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Sample records for 19th solar cycle

  1. Properties of sunspot cycles and hemispheric wings since the 19th century

    NASA Astrophysics Data System (ADS)

    Leussu, Raisa; Usoskin, Ilya G.; Arlt, Rainer; Mursula, Kalevi

    2016-08-01

    Aims: The latitudinal evolution of sunspot emergence over the course of the solar cycle, the so-called butterfly diagram, is a fundamental property of the solar dynamo. Here we present a study of the butterfly diagram of sunspot group occurrence for cycles 7-10 and 11-23 using data from a recently digitized sunspot drawings by Samuel Heinrich Schwabe in 1825-1867, and from RGO/USAF/NOAA(SOON) compilation of sunspot groups in 1874-2015. Methods: We developed a new, robust method of hemispheric wing separation based on an analysis of long gaps in sunspot group occurrence in different latitude bands. The method makes it possible to ascribe each sunspot group to a certain wing (solar cycle and hemisphere), and separate the old and new cycle during their overlap. This allows for an improved study of solar cycles compared to the common way of separating the cycles. Results: We separated each hemispheric wing of the butterfly diagram and analysed them with respect to the number of groups appearing in each wing, their lengths, hemispheric differences, and overlaps. Conclusions: The overlaps of successive wings were found to be systematically longer in the northern hemisphere for cycles 7-10, but in the southern hemisphere for cycles 16-22. The occurrence of sunspot groups depicts a systematic long-term variation between the two hemispheres. During Schwabe time, the hemispheric asymmetry was north-dominated during cycle 9 and south-dominated during cycle 10.

  2. The 19th Project Integration Meeting

    NASA Technical Reports Server (NTRS)

    Mcdonald, R. R.

    1981-01-01

    The Flat-Plate Solar Array Project is described. Project analysis and integration is discussed. Technology research in silicon material, large-area silicon sheet and environmental isolation; cell and module formation; engineering sciences, and module performance and failure analysis. It includes a report on, and copies of visual presentations made at, the 19th Project Integration Meeting held at Pasadena, California, on November 11, 1981.

  3. The significant solar proton events in 20th solar cycle for the period October 1964 to March 1970

    NASA Technical Reports Server (NTRS)

    Atwell, W.

    1972-01-01

    Solar proton data are presented from observations by the Explorer 21, 28, 34 and 41 satellites. The NASA Solar Particle Alert Network (SPAN) solar optical and radio frequency data for the period May 1967 to March 1970 are associated with the proton events observed by the Explorer 34 and 41 satellites; however, missing data are supplemented with data recorded at other international observatories. From a radiation hazard standpoint, NASA is concerned with solar proton events of the order of 10 to the 8th power proton/sq cm. Radiation dose data are presented for some of the large proton events that have occurred thus far in the 20th solar cycle and are compared with some of the large proton events of the 19th solar cycle. Finally, the results of a simple parametric correlation study are presented for both the 19th and 20th solar cycles.

  4. Ground-Level Solar Cosmic Ray Data from Solar Cycle 19

    NASA Technical Reports Server (NTRS)

    Shea, M. A.

    2003-01-01

    The purpose of this grant was to locate, catalog, and assemble, in standard computer format, ground-level solar cosmic ray data acquired by cosmic ray detectors for selected events in the 19th solar cycle. The events for which we initially proposed to obtain these data were for the events of 23 February 1956,4 May 1960, 12 and 15 November 1960 and 18 and 20 July 1961. These were the largest events of the 19th solar cycle. However, a severe (more than 50%) reduction in the requested funding, required the work effort be limited to neutron monitor data for the 23 February 1956 event and the three major events in 1960.

  5. Solar cycle modulation of ENSO variability

    NASA Astrophysics Data System (ADS)

    Kodera, Kunihiko; Thiéblemont, Rémi

    2016-04-01

    Inspired by the work of Labitzke and van Loon on solar/QBO modulation in the stratosphere, Barnett (1989) conducted an investigation on the relationship between the the biannual component of the sea surface temperature (SST) in the equatorial eastern Pacific and the solar activity. He found that the amplitude of biannual component of the SST (BO) is modulated by the 11-year solar cycle: the amplitude of the BO is large during a period of low solar activity, but small during high solar activity. More than 25-years or two solar cycle has passed since his finding, but the relationship still holds. In order to get an insight into the mechanism of the solar modulation of the El Niño Southern Oscillation (ENSO), here we have revisited this problem. Solar cycle modulation of the BO in the tropical SST is discernible since the end of the 19th centuries, but the amplitude modulation is particularly clear after 1960's. The composite analysis of the SST based on the amplitude of the BO during 1958-2012, indicates that the amplitude of BO is larger when the equatorial Pacific temperature anomalies are high in the central Pacific, but low in the eastern Pacific. Central Pacific anomalies extend to the northern hemisphere, while those in the central Pacific spread toward the southern hemisphere. In short, this anomalous SST pattern is similar to the El Niño modoki. In this connection, it should be noted that the solar signal in the tropical SST also exhibits a similar pattern. This suggests that the modulation of the ENSO variability by the solar cycle originates through a modulation of the El Niño Modoki rather than the canonical El Nino.

  6. Solar Cycle Predictions

    NASA Technical Reports Server (NTRS)

    Pesnell, William Dean

    2012-01-01

    Solar cycle predictions are needed to plan long-term space missions; just like weather predictions are needed to plan the launch. Fleets of satellites circle the Earth collecting many types of science data, protecting astronauts, and relaying information. All of these satellites are sensitive at some level to solar cycle effects. Predictions of drag on LEO spacecraft are one of the most important. Launching a satellite with less propellant can mean a higher orbit, but unanticipated solar activity and increased drag can make that a Pyrrhic victory as you consume the reduced propellant load more rapidly. Energetic events at the Sun can produce crippling radiation storms that endanger all assets in space. Solar cycle predictions also anticipate the shortwave emissions that cause degradation of solar panels. Testing solar dynamo theories by quantitative predictions of what will happen in 5-20 years is the next arena for solar cycle predictions. A summary and analysis of 75 predictions of the amplitude of the upcoming Solar Cycle 24 is presented. The current state of solar cycle predictions and some anticipations how those predictions could be made more accurate in the future will be discussed.

  7. An international campaign of the 19th century to determine the solar parallax. The US Naval expedition to the southern hemisphere 1849-1852

    NASA Astrophysics Data System (ADS)

    Schrimpf, Andreas

    2014-04-01

    In 1847 Christian Ludwig Gerling, Marburg (Germany), suggested the solar parallax to be determined by measuring the position of Venus close to its inferior conjunction, especially at the stationary points, from observatories on nearly the same meridian but widely differing in latitude. James M. Gilliss, astronomer at the newly founded U.S. Naval Observatory, enthusiastically adopted this idea and procured a grant for the young astronomical community of the United States for an expedition to Chile. There they were to observe several conjunctions of Venus and oppositions of Mars, while the accompanying measurements were to be taken at the US Naval Observatory in Washington D.C. and the Harvard College Observatory at Cambridge, USA. This expedition was supported by A.V. Humboldt, C.F. Gauß, J.F. Encke, S.C. Walker, A.D. Bache, B. Peirce and others. From 1849 to 1852 not only were astronomical, but also meteorological and magnetic observations and measurements recorded, mainly in Santa Lucia close to Santiago, Chile. By comparing these measurements with those taken simultaneously at other observatories around the world the solar parallax could be calculated, although incomplete data from the corresponding northern observatories threatened the project's success. In retrospect this expedition can be recognized as the foundation of the Chilean astronomy. The first director of the new National Astronomical Observatory of Chile was Dr. C.W. Moesta, a Hessian student of Christian Ludwig Gerling's. The exchange of data between German, American and other astronomers during this expedition was well mediated by J.G. Flügel, consul of the United States of America and representative of the Smithsonian Institution in Europe, who altogether played a major role in nurturing the relationship between the growing scientific community in the U.S. and the well established one in Europe at that time.

  8. Solar activity secular cycles

    NASA Astrophysics Data System (ADS)

    Kramynin, A. P.; Mordvinov, A. V.

    2013-12-01

    Long-term variations in solar activity secular cycles have been studied using a method for the expansion of reconstructed sunspot number series Sn( t) for 11400 years in terms of natural orthogonal functions. It has been established that three expansion components describe more than 98% of all Sn( t) variations. In this case, the contribution of the first expansion component is about 92%. The averaged form of the 88year secular cycle has been determined based on the form of the first expansion coordinate function. The quasi-periodicities modulating the secular cycle have been revealed based on the time function conjugate to the first function. The quasi-periodicities modulating the secular cycle coincide with those observed in the Sn( t) series spectrum. A change in the secular cycle form and the time variations in this form are described by the second and third expansion components, the contributions of which are about 4 and 2%, respectively. The variations in the steepness of the secular cycle branches are more pronounced in the 200-year cycle, and the secular cycle amplitude varies more evidently in the 2300-year cycle.

  9. Astronomical dating in the 19th century

    NASA Astrophysics Data System (ADS)

    Hilgen, Frederik J.

    2010-01-01

    layering in Holocene peat bogs. He specifically linked the exceptionally wet Atlantic period to the prolonged precession minimum at 33,300 yr ago and further related basic stratigraphic alternations to precession induced climate change in general. Such a linkage was also proposed by Grove Karl Gilbert for cyclic alternations in the marine Cretaceous of North America. Extrapolating sedimentation rates, he arrived at an astronomical duration for part of the Cretaceous that was roughly as long as the final estimate of William Thomson for the age of the Earth. Assuming that orbital parameters directly affect sea level, Karl Mayer-Eymar and Blytt correlated the well known succession of Tertiary stages to precession and eccentricity, respectively. Remarkably, Blytt, like Croll before him, used very long-period cycles in eccentricity to establish and validate his tuning. Understandably these studies in the second half of the 19th century were largely deductive in nature and proved partly incorrect later. Nevertheless, this fascinating period marks a crucial phase in the development of the astronomical theory of the ice ages and climate, and in astronomical dating. It preceded the final inductive phase, which started with the recovery of deep-sea cores in 1947 and led to a spectacular revival of the astronomical theory, by a century. The first half of the 20th century can best be regarded as an intermediate phase, despite the significant progress made in both theoretical aspects and tuning.

  10. 19th Annual Residence Hall Construction Report

    ERIC Educational Resources Information Center

    Agron, Joe

    2008-01-01

    The construction of residence hall facilities at colleges and universities continues to be strong, as institutions scramble to meet the housing needs and varied demands of a growing student population. This article presents data collected from 39 new residence hall projects completed in 2007. According to American School & University's 19th annual…

  11. Solar Cycle Variations in the Solar Interior

    NASA Astrophysics Data System (ADS)

    Rhodes, E. J.

    2012-12-01

    This presentation will review the observational evidence for solar cycle-dependent changes in the structure and dynamical motions of the solar interior. It will include the results of studies that have been carried out using the tools of both global and local heiloseismology during Solar Cycles 22, 23, and 24. The presentation will describe results obtained with both ground- and space-based helioseismic programs, and it will also describe the role that these helioseismic studies have played in providing inputs to theoretical studies of the solar dynamo. Among the topics that will be covered are temporal changes in the solar torsional oscillations, the solar meridional circulation, the solar seismic radius, the subsurface vorticity, and the solar p-mode oscillation frequencies and widths. Also covered will be evidence for temporal changes in the solar interior that are related to the emergence of active regions on both the near and far sides of the Sun.

  12. Teratology in Mexico. 19th Century.

    PubMed

    Gorbach, Frida

    2014-01-01

    It was not until the last third of the 19th century, the period in which, according to historiography, the country definitely inserted itself into modernity, that anomalies and monstrosities had a presence in Mexico. Therefore, what I present here are four moments of teratology in Mexico, four dates in which I try to recount how teratology, which still occupied a marginal place within the main themes of national science, not only reached to cover the realm of medical discussions at the time, but also laid the foundations for new disciplines like biology and anthropology.

  13. Three Solar Cycles of Non-Increasing Magnetic Field

    NASA Astrophysics Data System (ADS)

    Hildner, E.; Arge, N.; Pizzo, V. J.; Harvey, J. W.

    2001-05-01

    Since measurements started in the late 19th century, there has been a secular increase (with superposed ripples due to solar cycles) of the aa geomagnetic index. Starting from this observation, Lockwood, Stamper, and Wild (hereafter, LSW) conclude (Nature, 399, 1999; see also Lockwood et al., Astronomy and Geophysics, 40, 1999) that the total source's magnetic flux in the Sun's atmosphere has risen by 41% since 1964\\" and by 130% in the 20th century. However, solar data over nearly three solar cycles - near-daily magnetograms from Mt Wilson, and Wilcox Solar Observatories and newly reanalyzed data from the National Solar Observatory - show no secular trend in overall photospheric flux. More importantly, the magnetic field open to interplanetary space (as calculated from photospheric measurements and assuming potential fields to a height of 2.5 Rsun) fails to show a secular increase over the last three solar cycles. Like LSW, we do not explicitly take account of transient events. Thus, both data and calculations imply that the Sun's average coronal magnetic flux has not increased over the last three solar cycles. Analysis of simulations with the potential field source surface model shows that the interplanetary magnetic flux is not simply related to the overall, photospheric, solar magnetic flux. Both results are in agreement with the findings of Wang, Lean, and Sheeley (GRL, 27, 2000). The topology, not just the strength, of the emergent solar magnetic field is a major determinant of the interplanetary magnetic field experienced at Earth. In principle, secular change in non-potentiality of the coronal field could lead to secular increase in interplanetary magnetic flux, but this seems unlikely.

  14. The phase shift between the hemispheres in the solar activity cycle

    NASA Astrophysics Data System (ADS)

    Shibalova, A. S.; Obridko, V. N.; Sokoloff, D. D.

    2016-10-01

    The shift between the solar activity cycles in the northern and southern hemispheres of the Sun is studied using data on sunspot number and area. The data obtained are compared with archival information on episodes of appreciable solar-cycle asymmetry. The small phase shift between recent activity cycles in the northern and southern solar hemispheres differs considerably from the shift for episodes of appreciable deviations from dipolar symmetry in the sunspot distribution detected with various degrees of confidence in archival astronomical data from the 17th-19th centuries. The current time shift between the hemispheres is insignificant, about 6-7 months. This shift has changed its sign twice in recent solar history; this probably corresponds to more or less periodic variations with a timescale close to the duration of the Gleissberg cycle.

  15. Solar Cycle #24 and the Solar Dynamo

    NASA Technical Reports Server (NTRS)

    Schatten, Kenneth; Pesnell, W. Dean

    2007-01-01

    We focus on two solar aspects related to flight dynamics. These are the solar dynamo and long-term solar activity predictions. The nature of the solar dynamo is central to solar activity predictions, and these predictions are important for orbital planning of satellites in low earth orbit (LEO). The reason is that the solar ultraviolet (UV) and extreme ultraviolet (EUV) spectral irradiances inflate the upper atmospheric layers of the Earth, forming the thermosphere and exosphere through which these satellites orbit. Concerning the dynamo, we discuss some recent novel approaches towards its understanding. For solar predictions we concentrate on a solar precursor method, in which the Sun's polar field plays a major role in forecasting the next cycle s activity based upon the Babcock-Leighton dynamo. With a current low value for the Sun s polar field, this method predicts that solar cycle #24 will be one of the lowest in recent times, with smoothed F10.7 radio flux values peaking near 130 plus or minus 30 (2 sigma), in the 2013 timeframe. One may have to consider solar activity as far back as the early 20th century to find a cycle of comparable magnitude. Concomitant effects of low solar activity upon satellites in LEO will need to be considered, such as enhancements in orbital debris. Support for our prediction of a low solar cycle #24 is borne out by the lack of new cycle sunspots at least through the first half of 2007. Usually at the present epoch in the solar cycle (approx. 7+ years after the last solar maximum), for a normal size following cycle, new cycle sunspots would be seen. The lack of their appearance at this time is only consistent with a low cycle #24. Polar field observations of a weak magnitude are consistent with unusual structures seen in the Sun s corona. Polar coronal holes are the hallmarks of the Sun's open field structures. At present, it appears that the polar coronal holes are relatively weak, and there have been many equatorial coronal holes

  16. Solar Cycle #24 and the Solar Dynamo

    NASA Technical Reports Server (NTRS)

    Pesnell, W. Dean; Schatten, Kenneth

    2007-01-01

    We focus on two solar aspects related to flight dynamics. These are the solar dynamo and long-term solar activity predictions. The nature of the solar dynamo is central to solar activity predictions, and these predictions are important for orbital planning of satellites in low earth orbit (LEO). The reason is that the solar ultraviolet (UV) and extreme ultraviolet (EUV) spectral irradiances inflate the upper atmospheric layers of the Earth, forming the thermosphere and exosphere through which these satellites orbit. Concerning the dynamo, we discuss some recent novel approaches towards its understanding. For solar predictions we concentrate on a solar precursor method, in which the Sun s polar field plays a major role in forecasting the next cycle s activity based upon the Babcock- Leighton dynamo. With a current low value for the Sun s polar field, this method predicts that solar cycle #24 will be one of the lowest in recent times, with smoothed F10.7 radio flux values peaking near 130+ 30 (2 4, in the 2013 timeframe. One may have to consider solar activity as far back as the early 20th century to find a cycle of comparable magnitude. Concomitant effects of low solar activity upon satellites in LEO will need to be considered, such as enhancements in orbital debris. Support for our prediction of a low solar cycle #24 is borne out by the lack of new cycle sunspots at least through the first half of 2007. Usually at the present epoch in the solar cycle (-7+ years after the last solar maximum), for a normal size following cycle, new cycle sunspots would be seen. The lack of their appearance at this time is only consistent with a low cycle #24. Polar field observations of a weak magnitude are consistent with unusual structures seen in the Sun s corona. Polar coronal holes are the hallmarks of the Sun s open field structures. At present, it appears that the polar coronal holes are relatively weak, and there have been many equatorial coronal holes. This appears

  17. Solar Cycle 24 and the Solar Dynamo

    NASA Technical Reports Server (NTRS)

    Pesnell, W. D.; Schatten, K.

    2007-01-01

    We will discuss the polar field precursor method for solar activity prediction, which predicts cycle 24 will be significantly lower than recent activity cycles, and some new ideas rejuvenating Babcock's shallow surface dynamo. The polar field precursor method is based on Babcock and Leighton's dynamo models wherein the polar field at solar minimum plays a major role in generating the next cycle's toroidal field and sunspots. Thus, by examining the polar fields of the Sun near solar minimum, a forecast for the next cycle's activity is obtained. With the current low value for the Sun's polar fields, this method predicts solar cycle 24 will be one of the lowest in recent times, with smoothed F10.7 radio flux values peaking near 135 plus or minus 35 (2 sigma), in the 2012-2013 timeframe (equivalent to smoothed Rz near 80 plus or minus 35 [2 sigma]). One may have to consider solar activity as far back as the early 20th century to find a cycle of comparable magnitude. We discuss unusual behavior in the Sun's polar fields that support this prediction. Normally, the solar precursor method is consistent with the geomagnetic precursor method, wherein geomagnetic variations are thought to be a good measure of the Sun's polar field strength. Because of the unusual polar field, the Earth does not appear to be currently bathed in the Sun's extended polar field (the interplanetary field), hence negating the primal cause behind the geomagnetic precursor technique. We also discuss how percolation may support Babcock's original shallow solar dynamo. In this process ephemeral regions from the solar magnetic carpet, guided by shallow surface fields, may collect to form pores and sunspots.

  18. A Geomagnetic Precursor Technique for Predicting the Solar Activity Cycle

    NASA Astrophysics Data System (ADS)

    Sobel, E. I.; Rabin, D. M.

    2015-12-01

    The Western hemisphere has been recording sunspot numbers since Galileo discovered sunspots in the early 17th century, and the roughly 11-year solar cycle has been recognized since the 19th century. However, predicting the strength of any particular cycle remains a relatively imprecise task. This project's aim was to update and improve a forecasting technique based on geomagnetic precursors of future solar activity The model is a refinement of R. J. Thompson's 1993 paper that relates the number of geomagnetically disturbed days, as defined by the aa and Ap indices, to the sum of the sunspot number in the current and the previous cycle, Rn + Rn-1.[1] The method exploits the fact that two cycles coexist for some period on the Sun near solar minimum and therefore that the number of sunspots and disturbed days during the declining phase of one cycle gives an indication of the following cycle's strength. We wrote and updated IDL software procedures to define disturbed days with varying threshold values and graphed Rn + Rn-1 against them. The aa threshold was derived from the Ap threshold. After comparing the graphs for Ap values from 20 to 50, an Ap threshold of 30 and the corresponding aa threshold of 44 were chosen as yielding the best correlation. Confidence regions were computed to provide a quantitative uncertainty on future predictions. The 80% confidence region gives a range of ±40 in sunspot number. [1] Thompson, R. J. (1993). A technique for predicting the amplitude of the solar cycle. Solar Physics, 148, 2, 383-388.

  19. [Assisted birth in 19th century Bahia].

    PubMed

    Barreto, Maria Renilda Nery

    2008-01-01

    This paper presents the traditions of assisted childbirth in the Brazilian state of Bahia in the 19th Century and develops the hypothesis that two obstetrical traditions coexisted in the capital, Salvador, namely the doctor-midwives--who used technical resources and knowledge acquired from obstetrics as a medical specialty--and the traditional midwives, whose know-how was purely of an empirical-sensorial nature. Despite all efforts employed by the doctors to win over the confidence of Bahian families, the midwives continued to be predominant in the art of 'delivering' children and treating female illnesses. The analysis focuses on the social and professional segments that were active in assisted birth; the role of the Bahian College of Medicine (Faculdade de Medicina da Bahia) in the training and certification of midwives and the use of newspapers as a way to legitimize the doctor-midwives; it also discusses the scant coverage of the midwives in these media.

  20. Solar Cycle 25: Another Moderate Cycle?

    NASA Astrophysics Data System (ADS)

    Cameron, R. H.; Jiang, J.; Schüssler, M.

    2016-06-01

    Surface flux transport simulations for the descending phase of Cycle 24 using random sources (emerging bipolar magnetic regions) with empirically determined scatter of their properties provide a prediction of the axial dipole moment during the upcoming activity minimum together with a realistic uncertainty range. The expectation value for the dipole moment around 2020 (2.5 ± 1.1 G) is comparable to that observed at the end of Cycle 23 (about 2 G). The empirical correlation between the dipole moment during solar minimum and the strength of the subsequent cycle thus suggests that Cycle 25 will be of moderate amplitude, not much higher than that of the current cycle. However, the intrinsic uncertainty of such predictions resulting from the random scatter of the source properties is considerable and fundamentally limits the reliability with which such predictions can be made before activity minimum is reached.

  1. Women in 19th Century Irish immigration.

    PubMed

    Jackson, P

    1984-01-01

    By the 1950s--100 years after the great famine of 1845-49-- 57% of emigrants from the 26 countries of Ireland were women. In the latter 1/2 of the 19th Century, increasing proportions of women emigrated, until they outnumbered men. For women it was more than a flight from poverty. It was also an escape from an increasingly patriarchal society, whose asymetrical development as a colony curtailed women's social space, even in their traditional role as wife and mother. The famine, which is the single greatest influence forcing emigration, undermined the social fabric of an agrarian society, hastening the process of agricultural transformation. The growth of a new class of Irish a British grazier landlords resulted in a situation of acute land scarcity, encouraging tendencies to cling to one's land holding without dividing it. This, combined with new inheritance practices, gave rise to widespread arranged marriages as a means of land consolidation, and the dowry system. The spontaneous marriage practices of famine days also were replaced by a postponement of marriage. These trends severely reduced the choices exerted by women. The absence of big industrialized cities, which might have absorbed displaced rural populations, removed available options, particularly for women. The system of land monopoly and inheritance revolving around male heads of households reinforced partriarchal relations, within a framework of rigid sexual norms, whose enforcement was easy because the church, which played an important role in the emergence of these values, was a major landowner in itself. The subordinated, invisible status of women in post-famine Ireland, and growing barriers to easy access to marriage partners, to waged employment and self-expression, all helped ensure the higher and higher emigration rates of women. The economic transformation of Irish agriculture accelerated the establishment of oppressive values and helped depreciate the position of women to a very low level. The

  2. Women in 19th Century Irish immigration.

    PubMed

    Jackson, P

    1984-01-01

    By the 1950s--100 years after the great famine of 1845-49-- 57% of emigrants from the 26 countries of Ireland were women. In the latter 1/2 of the 19th Century, increasing proportions of women emigrated, until they outnumbered men. For women it was more than a flight from poverty. It was also an escape from an increasingly patriarchal society, whose asymetrical development as a colony curtailed women's social space, even in their traditional role as wife and mother. The famine, which is the single greatest influence forcing emigration, undermined the social fabric of an agrarian society, hastening the process of agricultural transformation. The growth of a new class of Irish a British grazier landlords resulted in a situation of acute land scarcity, encouraging tendencies to cling to one's land holding without dividing it. This, combined with new inheritance practices, gave rise to widespread arranged marriages as a means of land consolidation, and the dowry system. The spontaneous marriage practices of famine days also were replaced by a postponement of marriage. These trends severely reduced the choices exerted by women. The absence of big industrialized cities, which might have absorbed displaced rural populations, removed available options, particularly for women. The system of land monopoly and inheritance revolving around male heads of households reinforced partriarchal relations, within a framework of rigid sexual norms, whose enforcement was easy because the church, which played an important role in the emergence of these values, was a major landowner in itself. The subordinated, invisible status of women in post-famine Ireland, and growing barriers to easy access to marriage partners, to waged employment and self-expression, all helped ensure the higher and higher emigration rates of women. The economic transformation of Irish agriculture accelerated the establishment of oppressive values and helped depreciate the position of women to a very low level. The

  3. Prediction of Solar Cycle Maximum Using Solar Cycle Lengths

    NASA Astrophysics Data System (ADS)

    Kane, R. P.

    2008-03-01

    If the rise time RT, fall time FT, and total time TT ( i.e., RT+FT) of a solar cycle are compared against the maximum amplitude Rz(max ) for the following cycle, then only the association between TT and Rz(max ) is inferred to be well anticorrelated, inferring that the larger (smaller) the value of Rz(max ) for the following cycle, the shorter (longer) the TT of the preceding cycle. Although the inferred correlation (-0.68) is statistically significant, the inferred standard error of estimate is quite large, so predictions using the inferred correlation are not very precise. Removal of cycle pairs 15/16, 19/20, and 20/21 (statistical outliers) yields a regression that is highly statistically significant (-0.85) and reduces the standard error of estimate by 18%. On the basis of the adjusted regression and presuming TT=140 months for cycle 23, the present ongoing cycle, cycle 24’s 90% prediction interval for Rz(max ) is estimated to be about 94±44, inferring only a 5% probability that its Rz(max ) will be larger than about 140, unless of course cycle pair 23/24 is a statistical outlier.

  4. A SOLAR CYCLE LOST IN 1793-1800: EARLY SUNSPOT OBSERVATIONS RESOLVE THE OLD MYSTERY

    SciTech Connect

    Usoskin, Ilya G.; Mursula, Kalevi; Arlt, Rainer; Kovaltsov, Gennady A.

