischen Wasser ausgehende, verstärkte Salz- und Wärmestrom angesehen, wobei verminderte Eisbildung und demzufolge verminderte Investierung freiwerdender Erstarrungswärme das geringe Kälterwerden des Arktischen Oberwassers erklären könnte.
The situation as to the warming of the Arctic Basin
Summary V. T. Timofeev's [1960] paper on the water masses of the Arctic Basin was used in the attempt to get some information on the climatic changes in the North Polar Sea. The result is that the increased heat of the Atlantic water in the North Polar Sea from the Fram drift (1893–1896) to the Sedow drift (1937–1940) has been maintained, on a whole, until the end of the decade 1950–1959. The warming of the Atlantic water (in depths of about 200 to 700 m) is paralleled by a slight cooling and a considerable increase in the salinity of the cold surface layer of the Arctic water. The stronger convective flow of salt and heat from the Atlantic wate risregarded to be the reason, as the decrease in the formation of ice and the correspondingly smaller amount of the heat of solidification could explain the slight cooling of the Arctic surface water.

Qu'en est-il du réchauffement du bassin arctique?
Résumé En utilisant les travaux de V. T. Timofeev [1960] sur les masses d'eau du bassin arctique, on a essayé de trouver des indications aux changements de climat dans les mers polaires du Nord. Le résultat est que depuis la dérive du «Fram» (1893–1896) jusqu'à la dérive du «Sedow» (1937–1940) un accroissement de la chaleur de l'eau atlantique dans la mer de Glace du Nord a eu lieu et que cette chaleur augmentée s'est maintenu jusqu'à la fin de la décennie 1950–1959. Parallèlement au réchauffement de l'eau atlantique (par environ 200 à 700 m de profondeur), se produisent un léger refroidissement et une augmentation notable de la salinité de la couche superficielle de l'eau arctique. On pense que ceci ert dû aucourant chaud et salé en provenance de l'eau atlantique; il en résulte une diminution de la pénétration de la chaleur libérée par la congélation qui pourrait expliquer le léger refroidissement de l'eau arctique superficielle.


Hierzu Tafel 10 mit Tab. 1–8 und Tafel 11 mit Tab. 9–14  相似文献   

18.
In this study, the regional tree‐ring chronology of Picea crassifolia was used to estimate annual (September to August) streamflow of the Shiyang River for the period from AD 1765 to 2010. The linear regression model was stable and could explain 41.5% of the variance for the calibration period of 1955–2005. According to the streamflow reconstruction, dry periods with below average streamflow occurred in AD 1775–1804, 1814–1823, 1831–1856, 1862–1867, 1877–1885, 1905–1910, 1926–1932, 1948–1951, 1960–1963 and 1989–2002. Periods of relatively wet years are identified for AD 1765–1774, 1805–1813, 1824–1830, 1857–1861, 1868–1876, 1886–1904, 1911–1925, 1933–1947, 1952–1959, 1964–1988 and 2003–2010. Comparisons with the precipitation reconstructions from surrounding areas supplied a high degree of confidence in our reconstruction. Our reconstructed streamflow is significantly correlated with sea surface temperature in the eastern equatorial Pacific Ocean and the North Atlantic Ocean. The Multitaper spectral and correlation analyses also suggested that the reconstructed streamflow variation in the Shiyang River could be associated with large‐scale atmospheric‐oceanic variability, such as El Niño‐Southern Oscillation (ENSO). The linkages among the streamflow reconstruction, NAO and ENSO suggest the connection of regional streamflow variations to the Asian monsoon and westerlies circulations. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

19.
Characteristics of contemporary climate change in the Tibetan Plateau have been investigated based on the observational data of monthly mean air temperature, monthly mean maximum and minimum air temperatures, and precipitation amount at 217 stations in the Plateau and its adjacent areas in 1951–1998, in which the temperature data at Lhasa, Lanzhou, Kunming and Chengdu were extended to a period of 1935–1950. The following conclusions can be drawn. (1) The air temperature in the Tibetan Plateau decreased from the 1950s to the 1960s, afterwards it began warming up to the 1990s. The data at the Lhasa Station beginning from 1935 have indicated that the air temperature at the station was the highest in the 1940s, then it became cooling until the 1960s. After the 1960s, it began warming until the 1990s. However, the air temperature at Lhasa in the 1990s still did not reach as high as in the 1940s. (2) Since the 1960s, there has existed a cooling belt below 3000 m altitude above sea level, which is located in eastern and southeastern Tibetan Plateau, and there has existed a strong warming belt from south to north in 85–95° E. Because there are very nonhomogeneous and positive-negative alternating changes between cooling and warming belts, the air temperature is not linearly increased with increasing height. (3) Since the 1960s, there has existed a precipitation decreasing belt distributed over southwestern to northeastern Plateau as well as over a below 3000 m a.s.l. area in southeastern Plateau. The warming with decreasing precipitation occurs in the central area of the Plateau and the above 3000 m western Plateau; the warming with increasing precipitation occurs in the northern and southern Plateau; and the cooling with decreasing precipitation occurs in the below 3000 m southeastern Plateau.  相似文献   

20.
李华贞  张强  顾西辉  史培军 《湖泊科学》2018,30(4):1138-1151
根据黄河流域1960—2005年5个水文站逐日流量、77个气象站1959—2013年逐日降水数据,结合流域内主要农作物种植面积及大型水库资料,全面探讨气候与农业面积变化及人类活动对黄河流域径流变化的影响.研究表明:黄河流域所有流量分位数总体呈下降趋势,并于1980s中后期到1990s中期发生突变.降水变化是黄河流域径流变化的主要影响因素.在考虑不同流量分位数情况下,农作物种植面积变化对不同分位数径流变化的影响也有差异性.花园口站农作物种植面积变化对径流量量级和可变性均有显著影响;其余4站各项气候变化与农作物种植指标参数较大,虽均未达到10%的显著性水平,但仍会对径流的量级变化产生影响.对唐乃亥站,农作物耕作面积的下降减少了灌溉用水,在0.5流量分位数时有高达60%增加径流量的间接作用.对于头道拐站,农作物耕作面积的增加使得流域总蒸发量增加,灌溉用水增加,在0.3流量分位数时有高达40%减少径流量的间接作用.该研究为气候变化与人类活动影响下黄河流域水资源优化配置提供重要理论依据.  相似文献   

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