    2009-08-01

    Because of the lack of reliable sunspot observations, the quality of the sunspot number series is poor in the late 18th century, leading to the abnormally long solar cycle (1784-1799) before the Dalton minimum. Using the newly recovered solar drawings by the 18-19th century observers Staudacher and Hamilton, we construct the solar butterfly diagram, i.e., the latitudinal distribution of sunspots in the 1790s. The sudden, systematic occurrence of sunspots at high solar latitudes in 1793-1796 unambiguously shows that a new cycle started in 1793, which was lost in the traditional Wolf sunspot series. This finally confirms the existence of the lost cycle that has been proposed earlier, thus resolving an old mystery. This Letter brings the attention of the scientific community to the need of revising the sunspot series in the 18th century. The presence of a new short, asymmetric cycle implies changes and constraints to sunspot cycle statistics, solar activity predictions, and solar dynamo theories, as well as for solar-terrestrial relations.

  5. A Solar Cycle Lost in 1793-1800: Early Sunspot Observations Resolve the Old Mystery

    NASA Astrophysics Data System (ADS)

    Usoskin, Ilya G.; Mursula, Kalevi; Arlt, Rainer; Kovaltsov, Gennady A.

    2009-08-01

    Because of the lack of reliable sunspot observations, the quality of the sunspot number series is poor in the late 18th century, leading to the abnormally long solar cycle (1784-1799) before the Dalton minimum. Using the newly recovered solar drawings by the 18-19th century observers Staudacher and Hamilton, we construct the solar butterfly diagram, i.e., the latitudinal distribution of sunspots in the 1790s. The sudden, systematic occurrence of sunspots at high solar latitudes in 1793-1796 unambiguously shows that a new cycle started in 1793, which was lost in the traditional Wolf sunspot series. This finally confirms the existence of the lost cycle that has been proposed earlier, thus resolving an old mystery. This Letter brings the attention of the scientific community to the need of revising the sunspot series in the 18th century. The presence of a new short, asymmetric cycle implies changes and constraints to sunspot cycle statistics, solar activity predictions, and solar dynamo theories, as well as for solar-terrestrial relations.

  6. Superactive regions in solar cycle 24

    NASA Astrophysics Data System (ADS)

    Wang, Jingxiu; Chen, Anqin

    2015-08-01

    Solar super active regions (SARs) are characterized by huge sunspot area, strong thermal and non-thermal radiation, severe activity events and obvious decrease of total solar irradiance during their central meridian passage (Chen et al. 2011). They are more close to the star spots observed in integrated stellar radiation. In last 5 solar cycles, the SARs occupied less than 5% of total solar active regions, but hosted more than 40% of X class X-ray flares (or equivalently, major solar flares). With available vector-magnetograph observations, we quantitatively described the SARs in solar cycles 22-23 with four parameters, which were deduced from vector magnetic fields, and suggested a composite vector field Index Icom (Chen and Wang 2012). The SARs with very strong flare activity all have Icom > 1. Comparing with solar cycles 21-23, the level of solar activity in current solar cycle is very low. So far, there are only 5 SARs and 44 X class flares. The monthly smoothed TSI decreased sharply by 0.09% from the maximum of solar cycle 23 to the minima between solar cycle 23 and 24. In this contribution, we present new studies on SARs in solar cycle 24. The SARs in solar cycle 24 have relatively small flare index and relatively small vector field index Icom comparing with the SARs in solar cycles 22 and 23. There is a clearly linear relationship between the flare index and the composite vector field index (Chen and Wang 2015). The emphasis of this contribution is put on the similarity and different behaviors of vector magnetic fields of the SARs in the current solar cycle and the previous ones. We try to get a satisfactory account for the general characteristics and relatively low level of solar flare activity in cycle 24.

  7. A Synthesis of Solar Cycle Prediction Techniques

    NASA Technical Reports Server (NTRS)

    Hathaway, David H.; Wilson, Robert M.; Reichmann, Edwin J.

    1999-01-01

    A number of techniques currently in use for predicting solar activity on a solar cycle timescale are tested with historical data. Some techniques, e.g., regression and curve fitting, work well as solar activity approaches maximum and provide a month-by-month description of future activity, while others, e.g., geomagnetic precursors, work well near solar minimum but only provide an estimate of the amplitude of the cycle. A synthesis of different techniques is shown to provide a more accurate and useful forecast of solar cycle activity levels. A combination of two uncorrelated geomagnetic precursor techniques provides a more accurate prediction for the amplitude of a solar activity cycle at a time well before activity minimum. This combined precursor method gives a smoothed sunspot number maximum of 154 plus or minus 21 at the 95% level of confidence for the next cycle maximum. A mathematical function dependent on the time of cycle initiation and the cycle amplitude is used to describe the level of solar activity month by month for the next cycle. As the time of cycle maximum approaches a better estimate of the cycle activity is obtained by including the fit between previous activity levels and this function. This Combined Solar Cycle Activity Forecast gives, as of January 1999, a smoothed sunspot maximum of 146 plus or minus 20 at the 95% level of confidence for the next cycle maximum.

  8. [Earth magnetism research in the 19th century].

    PubMed

    Schröder, W; Wiederkehr, K H

    2000-01-01

    Even before the discovery of the electromagnetism by Oersted, and before Ampère, who attributed all magnetism to the flux of electrical currents, A. v. Humboldt and Hansteen had turned to geomagnetism. With the help of the "Göttinger Magnetische Verein", a worldwide cooperation under the leadership of Gauss game into existence. Even today, Gauss' theory of the geomagnetism is one of the pillars for geomagnetical research work. Thereafter, J. v. Lamont, Prof. in Munich, took over the leadership in Germany. In England, the Magnetic Crusade was started by the initiative of John Herschel and E. Sabine. At the beginning of the forties, James Clarke Ross advanced to the Antarctic Continent, which was then quite unknown. Ten years later, Sabine was able to gather solar-terrestrial relations from the data of the colonical observatories. In the eighties, Arthur Schuster, following Balfour Stewart's ideas, succeeded in interpreting the daily variations of the electrical process in the high atmosphere. The geomagnetic research work in Germany was given a fresh impetus by the First Polar Year 1882-1883. Georg Neumayer, director of the "Deutsche Seewarte" in Hamburg, had been one of the initiators of the Polar Year. He had a close cooperation with the newly founded "Kaiserliches Marineobservatorium" in Wilhelmshaven, and he also managed to gain the collaboration of the "Gauss-Observatorium für Erdmagnetismus" in Göttingen under E. Schering. In the Polar Year, the first automatic recording magnetometers (Kew-Model) were used in a German observatory in Wilhelmshaven. Here M. Eschenhagen, who later became director of the geomagnetic section in the new Meterological-Magnetic Observatory in Potsdam, gained special merit. The treatise considers preceding hypotheses of geomagnetism as well as the palaeomagnetic studies. The essential seismological investigations at the turn of the 19th to the 20th century are briefly treated. They represent one of the keystones for the modern

  9. Anomalously extended minima of solar cycle~23

    NASA Astrophysics Data System (ADS)

    Singh, Ambika; Tiwari, Anil Kumar; Agrawal, S. P.

    The new millennium extended solar minimum of solar cycle 23 (2007-2009) contains some distinct surprises and is anomalous in comparison to the past few solar cycles. In general, the level of solar activity goes through the cyclic changes lasting roughly 11 years. The last solar cycle 23 started in the year 1996 and was expected to last until 2006. Nevertheless, the solar activity minima continued beyond the year 2006 and lasted till 2009. In fact, anomalously, during the years 2007-09, a deep sunspot minima was observed at the end of the last solar cycle 23. It is observed that the sun had no sunspots continuously for over 50 days in July-August, 2009. More so, it is found that the solar cycle 23 has the longest quiet period as compared to the last many previous solar cycles. Anomalously low values of the geomagnetic disturbance Ap is observed during the whole quiet period (2007-09) of the sun, particularly in the month of January-September 2009, during which the high speed solar wind streams are also not observed. As such, the past solar cycle 23 seems to have the very long period of about 14 years, which is anomalously distinct from previous four solar cycles, besides the obvious Ap correlation of very low activity. The low values of the sunspot numbers in years 2007-2009 also have a very distinct effect in producing lowest modulation in cosmic ray intensity, with highest values of neutron monitor counts observed in the year 2009, as compared to that observed so far in previous solar cycles. These results are discussed in the light of many associated solar-terrestrial phenomena.

  10. Puerperal insanity in the 19th and 20th centuries.

    PubMed

    Rehman, A U; St Clair, D; Platz, C

    1990-06-01

    All patients with puerperal psychosis admitted to the Royal Edinburgh Hospital within 90 days of childbirth during the periods 1880-90 and 1971-80 were compared. The majority of cases in both groups had an affective illness with an acute presentation and a fixed interval of onset. The 19th-century cases had a more florid presentation and a greater length of admission (mean, 151 days) to the hospital than the 20th-century ones (mean, 39 days). The incidence of the disorder rose from 0.34 per 1000 childbirths per year in the 19th-century group to 1.04 in the 20th-century one, but this could be explained by nosocomial factors. Most 19th-century cases occurred in multigravid women, which questions the association of puerperal psychosis with primiparae.

  11. Proceedings of the 19th Space Photovoltaic Research and Technology Conference

    NASA Technical Reports Server (NTRS)

    Castro, Stephanie (Compiler); Morton, Thomas (Compiler)

    2007-01-01

    The 19th Space Photovoltaic Research and Technology Conference (SPRAT XIX) was held September 20 to 22, 2005, at the Ohio Aerospace Institute (OAI) in Brook Park, Ohio. The SPRAT Conference, hosted by the Photovoltaic and Space Environments Branch of the NASA Glenn Research Center, brought together representatives of the space photovoltaic community from around the world to share the latest advances in space solar cell technology. This year's conference continued to build on many of the trends shown in SPRAT XVIII-the continued advances of thin-film and multijunction solar cell technologies and the new issues required to qualify those types of cells for space applications.

  12. Art and Education for Women in 19th Century Boston.

    ERIC Educational Resources Information Center

    Efland, Arthur D.

    1985-01-01

    Art was introduced into women's education in 19th century Boston as a kind of finishing school treatment to equip them for marriage and later for careers as school teachers. Common school art emphasized practical application. Feminine art education, by contrast, promoted the teaching of art as high culture. (Author/RM)

  13. Technical improvements in 19th century Belgian window glass production

    NASA Astrophysics Data System (ADS)

    Lauriks, Leen; Collette, Quentin; Wouters, Ine; Belis, Jan

    Glass was used since the Roman age in the building envelope, but it became widely applied together with iron since the 19th century. Belgium was a major producer of window glass during the nineteenth century and the majority of the produced window glass was exported all over the world. Investigating the literature on the development of 19th century Belgian window glass production is therefore internationally relevant. In the 17th century, wood was replaced as a fuel by coal. In the 19th century, the regenerative tank furnace applied gas as a fuel in a continuous glass production process. The advantages were a clean production, a more constant and higher temperature in the furnace and a fuel saving. The French chemist Nicolas Leblanc (1787-1793) and later the Belgian chemist Ernest Solvay (1863) invented processes to produce alkali out of common salt. The artificial soda ash improved the quality and aesthetics of the glass plates. During the 19th century, the glass production was industrialized, influencing the operation of furnaces, the improvement of raw materials as well as the applied energy sources. Although the production process was industrialized, glassblowing was still the work of an individual. By improving his work tools, he was able to create larger glass plates. The developments in the annealing process followed this evolution. The industry had to wait until the invention of the drawn glass in the beginning of the 20th century to fully industrialise the window glass manufacture process.

  14. Vocational Education in the 19th Century American Academy.

    ERIC Educational Resources Information Center

    Law, Gordon F.

    The phrase "all things useful and all things ornamental," coined by Benjamin Franklin, describes the stated mission of most of the approximately 6,000 educational academies flourishing in America in the mid-19th century. Built upon the roots of Latin grammar schools, the academies evolved to include courses in many areas, from classical studies to…

  15. Woman Suffrage and the 19th Amendment. Teaching with Documents.

    ERIC Educational Resources Information Center

    National Archives and Records Administration, Washington, DC.

    Beginning in the mid-19th century, several generations of woman suffrage supporters lectured, wrote, marched, lobbied, and practiced civil disobedience to achieve what many people considered a radical change in the U.S. Constitution. Militant suffragists used tactics such as parades, silent vigils, and hunger strikes. In 1870 the 15th amendment to…

  16. Forecasting the solar activity cycle: new insights

    NASA Astrophysics Data System (ADS)

    Nandy, Dibyendu; Karak, Bidya Binay

    2013-07-01

    Having advance knowledge of solar activity is important because the Sun's magnetic output governs space weather and impacts technologies reliant on space. However, the irregular nature of the solar cycle makes solar activity predictions a challenging task. This is best achieved through appropriately constrained solar dynamo simulations and as such the first step towards predictions is to understand the underlying physics of the solar dynamo mechanism. In Babcock-Leighton type dynamo models, the poloidal field is generated near the solar surface whereas the toroidal field is generated in the solar interior. Therefore a finite time is necessary for the coupling of the spatially segregated source layers of the dynamo. This time delay introduces a memory in the dynamo mechanism which allows forecasting of future solar activity. Here we discuss how this forecasting ability of the solar cycle is affected by downward turbulent pumping of magnetic flux. With significant turbulent pumping the memory of the dynamo is severely degraded and thus long term prediction of the solar cycle is not possible; only a short term prediction of the next cycle peak may be possible based on observational data assimilation at the previous cycle minimum.

  17. Correlations of solar cycle 22 UV irradiance

    NASA Technical Reports Server (NTRS)

    Floyd, L.; Brueckner, G.; Crane, P.; Prinz, D.; Herring, L.

    1997-01-01

    The solar ultraviolet spectral irradiance monitor (SUSIM) onboard the upper atmosphere research satellite (UARS) is an absolutely calibrated UV spectrometer which has measured the solar spectral irradiance over the wavelengths 115 nm to 410 nm since October 1991. This data set now extends for about six years from near the peak of solar cycle 22, through its minimum, to the initial rise associated with solar cycle 23. Generally, the time series of UV spectral irradiances obtained shows behavior similar to that of other solar activity indices. The conditions on the sun, which can in result in dominant 13.5-day periodicity, are analyzed and illustrated. It is found that any combination of presence or absence of dominant 13.5-day in UV irradiance and solar wind velocity is possible depending entirely on the particular surface distribution and orientation of solar active regions.

  18. [Popular knowledge about medicaments in 19th century periodicals].

    PubMed

    Arabas, Iwona

    2004-01-01

    Polish periodicals published since the beginning of 19th century contained household knowledge which was of great importance to peasants. In the second half of 19th century the number of articles related to prevention, treatment as well as life hygiene (including nutrition guidance) enlarged significantly. The term "household medicine box# was very often used in periodicals as titles of both: sections dedicated to hygiene or medicine as well as for articles describing medicaments intended to be kept in the boxes. Articles referenced law regulations stated in "law for pharmacists and pharmacies# from 1844. The availability of medical handbooks widened with the end of the century and this fact may have caused the changes in profiles of numerous medical sections in popular periodicals. However the changes did not affect publications related to contents of medical boxes.

  19. Disputed discovery: vivisection and experiment in the 19th century.

    PubMed

    Berkowitz, Carin

    2006-09-01

    In the early 19th century, physiologists Sir Charles Bell and François Magendie both claimed to have been the first to identify separate motor and sensory nerve roots, a discovery acknowledged by their contemporaries as one of the most important of the age. This priority dispute came to embody distinct visions of physiology, and of the role of experimentation and vivisection within that discipline. The dispute remained unresolved, in part, because of competing definitions of what was being discovered.

  20. Solar cycle 24 from the standpoint of solar paleoastrophysics

    NASA Astrophysics Data System (ADS)

    Ogurtsov, M. G.

    2016-03-01

    The predictions of the maximum yearly mean sunspot number in the current cycle 24 made by means of the astrophysical approach (by analyzing the instrumental data on solar activity and using various dynamo models) and the paleoastrophysical approach (by analyzing the paleoreconstructions of solar activity spanning the interval from 8555 BC to 1605 AD) are compared. The paleoastrophysical predictions are shown to be considerably more accurate. The amplitude of the next cycle 25 is predicted. It is shown that from the standpoint of solar paleoastrophysics, cycle 25 will most likely be of medium power, R max(25) = 85.0 ± 30.5.

  1. Rankine-cycle solar-cooling systems

    NASA Technical Reports Server (NTRS)

    Weathers, H. M.

    1979-01-01

    Report reviews progress made by three contractors to Marshall Space Flight Center and Department of Energy in developing Rankine-cycle machines for solar cooling and testing of commercially available equipment involved.

  2. On Solar Flares and Cycle 23

    NASA Astrophysics Data System (ADS)

    Kossobokov, V. G.; Le Mouel, J.; Courtillot, V.

    2011-12-01

    The anomalous character of solar cycle 23 has been pointed out. It is proposed that the solar dynamo is undergoing a transition from a state of "grand maximum" to one of "regular oscillations". In this study, we analyze the time distribution of the number and energy of solar flares, and the duration of intervals between them, from cycle 21 to 23. We consider 32355 flares of class C2 and larger (C2+) from the GOES catalogue. Daily values of X-ray flux (wavelengths 1-8Å) have been computed by summing the energy proxies of the events. The series of daily numbers of C2+ solar flares are strongly correlated to their daily energy flux. The long duration of cycle 23 (~13 years), the long interval with no C2+ flare between the end of cycle 23 and the start of cycle 24 (466 days) are remarkable compared to the two earlier cycles. Amplitudes of extreme flares increase when mean flux decreases. We have calculated running averages of energy flux over intervals going from 7 to 365 days: the singular shape of cycle 23 is increasingly striking with increasing interval: the first ~70% of the cycle display (in logarithmic scale) linearly rising maxima, whereas minima are aligned along a descending slope for the latter part of the cycle. Energy flux oscillates between these and takes the shape of a bifurcation, starting near 2002. Durations of inter-event intervals between successive C2+ flares undergo quasi-periodic (~11yr) oscillations between two distinct states, which we call "active" and "quiet", with sharp onset and termination. The ratio of time spent in the active vs quiet states ranges from 1.8 to 1.4 for cycles 21 to 23, cycle 23 having the longest quiet period. It has been proposed that anomalous cycle 23 resembles cycle 4, which was followed by reduced cycles 5 and 6 at the time of the Dalton-minimum in solar activity, often associated with a cooler global climate. It will be interesting to monitor the evolution of solar flares in cycle 24, in order to further our

  3. On Solar Flares and Cycle 23

    NASA Astrophysics Data System (ADS)

    Kossobokov, Vladimir; Le Mouël, Jean-Louis; Courtillot, Vincent

    2012-02-01

    The anomalous character of Solar Cycle 23, which ended in the Summer of 2009, has been pointed out by many authors. It has even been proposed that the solar dynamo is undergoing a transition from a state of “grand maximum” to one of “regular oscillations”. We analyze the temporal distribution of the number and energy of solar flares, and the duration of intervals between them, over Cycles 21 to 23. We consider 32 355 flares of class C2 and larger (C2+) from the GOES catalogue. Daily values of X-ray flux (wavelengths 1 to 8 Å) have been computed by summing the energy proxies of the events. The series of daily numbers of C2+ solar flares are strongly correlated with their daily energy flux. The long duration of Cycle 23 (12.8 years based on sunspots, 13.2 years based on flares) and the long interval with no C2+ flare between the end of Cycle 23, and the start of Cycle 24 (466 days) are remarkable compared to the two earlier cycles. The amplitudes of extreme flares increase when the mean flux decreases. We have calculated running averages of energy flux over intervals going from 7 to 365 days. The singular shape of Cycle 23 is increasingly striking with increasing interval: in the first ≈ 70% of the cycle (displayed on a logarithmic scale) we see linearly rising maxima, whereas minima are aligned along a descending slope for the latter part of the cycle. The energy flux oscillates between these and takes the shape of a bifurcation, starting near 2002 (a time when it is suggested that photospheric fields were abruptly reduced). Inter-event intervals between successive C2+ flares undergo quasi-periodic (≈ 11 years) oscillations between two distinct states, which we call “active” and “quiet”, with extremely sharp onset and termination. The ratio of time spent in the active vs. quiet states ranges from 1.8 to 1.4 for Cycles 21 to 23, Cycle 23 having the longest quiet period. It has been proposed that anomalous Cycle 23 resembles Cycle 4, which was

  4. Solar proton events during solar cycles 19, 20, and 21

    NASA Technical Reports Server (NTRS)

    Feynman, J.; Armstrong, T. P.; Dao-Gibner, L.; Silverman, S.

    1990-01-01

    Earlier studies based on a single solar cycle had resulted in a sharp division of events into 'ordinary' and 'anomalously large' events. Two such entirely separate distributions imply two entirely separate acceleration mechanisms, one common and the other very rare. The sharp division is neither required nor justified by this larger sample. Instead the event intensity forms a smooth distribution for intensities up to the largest observed implying that any second acceleration mechanism cannot be rare. Also, a clear bimodal variation of annual integrated flux with solar cycle phase but no statistically significant tendency for the large events to avoid sunspot maximum is found. There is almost no relation between the maximum sunspot number in a solar cycle and the solar cycle integrated flux. It is also found that for annual sunspot numbers greater than 35 there is no relation whatsoever between the annual sunspot numbers and annual integrated flux.

  5. Changes of solar extreme ultraviolet spectrum in solar cycle 24

    NASA Astrophysics Data System (ADS)

    Huang, Jianping; Hao, Yongqiang; Zhang, Donghe; Xiao, Zuo

    2016-07-01

    Following the extreme solar minimum during 2008-2009, solar activity keeps low in solar cycle 24 (SC24) and is making SC24 the weakest one of recent cycles. In this paper, using observations from Earth-orbiting satellites, we compare the solar extreme ultraviolet (EUV) irradiance between SC23 and SC24 and investigate the solar cycle change of linear dependence of EUV on the P ((F10.7 + F10.7A)/2) and Mg II core-to-wing ratio indices. The Bremen composite Mg II index is strongly correlated with P over the two solar cycles, while this is not the case for the Laboratory for Atmospheric and Space Physics (LASP) composite Mg II index, so we focus on the different dependence of EUV on the P and LASP Mg II indices. As a result we find that three coronal emissions (Fe XV at 28.4 nm and 41.7 nm and Fe XVI at 33.5 nm) brighten in SC24 relative to P; i.e., the magnitude of irradiance is higher than in SC23 at the same level of P. But relative to the LASP Mg II index, these emissions show no appreciable solar cycle differences. By contrast, the H I Lyman α at 121.6 nm dims in SC24 relative to the LASP Mg II but shows identical dependence on P in the two solar cycles. This result seems to contradict a well-accepted fact that chromospheric and transition region emissions are better represented by the Mg II index and coronal lines by F10.7. For the different solar cycle variability of EUV in SC24, whether it is caused by source changes on the Sun is still unclear, but we suggest that it needs to be considered in proxy modeling of the EUV irradiance and aeronomic studies.

  6. 19th JANNAF Safety and Environmental Protection Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Cocchiaro, J. E. (Editor); Becker, D. L. (Editor)

    2002-01-01

    This volume, the first of two volumes, is a compilation of 22 unclassified/unlimited technical papers presented at the 19th Joint Army-Navy-NASA-Air Force (JANNAF) Safety & Environmental Protection Subcommittee Meeting. The meeting was held 18-21 March 2002 at the Sheraton Colorado Springs Hotel, Colorado Springs, Colorado. Topics covered include green energetic materials and life cycle pollution prevention; space launch range safety; propellant/munitions demilitarization, recycling, and reuse: and environmental and occupational health aspects of propellants and energetic materials.

  7. Solar cycle changes in coronal holes and space weather cycles

    NASA Astrophysics Data System (ADS)

    Luhmann, J. G.; Li, Y.; Arge, C. N.; Gazis, P. R.; Ulrich, R.

    2002-08-01

    Potential field source surface models of the coronal magnetic field, based on Mt. Wilson Observatory synoptic magnetograms, are used to infer the coronal hole sources of low-heliolatitude solar wind over approximately the last three solar cycles. Related key parameters like interplanetary magnetic field and bulk velocity are also calculated. The results illustrate how the evolving contribution of the polar hole sources relative to that from low-latitude and midlatitude active region hole sources can explain solar magnetic field control of long-term interplanetary variations. In particular, the enduring consistent magnetogram record and continuous model displays produce a useful overview of the solar control of interplanetary cycles and trends that affect space weather.

  8. Science in the 19th-century zoo.

    PubMed

    Hochadel, Oliver

    2005-03-01

    The 19th century saw the advent of the modern zoological garden. The newly founded zoos not only claimed to educate and entertain their audiences, but also to serve science by providing direct access to exotic animals. However, reality did not live up to the promise of such rhetoric. The vast majority of biologists preferred to use dead bodies as the material for their morphological research. Nevertheless, there was still a strong interaction between the zoo and science. In the debate on Darwinism, the apes in the cage played a vital role.

  9. [Strength training at the beginning of the 19th century].

    PubMed

    Seignan, Gérard

    2015-01-01

    At the beginning of the 19th century, the therapies of strength had part task to revive vital energy and thus to restore the body forces. Under the method assigned with this objective, there were the baths, body exercises and a continuation of preservation recommended by hygiene. On a general level, the doctor had in hearth to harder the body and to make it robust and healthy. He is to the sick of the head could benefit from this care. Electrification made demonstration of its curative action and its interest to treat the languid state. Considered under this angle, strength could not be then the prerogative of the only muscles.

  10. The development of the dementia concept in 19th century.

    PubMed

    Caixeta, Leonardo; Costa, Jean Newton Lima; Vilela, Ana Caroline Marques; Nóbrega, Magno da

    2014-07-01

    The dementia concept has been reformulated through its history and the 19th century was remarkable in the construction of this concept as we understand it today. Like other syndromes, much of the history of the dementia concept comes from the attempt to separate it from other nosological conditions, giving it a unique identity. The fundamental elements for the arising of the dementia modern concept were: a) correlation of the observed syndrome with organic-cerebral lesions; b) understanding of the irreversibility of the dementia evolution; c) its relation with human ageing; and d) the choice of the cognitive dysfunction as a clinical marker of the dementia concept.

  11. Examination of Solar Cycle Statistical Model and New Prediction of Solar Cycle 23

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Wilson, John W.

    2000-01-01

    Sunspot numbers in the current solar cycle 23 were estimated by using a statistical model with the accumulating cycle sunspot data based on the odd-even behavior of historical sunspot cycles from 1 to 22. Since cycle 23 has progressed and the accurate solar minimum occurrence has been defined, the statistical model is validated by comparing the previous prediction with the new measured sunspot number; the improved sunspot projection in short range of future time is made accordingly. The current cycle is expected to have a moderate level of activity. Errors of this model are shown to be self-correcting as cycle observations become available.

  12. OVERALL VIEW OF CEMETERY ENTRANCE GATE AND 19TH STREET APPROACH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    OVERALL VIEW OF CEMETERY ENTRANCE GATE AND 19TH STREET APPROACH, LOOKING INTO CEMETERY. VIEW TO NORTHEAST. - Baton Rouge National Cemetery, 220 North 19th Street, Baton Rouge, East Baton Rouge Parish, LA

  13. REAR AND SOUTH SIDE OF MAINTENANCE BUILDING FROM ACROSS 19TH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    REAR AND SOUTH SIDE OF MAINTENANCE BUILDING FROM ACROSS 19TH STREET, WITH ENCLOSURE WALL IN FOREGROUND. VIEW TO NORTHEAST. - Baton Rouge National Cemetery, 220 North 19th Street, Baton Rouge, East Baton Rouge Parish, LA

  14. Solar cycle modulation of Southern Annular Mode

    NASA Astrophysics Data System (ADS)

    Kuroda, Yuhji

    2016-04-01

    Climate is known to be affected by various factors, including oceanic changes and volcanic eruptions. 11-year solar cycle change is one of such important factors. Observational analysis shows that the winter-mean North Atlantic Oscillation (NAO) and late-winter/spring Southern Annular Mode (SAM) show structural modulation associated with 11-year solar cycle. In fact, these signals tend to extend from surface to upper stratosphere and persistent longer period only in the High Solar (HS) years. In the present study, we used 35-year record of ERA-Interim reanalysis data and performed wave-energy and momentum analysis on the solar-cycle modulation of the SAM to examine key factors to create such solar-SAM relationship. It is found that enhanced wave-mean flow interaction tends to take place in the middle stratosphere in association with enhanced energy input from diabatic heating on September only in HS years. The result suggests atmospheric and solar conditions on September are keys to create solar-SAM relationship.

  15. Nostalgia in the Army (17th-19th Centuries).

    PubMed

    Battesti, Michèle

    2016-01-01

    People died from nostalgia in the army in the 17th-19th centuries. The term 'nostalgia', created by the doctor Johannes Hofer (1669-1752), from Mulhouse, came from the Germanic Heimweh, or 'homesickness'. It affected the young people enrolled in the army, such as Swiss mercenaries. Longing for their native land, they were consumed by an ongoing desire to return home. If it was impossible to do so, they sank into 'a sadness accompanied with insomnia, anorexia and other unpleasant symptoms' that could lead to death. Nostalgia became classified as a disease during the last quarter of the 18th century and ravaged the French army during the Revolution and the Napoleonic wars. However, as soon as the wars ended, it ceased to exist in the army (except the colonial army). It was removed from the nosology in the first half of the 19th century. Rapidly explained as an example of a misdiagnosis or a confusion between 'connection and cause', nostalgia needs to be assessed in regard to the medical debate between 'alienists' and 'organicists'. Creating much concern, nostalgia needs to be considered in the historical context of a society destabilized by modernity, with some individuals uprooted by the sudden transition from civil society to military life. It raises questions about the role that the army played in the creation of the French national union. Nostalgia may have also covered psychic traumatisms later designated as combat fatigue, war neurosis, or post-traumatic stress disorder.

  16. Nostalgia in the Army (17th-19th Centuries).

    PubMed

    Battesti, Michèle

    2016-01-01

    People died from nostalgia in the army in the 17th-19th centuries. The term 'nostalgia', created by the doctor Johannes Hofer (1669-1752), from Mulhouse, came from the Germanic Heimweh, or 'homesickness'. It affected the young people enrolled in the army, such as Swiss mercenaries. Longing for their native land, they were consumed by an ongoing desire to return home. If it was impossible to do so, they sank into 'a sadness accompanied with insomnia, anorexia and other unpleasant symptoms' that could lead to death. Nostalgia became classified as a disease during the last quarter of the 18th century and ravaged the French army during the Revolution and the Napoleonic wars. However, as soon as the wars ended, it ceased to exist in the army (except the colonial army). It was removed from the nosology in the first half of the 19th century. Rapidly explained as an example of a misdiagnosis or a confusion between 'connection and cause', nostalgia needs to be assessed in regard to the medical debate between 'alienists' and 'organicists'. Creating much concern, nostalgia needs to be considered in the historical context of a society destabilized by modernity, with some individuals uprooted by the sudden transition from civil society to military life. It raises questions about the role that the army played in the creation of the French national union. Nostalgia may have also covered psychic traumatisms later designated as combat fatigue, war neurosis, or post-traumatic stress disorder. PMID:27035922

  17. Music therapy in the 19th century America.

    PubMed

    Davis, W B

    1987-01-01

    The history of music therapy in the United States has not been thoroughly investigated and documented. The few sources containing information on the historical uses of music in medicine concentrate primarily on 20th century practices, while virtually omitting 19th century contributions to the field. The purpose of this study was to analyze elected music therapy literature that appeared in 19th century medical journals and dissertations. The articles found in these publications indicated interest during this time in advocating the use of music to provide the patient an alternate, more holistic approach to treatment. The dissemination of music therapy ideas occurred almost exclusively through these publications, which unfortunately resulted in very limited proliferation of the topic because of the nature of the audience (i.e.,primarily physicians). Nine articles were analyzed; the study was based on primary evidence located in medical journals and dissertations written between 1804 and 1899. The sources were located in a variety of bibliographies found in books, journals, dissertations, and theses.

  18. On solar cycle predictions and reconstructions

    NASA Astrophysics Data System (ADS)

    Brajša, R.; Wöhl, H.; Hanslmeier, A.; Verbanac, G.; Ruždjak, D.; Cliver, E.; Svalgaard, L.; Roth, M.

    2009-03-01

    Context: Generally, there are two procedures for solar cycle predictions: the empirical methods - statistical methods based on extrapolations and precursor methods - and methods based on dynamo models. Aims: The goal of the present analysis is to forecast the strength and epochs of the next solar cycle, to investigate proxies for grand solar minima and to reconstruct the relative sunspot number in the Maunder minimum. Methods: We calculate the asymmetry of the ascending and descending solar cycle phases (Method 1) and use this parameter as a proxy for solar activity on longer time scales. Further, we correlate the relative sunspot numbers in the epochs of solar activity minima and maxima (Method 2) and estimate the parameters of an autoregressive moving average model (ARMA, Method 3). Finally, the power spectrum of data obtained with the Method 1 is analysed and the Methods 1 and 3 are combined. Results: Signatures of the Maunder, Dalton and Gleissberg minima were found with Method 1. A period of about 70 years, somewhat shorter than the Gleissberg period was identified in the asymmetry data. The maximal smoothed monthly sunspot number during the Maunder minimum was reconstructed and found to be in the range 0-35 (Method 1). The estimated Wolf number (also called the relative sunspot number) of the next solar maximum is in the range 88-102 (Method 2). Method 3 predicts the next solar maximum between 2011 and 2012 and the next solar minimum for 2017. Also, it forecasts the relative sunspot number in the next maximum to be 90 ± 27. A combination of the Methods 1 and 3 gives for the next solar maximum relative sunspot numbers between 78 and 99. Conclusions: The asymmetry parameter provided by Method 1 is a good proxy for solar activity in the past, also in the periods for which no relative sunspot numbers are available. Our prediction for the next solar cycle No. 24 is that it will be weaker than the last cycle, No. 23. This prediction is based on various independent

  19. Solar Spectral Irradiance Changes During Cycle 24

    NASA Technical Reports Server (NTRS)

    Marchenko, Sergey; Deland, Matthew

    2014-01-01

    We use solar spectra obtained by the Ozone Monitoring Instrument (OMI) on board the Aura satellite to detect and follow long-term (years) and short-term (weeks) changes in the solar spectral irradiance (SSI) in the 265-500 nm spectral range. During solar Cycle 24, in the relatively line-free regions the SSI changed by approximately 0.6% +/- 0.2% around 265 nm. These changes gradually diminish to 0.15% +/- 0.20% at 500 nm. All strong spectral lines and blends, with the notable exception of the upper Balmer lines, vary in unison with the solar "continuum." Besides the lines with strong chromospheric components, the most involved species include Fe I blends and all prominent CH, NH, and CN spectral bands. Following the general trend seen in the solar "continuum," the variability of spectral lines also decreases toward longer wavelengths. The long-term solar cycle SSI changes are closely, to within the quoted 0.1%-0.2% uncertainties, matched by the appropriately adjusted short-term SSI variations derived from the 27 day rotational modulation cycles. This further strengthens and broadens the prevailing notion about the general scalability of the UV SSI variability to the emissivity changes in the Mg II 280 nm doublet on timescales from weeks to years. We also detect subtle deviations from this general rule: the prominent spectral lines and blends at lambda approximately or greater than 350 nm show slightly more pronounced 27 day SSI changes when compared to the long-term (years) trends. We merge the solar data from Cycle 21 with the current Cycle 24 OMI and GOME-2 observations and provide normalized SSI variations for the 170-795 nm spectral region.

  20. Solar spectral irradiance changes during cycle 24

    SciTech Connect

    Marchenko, S. V.; DeLand, M. T.

    2014-07-10

    We use solar spectra obtained by the Ozone Monitoring Instrument (OMI) on board the Aura satellite to detect and follow long-term (years) and short-term (weeks) changes in the solar spectral irradiance (SSI) in the 265-500 nm spectral range. During solar Cycle 24, in the relatively line-free regions the SSI changed by ∼0.6% ± 0.2% around 265 nm. These changes gradually diminish to 0.15% ± 0.20% at 500 nm. All strong spectral lines and blends, with the notable exception of the upper Balmer lines, vary in unison with the solar 'continuum'. Besides the lines with strong chromospheric components, the most involved species include Fe I blends and all prominent CH, NH, and CN spectral bands. Following the general trend seen in the solar 'continuum', the variability of spectral lines also decreases toward longer wavelengths. The long-term solar cycle SSI changes are closely, to within the quoted 0.1%-0.2% uncertainties, matched by the appropriately adjusted short-term SSI variations derived from the 27 day rotational modulation cycles. This further strengthens and broadens the prevailing notion about the general scalability of the UV SSI variability to the emissivity changes in the Mg II 280 nm doublet on timescales from weeks to years. We also detect subtle deviations from this general rule: the prominent spectral lines and blends at λ ≳ 350 nm show slightly more pronounced 27 day SSI changes when compared to the long-term (years) trends. We merge the solar data from Cycle 21 with the current Cycle 24 OMI and GOME-2 observations and provide normalized SSI variations for the 170-795 nm spectral region.

  1. Prediction Methods in Solar Sunspots Cycles

    PubMed Central

    Ng, Kim Kwee

    2016-01-01

    An understanding of the Ohl’s Precursor Method, which is used to predict the upcoming sunspots activity, is presented by employing a simplified movable divided-blocks diagram. Using a new approach, the total number of sunspots in a solar cycle and the maximum averaged monthly sunspots number Rz(max) are both shown to be statistically related to the geomagnetic activity index in the prior solar cycle. The correlation factors are significant and they are respectively found to be 0.91 ± 0.13 and 0.85 ± 0.17. The projected result is consistent with the current observation of solar cycle 24 which appears to have attained at least Rz(max) at 78.7 ± 11.7 in March 2014. Moreover, in a statistical study of the time-delayed solar events, the average time between the peak in the monthly geomagnetic index and the peak in the monthly sunspots numbers in the succeeding ascending phase of the sunspot activity is found to be 57.6 ± 3.1 months. The statistically determined time-delayed interval confirms earlier observational results by others that the Sun’s electromagnetic dipole is moving toward the Sun’s Equator during a solar cycle. PMID:26868269

  2. Prediction Methods in Solar Sunspots Cycles

    NASA Astrophysics Data System (ADS)

    Ng, Kim Kwee

    2016-02-01

    An understanding of the Ohl’s Precursor Method, which is used to predict the upcoming sunspots activity, is presented by employing a simplified movable divided-blocks diagram. Using a new approach, the total number of sunspots in a solar cycle and the maximum averaged monthly sunspots number Rz(max) are both shown to be statistically related to the geomagnetic activity index in the prior solar cycle. The correlation factors are significant and they are respectively found to be 0.91 ± 0.13 and 0.85 ± 0.17. The projected result is consistent with the current observation of solar cycle 24 which appears to have attained at least Rz(max) at 78.7 ± 11.7 in March 2014. Moreover, in a statistical study of the time-delayed solar events, the average time between the peak in the monthly geomagnetic index and the peak in the monthly sunspots numbers in the succeeding ascending phase of the sunspot activity is found to be 57.6 ± 3.1 months. The statistically determined time-delayed interval confirms earlier observational results by others that the Sun’s electromagnetic dipole is moving toward the Sun’s Equator during a solar cycle.

  3. THE BIMODAL STRUCTURE OF THE SOLAR CYCLE

    SciTech Connect

    Du, Z. L.

    2015-05-01

    Some properties of the 11 yr solar cycle can be explained by the current solar dynamo models. However, some other features remain not well understood such as the asymmetry of the cycle, the double-peaked structure, and the “Waldmeier effect” that a stronger cycle tends to have less rise time and a shorter cycle length. We speculate that the solar cycle is governed by a bi-dynamo model forming two stochastic processes depicted by a bimodal Gaussian function with a time gap of about 2 yr, from which the above features can be reasonably explained. The first one describes the main properties of the cycle dominated by the current solar dynamo models, and the second one occurs either in the rising phase as a short weak explosive perturbation or in the declining phase as a long stochastic perturbation. The above function is the best one selected from several in terms of the Akaike information criterion. Through analyzing different distributions, one might speculate about the dominant physical process inside the convection zone. The secondary (main) process is found to be closely associated with complicated (simple) active ranges. In effect, the bi-dynamo model is a reduced form of a multi-dynamo model, which could occur from the base of the convection zone through its envelope and from low to high heliographic latitude, reflecting the active belts in the convection zone. These results are insensitive to the hemispheric asymmetry, smoothing filters, and distribution functions selected and are expected to be helpful in understanding the formation of solar and stellar cycles.

  4. Solar Cycle Variation of CMEs and CIRs

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.

    2011-01-01

    Coronal mass ejections (CMEs) and high-speed solar wind streams (HSS) are two solar phenomena that produce large-scale structures in the interplanetary (IP) medium. CMEs evolve into interplanetary CMEs (ICMEs) and the HSS result in corotating interaction regions (CIRs) when they interact with preceding slow solar wind. CMEs and CIRs originate from closed (active region and filament region) and open (corona) hole) magnetic field regions on the Sun, respectively. These two types of mass emissions from the Sun are responsible for the largest effects on the heliosphere, particularly on Earth's space environment. This paper discussed how these structures and their solar sources vary with the solar cycle and the consequent changes in the geospace impact.

  5. [The technicalization of medicine in the 19th century].

    PubMed

    Olsén, J E

    2001-01-01

    The paper focuses on the role that instruments played in the medical discourse of the 19th century. Towards the end of the century, instruments had imbued the medical sciences to such an extent that the situation soon was compared to the vernacular confusion of the biblical tower of Babel. Whereas the autonomical recordings of laboratory apparatus, vouched for guarantee against biased test results, clinicians and general practitioners were finding it difficult to incorporate the new techniques into their daily routines. A tension between the instrument as invention, moulded to fit a particular series of experiments, and the instrument as a reproducible item, was inevitable. Hence, the unification of the science and practice of medicine, became an important topic at the international medical meetings of the late 19th century. Seen in the light of the industrialization and urbanization of occidental culture and society, the instrumentation of medicine entailed a number of significant issues which hinged on the relationship between the biological destiny of man and the artificial wonders of technology. Grand metaphors like the organic machine and the human motor, did not only signal a scientific preoccupation with the shortcomings of the living organism as opposed to the perfection of the machine, but also indicated closer ties between the human body and technology at large. In a certain sense, medical instruments, along with apparatuses such as the camera, the steam-engine, the telegraph, the phonograph and the cinematograph, offered a new set-up of codes with which the body and its functions could be reinterpreted. In this respect, the late nineteenth-century strive for the standardisation and unification of medical instruments, was not irreconcilable with the notion of the l'homme moyen, as conceived, for example, in the work of the Belgian mathematician Adolphe Quetelet. The paper outlines the span of medical measuring devices, dating from the sphygmometer of

  6. [The technicalization of medicine in the 19th century].

    PubMed

    Olsén, J E

    2001-01-01

    The paper focuses on the role that instruments played in the medical discourse of the 19th century. Towards the end of the century, instruments had imbued the medical sciences to such an extent that the situation soon was compared to the vernacular confusion of the biblical tower of Babel. Whereas the autonomical recordings of laboratory apparatus, vouched for guarantee against biased test results, clinicians and general practitioners were finding it difficult to incorporate the new techniques into their daily routines. A tension between the instrument as invention, moulded to fit a particular series of experiments, and the instrument as a reproducible item, was inevitable. Hence, the unification of the science and practice of medicine, became an important topic at the international medical meetings of the late 19th century. Seen in the light of the industrialization and urbanization of occidental culture and society, the instrumentation of medicine entailed a number of significant issues which hinged on the relationship between the biological destiny of man and the artificial wonders of technology. Grand metaphors like the organic machine and the human motor, did not only signal a scientific preoccupation with the shortcomings of the living organism as opposed to the perfection of the machine, but also indicated closer ties between the human body and technology at large. In a certain sense, medical instruments, along with apparatuses such as the camera, the steam-engine, the telegraph, the phonograph and the cinematograph, offered a new set-up of codes with which the body and its functions could be reinterpreted. In this respect, the late nineteenth-century strive for the standardisation and unification of medical instruments, was not irreconcilable with the notion of the l'homme moyen, as conceived, for example, in the work of the Belgian mathematician Adolphe Quetelet. The paper outlines the span of medical measuring devices, dating from the sphygmometer of

  7. Changes of solar extreme ultraviolet spectrum in solar cycle 24

    NASA Astrophysics Data System (ADS)

    Hao, Yongqiang; Zhang, Donghe; Xiao, Zuo; Huang, Jianping

    2016-07-01

    Following the extreme solar minimum during 2008 - 2009, solar activity keeps low in solar cycle 24 (SC24) and is making SC24 the weakest one of recent cycles. In this paper, we compare the solar EUV spectral irradiance between SC23 and SC24, using the measurements by the Solar EUV Experiment (SEE) on the Thermospheric Ionospheric Mesospheric Energy and Dynamics (TIMED) spacecraft. The EUV spectrum varies with solar activity, and is in general a linear function of a proxy index P= (F10.7 + F10.7A)/2. However, we find the slope of this function, i.e., the change rate of irradiance at each wavelength with P, differs between SC23 and SC24. Consequently, at a given P level, the irradiance in SC24 is higher at wavelength of 30 - 50 nm, but lower at 60 - 120 nm and longward of 140 nm; the inter-cycle variation of EUV irradiance at some wavelengths can be 30 - 40% in absolute flux. We further examine 38 most intense emission lines and find that, taking P as a reference, most of the bright coronal lines get stronger in SC24 and, by contrast, those from the chromosphere and transition region have less variability in SC24. We therefore suggest that, the empirical relation between solar EUV and P, which is derived from observations in previous solar cycles, may not adapt to SC24. The changes in EUV spectrum need to be considered in the models for aeronomic study, especially those using F10.7 index as an input parameter.

  8. Cosmic ray modulation over a solar cycle.

    NASA Astrophysics Data System (ADS)

    Ferreira, Stefan; Manuel, Rex; Potgieter, Marius

    2016-07-01

    The time-dependent modulation of galactic cosmic rays in the heliosphere is studied over different polarity cycles by computing 2.5 GV proton intensities using a two-dimensional, time-dependent modulationmodel. By incorporating recent theoretical advances in the relevant transport parameters in the model, we showed in previous work that this approach gave realistic computed intensities over a solar cycle. New in this work is that a time dependence of the solar wind termination shock (TS) position is implemented in our model to study the effect of a dynamic inner heliosheath thickness (the region between the TS and heliopause) on the solar modulation of galactic cosmic rays. The study reveals that changes in the inner heliosheath thickness, arising from a time-dependent shock position, does affect cosmic-ray intensities everywhere in the heliosphere over a solar cycle, with the smallest effect in the innermost heliosphere. A time-dependent TS position causes a phase difference between the solar activity periods and the corresponding intensity periods. The maximum intensities in response to a solarminimum activity period are found to be dependent on the time-dependent TS profile. It is found that changing the width of the inner heliosheath with time over a solar cycle can shift the time of when the maximum or minimum cosmic-ray intensities occur at various distances throughout the heliosphere, but more significantly in the outer heliosphere. The time-dependent extent of the inner heliosheath, as affected by solar activity conditions, is thus an additional time-dependent factor to be considered in the long-term modulation of cosmic rays.

  9. Sources of solar wind over the solar activity cycle

    PubMed Central

    Poletto, Giannina

    2012-01-01

    Fast solar wind has been recognized, about 40 years ago, to originate in polar coronal holes (CHs), that, since then, have been identified with sources of recurrent high speed wind streams. As of today, however, there is no general consensus about whether there are, within CHs, preferential locations where the solar wind is accelerated. Knowledge of slow wind sources is far from complete as well. Slow wind observed in situ can be traced back to its solar source by backward extrapolation of magnetic fields whose field lines are streamlines of the outflowing plasma. However, this technique often has not the necessary precision for an indisputable identification of the region where wind originates. As the Sun progresses through its activity cycle, different wind sources prevail and contribute to filling the heliosphere. Our present knowledge of different wind sources is here summarized. Also, a Section addresses the problem of wind acceleration in the low corona, as inferred from an analysis of UV data, and illustrates changes between fast and slow wind profiles and possible signatures of changes along the solar cycle. A brief reference to recent work about the deep roots of solar wind and their changes over different solar cycles concludes the review. PMID:25685421

  10. Sources of solar wind over the solar activity cycle.

    PubMed

    Poletto, Giannina

    2013-05-01

    Fast solar wind has been recognized, about 40 years ago, to originate in polar coronal holes (CHs), that, since then, have been identified with sources of recurrent high speed wind streams. As of today, however, there is no general consensus about whether there are, within CHs, preferential locations where the solar wind is accelerated. Knowledge of slow wind sources is far from complete as well. Slow wind observed in situ can be traced back to its solar source by backward extrapolation of magnetic fields whose field lines are streamlines of the outflowing plasma. However, this technique often has not the necessary precision for an indisputable identification of the region where wind originates. As the Sun progresses through its activity cycle, different wind sources prevail and contribute to filling the heliosphere. Our present knowledge of different wind sources is here summarized. Also, a Section addresses the problem of wind acceleration in the low corona, as inferred from an analysis of UV data, and illustrates changes between fast and slow wind profiles and possible signatures of changes along the solar cycle. A brief reference to recent work about the deep roots of solar wind and their changes over different solar cycles concludes the review.

  11. Statistical Projection of Solar Cycle 24 for the Exposure Estimates

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee; Wilson, John W.; Cucinotta, Francis A.

    2011-01-01

    A solar cycle statistical model has been developed based on the accumulating cycle sunspot data to estimate future levels of the solar cycle activity. Since the current solar cycle 24 has progressed about three years, the cycle activity levels are estimated with an accurately defined solar minimum 24. Then, solar cycle 24 is projected with the cycle activity levels using the statistical model. The projection of solar cycle 24 is then coupled to space related quantities of interest to radiation protection, because the interplanetary plasma and radiation fields are modulated by the degree of disturbance in the solar surface and the radiation doses received by astronauts in interplanetary space are likewise influenced. The resultant projection of solar cycle 24 provides a basis for estimating exposure in future space missions, and projection errors can be corrected as the cycle progresses and observations become available because this model is shown to be self-correcting.

  12. Solar cycle variation in UV solar spectral irradiance

    NASA Astrophysics Data System (ADS)

    Leng Yeo, Kok; Krivova, Natalie; Solanki, Sami K.

    2015-08-01

    Solar spectral irradiance, SSI, in the UV has been measured from space, almost without interruption, since 1978. This is accompanied by the development of models aimed at reconstructing SSI by relating its variability to solar magnetic activity. The various satellite records and model reconstructions differ significantly in terms of the variation over the solar cycle, with the consequence that their application to climate models yield qualitatively different results. Here, we highlight the key discrepancies between available records and reconstructions, and discuss the possible underlying causes.

  13. Cholera in Haiti and Other Caribbean Regions, 19th Century

    PubMed Central

    Szabo, Victoria

    2011-01-01

    Medical journals and other sources do not show evidence that cholera occurred in Haiti before 2010, despite the devastating effect of this disease in the Caribbean region in the 19th century. Cholera occurred in Cuba in 1833–1834; in Jamaica, Cuba, Puerto Rico, St. Thomas, St. Lucia, St. Kitts, Nevis, Trinidad, the Bahamas, St. Vincent, Granada, Anguilla, St. John, Tortola, the Turks and Caicos, the Grenadines (Carriacou and Petite Martinique), and possibly Antigua in 1850–1856; and in Guadeloupe, Cuba, St. Thomas, the Dominican Republic, Dominica, Martinique, and Marie Galante in 1865–1872. Conditions associated with slavery and colonial military control were absent in independent Haiti. Clustered populations, regular influx of new persons, and close quarters of barracks living contributed to spread of cholera in other Caribbean locations. We provide historical accounts of the presence and spread of cholera epidemics in Caribbean islands. PMID:22099117

  14. JANNAF 19th Propulsion Systems Hazards Subcommittee Meeting. Volume 1

    NASA Technical Reports Server (NTRS)

    Cocchiaro, James E. (Editor); Kuckels, Melanie C. (Editor)

    2000-01-01

    This volume, the first of two volumes is a compilation of 25 unclassified/unlimited-distribution technical papers presented at the Joint Army-Navy-NASA-Air Force (JANNAF) 19th Propulsion Systems Hazards Subcommittee (PSHS) meeting held jointly with the 37th Combustion Subcommittee (CS) and 25th Airbreathing Propulsion Subcommittee (APS), and 1st Modeling and Simulation Subcommittee (MSS) meetings. The meeting was held 13-17 November 2000 at the Naval Postgraduate School and Hyatt Regency Hotel, Monterey, California. Topics covered at the PSHS meeting include: impact and thermal vulnerability of gun propellants; thermal decomposition and cookoff behavior of energetic materials; violent reaction and detonation phenomena of solid energetic materials subjected to shock and impact loading; and hazard classification, and insensitive munitions testing of propellants and propulsion systems.

  15. Study of the Solar Cycle from Space

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The objectives of and benefits to be derived from a program of solar cycle research are discussed with emphasis on the role space observations will play in this venture. The strategy to be employed in the coming decade is considered as well as crucial missions, experiments, and the theoretical advances required.

  16. Geomagnetism during solar cycle 23: Characteristics.

    PubMed

    Zerbo, Jean-Louis; Amory-Mazaudier, Christine; Ouattara, Frédéric

    2013-05-01

    On the basis of more than 48 years of morphological analysis of yearly and monthly values of the sunspot number, the aa index, the solar wind speed and interplanetary magnetic field, we point out the particularities of geomagnetic activity during the period 1996-2009. We especially investigate the last cycle 23 and the long minimum which followed it. During this period, the lowest values of the yearly averaged IMF (3 nT) and yearly averaged solar wind speed (364 km/s) are recorded in 1996, and 2009 respectively. The year 2003 shows itself particular by recording the highest value of the averaged solar wind (568 km/s), associated to the highest value of the yearly averaged aa index (37 nT). We also find that observations during the year 2003 seem to be related to several coronal holes which are known to generate high-speed wind stream. From the long time (more than one century) study of solar variability, the present period is similar to the beginning of twentieth century. We especially present the morphological features of solar cycle 23 which is followed by a deep solar minimum. PMID:25685427

  17. Ionospheric criticial frequencies and solar cycle effects

    NASA Astrophysics Data System (ADS)

    Kilcik, Ali; Ozguc, Atila; Rozelot, Jean Pierre; Yiǧit, Erdal; Elias, Ana; Donmez, Burcin; Yurchyshyn, Vasyl

    2016-07-01

    The long term solar activity dependencies of ionospheric F1 and F2 regions critical frequencies (foF1 and foF2) are investigated observationally for the last four solar cycles (1976-2015). We here show that the ionospheric F1 and F2 regions have different solar activity dependencies in terms of the sunspot group (SG) numbers: F1 region critical frequency (foF1) peaks at the same time with small SG numbers, while the foF2 reaches its maximum at the same time with the large SG numbers especially during the solar cycle 23. Thus, we may conclude that the sensitivities of ionospheric F1 and F2 region critical frequencies to sunspot group (SG) numbers are associated with different physical processes that are yet to be investigated in detail. Such new results provide further evidence that the two ionospheric regions have different responses to the solar activity. We also analyzed short term oscillatory behavior of ionospheric critical frequencies and found some solar signatures.

  18. Geomagnetism during solar cycle 23: Characteristics

    PubMed Central

    Zerbo, Jean-Louis; Amory-Mazaudier, Christine; Ouattara, Frédéric

    2012-01-01

    On the basis of more than 48 years of morphological analysis of yearly and monthly values of the sunspot number, the aa index, the solar wind speed and interplanetary magnetic field, we point out the particularities of geomagnetic activity during the period 1996–2009. We especially investigate the last cycle 23 and the long minimum which followed it. During this period, the lowest values of the yearly averaged IMF (3 nT) and yearly averaged solar wind speed (364 km/s) are recorded in 1996, and 2009 respectively. The year 2003 shows itself particular by recording the highest value of the averaged solar wind (568 km/s), associated to the highest value of the yearly averaged aa index (37 nT). We also find that observations during the year 2003 seem to be related to several coronal holes which are known to generate high-speed wind stream. From the long time (more than one century) study of solar variability, the present period is similar to the beginning of twentieth century. We especially present the morphological features of solar cycle 23 which is followed by a deep solar minimum. PMID:25685427

  19. Influence of Solar Cycles on Earthquakes

    NASA Astrophysics Data System (ADS)

    Tavares, M.

    2011-12-01

    This research inspects possible influence of solar cycles on earthquakes through of statistical analyses. We also discussed the mechanism that would drive the occurrence of increasing of earthquakes during solar maxima. The study was based on worldwide earthquakes events during approximately four hundred years (1600-2010). The increase of earthquakes events followed the Maxima of Solar cycle, and also depends on the tectonic plate location. From 1600 until 1645 events increased during the Maxima in some of the tectonic plates as Pacific, Arabian and South America. The earthquakes analyzed during two grand solar minima, the Maunder (1645-1720) and the Dalton (1790-1820) showed a decrease in the number of earthquakes and the solar activity. It was observed during these minima a significant number of events at specific geological features. After the last minima (Dalton) the earthquakes pattern increased with solar maxima. The calculations showed that events increasing during solar maxima most in the Pacific, South America or Arabian until 1900. Since there were few records during these three centuries we needed additional analysis on modern data. We took the last four solar cycles events (1950-2010) and made similar calculations. The results agreed with the former calculations. It might be that the mechanism for the Sun-Earth connection relies on the solar wind speed. In both records (1600-1900) and (1950-2010) the results showed a significant increase in earthquakes events in some of the tectonic plates linked to solar maxima. The Solar wind energy striking the Earth's magnetosphere affects the entire environment because the pressure on the region increases and the magnetosphere shrinks sometimes four Earth's radii. This sudden compression causes earthquakes in specific plates. During the times of solar minima the pressure from the solar wind on the earth decreases, then the magnetosphere expands and earthquakes happen in a different pattern according to the

  20. Solar cycle modulation of Titan's ionosphere

    NASA Astrophysics Data System (ADS)

    Edberg, N. J. T.; Andrews, D. J.; Shebanits, O.; Ågren, K.; Wahlund, J.-E.; Opgenoorth, H. J.; Cravens, T. E.; Girazian, Z.

    2013-08-01

    During the six Cassini Titan flybys T83-T88 (May 2012 to November 2012) the electron density in the ionospheric peak region, as measured by the radio and plasma wave science instrument/Langmuir probe, has increased significantly, by 15-30%, compared to previous average. These measurements suggest that a long‒term change has occurred in the ionosphere of Titan, likely caused by the rise to the new solar maximum with increased EUV fluxes. We compare measurements from TA, TB, and T5, from the declining phase of solar cycle 23 to the recent T83-T88 measurements during cycle 24, since the solar irradiances from those two intervals are comparable. The peak electron densities normalized to a common solar zenith angle Nnorm from those two groups of flybys are comparable but increased compared to the solar minimum flybys (T16-T71). The integrated solar irradiance over the wavelengths 1-80nm, i.e., the solar energy flux, Fe, correlates well with the observed ionospheric peak density values. Chapman layer theory predicts that Nnorm∝Fek, with k=0.5. We find observationally that the exponent k=0.54±0.18. Hence, the observations are in good agreement with theory despite the fact that many assumptions in Chapman theory are violated. This is also in good agreement with a similar study by Girazian and Withers (2013) on the ionosphere of Mars. We use this power law to estimate the peak electron density at the subsolar point of Titan during solar maximum conditions and find it to be about 6500cm-3, i.e., 85-160% more than has been measured during the entire Cassini mission.

  1. Ozone depletion during solar proton events in solar cycle 21

    NASA Technical Reports Server (NTRS)

    Mcpeters, R. D.; Jackman, C. H.

    1985-01-01

    Ozone profile data from the Solar Backscattered Ultraviolet Instrument on Nimbus 7 from 1979 to the present and clear cases of ozone destruction associated with five sudden proton events (SPEs) on June 7, 1979, August 21, 1979, October 13-14, 1981, July 13, 1982, and December 8, 1982 are found. During the SPE on July 13, 1982, the largest of this solar cycle, no depletion at all at 45 km is observed, but there is a 15 percent ozone depletion at 50 km increasing to 27 percent at 55 km, all at a solar zenith angle of 85 deg. A strong variation of the observed depletion with solar zenith angle is found, with maximum depletion occurring at the largest zenith angles (near 85 deg) decreasing to near zero for angles below about 70 deg. The observed depletion is short lived, disappearing within hours of the end of the SPE.

  2. Distinguishing Solar Cycle Effects in Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Aplin, K. L.; Harrison, R. G.

    2008-12-01

    As solar radiation decreases with distance from the Sun, other sources of energy, such as ionization from galactic cosmic rays (GCR), assume a greater relative importance than at the terrestrial planets. Charged particle effects could therefore be more relevant to the formation of clouds and haze at the outer planets. The long-term solar modulation of Neptune's albedo is thought to be caused by either ion-induced nucleation of cloud-forming particles, or ultraviolet (UV) radiation effects on the colour of the clouds. On the basis of the 11 year solar cycle, the statistical evidence was slightly in favour of the UV mechanism, however distinguishing unambiguously between the two mechanisms will require more than the solar cycle variation alone. A 1.68 year quasi-periodicity, uniquely present at some times from heliospheric modulation of GCR, has previously been used to discriminate between solar UV and GCR effects in terrestrial data. The cosmic ray proton monitor data from both the Voyager spacecraft show this 1.68 year modulation during the 1980s when the spacecraft were close to the outer planets, indicating the possibility for applying a similar technique as far out as Neptune.

  3. Forecasting Solar Cycle 24 using the relationship between cycle length and maximum sunspot number

    NASA Astrophysics Data System (ADS)

    Watari, S.

    2008-12-01

    The parameters characterizing a solar cycle are its length and its maximum sunspot number. There is a good negative correlation (correlation coefficient is -0.661) between the length of a solar cycle and the maximum monthly smoothed sunspot number of the next cycle. This suggests that the length is an important parameter in determining the variations of solar activity. Using this relationship, I forecast lower solar activity in Cycle 24 than in Cycle 23.

  4. Coronal activity cycles in solar analog stars

    NASA Astrophysics Data System (ADS)

    Favata, Fabio

    2013-10-01

    We propose continuation into AO13 of the ongoing long-term program for the monitoring of coronal cycles in a sample of five solar-type stars in three stellar systems. The targets have been monitored continuously since AO1, yielding the first unambiguous evidence of cyclic behavior in the X-ray emission from the coronae of cool stars. Thanks to the long-term monitoring our program is starting to show evidence of the complex behavior of stellar cycles, with significant cycle-to-cycle variability becoming apparent. The observations requested in AO-13 will allow us to capitalize on our long-term investment of XMM-Newton observing time and to continue assembling a unique long-term data set that is likely to remain unmatched for a long time.

  5. Faces and Photography in 19th-Century Visual Science.

    PubMed

    Wade, Nicholas J

    2016-09-01

    Reading faces for identity, character, and expression is as old as humanity but representing these states is relatively recent. From the 16th century, physiognomists classified character in terms of both facial form and represented the types graphically. Darwin distinguished between physiognomy (which concerned static features reflecting character) and expression (which was dynamic and reflected emotions). Artists represented personality, pleasure, and pain in their paintings and drawings, but the scientific study of faces was revolutionized by photography in the 19th century. Rather than relying on artistic abstractions of fleeting facial expressions, scientists photographed what the eye could not discriminate. Photography was applied first to stereoscopic portraiture (by Wheatstone) then to the study of facial expressions (by Duchenne) and to identity (by Galton and Bertillon). Photography opened new methods for investigating face perception, most markedly with Galton's composites derived from combining aligned photographs of many sitters. In the same decade (1870s), Kühne took the process of photography as a model for the chemical action of light in the retina. These developments and their developers are described and fixed in time, but the ideas they initiated have proved impossible to stop. PMID:27146124

  6. Naming and Necessity: Sherborn's Context in the 19(th) Century.

    PubMed

    McOuat, Gordon

    2016-01-01

    By the late 19(th) Century, storms plaguing early Victorian systematics and nomenclature seemed to have abated. Vociferous disputes over radical renaming, the world-shaking clash of all-encompassing procrustean systems, struggles over centres of authority, and the issues of language and meaning had now been settled by the institution of a stable imperial museum and its catalogues, a set of rules for the naming of zoological objects, and a new professional class of zoologists. Yet, for all that tranquillity, the disputes simmered below the surface, re-emerging as bitter struggles over synonyms, trinomials, the subspecies category, the looming issues of the philosophy of scientific language, and the aggressive new American style of field biology - all pressed in upon the received practice of naming and classifying organisms and the threat of anarchy. In the midst rose an index. This paper will explore the context of CD Sherborn's Index Animalium and those looming problems and issues which a laborious and comprehensive "index of nature" was meant to solve.

  7. [Origin of animal experimentation legislation in the 19th century].

    PubMed

    Pocard, M

    1999-01-01

    The first legislation in the world, designed to protect animals used in research, was passed in England in 1876, and is still in force today. It is one of the strictest in Europe. At the same period, France had no such law, and was the country conducting the greatest amount of animal experimentation. Comparing, these two countries, in the middle of the 19th century, can account for this difference. The most important difference seems to be related to the theological question: are animals endowed with a soul? Saint Augustine, claimed, in the 4th century, perhaps because of an experiment with the centipede, that animals do not have a soul. In the 17th century, René Descartes, using a different philosophical system, reached a similar conclusion, in France. On the other hand, under the influence of Charles Darwin, England rejected the Roman Catholic conclusion, about the soul of animals. The industrial revolution, occurring earlier in England than in France, also changed the society, developing urban areas, where people were cut off from rural life and changing human relationships with animals. The industrial revolution enabled the development of the press, giving impetus to public opinion. These facts, combined with a caution of science, which was more developed in England than in France, brought about the first important "anti-doctor" campaign.

  8. Laser cleaning of 19th century Congo rattan mats

    NASA Astrophysics Data System (ADS)

    Carmona, N.; Oujja, M.; Roemich, H.; Castillejo, M.

    2011-09-01

    There is a growing interest by art conservators for laser cleaning of organic materials, such as wooden artworks, paper and textiles, since traditional cleaning with solvents can be a source of further decay and mechanical cleaning may be too abrasive for sensitive fibers. In this work we present a successful laser cleaning approach for 19th century rattan mats from the Brooklyn Museum collection of African Art, now part of the study collection at the Conservation Center in New York. Tests were carried out using the fundamental (1064 nm) and second harmonic (532 nm) wavelength of a Q-switched Nd:YAG laser to measure threshold values both for surface damage and color changes for different types of rattan samples. The irradiated substrates were investigated by optical microscopy, scanning electron microscopy and by UV-vis spectroscopy in order to determine the efficiency of laser cleaning and to assess possible deterioration effects that may have occurred as a result of laser irradiation. The study showed that by using the laser emission at 532 nm, a wavelength for which photon energy is below the bond dissociation level of the main cellulosic compounds and the water absorption is negligible, it is possible to select a range of laser fluences to remove the black dust layer without damaging the rattan material.

  9. Colombian approaches to psychology in the 19th century.

    PubMed

    Oviedo, Gilberto Leonardo

    2012-11-01

    Colombian intellectuals of the 19th century widely consulted scientific psychology in regard to their political, religious, and educational interests. Colombian independence from Spain (1810) introduced the necessity of transforming the former subjects into illustrious citizens and members of a modern state. After independence, political liberals embraced Bentham's thesis of utilitarianism and the theories of sensibility, with a teaching style based in induction. Conservatives defended the Catholic tradition about the divine origin of the soul and used scholasticism as a model of teaching. A bipartisan coalition, the Regeneration, incorporated the ideas of modern psychology based on the principles of Thomistic thought (Neo-Thomism). The Neo-Thomists considered psychology as a science of the soul and debated physiological explanations of the mind. The conceptual advances of the period have been trivialized in historical accounts of psychology in Colombia, due to the emphasis on the institutionalization processes of the discipline in 1947. (PsycINFO Database Record (c) 2012 APA, all rights reserved). PMID:23397920

  10. Faces and Photography in 19th-Century Visual Science.

    PubMed

    Wade, Nicholas J

    2016-09-01

    Reading faces for identity, character, and expression is as old as humanity but representing these states is relatively recent. From the 16th century, physiognomists classified character in terms of both facial form and represented the types graphically. Darwin distinguished between physiognomy (which concerned static features reflecting character) and expression (which was dynamic and reflected emotions). Artists represented personality, pleasure, and pain in their paintings and drawings, but the scientific study of faces was revolutionized by photography in the 19th century. Rather than relying on artistic abstractions of fleeting facial expressions, scientists photographed what the eye could not discriminate. Photography was applied first to stereoscopic portraiture (by Wheatstone) then to the study of facial expressions (by Duchenne) and to identity (by Galton and Bertillon). Photography opened new methods for investigating face perception, most markedly with Galton's composites derived from combining aligned photographs of many sitters. In the same decade (1870s), Kühne took the process of photography as a model for the chemical action of light in the retina. These developments and their developers are described and fixed in time, but the ideas they initiated have proved impossible to stop.

  11. Austrian pharmacy in the 18 and 19th century.

    PubMed

    Kletter, Christa

    2010-01-01

    This overview reflects the extensive changes in the health care system which had significant effects on the apothecaryâs profession and education. In the 18(th) century Maria Theresia assigned Gerard van Swieten to modernize the medical curriculum and to work out reforms for health care. The resulting sanitary bill released in 1770 and amended in 1773 became effective for the whole empire and influenced greatly the apothecaryâs profession. The Viennese Medical Faculty continued to be the supervisory body for the apothecaries, a situation which prolonged the conflicts between the faculty and the apothecaries. The financial and social distress prevalent in the 19(th) century also affected the apothecary business and led to a crisis of the profession. Furthermore, the apothecariesâ missing influence over the sanitary authorities delayed the release of a badly needed new apothecary bill until 1906. The introduction of a specific pharmaceutical curriculum at the university in 1853 was a great step forward to improve the pharmaceutical education. Nevertheless, the secondary school exam was not compulsory for the studies until 1920 and, therefore, the graduates were not on a par with other university graduates before that date. Women, except nuns, were not allowed to work as pharmacists until 1900. PMID:21179353

  12. Florence Nightingale: a 19th-century mystic.

    PubMed

    Dossey, Barbara M

    2010-03-01

    Florence Nightingale (1820-1910) received a clear and profoundly moving Call to serve God at the age of 16. Through a lifetime of hard work and discipline, she became a practicing mystic in the Western tradition, thereby becoming an instrument of God's love, which was the primarily source of her great energy and the fabled "Nightingale power." To understand the life and work of this legendary healer, who forever changed human consciousness, the role of women, and nursing and public health systems in the middle of the 19th century, it is necessary to understand her motivation and inspiration. This article will discuss her life and work in the context of her mystical practice and to show the parallels between her life and the lives of three recognized women mystics. In her epic Crimean war mission (1854-1856) of leading and directing women nurses in the army hospital at Scutari, Turkey, Florence Nightingale burst into world consciousness as a spiritual beacon of hope and compassion for all who suffered. Her historic breakthrough achievement--pioneering the modern administrative role of nurse superintendent with measurable outcomes supported by irrefutable data--in the face of incredible adversity was merely the cornerstone of her life work.

  13. [Cholera in Europe and Denmark in the 19th century].

    PubMed

    Bonderup, G

    1996-01-01

    There are several reasons for dealing with cholera in the 19th century: it acted as a spotlight throwing into sharp relief the darkest corners of society that are seldom mentioned in the sources. We learn about everyday life in large parts of the population, especially the poor. The fight against the disease also reveals how a society worked socially and politically. When cholera arrived in Europe -- the first time was in the 1830's and several times after that--the population reacted very violently, often by lynching doctors, while the authorities more or less let matters take their course. That is why international researchers have come to see cholera as a catalyst for the constantly latent social unrest following in the train of wars and revolutions. During my research on cholera in Denmark it became clear to me that matters were different here. There were no riots, nor any signs of social unrest--neither before nor after the outbreak of cholera. On the contrary, the authorities and the population joined forces against the epidemic. There was an atmosphere of mutual trust, and almost everybody turned out to be worthy of such trust. That points to a balanced society based on consensus, so cholera also functions as a detector of the fundamental structure of a society. PMID:11625139

  14. William Prout: early 19th century physician-chemist.

    PubMed

    Rosenfeld, Louis

    2003-04-01

    In the early 19th century, the discoveries of new substances in the healthy and diseased body spawned a search for chemical explanations for physiologic phenomena to guide medical diagnosis and control therapy. William Prout's work on the nature and treatment of diseases of the urinary organs established his reputation as one of Britain's most distinguished physiological chemists. Prout was very skeptical of chemical remedies because of possible side effects, but he suggested iodine treatment for goiter. He emphasized that a satisfactory diet should include carbohydrates, fats, protein, and water. In 1824, he showed that the acid of the gastric juice was hydrochloric acid. Prout applied chemical methods and reasoning to physiology and was criticized for his view that the body's vital functions could be explained by chemistry. His remedy for lack of progress in animal chemistry was for physiologists to become chemists. Prout stimulated much discussion on atomic theory by his hypothesis that the atomic weights of all chemical elements are whole-number multiples of the atomic weight of hydrogen and that the chemical elements were condensed from hydrogen atoms.

  15. Solar total irradiance in cycle 23

    NASA Astrophysics Data System (ADS)

    Krivova, N. A.; Solanki, S. K.; Schmutz, W.

    2011-05-01

    Context. The most recent minimum of solar activity was deeper and longer than the previous two minima as indicated by different proxies of solar activity. This is also true for the total solar irradiance (TSI) according to the PMOD composite. Aims: The apparently unusual behaviour of the TSI has been interpreted as evidence against solar surface magnetism as the main driver of the secular change in the TSI. We test claims that the evolution of the solar surface magnetic field does not reproduce the observed TSI in cycle 23. Methods: We use sensitive, 60-min averaged MDI magnetograms and quasi-simultaneous continuum images as an input to our SATIRE-S model and calculate the TSI variation over cycle 23, sampled roughly every two weeks. The computed TSI is then compared with the PMOD composite of TSI measurements and with the data from two individual instruments, SORCE/TIM and UARS/ACRIM II, that monitored the TSI during the declining phase of cycle 23 and over the previous minimum in 1996, respectively. Results: Excellent agreement is found between the trends shown by the model and almost all sets of measurements. The only exception is the early, i.e. 1996 to 1998, PMOD data. Whereas the agreement between the model and the PMOD composite over the period 1999-2009 is almost perfect, the modelled TSI shows a steeper increase between 1996 and 1999 than implied by the PMOD composite. On the other hand, the steeper trend in the model agrees remarkably well with the ACRIM II data. A closer look at the VIRGO data, which are the basis of the PMOD composite after 1996, reveals that only one of the two VIRGO instruments, the PMO6V, shows the shallower trend present in the composite, whereas the DIARAD measurements indicate a steeper trend. Conclusions: Based on these results, we conclude that (1) the sensitivity changes of the PMO6V radiometers within VIRGO during the first two years have very likely not been correctly evaluated; and that (2) the TSI variations over cycle 23

  16. CHARACTERISTICS OF SOLAR MERIDIONAL FLOWS DURING SOLAR CYCLE 23

    SciTech Connect

    Basu, Sarbani; Antia, H. M. E-mail: antia@tifr.res.i

    2010-07-01

    We have analyzed available full-disk data from the Michelson Doppler Imager on board SOHO using the 'ring diagram' technique to determine the behavior of solar meridional flows over solar cycle 23 in the outer 2% of the solar radius. We find that the dominant component of meridional flows during solar maximum was much lower than that during the minima at the beginning of cycles 23 and 24. There were differences in the flow velocities even between the two minima. The meridional flows show a migrating pattern with higher-velocity flows migrating toward the equator as activity increases. Additionally, we find that the migrating pattern of the meridional flow matches those of sunspot butterfly diagram and the zonal flows in the shallow layers. A high-latitude band in meridional flow appears around 2004, well before the current activity minimum. A Legendre polynomial decomposition of the meridional flows shows that the latitudinal pattern of the flow was also different during the maximum as compared to that during the two minima. The different components of the flow have different time dependences, and the dependence is different at different depths.

  17. A solar cycle lengthwise series of solar diameter measurements

    NASA Astrophysics Data System (ADS)

    Penna, J. L.; Andrei, A. H.; Boscardin, S. C.; Neto, E. Reis; d'Ávila, V. A.

    2010-02-01

    The measurements of the solar photospheric diameter rank among the most difficult astronomic observations. Reasons for this are the fuzzy definition of the limb, the SNR excess, and the adverse daytime seeing condition. As a consequence there are very few lengthy and consistent time series of such measurements. Using modern techniques, just the series from the IAG/USP and from Calern/OCA span more than one solar cycle. The Rio de Janeiro Group observations started in 1997, and therefore in 2008 one complete solar cycle time span can be analyzed. The series shares common principles of observation and analysis with the ones afore mentioned, and it is complementary on time to them. The distinctive features are the larger number of individual points and the improved precision. The series contains about 25,000 single observations, evenly distributed on a day-by-day basis. The typical error of a single observation is half an arc-second, enabling us to investigate variations at the expected level of tens of arc-second on a weekly basis. These features prompted to develop a new methodology for the investigation of the heliophysical scenarios leading to the observed variations, both on time and on heliolatitude. The algorithms rely on running averages and time shifts to derive the correlation and statistical incertitude for the comparison of the long term and major episodes variations of the solar diameter against activity markers. The results bring support to the correlation between the diameter variation and the solar activity, but evidentiating two different regimens for the long term trend and the major solar events.

  18. On the seat of the solar cycle

    NASA Technical Reports Server (NTRS)

    Gough, D.

    1981-01-01

    A discussion of some of the issues raised in connection with the seat of the solar cycle are presented. Is the cycle controlled by a strictly periodic oscillator that operates in the core, or is it a turbulent dynamo confined to the convection zone and possibly a thin boundary layer beneath it? Sunspot statistics are discussed, with a view to ascertaining the length of the memory of the cycle, without drawing a definitive conclusion. Also discussed are some of the processes that might bring about variations delta L and delta R in the luminosity and the radius of the photosphere. It appears that the ratio W = delta lnR/delta lnL increases with the depth of the disturbance that produces the variations, so that imminent observations might determine whether or not the principal dynamical processes are confined to only the outer layers of the Sun.

  19. Absinthism: a fictitious 19th century syndrome with present impact

    PubMed Central

    Padosch, Stephan A; Lachenmeier, Dirk W; Kröner, Lars U

    2006-01-01

    Absinthe, a bitter spirit containing wormwood (Artemisia absinthium L.), was banned at the beginning of the 20th century as consequence of its supposed unique adverse effects. After nearly century-long prohibition, absinthe has seen a resurgence after recent de-restriction in many European countries. This review provides information on the history of absinthe and one of its constituent, thujone. Medical and toxicological aspects experienced and discovered before the prohibition of absinthe are discussed in detail, along with their impact on the current situation. The only consistent conclusion that can be drawn from those 19th century studies about absinthism is that wormwood oil but not absinthe is a potent agent to cause seizures. Neither can it be concluded that the beverage itself was epileptogenic nor that the so-called absinthism can exactly be distinguished as a distinct syndrome from chronic alcoholism. The theory of a previous gross overestimation of the thujone content of absinthe may have been verified by a number of independent studies. Based on the current available evidence, thujone concentrations of both pre-ban and modern absinthes may not have been able to cause detrimental health effects other than those encountered in common alcoholism. Today, a questionable tendency of absinthe manufacturers can be ascertained that use the ancient theories of absinthism as a targeted marketing strategy to bring absinthe into the spheres of a legal drug-of-abuse. Misleading advertisements of aphrodisiac or psychotropic effects of absinthe try to re-establish absinthe's former reputation. In distinction from commercially manufactured absinthes with limited thujone content, a health risk to consumers is the uncontrolled trade of potentially unsafe herbal products such as absinthe essences that are readily available over the internet. PMID:16722551

  20. [Developments in neurophysiology in the 19th century].

    PubMed

    Hess, C W

    1994-04-19

    The rise of neurophysiology in the 19th century was kindled by Luigi Aloysius Galvani's revolutionary claim for animal electricity at the end of the preceding century. He was first challenged by Allessandro Giuseppe Antonio Anastasio Volta who showed that the muscle twitch in Galvani's experiment was the result of electric stimulation rather than of an enabled biological current. The controversy between Galvani and Volta became a predominant and stimulating issue among the scientists of the early century and found its ultimate elucidation only 40 years later by the pioneering work of Carlo Matteucci of Pisa and Emil Heinrich Du Bois-Reymond of Berlin, who both deserve the reknown as founders of modern neurophysiology. As the first influential promoter and mastermind of the experimental physiology, François Magendie of Paris primarily investigated the nervous system and inaugurated the lesion experiments to clarify specific functions of neural structures. Johannes Müller founded the German school of physiology with its eminent neurophysiological offspring: Du Bois-Reymond, Hermann Ludwig Ferdinand von Helmholtz, and Eduard Friedrich Wilhelm Pflüger. It was Helmholtz's merit to have for the first time precisely assessed the motor conduction velocity by measuring the time interval between two different stimulation sites of the sciatic nerve of the frog. In their brilliant work published in 1870 Gustav Theodor Fritsch and Eduard Hitzig demonstrated that appropriately located focal electrical stimulation of the exposed cortex of dogs induces movement of the contralateral limbs and unequivocally disproved the then prevailing dogma of holistic capacity of the hemispheres, which denied localised functions within the cortex.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. [Developments in neurophysiology in the 19th century].

    PubMed

    Hess, C W

    1994-04-19

    The rise of neurophysiology in the 19th century was kindled by Luigi Aloysius Galvani's revolutionary claim for animal electricity at the end of the preceding century. He was first challenged by Allessandro Giuseppe Antonio Anastasio Volta who showed that the muscle twitch in Galvani's experiment was the result of electric stimulation rather than of an enabled biological current. The controversy between Galvani and Volta became a predominant and stimulating issue among the scientists of the early century and found its ultimate elucidation only 40 years later by the pioneering work of Carlo Matteucci of Pisa and Emil Heinrich Du Bois-Reymond of Berlin, who both deserve the reknown as founders of modern neurophysiology. As the first influential promoter and mastermind of the experimental physiology, François Magendie of Paris primarily investigated the nervous system and inaugurated the lesion experiments to clarify specific functions of neural structures. Johannes Müller founded the German school of physiology with its eminent neurophysiological offspring: Du Bois-Reymond, Hermann Ludwig Ferdinand von Helmholtz, and Eduard Friedrich Wilhelm Pflüger. It was Helmholtz's merit to have for the first time precisely assessed the motor conduction velocity by measuring the time interval between two different stimulation sites of the sciatic nerve of the frog. In their brilliant work published in 1870 Gustav Theodor Fritsch and Eduard Hitzig demonstrated that appropriately located focal electrical stimulation of the exposed cortex of dogs induces movement of the contralateral limbs and unequivocally disproved the then prevailing dogma of holistic capacity of the hemispheres, which denied localised functions within the cortex.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8191189

  2. Solar origins of solar wind properties during the cycle 23 solar minimum and rising phase of cycle 24

    PubMed Central

    Luhmann, Janet G.; Petrie, Gordon; Riley, Pete

    2012-01-01

    The solar wind was originally envisioned using a simple dipolar corona/polar coronal hole sources picture, but modern observations and models, together with the recent unusual solar cycle minimum, have demonstrated the limitations of this picture. The solar surface fields in both polar and low-to-mid-latitude active region zones routinely produce coronal magnetic fields and related solar wind sources much more complex than a dipole. This makes low-to-mid latitude coronal holes and their associated streamer boundaries major contributors to what is observed in the ecliptic and affects the Earth. In this paper we use magnetogram-based coronal field models to describe the conditions that prevailed in the corona from the decline of cycle 23 into the rising phase of cycle 24. The results emphasize the need for adopting new views of what is ‘typical’ solar wind, even when the Sun is relatively inactive. PMID:25685422

  3. Solar origins of solar wind properties during the cycle 23 solar minimum and rising phase of cycle 24.

    PubMed

    Luhmann, Janet G; Petrie, Gordon; Riley, Pete

    2013-05-01

    The solar wind was originally envisioned using a simple dipolar corona/polar coronal hole sources picture, but modern observations and models, together with the recent unusual solar cycle minimum, have demonstrated the limitations of this picture. The solar surface fields in both polar and low-to-mid-latitude active region zones routinely produce coronal magnetic fields and related solar wind sources much more complex than a dipole. This makes low-to-mid latitude coronal holes and their associated streamer boundaries major contributors to what is observed in the ecliptic and affects the Earth. In this paper we use magnetogram-based coronal field models to describe the conditions that prevailed in the corona from the decline of cycle 23 into the rising phase of cycle 24. The results emphasize the need for adopting new views of what is 'typical' solar wind, even when the Sun is relatively inactive.

  4. Brayton cycle solarized advanced gas turbine

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Described is the development of a Brayton Engine/Generator Set for solar thermal to electrical power conversion, authorized under DOE/NASA Contract DEN3-181. The objective was to design, fabricate, assemble, and test a small, hybrid, 20-kW Brayton-engine-powered generator set. The latter, called a power conversion assembly (PCA), is designed to operate with solar energy obtained from a parobolic dish concentrator, 11 meters in diameter, or with fossil energy supplied by burning fuels in a combustor, or by a combination of both (hybrid model). The CPA consists of the Brayton cycle engine, a solar collector, a belt-driven 20-kW generator, and the necessary control systems for automatic operation in solar-only, fuel-only, and hybrid modes to supply electrical power to a utility grid. The original configuration of the generator set used the GTEC Model GTP36-51 gas turbine engine for the PCA prime mover. However, subsequent development of the GTEC Model AGT101 led to its selection as the powersource for the PCA. Performance characteristics of the latter, thermally coupled to a solar collector for operation in the solar mode, are presented. The PCA was successfully demonstrated in the fuel-only mode at the GTEC Phoenix, Arizona, facilities prior to its shipment to Sandia National Laboratory in Albuquerque, New Mexico, for installation and testing on a test bed concentractor (parabolic dish). Considerations relative to Brayton-engine development using the all-ceramic AGT101 when it becomes available, which would satisfy the DOE heat engine efficiency goal of 35 to 41 percent, are also discussed in the report.

  5. Contributions to the 19th International Cosmic Ray Conference

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Various aspects of cosmic radiation, its measurements and their patterns are presented. Measurement techniques and variations in solar cosmic ray patterns and calculations of elemental abundances are reviewed.

  6. Solar neutrinos, solar flares, solar activity cycle and the proton decay

    NASA Technical Reports Server (NTRS)

    Raychaudhuri, P.

    1985-01-01

    It is shown that there may be a correlation between the galactic cosmic rays and the solar neutrino data, but it appears that the neutrino flux which may be generated during the large solar cosmic ray events cannot in any way effect the solar neutrino data in Davis experiment. Only initial stage of mixing between the solar core and solar outer layers after the sunspot maximum in the solar activity cycle can explain the higher (run number 27 and 71) of solar neutrino data in Davis experiment. But solar flare induced atmospheric neutrino flux may have effect in the nucleon decay detector on the underground. The neutrino flux from solar cosmic rays may be a useful guide to understand the background of nucleon decay, magnetic monopole search, and the detection of neutrino flux in sea water experiment.

  7. An Improved Solar Cycle Statistical Model for the Projection of Near Future Sunspot Cycles

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Wilson, John W.; Cucinotta, Francis A.

    2004-01-01

    Since the current solar cycle 23 has progressed near the end of the cycle and accurate solar minimum and maximum occurrences have been defined, a statistical model based on the odd-even behavior of historical sunspot cycles was reexamined. Separate calculations of activity levels were made for the rising and declining phases in solar cycle 23, which resulted in improved projection of sunspots in the remainder of cycle 23. Because a fundamental understanding of the transition from cycle to cycle has not been developed, at this time it is assumed for projection purposes that solar cycle 24 will continue at the same activity level in the declining phase of cycle 23. Projection errors in solar cycle 24 can be corrected as the cycle progresses and observations become available because this model is shown to be self-correcting.

  8. Solar Cycle Changes of Coronal Streamer Properties

    NASA Astrophysics Data System (ADS)

    Strachan, L.; Baham, M.; Miralles, M.; Panasyuk, A.

    2003-12-01

    We have measured UV spectroscopic parameters, as a function of height for more than 30 coronal streamers in order to identify similarities between streamers at different phases of the solar cycle. For the period from 1996-2002, we provide line intensities, line widths, and line ratios for the O VI 1032/1037 doublet and intensities and line widths for the H I Ly-alpha line for these streamers. From such measurements we can derive plasma parameters (densities, temperatures, and outflow velocities) for O5+ and protons as a function of heliocentric height (1.5 > r/Ro > 5) in the streamers. This information is useful for setting empirical constraints on coronal heating and solar wind acceleration in streamers. This work is supported by NASA Grant NAG5-12781 to the Smithsonian Astrophysical Observatory and NASA subcontract OGSP21010200061SAO awarded to SAO through a grant to Southern Universty at Baton Rouge.

  9. Reading for Moral Progress: 19th Century Institutions Promoting Social Change. Occasional Papers No. 207.

    ERIC Educational Resources Information Center

    Davis, Donald G., Jr.; And Others

    The three papers in this document examine the motives behind the collecting and loaning of publications in the 19th century. They describe the effects of three discrete movements designed to assist religious, military, and academic endeavors. The first paper, "Bread Upon the Waters: The Printed Word in Sunday Schools in 19th Century England and…

  10. Ottoman Greek Education System and Greek Girls' Schools in Istanbul (19th and 20th Centuries)

    ERIC Educational Resources Information Center

    Daglar Macar, Oya

    2010-01-01

    Modernization efforts in education, which were initiated in the 19th century, can be seen as forerunners of the modernization attempts in the Republic period. In this article, Greek education system in the Ottoman Empire will be discussed and the effects and importance of the changes observed in Greek girls' education in 19th and 20th centuries on…

  11. The mid 19th and early 20th Century Pull of a Nearby Eclipse Shadow Path

    NASA Astrophysics Data System (ADS)

    Bonifácio, Vitor

    2012-09-01

    The unique observing conditions allowed by total solar eclipses made them a highly desirable target of 19th and early 20th century astronomical expeditions, particularly after 1842. Due to the narrowness of the lunar shadow at the Earth's surface this usually implied traveling to faraway locations with all the subsequent inconveniences, in particular, high costs and complex logistics. A situation that improved as travel became faster, cheaper and more reliable. The possibility to observe an eclipse in one's own country implied no customs, no language barriers, usually shorter travelling distances and the likely support of local and central authorities. The eclipse proximity also provided a strong argument to pressure the government to support the eclipse observation. Sometimes the scientific elite would use such high profile events to rhetorically promote broader goals. In this paper we will analyse the motivation, goals, negotiating strategies and outcomes of the Portuguese eclipse expeditions made between 1860 and 1914. We will focus, in particular, on the observation of the solar eclipses of 22 December 1870 and 17 April 1912. The former allowed the start-up of astrophysical studies in the country while the movie obtained at the latter led Francisco da Costa Lobo to unexpectedly propose a polar flattening of the Moon.

  12. Deep space telecommunications and the solar cycle: A reappraisal

    NASA Technical Reports Server (NTRS)

    Berman, A. L.

    1978-01-01

    Observations of density enhancement in the near corona at solar cycle (sunspot) maximum have rather uncritically been interpreted to apply equally well to the extended corona, thus generating concern about the quality of outer planet navigational data at solar cycle maximum. Spacecraft have been deployed almost continuously during the recently completed solar cycle 20, providing two powerful new coronal investigatory data sources: (1) in-situ spacecraft plasma measurements at approximately 1 AU, and (2) plasma effects on monochromatic spacecraft signals at all signal closest approach points. A comprehensive review of these (solar cycle 20) data lead to the somewhat surprising conclusions that for the region of interest of navigational data, the highest levels of charged particle corruption of navigational data can be expected to occur at solar cycle minimum, rather than solar cycle maximum, as previously believed.

  13. One Possible Reason for Double-Peaked Maxima in Solar Cycles: Is a Second Maximum of Solar Cycle 24 Expected?

    NASA Astrophysics Data System (ADS)

    Kilcik, A.; Ozguc, A.

    2014-04-01

    We investigate solar activity by focusing on double maxima in solar cycles and try to estimate the shape of the current solar cycle (Cycle 24) during its maximum. We analyzed data for Solar Cycle 24 by using Learmonth Solar Observatory sunspot-group data collected since 2008. All sunspot groups (SGs) recorded during this time interval were separated into two groups: The first group includes small SGs [A, B, C, and H classes according to the Zurich classification], the second group consists of large SGs [D, E, and F]. We then calculated how many small and large sunspot groups occurred, their sunspot numbers [SSN], and the Zurich numbers [ Rz] from their daily mean numbers as observed on the solar disk during a given month. We found that the temporal variations for these three different separations behave similarly. We also analyzed the general shape of solar cycles from Cycle 1 to 23 by using monthly International Sunspot Number [ISSN] data and found that the durations of maxima were about 2.9 years. Finally, we used the ascending time and SSN relationship and found that the maximum of Solar Cycle 24 is expected to occur later than 2011. Thus, we conclude that i) one possible reason for a double maximum in solar cycles is the different behavior of large and small sunspot groups, and ii) a double maximum is expected for Solar Cycle 24.

  14. Variations of the solar wind and solar cycle in the last 300 years

    NASA Technical Reports Server (NTRS)

    Feynman, J.; Silverman, S.

    1980-01-01

    The past history of the solar wind and solar cycle, inferred from records of geomagnetics and aurora, is examined. Records show that the solar wind apparently varied in a systematic manner throughout the period from 1770 to 1857 and that the period around 1810 resembled the 1901 minimum geomagnetic disturbance. Results show that the solar wind and hence the Sun changes on a time scale long compared to a solar cycle and short compared to the Maunder minimum. The inclusion of a study on the solar wind and solar cycle variations for the SCADM mission is discussed.

  15. International Conference on Challenges for Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Choudhary, Debi Prasad

    2007-05-01

    Physical Research Laboratory, Ahmedabad, India, 22-25 January 2007 What will be the nature of magnetic fields at various spatial and temporal scales on the Sun during the next activity cycle? This and other outstanding questions of solar physics were the focus of discussion at the International Conference on Challenges for Solar Cycle 24. Observational solar research is equipped with ever advanced instrumentation during each solar cycle. The use of modern instrumentation for solar observations will yield better results when planned with prior knowledge gained during previous activity cycles. With this motivation, the goal of the conference was to consider the most effective strategies for studying and understanding the solar energetic events of cycle 24.

  16. Variability of Clouds Over a Solar Cycle

    NASA Technical Reports Server (NTRS)

    Yung, Yuk L.

    2002-01-01

    One of the most controversial aspects of climate studies is the debate over the natural and anthropogenic causes of climate change. Historical data strongly suggest that the Little Ice Age (from 1550 to 1850 AD when the mean temperature was colder by about 1 C) was most likely caused by variability of the sun and not greenhouse molecules (e.g., CO2). However, the known variability in solar irradiance and modulation of cosmic rays provides too little energy, by many orders of magnitude, to lead to climate changes in the troposphere. The conjecture is that there is a 'trigger mechanism'. This idea may now be subjected to a quantitative test using recent global datasets. Using the best available modern cloud data from International Satellite Cloud Climatology Project (ISCCP), Svensmark and Friis-Christensen found a correlation of a large variation (3-4%) in global cloud cover with the solar cycle. The work has been extended by Svensmark and Marsh and Svensmark. The implied forcing on climate is an order of magnitude greater than any previous claims. Are clouds the long sought trigger mechanism? This discovery is potentially so important that it should be corroborated by an independent database, and, furthermore, it must be shown that alternative explanations (i.e., El Nino) can be ruled out. We used the ISCCP data in conjunction with the Total Ozone Mapping Spectrometer (TOMS) data to carry out in in depth study of the cloud trigger mechanism.

  17. SOLAR SOURCES OF {sup 3}He-RICH SOLAR ENERGETIC PARTICLE EVENTS IN SOLAR CYCLE 24

    SciTech Connect

    Nitta, Nariaki V.; Wang, Linghua; Cohen, Christina M. S.; Wiedenbeck, Mark E. E-mail: glenn.mason@jhuapl.edu E-mail: cohen@srl.caltech.edu

    2015-06-20

    Using high-cadence EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, we investigate the solar sources of 26 {sup 3}He-rich solar energetic particle events at ≲1 MeV nucleon{sup −1} that were well-observed by the Advanced Composition Explorer during solar cycle 24. Identification of the solar sources is based on the association of {sup 3}He-rich events with type III radio bursts and electron events as observed by Wind. The source locations are further verified in EUV images from the Solar and Terrestrial Relations Observatory, which provides information on solar activities in the regions not visible from the Earth. Based on AIA observations, {sup 3}He-rich events are not only associated with coronal jets as emphasized in solar cycle 23 studies, but also with more spatially extended eruptions. The properties of the {sup 3}He-rich events do not appear to be strongly correlated with those of the source regions. As in the previous studies, the magnetic connection between the source region and the observer is not always reproduced adequately by the simple potential field source surface model combined with the Parker spiral. Instead, we find a broad longitudinal distribution of the source regions extending well beyond the west limb, with the longitude deviating significantly from that expected from the observed solar wind speed.

  18. Solar Sources of 3He-rich Solar Energetic Particle Events in Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Nitta, Nariaki V.; Mason, Glenn M.; Wang, Linghua; Cohen, Christina M. S.; Wiedenbeck, Mark E.

    2015-06-01

    Using high-cadence EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory, we investigate the solar sources of 26 3He-rich solar energetic particle events at ≲1 MeV nucleon-1 that were well-observed by the Advanced Composition Explorer during solar cycle 24. Identification of the solar sources is based on the association of 3He-rich events with type III radio bursts and electron events as observed by Wind. The source locations are further verified in EUV images from the Solar and Terrestrial Relations Observatory, which provides information on solar activities in the regions not visible from the Earth. Based on AIA observations, 3He-rich events are not only associated with coronal jets as emphasized in solar cycle 23 studies, but also with more spatially extended eruptions. The properties of the 3He-rich events do not appear to be strongly correlated with those of the source regions. As in the previous studies, the magnetic connection between the source region and the observer is not always reproduced adequately by the simple potential field source surface model combined with the Parker spiral. Instead, we find a broad longitudinal distribution of the source regions extending well beyond the west limb, with the longitude deviating significantly from that expected from the observed solar wind speed.

  19. Solar UV Variations During the Decline of Cycle 23

    NASA Technical Reports Server (NTRS)

    DeLand, Matthew, T.; Cebula, Richard P.

    2011-01-01

    Characterization of temporal and spectral variations in solar ultraviolet irradiance over a solar cycle is essential for understanding the forcing of Earth's atmosphere and climate. Satellite measurements of solar UV variability for solar cycles 21, 22, and 23 show consistent solar cycle irradiance changes at key wavelengths (e.g. 205 nm, 250 nm) within instrumental uncertainties. All historical data sets also show the same relative spectral dependence for both short-term (rotational) and long-term (solar cycle) variations. Empirical solar irradiance models also produce long-term solar UV variations that agree well with observational data. Recent UV irradiance data from the Solar Radiation and Climate Experiment (SORCE) Spectral Irradiance Monitor (SIM) and Solar Stellar Irradiance Comparison Experiment (SOLSTICE) instruments covering the declining phase of Cycle 23 present a different picture oflong-term solar variations from previous results. Time series of SIM and SOLSTICE spectral irradiance data between 2003 and 2007 show solar variations that greatly exceed both previous measurements and predicted irradiance changes over this period, and the spectral dependence of the SIM and SOLSTICE variations during these years do not show features expected from solar physics theory. The use of SORCE irradiance variations in atmospheric models yields substantially different middle atmosphere ozone responses in both magnitude and vertical structure. However, short-term solar variability derived from SIM and SOLSTICE UV irradiance data is consistent with concurrent solar UV measurements from other instruments, as well as previous results, suggesting no change in solar physics. Our analysis of short-term solar variability is much less sensitive to residual instrument response changes than the observations of long-term variations. The SORCE long-term UV results can be explained by under-correction of instrument response changes during the first few years of measurements

  20. 4. LOOKING NORTHEAST TOWARDS LOCKS. 19TH CENTURY GRAVITY LOCKS ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. LOOKING NORTHEAST TOWARDS LOCKS. 19TH CENTURY GRAVITY LOCKS ON RIGHT. 20TH CENTURY ELECTRIC LIFT LOCKS ON LEFT. - New York State Barge Canal, Lockport Locks, Richmond Avenue, Lockport, Niagara County, NY

  1. Heat and Kinetic Theory in 19th-Century Physics Textbooks: The Case of Spain.

    ERIC Educational Resources Information Center

    Vaquero, Jose M.; Santos, Andres

    2001-01-01

    Presents an analysis of the contents of 19th century Spanish textbooks. These textbooks are centered on imponderable fluids, the concept of energy, the mechanical theory of heat, and the kinetic theory of gases. (SAH)

  2. 10. Photograph of engraving. W.E. Tucker, Printer, undated (19th century). ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Photograph of engraving. W.E. Tucker, Printer, undated (19th century). EAST FACADE AND ORIGINAL LANDSCAPING - Pennsylvania Hospital for Mental & Nervous Diseases, Forty-fourth & Market Streets, Philadelphia, Philadelphia County, PA

  3. INTERNAL-CYCLE VARIATION OF SOLAR DIFFERENTIAL ROTATION

    SciTech Connect

    Li, K. J.; Xie, J. L.; Shi, X. J.

    2013-06-01

    The latitudinal distributions of the yearly mean rotation rates measured by Suzuki in 1998 and 2012 and Pulkkinen and Tuominen in 1998 are utilized to investigate internal-cycle variation of solar differential rotation. The rotation rate at the solar equator seems to have decreased since cycle 10 onward. The coefficient B of solar differential rotation, which represents the latitudinal gradient of rotation, is found to be smaller in the several years after the minimum of a solar cycle than in the several years after the maximum time of the cycle, and it peaks several years after the maximum time of the solar cycle. The internal-cycle variation of the solar rotation rates looks similar in profile to that of the coefficient B. A new explanation is proposed to address such a solar-cycle-related variation of the solar rotation rates. Weak magnetic fields may more effectively reflect differentiation at low latitudes with high rotation rates than at high latitudes with low rotation rates, and strong magnetic fields may more effectively repress differentiation at relatively low latitudes than at high latitudes. The internal-cycle variation is inferred as the result of both the latitudinal migration of the surface torsional pattern and the repression of strong magnetic activity in differentiation.

  4. The solar cycle - A central-source wave theory

    NASA Technical Reports Server (NTRS)

    Bracewell, R. N.

    1989-01-01

    Studies stimulated by the interpretation of the Elatina formation in South Australia as a fossil record of solar activity have led to discoveries of previously unnoticed features of the sunspot cycle record and to a theory of origin of the sunspot cycle that postulates a solar core in torsional motion and a magnetomechanical wave that couples to the photosphere. The considerations supporting the solar interpretation of the Elatina formation are gathered together.

  5. Rings of madness: service areas of 19th century asylums in North America.

    PubMed

    Hunter, J M; Shannon, G W; Sambrook, S L

    1986-01-01

    The mid-19th century saw the emergence of a major medical innovation, namely, the rise of the state lunatic asylum. Beginning in the northeast, the phenomenon spread rapidly westwards. By 1875 no fewer than 71 mental hospitals were opened in 32 existing states. Although premised upon belief in the efficacy of 'moral and humane' treatment, the asylums soon became custodial rather than therapeutic institutions. Average size continually increased; some accommodated well over 2000 patients. The provision of more asylums, and broadened definitions of insanity, generated increasing patient numbers which, in turn, caused public consternation and fear of increasing 'madness' in the population. Geographic analysis of admissions in 18 U.S. states and two Canadian provinces reveals the universality of distance decay around the asylums, and demonstrates that hospital service-area cones were predominantly local in effect. Thus the 'state' asylum was in reality a local institution. The deinstitutionalization movement of recent decades is apparently bringing to a closure a 100-year cycle of incarceration-decarceration of the mentally ill. Nevertheless, whether patients are geographically concentrated or dispersed, the influence of distance decay remains a relevant consideration.

  6. Predicting Solar Cycle 24 Using a Geomagnetic Precursor Pair

    NASA Technical Reports Server (NTRS)

    Pesnell, W. Dean

    2014-01-01

    We describe using Ap and F(10.7) as a geomagnetic-precursor pair to predict the amplitude of Solar Cycle 24. The precursor is created by using F(10.7) to remove the direct solar-activity component of Ap. Four peaks are seen in the precursor function during the decline of Solar Cycle 23. A recurrence index that is generated by a local correlation of Ap is then used to determine which peak is the correct precursor. The earliest peak is the most prominent but coincides with high levels of non-recurrent solar activity associated with the intense solar activity of October and November 2003. The second and third peaks coincide with some recurrent activity on the Sun and show that a weak cycle precursor closely following a period of strong solar activity may be difficult to resolve. A fourth peak, which appears in early 2008 and has recurrent activity similar to precursors of earlier solar cycles, appears to be the "true" precursor peak for Solar Cycle 24 and predicts the smallest amplitude for Solar Cycle 24. To determine the timing of peak activity it is noted that the average time between the precursor peak and the following maximum is approximately equal to 6.4 years. Hence, Solar Cycle 24 would peak during 2014. Several effects contribute to the smaller prediction when compared with other geomagnetic-precursor predictions. During Solar Cycle 23 the correlation between sunspot number and F(10.7) shows that F(10.7) is higher than the equivalent sunspot number over most of the cycle, implying that the sunspot number underestimates the solar-activity component described by F(10.7). During 2003 the correlation between aa and Ap shows that aa is 10 % higher than the value predicted from Ap, leading to an overestimate of the aa precursor for that year. However, the most important difference is the lack of recurrent activity in the first three peaks and the presence of significant recurrent activity in the fourth. While the prediction is for an amplitude of Solar Cycle 24 of

  7. Hybrid solar central receiver for combined cycle power plant

    DOEpatents

    Bharathan, D.; Bohn, M.S.; Williams, T.A.

    1995-05-23

    A hybrid combined cycle power plant is described including a solar central receiver for receiving solar radiation and converting it to thermal energy. The power plant includes a molten salt heat transfer medium for transferring the thermal energy to an air heater. The air heater uses the thermal energy to preheat the air from the compressor of the gas cycle. The exhaust gases from the gas cycle are directed to a steam turbine for additional energy production. 1 figure.

  8. Hybrid solar central receiver for combined cycle power plant

    DOEpatents

    Bharathan, Desikan; Bohn, Mark S.; Williams, Thomas A.

    1995-01-01

    A hybrid combined cycle power plant including a solar central receiver for receiving solar radiation and converting it to thermal energy. The power plant includes a molten salt heat transfer medium for transferring the thermal energy to an air heater. The air heater uses the thermal energy to preheat the air from the compressor of the gas cycle. The exhaust gases from the gas cycle are directed to a steam turbine for additional energy production.

  9. Solar Ultraviolet Irradiance Variability During the Decline of Cycle 23

    NASA Astrophysics Data System (ADS)

    Snow, M. A.; McClintock, W. E.; Woods, T. N.; Harder, J. W.; Richard, E. C.

    2010-12-01

    Observations from the SOLar-STellar Irradiance Comparision Experiment (SOLSTICE) on the SOlar Radiation and Climate Experiment (SORCE) began in 2003 and continue through the present. This time period includes the decline of solar cycle 23 through solar minimum. SOLSTICE measures solar irradiance from 115 nm to 300 nm with a spectral resolution of 0.1 nm. The variability seen by SORCE SOLSTICE is greater than the variability recorded by the instruments on the Upper Atmosphere Research Satellite(UARS). This poster will describe the magnitude and uncertainty of solar irradiance variability in the ultraviolet part of the spectrum during the SORCE mission with comparisons to irradiance models based on UARS measurements.

  10. Search for a relationship between solar cycle amplitude and length

    NASA Astrophysics Data System (ADS)

    Solanki, S. K.; Krivova, N. A.; Schüssler, M.; Fligge, M.

    2002-12-01

    The cross-correlation between time series of solar cycle length and amplitude suggests that the length precedes the amplitude. The relationship between the two is found to be more complex than a simple lag or phase shift, however. A simple empirical model is constructed which allows the amplitude of a given cycle to be predicted with relatively high accuracy from the lengths of earlier cycles. This result not only adds to the means at our disposal for predicting the amplitudes of future cycles, but also implies that the solar dynamo carries a memory of the length of one cycle over into the next. It may also have a bearing on why solar cycle length correlates better with the Earth's temperature record than cycle amplitude (Friis-Christensen & Lassen \\cite{Friis-Christensen:Lassen:1991}). Thoughts on possible physical causes are presented.

  11. [JAN JĘDRZEJEWICZ AND EUROPEAN ASTRONOMY OF THE 2ND HALF OF THE 19TH CENTURY].

    PubMed

    Siuda-Bochenek, Magda

    2015-01-01

    Jan Jędrzejewicz was an amateur astronomer who in the 2nd half of the 19th century created an observation centre, which considering the level of research was comparable to the European ones. Jędrzejewicz settled down in Plonsk in 1862 and worked as a doctor ever since but his greatest passion was astronomy, to which he dedicated all his free time. In 1875 Jędrzejewicz finished the construction of his observatory. He equipped it with basic astronomical and meteorological instruments, then began his observations and with time he became quite skilled in it. Jędrzejewicz focused mainly on binary stars but he also pointed his telescopes at the planets of the solar system, the comets, the Sun, as well as all the phenomena appearing in the sky at that time. Thanks to the variety of the objects observed and the number of observations he stood out from other observers in Poland and took a very good position in the mainstream of the 19th-century astronomy in Europe. Micrometer observations of binary stars made in Płońsk gained recognition in the West and were included in the catalogues of binary stars. Interest in Jędrzejewicz and his observatory was confirmed by numerous references in the English "Nature" magazine.

  12. [JAN JĘDRZEJEWICZ AND EUROPEAN ASTRONOMY OF THE 2ND HALF OF THE 19TH CENTURY].

    PubMed

    Siuda-Bochenek, Magda

    2015-01-01

    Jan Jędrzejewicz was an amateur astronomer who in the 2nd half of the 19th century created an observation centre, which considering the level of research was comparable to the European ones. Jędrzejewicz settled down in Plonsk in 1862 and worked as a doctor ever since but his greatest passion was astronomy, to which he dedicated all his free time. In 1875 Jędrzejewicz finished the construction of his observatory. He equipped it with basic astronomical and meteorological instruments, then began his observations and with time he became quite skilled in it. Jędrzejewicz focused mainly on binary stars but he also pointed his telescopes at the planets of the solar system, the comets, the Sun, as well as all the phenomena appearing in the sky at that time. Thanks to the variety of the objects observed and the number of observations he stood out from other observers in Poland and took a very good position in the mainstream of the 19th-century astronomy in Europe. Micrometer observations of binary stars made in Płońsk gained recognition in the West and were included in the catalogues of binary stars. Interest in Jędrzejewicz and his observatory was confirmed by numerous references in the English "Nature" magazine. PMID:26455002

  13. DMSP Auroral Charging at Solar Cycle 24 Maximum

    NASA Technical Reports Server (NTRS)

    Chandler, Michael; Parker, Linda Neergaard; Minow, Joseph I.

    2013-01-01

    It has been well established that polar orbiting satellites can experience mild to severe auroral charging levels (on the order of a few hundred volts to few kilovolts negative frame potentials) during solar minimum conditions (Frooninckx and Sojka, 1992; Anderson and Koons, 1996; Anderson, 2012). These same studies have shown a strong reduction in charging during the rising and declining phases of the past few solar cycles with a nearly complete suppression of auroral charging at solar maximum. Recently, we have observed examples of high level charging during the recent approach to Solar Cycle 24 solar maximum conditions not unlike those reported by Frooninckx and Sojka (1992). These observations demonstrate that spacecraft operations during solar maximum cannot be considered safe from auroral charging when solar activity is low. We present a survey of auroral charging events experienced by the Defense Meteorological Satellite Program (DMSP) F16 satellite during Solar Cycle 24 maximum conditions. We summarize the auroral energetic particle environment and the conditions necessary for charging to occur in this environment, we describe how the lower than normal solar activity levels for Solar Cycle 24 maximum conditions are conducive to charging in polar orbits, and we show examples of the more extreme charging events, sometimes exceeding 1 kV, during this time period.

  14. DMSP Auroral Charging at Solar Cycle 24 Maximum

    NASA Technical Reports Server (NTRS)

    Chandler, M.; Parker, L. Neergaard; Minow, J. I.

    2013-01-01

    It has been well established that polar orbiting satellites can experience mild to severe auroral charging levels (on the order of a few hundred volts to few kilovolts negative frame potentials) during solar minimum conditions. These same studies have shown a strong reduction in charging during the rising and declining phases of the past few solar cycles with a nearly complete suppression of auroral charging at solar maximum. Recently, we have observed examples of high level charging during the recent approach to Solar Cycle 24 solar maximum conditions not unlike those reported by Frooninckx and Sojka. These observations demonstrate that spacecraft operations during solar maximum cannot be considered safe from auroral charging when solar activity is low. We present a survey of auroral charging events experienced by the Defense Meteorological Satellite Program (DMSP) F16 satellite during Solar Cycle 24 maximum conditions. We summarize the auroral energetic particle environment and the conditions necessary for charging to occur in this environment, we describe how the lower than normal solar activity levels for Solar Cycle 24 maximum conditions are conducive to charging in polar orbits, and we show examples of the more extreme charging events, sometimes exceeding 1 kV, during this time period.

  15. Solar cycle effects on Indian summer monsoon dynamics

    NASA Astrophysics Data System (ADS)

    Ratnam, M. Venkat; Santhi, Y. Durga; Kishore, P.; Rao, S. Vijaya Bhaskara

    2014-12-01

    Solar activity associated with sunspot number influences the atmospheric circulation on various time scales. As Indian summer monsoon (ISM) is the manifestation between warmer Asian continent and the cooler Indian Ocean, changes in the solar cycle are expected to influence the ISM characteristics. Among several elements of ISM, Tropical Easterly Jet (TEJ), Low Level Jet (LLJ), and rainfall are important features. As a part of CAWSES India Phase II theme 1 (solar influence on climate (0-100 km)) programme, we made an attempt to investigate the role of solar cycle variability on these ISM features using long-term data available from NECP/NCAR (1948-2010) and ERA-Interim (1979-2010) re-analysis products. To check the suitability of these data sets, ground based observations available over the Indian region are also considered. ISM characteristics are studied separately for the maximum and minimum as well as increasing and decreasing solar cycle conditions. Amplitudes corresponding to the solar cycle observed in TEJ, LLJ and rainfall are extracted using advanced statistical tool known as intrinsic mode function. Long-term trends in TEJ reveal decreasing trend at the rate of 0.13 m/s/yr (between 1948 and 2000) and no perceptible trend in LLJ. There exists inverse relation between TEJ strength and Central India rainfall. Large difference of 2 m/s (5 m/s) in the zonal winds of TEJ between solar maximum and minimum (increasing and decreasing trend) is noticed. There exists a difference of ~2 m/s in LLJ winds between solar maximum and minimum and increasing and decreasing trend of the solar cycle. However, no consistent relation between the ISM rainfall and solar cycle is noticed over Indian region unlike reported earlier but there exists a delayed effect around 13 years. We attribute the observed features as linear and non-linear relation between dynamics of ISM, rainfall and solar cycle, respectively.

  16. Response of Solar Oscillations to Magnetic Activity in Cycle 24

    NASA Astrophysics Data System (ADS)

    Jain, K.; Tripathy, S. C.; Hill, F.

    2015-12-01

    Acoustic mode parameters are generally used to study the variability of the solar interior in response to changing magnetic activity. While oscillation frequencies do vary in phase with the solar activity, the mode amplitudes are anti-correlated. Now, continuous measurements from ground and space allow us study the origin of such variability in detail. Here we use intermediate-dgree mode frequencies computed from a ground-based 6-site network ( GONG), covering almost two solar cycles from the minimum of cycle 23 to the declining phase of cycle 24, to investigate the effect of remarkably low solar activity on the solar oscillations in current cycle and the preceding minimum; is the response of acoustic oscillations to magnetic activity in cycle 24 similar to cycle 23 or there are differences between cycles 23 and 24? In this paper, we analyze results for both solar cycles, and try to understand the origin of similarities/differences between them. We will also compare our findings with the contemporaneous observations from space (SOHO/MDI and SDO/HMI).

  17. Variation of Solar, Interplanetary and Geomagnetic Parameters during Solar Cycles 21-24

    NASA Astrophysics Data System (ADS)

    Oh, Suyeon; Kim, Bogyeong

    2013-06-01

    The length of solar cycle 23 has been prolonged up to about 13 years. Many studies have speculated that the solar cycle 23/24 minimum will indicate the onset of a grand minimum of solar activity, such as the Maunder Minimum. We check the trends of solar (sunspot number, solar magnetic fields, total solar irradiance, solar radio flux, and frequency of solar X-ray flare), interplanetary (interplanetary magnetic field, solar wind and galactic cosmic ray intensity), and geomagnetic (Ap index) parameters (SIG parameters) during solar cycles 21-24. Most SIG parameters during the period of the solar cycle 23/24 minimum have remarkably low values. Since the 1970s, the space environment has been monitored by ground observatories and satellites. Such prevalently low values of SIG parameters have never been seen. We suggest that these unprecedented conditions of SIG parameters originate from the weakened solar magnetic fields. Meanwhile, the deep 23/24 solar cycle minimum might be the portent of a grand minimum in which the global mean temperature of the lower atmosphere is as low as in the period of Dalton or Maunder minimum.

  18. Forecasting the Peak of the Present Solar Activity Cycle

    NASA Astrophysics Data System (ADS)

    Hamid, Rabab; Marzouk, Beshir

    2016-07-01

    Solar forecasting of the level of sun Activity is very important subject for all space programs. Most predictions are based on the physical conditions prevailing at or before the solar cycle minimum preceding the maximum in question. Our aim is to predict the maximum peak of cycle 24 using precursor techniques in particular those using spotless event, geomagnetic aa min. index and solar flux F10.7. Also prediction of exact date of the maximum (Tr) is taken in consideration. A study of variation over previous spotless event for cycles 7-23 and that for even cycles (8-22) are carried out for the prediction. Linear correlation between RM and spotless event around the preceding minimum gives RM24t = 101.9with rise time Tr = 4.5 Y. For the even cycles RM24e = 108.3 with rise time Tr = 3.9 Y. Based on the average aa min. index for the year of sunspot minimum cycles (13 - 23), we estimate the expected amplitude for cycle 24 to be RMaa = 116.5 for both the total and even cycles. Application of the data of solar flux F10.7 which cover only cycles (19-23) was taken in consideration and gives predicted maximum amplitude R24 10.7 = 146, which are over estimation. Our result indicating a somewhat weaker cycle 24 as compared to cycles 21-23.

  19. Geomagnetic research in the 19th century: a case study of the German contribution

    NASA Astrophysics Data System (ADS)

    Schröder, W.; Wiederkehr, K.-H.

    2001-10-01

    Even before the discovery of electromagnetism by Oersted, and before the work of Ampère, who attributed all magnetism to the flux of electrical currents, A.v. Humboldt and Hansteen had turned to geomagnetism. Through the ``Göttinger Magnetischer Verein'', a worldwide cooperation under the leadership of Gauss came into existence. Even today, Gauss's theory of geomagnetism is one of the pillars of geomagnetic research. Thereafter, J.v. Lamont, in Munich, took over the leadership in Germany. In England, the Magnetic Crusade was started by the initiative of John Herschel and E. Sabine. At the beginning of the 1840s, James Clarke Ross advanced to the vicinity of the southern magnetic pole on the Antarctic Continent, which was then quite unknown. Ten years later, Sabine was able to demonstrate solar-terrestrial relations from the data of the colonial observatories. In the 1980s, Arthur Schuster, following Balfour Stewart's ideas, succeeded in interpreting the daily variations of the electrical process in the high atmosphere. Geomagnetic research work in Germany was given a fresh impetus by the programme of the First Polar Year 1882-1883. Georg Neumayer, director of the ``Deutsche Seewarte'' in Hamburg, was one of the initiators of the Polar Year. He forged a close cooperation with the newly founded ``Kaiserliches Marineobservatorium'' in Wilhelmshaven, and also managed to gain the collaboration of the ``Gauss-Observatorium für Erdmagnetismus'' in Göttingen under E. Schering. In the Polar Year, the first automatic recording magnetometers (Kew-Model) were used in the German observatory at Wilhelmshaven. Here, M. Eschenhagen, who later became director of the geomagnetic section in the new Meteorological Magnetic Observatory in Potsdam, deserves special credit. Early hypotheses of geomagnetism and pioneering palaeomagnetic experiments are briefly reviewed. The essential seismological investigations at the turn of the 19th to the 20th century are also briefly described as

  20. Solar thermal organic rankine cycle for micro-generation

    NASA Astrophysics Data System (ADS)

    Alkahli, N. A.; Abdullah, H.; Darus, A. N.; Jalaludin, A. F.

    2012-06-01

    The conceptual design of an Organic Rankine Cycle (ORC) driven by solar thermal energy is developed for the decentralized production of electricity of up to 50 kW. Conventional Rankine Cycle uses water as the working fluid whereas ORC uses organic compound as the working fluid and it is particularly suitable for low temperature applications. The ORC and the solar collector will be sized according to the solar flux distribution in the Republic of Yemen for the required power output of 50 kW. This will be a micro power generation system that consists of two cycles, the solar thermal cycle that harness solar energy and the power cycle, which is the ORC that generates electricity. As for the solar thermal cycle, heat transfer fluid (HTF) circulates the cycle while absorbing thermal energy from the sun through a parabolic trough collector and then storing it in a thermal storage to increase system efficiency and maintains system operation during low radiation. The heat is then transferred to the organic fluid in the ORC via a heat exchanger. The organic fluids to be used and analyzed in the ORC are hydrocarbons R600a and R290.

  1. Data Assimilation Approach for Forecast of Solar Activity Cycles

    NASA Astrophysics Data System (ADS)

    Kitiashvili, Irina N.

    2016-11-01

    Numerous attempts to predict future solar cycles are mostly based on empirical relations derived from observations of previous cycles, and they yield a wide range of predicted strengths and durations of the cycles. Results obtained with current dynamo models also deviate strongly from each other, thus raising questions about criteria to quantify the reliability of such predictions. The primary difficulties in modeling future solar activity are shortcomings of both the dynamo models and observations that do not allow us to determine the current and past states of the global solar magnetic structure and its dynamics. Data assimilation is a relatively new approach to develop physics-based predictions and estimate their uncertainties in situations where the physical properties of a system are not well-known. This paper presents an application of the ensemble Kalman filter method for modeling and prediction of solar cycles through use of a low-order nonlinear dynamo model that includes the essential physics and can describe general properties of the sunspot cycles. Despite the simplicity of this model, the data assimilation approach provides reasonable estimates for the strengths of future solar cycles. In particular, the prediction of Cycle 24 calculated and published in 2008 is so far holding up quite well. In this paper, I will present my first attempt to predict Cycle 25 using the data assimilation approach, and discuss the uncertainties of that prediction.

  2. The purple coloration of four late 19th century silk dresses: A spectroscopic investigation

    NASA Astrophysics Data System (ADS)

    Woodhead, Andrea L.; Cosgrove, Bronwyn; Church, Jeffrey S.

    2016-02-01

    Prior to the 19th century the use of purple dyes for textile coloration was expensive and usually limited to royalty. The discovery of several synthetic purple dyes during the 19th century made the production of purple textiles more affordable and thus more readily available. The identification of the source of the purple coloration is of historical interest. Small yarn samples from four late 19th century silk dresses were analyzed using a combination of thin layer chromatography and surface enhanced Raman spectroscopy, Fourier transform infrared spectroscopy and energy dispersive x-ray spectroscopy. This combination of techniques enabled the analysis of the complex extraction products. While three of the dresses were found to be dyed using methyl violet, the fourth dress was found to be constructed from a warp yarn dyed with methyl violet in the presence of a tannic acid mordant, and a weft yarn dyed with mauve and a tin mordant.

  3. The purple coloration of four late 19th century silk dresses: A spectroscopic investigation.

    PubMed

    Woodhead, Andrea L; Cosgrove, Bronwyn; Church, Jeffrey S

    2016-02-01

    Prior to the 19th century the use of purple dyes for textile coloration was expensive and usually limited to royalty. The discovery of several synthetic purple dyes during the 19th century made the production of purple textiles more affordable and thus more readily available. The identification of the source of the purple coloration is of historical interest. Small yarn samples from four late 19th century silk dresses were analyzed using a combination of thin layer chromatography and surface enhanced Raman spectroscopy, Fourier transform infrared spectroscopy and energy dispersive x-ray spectroscopy. This combination of techniques enabled the analysis of the complex extraction products. While three of the dresses were found to be dyed using methyl violet, the fourth dress was found to be constructed from a warp yarn dyed with methyl violet in the presence of a tannic acid mordant, and a weft yarn dyed with mauve and a tin mordant. PMID:26523685

  4. Solar Cycle Spectral Irradiance Variation and Stratospheric Ozone

    NASA Astrophysics Data System (ADS)

    Stolarski, R. S.; Swartz, W. H.; Jackman, C. H.; Fleming, E. L.

    2011-12-01

    Recent measurements from the SIM instrument on the SORCE satellite have been interpreted by Harder et al (Geophys. Res. Lett., 36, L07801, doi:10.1029/2008GL036797, 2009) as implying a different spectral irradiance variation over the solar cycle than that put forward by Lean (Geophys. Res. Lett., 27, 2425-2428, 2000). When we inserted this new wavelength dependent solar cycle variation into our 3D CCM we found a different solar cycle dependence of the ozone concentration as a function of altitude from that we derived using the traditional Lean wavelength dependence. Examination of these results led us to realize that the main issue is the solar cycle variation of radiation at wavelengths less than 240 nm versus the solar cycle variation of radiation at wavelengths between 240 nm and 300 nm. The impact of wavelengths less than 240 nm occurs through photodissociation of O2 leading to the production of ozone. The impact of wavelengths between 240 nm and 300 nm occurs through photodissociation of O3 leading to an increase in O atoms and enhanced ozone destruction. Thus one wavelength region gives an in-phase relationship of ozone with the solar cycle while the other wavelength region gives an out-of-phase relationship of ozone with the solar cycle. We have used the Goddard two-dimensional (2D) photochemistry transport model to examine this relationship in more detail. We calculate the altitude and latitude sensitivity of ozone to changes in the solar UV irradiance as a function of wavelength. These results can be used to construct the ozone response to arbitrary wavelength dependencies of solar UV variation.

  5. Cosmic Ray Helium Intensities over the Solar Cycle from ACE

    NASA Technical Reports Server (NTRS)

    DeNolfo, G. A.; Yanasak, N. E.; Binns, W. R.; Cohen, C. M. S.; Cummings, A. C.; Davis, A. J.; George, J. S.; Hink. P. L.; Israel, M. H.; Lave, K.; Leske, R. A.; Mewaldt, R. A.; Moskalenko, I. V.; Ogliore, R.; Stone, E. C.; Von Rosenvinge, T. T.; Wiedenback, M. E.

    2007-01-01

    Observations of cosmic-ray helium energy spectra provide important constraints on cosmic ray origin and propagation. However, helium intensities measured at Earth are affected by solar modulation, especially below several GeV/nucleon. Observations of helium intensities over a solar cycle are important for understanding how solar modulation affects galactic cosmic ray intensities and for separating the contributions of anomalous and galactic cosmic rays. The Cosmic Ray Isotope Spectrometer (CRIS) on ACE has been measuring cosmic ray isotopes, including helium, since 1997 with high statistical precision. We present helium elemental intensities between approx. 10 to approx. 100 MeV/nucleon from the Solar Isotope Spectrometer (SIS) and CRIS observations over a solar cycle and compare these results with the observations from other satellite and balloon-borne instruments, and with GCR transport and solar modulation models.

  6. Encore of the Bashful ballerina in solar cycle 23

    NASA Astrophysics Data System (ADS)

    Mursula, K.; Virtanen, I. I.

    2009-04-01

    The rotation averaged location of the heliospheric current sheet has been found to be shifted systematically southward for about three years in the late declining to minimum phase of the solar cycle. This behaviour, called by the concept of the Bashful ballerina, has earlier been shown to be valid at least during the active solar cycle of the last century since the late 1920s. Recently, Zhao et al have analysed the WSO observations and conclude that there is no southward coning in HCS or north-south difference in the heliospheric magnetic field during the late declining phase of solar cycle 23. In disagreement with these results, we find that there is a similar but smaller southward shift of the HCS and dominance of the northern field area as in all previous solar cycles. The present smaller asymmetry is in agreement with an earlier observation based on long-term geomagnetic activity that solar hemispheric asymmetry is larger during highly active solar cycles. Moreover, we connect the smallness of shift to the structure of the solar magnetic field with an exceptionally large tilt. We also discuss the cause of the differences between the two approaches reaching different conclusions.

  7. Proceedings of the 19th International Conference on Ion Beam Modification of Materials (IBMM 2014)

    NASA Astrophysics Data System (ADS)

    Vantomme, André; Temst, Kristiaan

    2015-12-01

    It is our pleasure to present the proceedings of the 19th International Conference on Ion Beam Modification of Materials, which took place from September 14th until September 19th, 2014. The conference was held in the historic center of Leuven, a medieval city in the heart of Europe, a city where centuries-old culture meets frontier science and technology. Among other places, the conference brought us to the University Hall, which has been in use by the university since its foundation in 1425, to the Infirmerie of the Grand Beguinage and to the medieval city of Bruges, the latter two being Unesco World Heritage sites.

  8. Forecasting decadal and shorter time-scale solar cycle features

    NASA Astrophysics Data System (ADS)

    Dikpati, Mausumi

    2016-07-01

    Solar energetic particles and magnetic fields reach the Earth through the interplanetary medium and affect it in various ways, producing beautiful aurorae, but also electrical blackouts and damage to our technology-dependent economy. The root of energetic solar outputs is the solar activity cycle, which is most likely caused by dynamo processes inside the Sun. It is a formidable task to accurately predict the amplitude, onset and peak timings of a solar cycle. After reviewing all solar cycle prediction methods, including empirical as well as physical model-based schemes, I will describe what we have learned from both validation and nonvalidation of cycle 24 forecasts, and how to refine the model-based schemes for upcoming cycle 25 forecasts. Recent observations indicate that within a solar cycle there are shorter time-scale 'space weather' features, such as bursts of various forms of activity with approximately one year periodicity. I will demonstrate how global tachocline dynamics could play a crucial role in producing such space weather. The National Center for Atmospheric Research is sponsored by the National Science Foundation.

  9. Solar cycle effect in SBUV/SBUV 2 ozone data

    NASA Astrophysics Data System (ADS)

    Gruzdev, Aleksandr

    Effect of the 11-year solar cycle on stratospheric ozone is analyzed using the data of ozone measurements with SBUV/SBUV 2 instruments aboard Nimbus 7, NOAA 9, NOAA 11, NOAA 14, NOAA 16, and NOAA 17-NOAA 19 satellites for 1978-2012 (ftp://toms.gsfc.nasa.gov/pub/sbuv/). High-resolution spectral and cross-spectral methods as well as the method of multiple linear regression were used for the analysis. The regression model takes into account the annual variation, the linear trend, the solar cycle effect and the effects on ozone of the products of the Pinatubo volcano eruption and the quasi-biennial oscillations in the equatorial stratospheric wind. The cross-spectral analysis of ozone concentration and 10.7 cm solar radio flux shows that, generally, 11-year ozone variations in the upper stratosphere and lower mesosphere lag behind while ozone variations in the low-latitude lower stratosphere lead the solar cycle. The phase shift between the ozone variations and the solar cycle reaches pi/2 in 35-40 km layer over the tropics and in the southern hemisphere lower stratosphere. Calculations show that taking into account the phase shift is especially important for correct estimation of the ozone response to the solar cycle in the tropical middle stratosphere. Local maxima of ozone sensitivity to the 11-year solar cycle are noted around a year below the stratopause (45-50 km), in 30-35 km layer in the middle stratosphere, and in the polar lower stratosphere. The sensitivity of the ozone response to the solar cycle for the whole period of 1978-2012 is less than that for the period of 1978-2003 which does not include the 24th solar cycle with anomalously small amplitude. The ozone response is seasonally dependent. Maximal amplitudes of the ozone response are characteristic for polar latitudes during winter-spring periods. For example ozone changes related to the solar cycle can reach 5% in the low and middle latitudes during the 1978-2012 period, while winter-spring ozone

  10. Trends and solar cycle effects in mesospheric ice clouds

    NASA Astrophysics Data System (ADS)

    Lübken, Franz-Josef; Berger, Uwe; Fiedler, Jens; Baumgarten, Gerd; Gerding, Michael

    Lidar observations of mesospheric ice layers (noctilucent clouds, NLC) are now available since 12 years which allows to study solar cycle effects on NLC parameters such as altitudes, bright-ness, and occurrence rates. We present observations from our lidar stations in Kuehlungsborn (54N) and ALOMAR (69N). Different from general expectations the mean layer characteris-tics at ALOMAR do not show a persistent anti-correlation with solar cycle. Although a nice anti-correlation of Ly-alpha and occurrence rates is detected in the first half of the solar cycle, occurrence rates decreased with decreasing solar activity thereafter. Interestingly, in summer 2009 record high NLC parameters were detected as expected in solar minimum conditions. The morphology of NLC suggests that other processes except solar radiation may affect NLC. We have recently applied our LIMA model to study in detail the solar cycle effects on tempera-tures and water vapor concentration the middle atmosphere and its subsequent influence on mesospheric ice clouds. Furthermore, lower atmosphere effects are implicitly included because LIMA nudges to the conditions in the troposphere and lower stratosphere. We compare LIMA results regarding solar cycle effects on temperatures and ice layers with observations at ALO-MAR as well as satellite borne measurements. We will also present LIMA results regarding the latitude variation of solar cycle and trends, including a comparison of northern and southern hemisphere. We have adapted the observation conditions from SBUV (wavelength and scatter-ing angle) in LIMA for a detailed comparison with long term observations of ice clouds from satellites.

  11. The dynamo basis of solar cycle precursor schemes

    NASA Astrophysics Data System (ADS)

    Charbonneau, Paul; Barlet, Guillaume

    2011-02-01

    We investigate the dynamo underpinning of solar cycle precursor schemes based on direct or indirect measures of the solar surface magnetic field. We do so for various types of mean-field-like kinematic axisymmetric dynamo models, where amplitude fluctuations are driven by zero-mean stochastic forcing of the dynamo number controlling the strength of the poloidal source term. In all stochastically forced models considered, the surface poloidal magnetic field is found to have precursor value only if it feeds back into the dynamo loop, which suggests that accurate determination of the magnetic flux budget of the solar polar fields may hold the key to dynamo model-based cycle forecasting.

  12. An early solar dynamo prediction: Cycle 23 is approximately cycle 22

    NASA Technical Reports Server (NTRS)

    Schatten, Kenneth H.; Pesnell, W. Dean

    1993-01-01

    In this paper, we briefly review the 'dynamo' and 'geomagnetic precursor' methods of long-term solar activity forecasting. These methods depend upon the most basic aspect of dynamo theory to predict future activity, future magnetic field arises directly from the magnification of pre-existing magnetic field. We then generalize the dynamo technique, allowing the method to be used at any phase of the solar cycle, through the development of the 'Solar Dynamo Amplitude' (SODA) index. This index is sensitive to the magnetic flux trapped within the Sun's convection zone but insensitive to the phase of the solar cycle. Since magnetic fields inside the Sun can become buoyant, one may think of the acronym SODA as describing the amount of buoyant flux. Using the present value of the SODA index, we estimate that the next cycle's smoothed peak activity will be about 210 +/- 30 solar flux units for the 10.7 cm radio flux and a sunspot number of 170 +/- 25. This suggests that solar cycle #23 will be large, comparable to cycle #22. The estimated peak is expected to occur near 1999.7 +/- 1 year. Since the current approach is novel (using data prior to solar minimum), these estimates may improve when the upcoming solar minimum is reached.

  13. Energization of pickup ions at terrestrial planets: From planet to planet, from solar cycle to solar cycle

    NASA Astrophysics Data System (ADS)

    Jarvinen, Riku; Kallio, Esa

    2014-05-01

    We discuss the pickup ion escape from the atmospheres of terrestrial planets in the Solar System. When upper atmospheric neutral planetary species are ionized in the solar wind at unmagnetized planets, they get accelerated by the solar wind flow and can escape from the atmosphere. We study in this work the energization of planetary ions in the solar wind at different heliospheric distances corresponding to Mercury, Venus, Earth and Mars. The analysis is based on the interplanetary Pioneer Venus Orbiter and OMNI solar wind datasets between 1978-1988. Using these datasets we derive statistics of the ExB drift velocities and Larmor radii of pickup ions at the terrestrial planets over a solar cycle. We find that the pickup ions are expected to be found on average at lower energies and at velocities more perpendicular to the solar wind flow the closer to the Sun a planet is due to the Parker spiral structure of the interplanetary magnetic field. Further, the energization and dynamics of the pickup ions vary considerably with the solar activity. The Larmor radii of the pickup ions are largest during a solar minimum while the pickup ion energies are highest during the declining phase of a solar cycle. References: Jarvinen R. and Kallio E., Energization of planetary pickup ions in the Solar System, J. Geophys. Res., accepted article, doi:10.1002/2013JE004534, 2014

  14. A solar cycle timing predictor - The latitude of active regions

    NASA Technical Reports Server (NTRS)

    Schatten, Kenneth H.

    1990-01-01

    A 'Spoerer butterfly' method is used to examine solar cycle 22. It is shown from the latitude of active regions that the cycle can now be expected to peak near November 1989 + or - 8 months, basically near the latter half of 1989.

  15. Solar Cycle: Magnetized March to Equator

    NASA Video Gallery

    Bands of magnetized solar material – with alternating south and north polarity – march toward the sun's equator. Comparing the evolution of the bands with the sunspot number in each hemisphere over...

  16. SOLAR CYCLE VARIATION OF THE INTER-NETWORK MAGNETIC FIELD

    SciTech Connect

    Jin, Chunlan; Wang, Jingxiu

    2015-06-20

    The solar inter-network magnetic field is the weakest component of solar magnetism, but it contributes most of the solar surface magnetic flux. The study of its origin has been constrained by the inadequate tempospatial resolution and sensitivity of polarization observations. With dramatic advances in spatial resolution and detecting sensitivity, the solar spectropolarimetry provided by the Solar Optical Telescope on board Hinode in an interval from the solar minimum to maximum of cycle 24 opens an unprecedented opportunity to study the cyclic behavior of the solar inter-network magnetic field. More than 1000 Hinode magnetograms observed from 2007 January to 2014 August are selected in the study. It has been found that there is a very slight correlation between sunspot number and magnetic field at the inter-network flux spectrum. From solar minimum to maximum of cycle 24, the flux density of the solar inter-network field is invariant, at 10 ± 1 G. The observations suggest that the inter-network magnetic field does not arise from flux diffusion or flux recycling of solar active regions, thereby indicating the existence of a local small-scale dynamo. Combining the full-disk magnetograms observed by the Solar and Heliospheric Observatory/Michelson Doppler Imager and the Solar Dynamics Observatory/Helioseismic and Magnetic Imager in the same period, we find that the area ratio of the inter-network region to the full disk of the Sun apparently decreases from solar minimum to maximum but always exceeds 60%, even in the phase of solar maximum.

  17. Solar Cycle in the Heliosphere and Cosmic Rays

    NASA Astrophysics Data System (ADS)

    Bazilevskaya, Galina A.; Cliver, Edward W.; Kovaltsov, Gennady A.; Ling, Alan G.; Shea, M. A.; Smart, D. F.; Usoskin, Ilya G.

    2014-12-01

    Manifestations of the 11-year solar cycle and longer time-scale variability in the heliosphere and cosmic rays are considered. We briefly review the cyclic variability of such heliospheric parameters as solar wind speed and density and heliospheric magnetic field, open magnetic flux and latitude variations of the heliospheric current sheet. It is discussed whether the local in-situ observation near Earth can represent the global 3D heliospheric pattern. Variability of cosmic rays near Earth provides an indirect useful tool to study the heliosphere. We discuss details of the heliospheric modulation of galactic cosmic rays, as recorded at and near Earth, and their relation to the heliospheric conditions in the outer heliosphere. On the other hand, solar energetic particles can serve as probes for explosive phenomena on the Sun and conditions in the corona and inner heliosphere. The occurrence of major solar proton events depicts an overall tendency to follow the solar cycle but individual events may appear at different phases of the solar cycle, as defined by various factors. The solar cycle in the heliosphere and cosmic rays depicts a complex pattern which includes different processes and cannot be described by a simple correlation with sunspot number.

  18. Variation of solar acoustic emission and its relation to phase of the solar cycle

    NASA Astrophysics Data System (ADS)

    Chen, Ruizhu; Zhao, Junwei

    2016-05-01

    Solar acoustic emission is closely related to solar convection and photospheric magnetic field. Variation of acoustic emission and its relation to the phase of solar cycles are important to understand dynamics of solar cycles and excitation of acoustic waves. In this work we use 6 years of SDO/HMI Dopplergram data to study acoustic emissions of the whole sun and of the quiet-sun regions, respectively, in multiple acoustic frequency bands. We show the variation of acoustic emission from May 2010 to April 2016, covering half of the solar cycle 24, and analyze its correlation with the solar activity level indexed by daily sunspot number and total magnetic flux. Results show that the correlation between the whole-Sun acoustic emission and the solar activity level is strongly negative for low frequencies between 2.5 and 4.5 mHz, but strongly positive for high frequencies between 4.5 and 6.0 mHz. For high frequencies, the acoustic emission excess in sunspot halos overwhelms the emission deficiency in sunspot umbrae and penumbrae. The correlation between the acoustic emission in quiet regions and the solar activity level is negative for 2.5-4.0 mHz and positive for 4.0-5.5 mHz. This shows that the solar background acoustic power, with active regions excluded, also varies during a solar cycle, implying the excitation frequencies or depths are highly related to the solar magnetic field.

  19. Circumcision of the Female Intellect: 19th Century Women Who Opposed Scholarly Education

    ERIC Educational Resources Information Center

    Holmes, Marbeth

    2009-01-01

    In 19th century America, some women decried the opportunity for scholarly education as rebellion against religion and predicted a grim decline in the quality of life, home, and hearth for American families and for American culture and politics. In particular, women who opposed scholarly education argued that God had not created men and women…

  20. Seriously Popular: Rethinking 19th-Century American Literature through the Teaching of Popular Fiction

    ERIC Educational Resources Information Center

    Gatti, Lauren

    2011-01-01

    Curious about the connections between the author's students' reading tastes and those of 19th-century readers, the author read Nina Baym's excellent text "Novels, Readers, and Reviewers: Responses to Fiction in Antebellum America" to gain a sense of how readers in the 1800s might have thought about the texts that they read. Nineteenth-century…

  1. Dancetime! 500 Years of Social Dance. Volume I: 15th-19th Centuries. [Videotape].

    ERIC Educational Resources Information Center

    Teten, Carol

    This VHS videotape recording is the first in a two-volume series that presents 500 years of social dance, music, and fashion. It focuses on the 15th-19th centuries, including Renaissance nobility, Baroque extravagance, Regency refinement, and Victorian romanticism. Each era reflects the changing relationships between men and women through the…

  2. Missionaries and Tonic Sol-fa Music Pedagogy in 19th-Century China

    ERIC Educational Resources Information Center

    Southcott, Jane E.; Lee, Angela Hao-Chun

    2008-01-01

    In the 19th century, Christian missionaries in China, as elsewhere, used the Tonic Sol-fa method of music instruction to aid their evangelizing. This system was designed to improve congregational singing in churches, Sunday schools and missions. The London Missionary Society and other evangelical groups employed the method. These missionaries took…

  3. 1. COPY OF A LATE 19TH CENTURY BUSINESS CARD FOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. COPY OF A LATE 19TH CENTURY BUSINESS CARD FOR A. ALEXANDER & SON FLOURING MILLS. CARD OWNED BY THOMAS R. WILSON. Photographer: Berni Rich, Score Photographers, September 1986. - Alexander's Grist Mill, Lock 37 on Ohio & Erie Canal, South of Cleveland, Valley View, Cuyahoga County, OH

  4. 29. View of Brooklyn Tower emerging behind 19th century commercial ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. View of Brooklyn Tower emerging behind 19th century commercial buildings on the corner of Front Street and Camden Plaza. Jet Lowe, photographer, 1982. - Brooklyn Bridge, Spanning East River between Park Row, Manhattan and Sands Street, Brooklyn, New York County, NY

  5. An Analysis of Environmental Issues in 19th Century England Using the Writings of Charles Dickens

    ERIC Educational Resources Information Center

    MacKenzie, Ann Haley

    2008-01-01

    Charles Dickens lived during the best and worst of times in 19th century England. His writings were greatly influenced by the ongoing industrial revolution. He described abhorrent environmental conditions, inadequate sanitary practices, child abuse, and other social maladies of the times. By bringing Charles Dickens into the biology classroom,…

  6. 4. Photocopy of old 19th century photo showing a steam ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Photocopy of old 19th century photo showing a steam engine in active use. Original photo in files of Insurance Company of North America, Philadelphia, Pa. Exact date not known. - Philadelphia Hose Company No. 1, Seventh & Filbert Streets, Philadelphia, Philadelphia County, PA

  7. Pacific Telecommunications Council Annual Conference Proceedings (19th, Honolulu, Hawaii, January 19-22, 1997).

    ERIC Educational Resources Information Center

    Wedemeyer, Dan J., Ed.; Nickelson, Richard, Ed.

    This PTC'97 volume contains papers presented at the 19th annual conference of the Pacific Telecommunications Council, "Pacific Connections: Policy and Technology in the Information Economy" (1997). Three super-session groupings--industry, policy, and technology--provide attendees with a conceptual foundation from which subsequent concurrent…

  8. 12. VIEW OF MERCHANTS' HOTEL IN MID 19th CENTURY, 'FOURTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF MERCHANTS' HOTEL IN MID- 19th CENTURY, 'FOURTH STREET, PHILA., WEST SIDE, FROM MARKET TO ARCH', as it appeared in The Baxter Panoramic Business Directory, Est. 1857 which is available for viewing at the Free Library of Philadelphia, in the Castner Collection, Philadelphia Vol. No. 12, 'Streets 1'. - Merchants' Hotel, 40-50 North Fourth Street, Philadelphia, Philadelphia County, PA

  9. Negative Numbers in the 18th and 19th Centuries: Phenomenology and Representations

    ERIC Educational Resources Information Center

    Maz-Machado, Alexander; Rico-Romero, Luis

    2009-01-01

    This article presents a categorization of the phenomena and representations used to introduce negative numbers in mathematics books published in Spain during the 18th and 19th centuries. Through a content analysis of fourteen texts which were selected for the study, we distinguished four phenomena typologies: physical, accounting, temporal and…

  10. Nathaniel Topliff Allen, Early Professional and 19th Century Risk Taker.

    ERIC Educational Resources Information Center

    Cadwallader, Lynn

    Nathaniel T. Allen's life (1823-1903) offers insights into 19th century professionalization of education in the United States. His independent political views set him apart as a strong-willed and dauntless supporter of equal education opportunity. Appointed by Horace Mann as principal of a model school connected with the first public normal school…

  11. [Rape and transgression. Forensic medicine and sexual morality in Spain in the 19th century].

    PubMed

    Carpena, Amalio Lorente

    2010-01-01

    The purpose of this paper is to analyse the importance of the contribution of the Spanish forensic medical discourse in the 19th century, and its application in cases of sexual harassment, to legitimize the sexual moral value of the time. For that reason we will analyse the main forensic medicine treaties edited in Spain during this century.

  12. Early 19th Century Music Pedagogy--German and English Connections

    ERIC Educational Resources Information Center

    Southcott, Jane E.

    2007-01-01

    Calls to improve congregational psalmody in 18th century England strongly influenced early music pedagogy. In the first decades of the 19th century English music educators, concerned with psalmody and music in charitable schools, looked to Germany for models of successful practice. The Musikalisches Schulgesangbuch (1826) by Carl Gotthelf Gläser…

  13. The Romantic Rhetoric of 19th Century Obituaries: "She Gave a Few Faint Gasps and Died."

    ERIC Educational Resources Information Center

    Agnew, Eleanor

    Scholars of writing, language, and culture will find a rich fund of research material in 19th-century obituaries which convey extensive details of the deceased's life through an elegant language reminiscent of an oral culture. In contrast to today's newspaper obituaries, which are business-like, tight-lipped, and entirely devoid of any details or…

  14. The Development of the Progressive in 19th Century English: A Quantitative Survey.

    ERIC Educational Resources Information Center

    Arnaud, Rene

    1998-01-01

    Expansion of the progressive (be+ing periphrastic form, where "be" is at the same time the copula and a statement of existence) was a major feature of modernization of the English verb system in the 19th century. A survey (1787-1880) of a collection of private letters, most from famous writers, reveals that linguistic factors played a small role…

  15. 12. Photocopy, BOYS' MILITARY BAND, mid or late 19th century. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Photocopy, BOYS' MILITARY BAND, mid or late 19th century. Original photograph at State Historical Society of North Dakota, file No. TF854 - Fort Totten, 12 miles southwest of Devils Lake City off Route 57, Devils Lake, Ramsey County, ND

  16. The Rise of Age Homogamy in 19th Century Western Europe

    ERIC Educational Resources Information Center

    van de Putte, Bart; Van Poppel, Frans; Vanassche, Sofie; Sanchez, Maria; Jidkova, Svetlana; Eeckhaut, Mieke; Oris, Michel; Matthijs, Koen

    2009-01-01

    In many parts of Western Europe the age at first marriage and the level of celibacy declined in the second half of the 19th century. This weakening of the European marriage pattern (EMP) can be interpreted as a "classic" response to the increase of the standard of living, but a more far-reaching interpretation is that the erosion of the EMP was…

  17. The Garbers: Using Digital History To Recreate a 19th-Century Family.

    ERIC Educational Resources Information Center

    Mason, Cheryl L.; Carter, Alice

    1999-01-01

    Describes a lesson in which students read a letter from the Web site "Valley of the Shadow: Two Communities during the American Civil War," an interactive archive of digitized primary sources. Students search the site's 1860 population census to learn about Thomas Garber and his family. Students also learn about life in the 19th century. (CMK)

  18. Mars Ion Outflow and Escape - Solar Cycle Dependence

    NASA Astrophysics Data System (ADS)

    Lundin, Rickard; Barabash, Stas; Nilsson, Hans; Yamauchi, Masatoshi; Dubinin, Edic

    2013-04-01

    With 9 years of data from the ASPERA-3 experiment on Mars Express (MEX) it is now feasible to analyze the solar cycle impact on the ion outflow and escape from Mars - from the end of solar cycle 23, through solar minimum 2008, up to the solar maximum of cycle 24. The study is based on average fluxes of low-energy (<300 eV) O+ and O2+, derived for selected periods when MEX traversed the central tail near the noon-midnight meridian. A time series plot of average O+ and O2+ fluxes, and solar activity proxies (RI and F10.7) display how the heavy ion outflow from Mars vary with solar activity. We note that the average O+, O2+ flux increased by a factor of ≈10 from 2008 (solar minimum) to 2013, while RI rose from ≈ 3 to 60, and a normalized F10.7* (F10.7-60) rose from ≈6 - 60, F10.7* suggesting a close correlation with heavy ion outflow. A correlation analysis between the two solar activity proxies (RI and F10.7*) and the O+ and O2+ average flux gives correlation coefficients (R2) greater than 0.6, i.e. there is a strong positive correlation between the energization and outflow of ionospheric heavy ions and solar activity. A preliminary estimate of the total escape rate of heavy ions (O++O2+) from Mars is ≈1-2·1024 ions/s (2008, solar minimum) and 1-2·1025 ions/s (2013, solar maximum?)

  19. The solar cycle variation of coronal mass ejections and the solar wind mass flux

    NASA Technical Reports Server (NTRS)

    Webb, David F.; Howard, Russell A.

    1994-01-01

    Coronal mass ejections (CMEs) are an important aspect of coronal physics and a potentially significant contributor to perturbations of the solar wind, such as its mass flux. Sufficient data on CMEs are now available to permit study of their longer-term occurrency patterns. Here we present the results of a study of CME occurrence rates over more than a complete 11-year solar sunspot cycle and a comparison of these rates with those of other activity related to CMEs and with the solar wind particle flux at 1 AU. The study includes an evaluation of correlations to the CME rates, which include instrument duty cycles, visibility functions, mass detection thresholds, and geometrical considerations. The main results are as follows: (1) The frequency of occurrence of CMEs tends to track the solar activity cycle in both amplitude and phase; (2) the CME rates from different instruments, when corrected for both duty cycles and visibility functions, are reasonably consistent; (3) considering only longer-term averages, no one class of solar activity is better correlated with CME rate than any other; (4) the ratio of the annualized CME to solar wind mass flux tends to track the solar cycle; and (5) near solar maximum, CMEs can provide a significant fraction (i.e., approximately equals 15%) of the average mass flux to the near-ecliptic solar wind.

  20. WHAT CAUSES THE INTER-SOLAR-CYCLE VARIATION OF TOTAL SOLAR IRRADIANCE?

    SciTech Connect

    Xiang, N. B.; Kong, D. F.

    2015-12-15

    The Physikalisch Meteorologisches Observatorium Davos total solar irradiance (TSI), Active Cavity Radiometer Irradiance Monitoring TSI, and Royal Meteorological Institute of Belgium TSI are three typical TSI composites. Magnetic Plage Strength Index (MPSI) and Mount Wilson Sunspot Index (MWSI) should indicate the weak and strong magnetic field activity on the solar full disk, respectively. Cross-correlation (CC) analysis of MWSI with three TSI composites shows that TSI should be weakly correlated with MWSI, and not be in phase with MWSI at timescales of solar cycles. The wavelet coherence (WTC) and partial wavelet coherence (PWC) of TSI with MWSI indicate that the inter-solar-cycle variation of TSI is also not related to solar strong magnetic field activity, which is represented by MWSI. However, CC analysis of MPSI with three TSI composites indicates that TSI should be moderately correlated and accurately in phase with MPSI at timescales of solar cycles, and that the statistical significance test indicates that the correlation coefficient of three TSI composites with MPSI is statistically significantly higher than that of three TSI composites with MWSI. Furthermore, the cross wavelet transform (XWT) and WTC of TSI with MPSI show that the TSI is highly related and actually in phase with MPSI at a timescale of a solar cycle as well. Consequently, the CC analysis, XWT, and WTC indicate that the solar weak magnetic activity on the full disk, which is represented by MPSI, dominates the inter-solar-cycle variation of TSI.

  1. Prediction of Solar Activity from Solar Background Magnetic Field Variations in Cycles 21-23

    NASA Astrophysics Data System (ADS)

    Shepherd, Simon J.; Zharkov, Sergei I.; Zharkova, Valentina V.

    2014-11-01

    A comprehensive spectral analysis of both the solar background magnetic field (SBMF) in cycles 21-23 and the sunspot magnetic field in cycle 23 reported in our recent paper showed the presence of two principal components (PCs) of SBMF having opposite polarity, e.g., originating in the northern and southern hemispheres, respectively. Over a duration of one solar cycle, both waves are found to travel with an increasing phase shift toward the northern hemisphere in odd cycles 21 and 23 and to the southern hemisphere in even cycle 22. These waves were linked to solar dynamo waves assumed to form in different layers of the solar interior. In this paper, for the first time, the PCs of SBMF in cycles 21-23 are analyzed with the symbolic regression technique using Hamiltonian principles, allowing us to uncover the underlying mathematical laws governing these complex waves in the SBMF presented by PCs and to extrapolate these PCs to cycles 24-26. The PCs predicted for cycle 24 very closely fit (with an accuracy better than 98%) the PCs derived from the SBMF observations in this cycle. This approach also predicts a strong reduction of the SBMF in cycles 25 and 26 and, thus, a reduction of the resulting solar activity. This decrease is accompanied by an increasing phase shift between the two predicted PCs (magnetic waves) in cycle 25 leading to their full separation into the opposite hemispheres in cycle 26. The variations of the modulus summary of the two PCs in SBMF reveals a remarkable resemblance to the average number of sunspots in cycles 21-24 and to predictions of reduced sunspot numbers compared to cycle 24: 80% in cycle 25 and 40% in cycle 26.

  2. Prediction of solar activity from solar background magnetic field variations in cycles 21-23

    SciTech Connect

    Shepherd, Simon J.; Zharkov, Sergei I.; Zharkova, Valentina V. E-mail: s.zharkov@hull.ac.uk

    2014-11-01

    A comprehensive spectral analysis of both the solar background magnetic field (SBMF) in cycles 21-23 and the sunspot magnetic field in cycle 23 reported in our recent paper showed the presence of two principal components (PCs) of SBMF having opposite polarity, e.g., originating in the northern and southern hemispheres, respectively. Over a duration of one solar cycle, both waves are found to travel with an increasing phase shift toward the northern hemisphere in odd cycles 21 and 23 and to the southern hemisphere in even cycle 22. These waves were linked to solar dynamo waves assumed to form in different layers of the solar interior. In this paper, for the first time, the PCs of SBMF in cycles 21-23 are analyzed with the symbolic regression technique using Hamiltonian principles, allowing us to uncover the underlying mathematical laws governing these complex waves in the SBMF presented by PCs and to extrapolate these PCs to cycles 24-26. The PCs predicted for cycle 24 very closely fit (with an accuracy better than 98%) the PCs derived from the SBMF observations in this cycle. This approach also predicts a strong reduction of the SBMF in cycles 25 and 26 and, thus, a reduction of the resulting solar activity. This decrease is accompanied by an increasing phase shift between the two predicted PCs (magnetic waves) in cycle 25 leading to their full separation into the opposite hemispheres in cycle 26. The variations of the modulus summary of the two PCs in SBMF reveals a remarkable resemblance to the average number of sunspots in cycles 21-24 and to predictions of reduced sunspot numbers compared to cycle 24: 80% in cycle 25 and 40% in cycle 26.

  3. Solar cycle effects of spectrally varying solar irradiance in a coupled chemistry--climate model

    NASA Astrophysics Data System (ADS)

    Swartz, W. H.; Stolarski, R. S.; Oman, L.; Fleming, E. L.; Jackman, C. H.

    2010-12-01

    Variation of the solar spectral irradiance (SSI) with solar cycle impacts the composition and temperature of the atmosphere. Stratosphere ozone and temperature, for example, respond through both direct solar heating and photolysis. We have implemented an 11-year solar cycle in the Goddard Earth Observing System Chemistry--Climate Model (GEOS CCM). One of the SSI datasets used is a multi-decadal historical reconstruction based on contemporary observations of solar irradiance and historical proxies for solar activity. We examine the atmospheric response to SSI variations through direct solar heating and photolysis individually and also when coupled in the model. Ozone response is dominated by photolysis, whereas both direct heating and photolysis affect stratospheric temperatures approximately equally. We also find that the magnitude of the atmospheric response is sensitive to the spectral characteristics of the SSI dataset used.

  4. Evolution of solar wind turbulence and intermittency over the solar cycle

    NASA Astrophysics Data System (ADS)

    Väisänen, Pauli; Virtanen, Ilpo; Echim, Marius; Munteanu, Costel; Mursula, Kalevi

    2016-04-01

    Solar wind is a natural, near-by plasma physics laboratory, which offers possibilities to study plasma physical phenomena over a wide range of parameter values that are difficult to reach in ground-based laboratories. Accordingly, the solar wind is subject of many studies of, e.g., intermittency, turbulence and other nonlinear space plasma phenomena. Turbulence is an important feature of the solar wind dynamics, e.g., for the energy transfer mechanisms and their scale invariance, the solar wind evolution, the structure of the heliospheric magnetic field (HMF), the particle energization and heating, and for phenomena related to solar wind interaction with the planetary plasma systems. Here we analyse high resolution measurements of the solar wind and the heliospheric magnetic field provided by several ESA and NASA satellites, including ACE, STEREO, Ulysses and Cluster. This collection of satellites allows us to compile and study nearly 20 years of high-resolution solar wind and HMF measurements from the start of solar cycle 23 to the current declining phase of solar cycle 24. Long-term studies require homogeneity and, therefore, we pay great attention to the reliability and consistency of the data, in particular to instrumental defects like spin harmonics, the purity of the solar wind and its possible contamination in the foreshock by magnetospheric ions. We study how the different key-descriptors of turbulence like the slope of the power law of power spectral density and the kurtosis of the fluctuations of the heliospheric magnetic field vary over the solar cycle.

  5. Interannual Variations of MLS Carbon Monoxide Induced by Solar Cycle

    NASA Technical Reports Server (NTRS)

    Lee, Jae N.; Wu, Dong L.; Ruzmaikin, Alexander

    2013-01-01

    More than eight years (2004-2012) of carbon monoxide (CO) measurements from the Aura Microwave Limb Sounder (MLS) are analyzed. The mesospheric CO, largely produced by the carbon dioxide (CO2) photolysis in the lower thermosphere, is sensitive to the solar irradiance variability. The long-term variation of observed mesospheric MLS CO concentrations at high latitudes is likely driven by the solar-cycle modulated UV forcing. Despite of different CO abundances in the southern and northern hemispheric winter, the solar-cycle dependence appears to be similar. This solar signal is further carried down to the lower altitudes by the dynamical descent in the winter polar vortex. Aura MLS CO is compared with the Solar Radiation and Climate Experiment (SORCE) total solar irradiance (TSI) and also with the spectral irradiance in the far ultraviolet (FUV) region from the SORCE Solar-Stellar Irradiance Comparison Experiment (SOLSTICE). Significant positive correlation (up to 0.6) is found between CO and FUVTSI in a large part of the upper atmosphere. The distribution of this positive correlation in the mesosphere is consistent with the expectation of CO changes induced by the solar irradiance variations.

  6. A Solar Cycle Dependence of Nonlinearity in Magnetospheric Activity

    SciTech Connect

    Johnson, Jay R; Wing, Simon

    2005-03-08

    The nonlinear dependencies inherent to the historical K(sub)p data stream (1932-2003) are examined using mutual information and cumulant based cost as discriminating statistics. The discriminating statistics are compared with surrogate data streams that are constructed using the corrected amplitude adjustment Fourier transform (CAAFT) method and capture the linear properties of the original K(sub)p data. Differences are regularly seen in the discriminating statistics a few years prior to solar minima, while no differences are apparent at the time of solar maximum. These results suggest that the dynamics of the magnetosphere tend to be more linear at solar maximum than at solar minimum. The strong nonlinear dependencies tend to peak on a timescale around 40-50 hours and are statistically significant up to one week. Because the solar wind driver variables, VB(sub)s and dynamical pressure exhibit a much shorter decorrelation time for nonlinearities, the results seem to indicate that the nonlinearity is related to internal magnetospheric dynamics. Moreover, the timescales for the nonlinearity seem to be on the same order as that for storm/ring current relaxation. We suggest that the strong solar wind driving that occurs around solar maximum dominates the magnetospheric dynamics suppressing the internal magnetospheric nonlinearity. On the other hand, in the descending phase of the solar cycle just prior to solar minimum, when magnetospheric activity is weaker, the dynamics exhibit a significant nonlinear internal magnetospheric response that may be related to increased solar wind speed.

  7. Performance evaluation of space solar Brayton cycle power systems

    NASA Astrophysics Data System (ADS)

    Diao, Zheng-Gang

    1992-06-01

    Unlike gas turbine power systems which consume chemical or nuclear energy, the energy consumption and/or cycle efficiency should not be a suitable criterion for evaluating the performance of space solar Brayton cycle power. A new design goal, life cycle cost, can combine all the power system characteristics, such as mass, area, and station-keeping propellant, into a unified criterion. Effects of pressure ratio, recuperator effectiveness, and compressor inlet temperature on life cycle cost were examined. This method would aid in making design choices for a space power system.

  8. Solar-Cycle Variations of the Differential Rotation and Tachocline

    NASA Astrophysics Data System (ADS)

    Howe, R.

    2002-05-01

    Over the past several years, helioseismic data from the Michelson Doppler Imager aboard the SOHO spacecraft, and from the Global Oscillation Network Group, have allowed us to study the changing dynamics of the solar convection zone in greater detail than ever before. We now know that the zonal flows of the so-called torsional oscillation extend well into the convection zone though apparently not to its base, and there seem to be rotation variations of a shorter period around the tachocline region which is crucial to theories of the solar cycle. At higher latitudes, the rotation rate varies strongly during the solar cycle. Modeling and simulation studies attempt to reproduce this behavior with varying degrees of success. The National Solar Observatory is operated by the Association of Universities for Research in Astronomy (AURA), under a cooperative agreement with the National Science Foundation. This work was partly supported by NASA contract S-92698-F.

  9. Rapid thermal cycling of new technology solar array blanket coupons

    NASA Technical Reports Server (NTRS)

    Scheiman, David A.; Smith, Bryan K.; Kurland, Richard M.; Mesch, Hans G.

    1990-01-01

    NASA Lewis Research Center is conducting thermal cycle testing of a new solar array blanket technologies. These technologies include test coupons for Space Station Freedom (SSF) and the advanced photovoltaic solar array (APSA). The objective of this testing is to demonstrate the durability or operational lifetime of the solar array interconnect design and blanket technology within a low earth orbit (LEO) or geosynchronous earth orbit (GEO) thermal cycling environment. Both the SSF and the APSA array survived all rapid thermal cycling with little or no degradation in peak performance. This testing includes an equivalent of 15 years in LEO for SSF test coupons and 30 years of GEO plus ten years of LEO for the APSA test coupon. It is concluded that both the parallel gap welding of the SSF interconnects and the soldering of the APSA interconnects are adequately designed to handle the thermal stresses of space environment temperature extremes.

  10. Solar rotation and the sunspot cycle

    NASA Technical Reports Server (NTRS)

    Hathaway, David H.; Wilson, Robert M.

    1990-01-01

    Reexamination of the published sunspot rotation rates from Mount Wilson for the period from 1921 to 1982 suggests that the sun rotates more rapidly when there are fewer sunspots. This behavior is seen over the course of each cycle with the most rapid rotation usually observed at sunspot minimum. It is also seen in hemispheric differences with the southern hemisphere, having fewer spots, rotating more rapidly than the northern hemisphere. Furthermore, the rotation rate averaged over each cycle also shows that the sun rotates more rapidly during cycles with fewer sunspots and less sunspots area. This inverse correlation between sunspot area and rotation rate suggests that during the Maunder minimum the sun may have rotated slightly faster than is observed today.

  11. Solar neutron decay proton observations in cycle 21

    NASA Technical Reports Server (NTRS)

    Evenson, Paul; Kroeger, Richard; Meyer, Peter; Reames, Donald

    1990-01-01

    Measurement of the flux and energy spectrum of the protons resulting from the decay of solar flare neutrons gives unique information on the spectrum of neutrons from 5 to 200 MeV. Neutrons from three flares have been observed in this manner during solar cycle 21. The use of the decay protons to determine neutron energy spectra is reviewed, and new and definitive energy spectra are presented for the two large flares on June 3, 1982 and April 25, 1984.

  12. Investigating the Causes of Solar-Cycle Variations in Solar Energetic Particle Fluences and Composition

    NASA Astrophysics Data System (ADS)

    Mewaldt, Richard; Cohen, Christina; Mason, Glenn M.; von Rosenvinge, Tycho; Li, Gang; Smith, Charles; Vourlidas, Angelos

    2015-04-01

    Measurements with ACE, STEREO, and GOES show that the number of large Solar Energetic Particle (SEP) events in solar cycle 24 is reduced by a factor of ~2 compared to this point of cycle 23, while the fluences of >10 MeV/nuc ions from H to Fe are reduced by factors ranging from ~4 to ~10. We investigate the origin of these cycle-to-cycle differences by evaluating possible factors that include properties of the associated CMEs, seed particle densities, and the interplanetary magnetic field strength and turbulence levels. These properties will be evaluated in the context of existing SEP acceleration models.

  13. THREE-DIMENSIONAL EVOLUTION OF SOLAR WIND DURING SOLAR CYCLES 22-24

    SciTech Connect

    Manoharan, P. K.

    2012-06-01

    This paper presents an analysis of three-dimensional evolution of solar wind density turbulence and speed at various levels of solar activity between solar cycles 22 and 24. The solar wind data used in this study have been obtained from the interplanetary scintillation (IPS) measurements made at the Ooty Radio Telescope, operating at 327 MHz. Results show that (1) on average, there was a downward trend in density turbulence from the maximum of cycle 22 to the deep minimum phase of cycle 23; (2) the scattering diameter of the corona around the Sun shrunk steadily toward the Sun, starting from 2003 to the smallest size at the deepest minimum, and it corresponded to a reduction of {approx}50% in the density turbulence between the maximum and minimum phases of cycle 23; (3) the latitudinal distribution of the solar wind speed was significantly different between the minima of cycles 22 and 23. At the minimum phase of solar cycle 22, when the underlying solar magnetic field was simple and nearly dipole in nature, the high-speed streams were observed from the poles to {approx}30 Degree-Sign latitudes in both hemispheres. In contrast, in the long-decay phase of cycle 23, the sources of the high-speed wind at both poles, in accordance with the weak polar fields, occupied narrow latitude belts from poles to {approx}60 Degree-Sign latitudes. Moreover, in agreement with the large amplitude of the heliospheric current sheet, the low-speed wind prevailed in the low- and mid-latitude regions of the heliosphere. (4) At the transition phase between cycles 23 and 24, the high levels of density and density turbulence were observed close to the heliospheric equator and the low-speed solar wind extended from the equatorial-to-mid-latitude regions. The above results in comparison with Ulysses and other in situ measurements suggest that the source of the solar wind has changed globally, with the important implication that the supply of mass and energy from the Sun to the interplanetary

  14. A Statistical Test of Uniformity in Solar Cycle Indices

    NASA Technical Reports Server (NTRS)

    Hathaway David H.

    2012-01-01

    Several indices are used to characterize the solar activity cycle. Key among these are: the International Sunspot Number, the Group Sunspot Number, Sunspot Area, and 10.7 cm Radio Flux. A valuable aspect of these indices is the length of the record -- many decades and many (different) 11-year cycles. However, this valuable length-of-record attribute has an inherent problem in that it requires many different observers and observing systems. This can lead to non-uniformity in the datasets and subsequent erroneous conclusions about solar cycle behavior. The sunspot numbers are obtained by counting sunspot groups and individual sunspots on a daily basis. This suggests that the day-to-day and month-to-month variations in these numbers should follow Poisson Statistics and be proportional to the square-root of the sunspot numbers themselves. Examining the historical records of these indices indicates that this is indeed the case - even with Sunspot Area and 10.7 cm Radio Flux. The ratios of the RMS variations to the square-root of the indices themselves are relatively constant with little variation over the phase of each solar cycle or from small to large solar cycles. There are, however, important step-like changes in these ratios associated with changes in observer and/or observer system. Here we show how these variations can be used to construct more uniform datasets.

  15. SOLAR ROTATION RATE DURING THE CYCLE 24 MINIMUM IN ACTIVITY

    SciTech Connect

    Antia, H. M.; Basu, Sarbani E-mail: sarbani.basu@yale.ed

    2010-09-01

    The minimum of solar cycle 24 is significantly different from most other minima in terms of its duration as well as its abnormally low levels of activity. Using available helioseismic data that cover epochs from the minimum of cycle 23 to now, we study the differences in the nature of the solar rotation between the minima of cycles 23 and 24. We find that there are significant differences between the rotation rates during the two minima. There are differences in the zonal-flow pattern too. We find that the band of fast rotating region close to the equator bifurcated around 2005 and recombined by 2008. This behavior is different from that during the cycle 23 minimum. By autocorrelating the zonal-flow pattern with a time shift, we find that in terms of solar dynamics, solar cycle 23 lasted for a period of 11.7 years, consistent with the result of Howe et al. (2009). The autocorrelation coefficient also confirms that the zonal-flow pattern penetrates through the convection zone.

  16. Solar cycle variation of thermospheric NO - A model sensitivity study

    NASA Astrophysics Data System (ADS)

    Kuze, A.; Ogawa, T.

    A one-dimensional numerical model which simulates diurnal and solar cycle variations of NO is studied to determine whether or not it can reproduce the NO profiles observed with rockets at various phases of solar activity. The transport effect by tidal winds are also discussed. The importance of various reactions to NO density profiles are determined. A calculation of the thermospheric temperature shows that the observed NO profiles modify the thermopause temperature by about 200 K at solar maximum, and that they are consistent with the variation of the thermospheric temperature.

  17. "Le Droit de L'Enfant:" Ideologies of the Child in 19th Century French Literature and Child Welfare Reform.

    ERIC Educational Resources Information Center

    Kirschner, Suzanne

    This paper examines ideological themes present in movements for child labor reform and in literature in 19th century France. Separate sections cover early industrialization and child labor reform, the image of the romantic child in French literature, and ideology and reforms. By the mid-19th century, England, America, and France all had their…

  18. The Measurement of the Solar Spectral Irradiance Variability during the Solar Cycle 24 using SOLAR/SOLSPEC on ISS

    NASA Astrophysics Data System (ADS)

    Bolsée, David; Pereira, Nuno; Pandey, Praveen; Cessateur, Gaël; Gillotay, Didier; Foujols, Thomas; Hauchecorne, Alain; Bekki, Slimane; Marchand, Marion; Damé, Luc; Meftah, Mustapha; Bureau, Jerôme

    2016-04-01

    Since April 2008, SOLAR/SOLSPEC measures the Solar Spectral Irradiance (SSI) from 166 nm to 3088 nm. The instrument is a part of the Solar Monitoring Observatory (SOLAR) payload, externally mounted on the Columbus module of the International Space Station. As the SSI is a key input for the validation of solar physics models, together with playing a role in the climate system and photochemistry of the Earth atmosphere, SOLAR/SOLSPEC spectral measurements becomes important. In this study, the in-flight operations and performances of the instrument -including the engineering corrections- will be presented for seven years of the SOLAR mission. Following an accurate absolute calibration, the SSI variability in the UV as measured by SOLAR/SOLSPEC in the course of the solar cycle 24 will be presented and compared to other instruments. The accuracy of these measurements will be also discussed here.

  19. Modeling the heliospheric current sheet: Solar cycle variations

    NASA Astrophysics Data System (ADS)

    Riley, Pete; Linker, J. A.; Mikić, Z.

    2002-07-01

    In this report we employ an empirically driven, three-dimensional MHD model to explore the evolution of the heliospheric current sheet (HCS) during the course of the solar cycle. We compare our results with a simpler ``constant-speed'' approach for mapping the HCS outward into the solar wind to demonstrate that dynamic effects can substantially deform the HCS in the inner heliosphere (<~5 AU). We find that these deformations are most pronounced at solar minimum and become less significant at solar maximum, when interaction regions are less effective. Although solar maximum is typically associated with transient, rather than corotating, processes, we show that even under such conditions, the HCS can maintain its structure over the course of several solar rotations. While the HCS may almost always be topologically equivalent to a ``ballerina skirt,'' we discuss an interval approaching the maximum of solar cycle 23 (Carrington rotations 1960 and 1961) when the shape would be better described as ``conch shell''-like. We use Ulysses magnetic field measurements to support the model results.

  20. A brief history of tuberculosis in Iran during the 19th and 20th centuries.

    PubMed

    Azizi, Mohammad Hossein; Bahadori, Moslem

    2011-05-01

    The history of tuberculosis as a worldwide fatal illness traces back to antiquity, a well-known disease in ancient civilizations. However, its causative agent remained unidentified until the last decades of the 19th century, when discovered by Robert Koch. In due course, preparation of the BCG vaccine, application of the Mantoux intradermal diagnostic tuberculosis test and administration of proper antituberculosis medications eventually controlled tuberculosis. However, despite these significant advancements tuberculosis remained uneradicated, particularly in developing countries after the emergence of both multidrug-resistant tuberculosis and HIV co-infection. Presented here, is a brief review of the history of tuberculosis in the world as well as its historical background in Iran, mainly during the 19th and 20th centuries.

  1. Enamel hypoplasia and age at weaning in 19th-century Florence, Italy.

    PubMed

    Moggi-Cecchi, J; Pacciani, E; Pinto-Cisternas, J

    1994-03-01

    A sample representing a population of the Florence district of middle 19th century was studied to determine the age of occurrence of enamel hypoplasias. The age interval most affected was that between 1.5 and 3.5 years. Historical sources on weaning habits of 19th-century Italian populations indicate a weaning period between 12 and 18 months. This is in agreement with the data on enamel defects, showing that children of post-weaning age are more subject to stress. Wide "grooves", with prolonged duration, are concentrated between 2 and 2.5 years, whereas "lines" occur primarily between 2.5 and 3 years. We suggest that this distribution could reflect the gradual introduction of dietary supplements until weaning is complete. PMID:8042693

  2. Physics education in the Greek community schools of Istanbul (19th century). The books

    NASA Astrophysics Data System (ADS)

    Lazos, Panayotis; Vlahakis, George N.

    2016-03-01

    During the 19th century a number of elementary and high schools were established for the need of the Greek community of Istanbul. Among the courses included in the curricula were those concerning the scientific study of Nature like Botany, Chemistry and Physics. In the present study we attempt to give a thorough description of the educational material used in these schools for the study of natural sciences with an emphasis in Physics. Especially we shall discuss the books used as course books as well as their probable sources. Furthermore we shall try to make a comparison with the relevant situation in the Greek state and the Ottoman Empire, where modern physics had been already introduced through textbooks based on Ganot's treatise on Physics. The results of our research will give for the first time a picture of the way Greek students in the 19th century Istanbul received their basic knowledge about Physics.

  3. [Criminology and superstition at the turn of the 19th century].

    PubMed

    Bachhiesl, Christian

    2012-01-01

    Criminology, which institutionalised at university level at the turn of the 19th century, was intensively engaged in the exploration of superstition. Criminologists investigated the various phenomena of superstition and the criminal behaviour resulting from it. They discovered bizarre (real or imagined) worlds of thought and mentalities, which they subjected to a rationalistic regime of interpretation in order to arrive at a better understanding of offences and crimes related to superstition. However, they sometimes also considered the use of occultist practices such as telepathy and clairvoyance to solve criminal cases. As a motive for committing homicide superstition gradually became less relevant in the course of the 19th century. Around 1900, superstition was accepted as a plausible explanation in this context only if a psychopathic form of superstition was involved. In the 20th century, superstition was no longer regarded as an explanans but an explanandum.

  4. Bilingualism and memory: early 19th century ideas about the significance of polyglot aphasia.

    PubMed

    Lorch, Marjorie

    2007-07-01

    In the second half of the 19th century, there was very little attention given to bilingual speakers within the growing clinical literature on aphasia. The first major publication on this topic (Pitres, 1895), appeared three decades after Broca's seminal work. Previously, Ribot (1881) had discussed the phenomenon of bilingual aphasia in the context of diseases of memory. Although interest in the neurological basis of the language faculty was in fact present throughout the century, the theoretical implications of the knowledge of more than one language did not appear to be linked to this issue. A number of British authors writing in the first half of the 19th century have been identified who did consider the significance of these cases. Importantly, these writers speculated on the implication of bilingual aphasia specifically with regard to ideas about memory rather than language. Consideration of these writings helps to illuminate the history of ideas about the organization of language in the brain. PMID:17715800

  5. Bilingualism and memory: early 19th century ideas about the significance of polyglot aphasia.

    PubMed

    Lorch, Marjorie

    2007-07-01

    In the second half of the 19th century, there was very little attention given to bilingual speakers within the growing clinical literature on aphasia. The first major publication on this topic (Pitres, 1895), appeared three decades after Broca's seminal work. Previously, Ribot (1881) had discussed the phenomenon of bilingual aphasia in the context of diseases of memory. Although interest in the neurological basis of the language faculty was in fact present throughout the century, the theoretical implications of the knowledge of more than one language did not appear to be linked to this issue. A number of British authors writing in the first half of the 19th century have been identified who did consider the significance of these cases. Importantly, these writers speculated on the implication of bilingual aphasia specifically with regard to ideas about memory rather than language. Consideration of these writings helps to illuminate the history of ideas about the organization of language in the brain.

  6. The tympanostomy tube: an ingenious invention of the mid 19th century.

    PubMed

    Mudry, Albert

    2013-02-01

    The introduction of the tympanostomy tube in the treatment of otitis media with effusion in the mid 20th century completely revolutionized its therapy. Nevertheless, it was not a new idea. The aim of this research is to elucidate the origin of prosthetic middle ear ventilation in the mid 19th century. A review of primary sources revealed at least seven different models of tympanostomy tube which were manufactured between 1845 and 1875. These included: Frank's gold tube, Lincke's rubber tube, Bonnafont's silver cannula, Politzer's hard rubber drain, Miot's metallic eyelet, Voltolini's gold ring, and Bonnafont's eyelet. Study of these early innovations shows that all of the technical and surgical principles of the tympanostomy tube were known in the mid 19th century. Widespread introduction into otological practice did not occur until the mid 20th century invention of the operating microscope. PMID:23183195

  7. [The teaching of history of medicine in Paris in the 19th century (1794-1914)].

    PubMed

    Galanopoulos, Philippe

    2010-06-01

    The defeat of the erudition which characterised the teaching of history of medicine at the end of the 19th Century, was a sign of the passing of one culture to another. This article examines two aspects of Parisian teaching, the institutional and the educational. In addition the question of the usefulness of this teaching is examined, both in relation to Paris and also to the whole field of French medicine.

  8. Proceedings of the 19th annual meeting of the Adhesion Society

    SciTech Connect

    Ward, T.C.

    1996-12-31

    This is the proceedings of the 19th Annual Meeting of the Adhesion Society, held February 18-21, 1996. Papers are presented on various aspects of adhesion, ranging from studies at the molecular level, to studies of the intermixing of polymer chains across interface joints, to the study of polymer/metal joints. Separate abstracts of articles from this proceedings have been indexed into the database.

  9. [Developments and trends in 19th- and 20th-century German nursing historiography].

    PubMed

    Schweikardt, Christoph

    2004-01-01

    This paper analyses important trends in 19th- and 20th-century German nursing historiography. Frequently, the diverse contributions, which were predominantly written by physicians and nurses, were strongly shaped by the occupational background of the author and purposes of professional politics. In recent years, valuable scholarly contributions on nursing organisations have appeared. Anglo-American nursing history research should serve as a model for Germany. The paper calls for the extension of a recently founded nursing history research network.

  10. New characteristics of the solar cycle and dynamo theory

    NASA Astrophysics Data System (ADS)

    Otkidychev, P. A.; Popova, E. P.

    2015-06-01

    Based on an analysis of the observational data for solar cycles 12-23 (Royal Greenwich Observatory-USAF/NOAA Sunspot Data), we have studied various parameters of the "Maunder butterflies." Based on the observational data for cycles 16-23, we have found that BT/ Land S depend linearly on each other, where B is the mean magnetic field of the cycle, T is the cycle duration, S is the cycle strength, and L is the mean sunspot latitude in the cycle (the arithmetic mean of the absolute values of the mean latitudes in the north and south). The connection of the observed quantities with the α- ω-dynamo theory is discussed.

  11. Solar large-scale positive polarity magnetic fields and geomagnetic disturbances

    NASA Technical Reports Server (NTRS)

    Bumba, V.

    1972-01-01

    Unlike the negative polarity solar magnetic field large-scale regular features that correlate with enhanced solar activity regions, the positive polarity regular formations formed in the weak and old background magnetic fields seem to correlate well with geomagnetically enhanced periods of time (shifted for 4 days), which means that they seem to be the source of the quiet solar wind. This behavior of the large intervals of heliographic longitude with prevailing positive polarity fields may be followed to the end of the 18th cycle, during the declining part of the 19th cycle, and during the first half of the present 20th cycle of solar activity.

  12. Solar Cycle Variations and Equatorial Oscillations: Modeling Study

    NASA Technical Reports Server (NTRS)

    Mayr, H. G.; Mengel, J. G.; Drob, D. P.; Chan, K. L.; Porter, H. S.; Bhartia, P. K. (Technical Monitor)

    2001-01-01

    Solar cycle activity effects (SCAE) in the lower and middle atmosphere, reported in several studies, are difficult to explain on the basis of the small changes in solar radiation that accompany the 11-year cycle, It is therefore natural to speculate that dynamical processes may come into play to produce a leverage. Such a leverage may be provided by the Quasi-Biennial Oscillation (QBO) in the zonal circulation of the stratosphere, which has been linked to solar activity variations. Driven primarily by wave mean flow interaction, the QBO period and its amplitude are variable but are also strongly influenced by the seasonal cycle in the solar radiation. This influence extends to low altitudes referred to as "downward control". Relatively small changes in solar radiative forcing can produce small changes in the period and phase of the QBO, but this in turn can produce measurable differences in the wind field. Thus, the QBO may be an amplifier of solar activity variations and a natural conduit of these variations to lower altitudes. To test this hypothesis, we conducted experiments with a 2D (two-dimensional) version of our Numerical Spectral Model that incorporates Hines' Doppler Spread Parameterization for small-scale gravity waves (GW). Solar cycle radiance variations (SCRV) are accounted for by changing the radiative heating rate on a logarithmic scale from 0.1 % at the surface to 1 % at 50 km to 10% at 100 km. With and without SCRV, but with the same GW flux, we then conduct numerical experiments to evaluate the magnitude of the SCAE in the zonal circulation. The numerical results indicate that, under certain conditions, the SCAE is significant and can extend to lower altitudes where the SCRV is inconsequential. At 20-km the differences in the modeled wind velocities are as large as 5 m/s. For a modeled QBO period of 30 months, we find that the seasonal cycle in the solar forcing (through the Semi-annual Oscillation (SAO)) acts as a strong pacemaker to lockup the

  13. Phase Relationships of Solar Hemispheric Toroidal and Poloidal Cycles

    NASA Astrophysics Data System (ADS)

    Muraközy, J.

    2016-08-01

    The solar northern and southern hemispheres exhibit differences in their intensities and time profiles of the activity cycles. The time variation of these properties was studied in a previous article covering the data from Cycles 12-23. The hemispheric phase lags exhibited a characteristic variation: the leading role was exchanged between hemispheres every four cycles. The present work extends the investigation of this variation using the data of Staudacher and Schwabe in Cycles 1-4 and 7-10 as well as Spörer’s data in Cycle 11. The previously observed variation cannot be clearly recognized using the data of Staudacher, Schwabe, and Spörer. However, it is more interesting that the phase lags of the reversals of the magnetic fields at the poles follow the same variations as those of the hemispheric cycles in Cycles 12-23, i.e., one of the hemispheres leads in four cyles and the leading role jumps to the opposite hemisphere in the next four cycles. This means that this variation is a long-term property of the entire solar dynamo mechanism, for both the toroidal and poloidal fields, which hints at an unidentified component of the process responsible for the long-term memory.

  14. 19th-century American contributions to the recording of tremors.

    PubMed

    Lanska, D J

    2000-07-01

    Studies of tremor in the 19th century were based initially on simple observation and later on the use of crude graphic recording devices that had been modified from instruments developed for other purposes. Like several European contemporaries, American investigators studying tremor used and adapted various existing instruments, including tambours and sphygmographs. A tambour used a drum-shaped pneumatic mechanism to transmit movements to a recording instrument, whereas the sphygmograph was a nonpneumatic mechanical device initially used to record the pulse. 19th-century American neurologists who used such devices included Frederick Peterson, Hobart Amory Hare, Charles Loomis Dana, and Augustus A. Eshner. Their measurements of tremor frequency were generally consistent with modern estimates for various types of tremor. Eshner, in particular, was frustrated by the overlap of frequency domains for tremors in different diseases, because this precluded use of tremor frequency alone as a differentiating feature for diagnosis. Peterson and Dana recognized the variation in tremor frequency in different body parts resulting from different natural resonance frequencies of these parts as a function of weight and elastic properties. Peterson, Dana, and Eshner also recognized that tremor amplitude and frequency are inversely related. Finally, these 19th-century investigators recognized that the tremor of Parkinson's disease is a relatively low-frequency rest tremor, suppressed by action, and generally synchronous in symmetric body parts, but varying in amplitude and frequency in different body parts or over time.

  15. Brutal and negligent? 19th century factory mothers and child care.

    PubMed

    Reynolds, Melanie

    2011-10-01

    This paper aims to highlight some working class women's childcare practices in northern industrial areas of Britain during the latter half of the 19th century. It aims to challenge the commonly held belief that 19th century northern working-class factory mothers were irresponsive and neglectful toward their infants, thereby fuelling the high northern infant mortality rate. It will do this by showing that factory mothers were responsible and responsive toward their infants despite being thwarted by the working patterns of industrialisation. It begins by outlining the arguments made by historians that northern working class women were neglectful toward their children. Then key areas such as the working patterns of waged factory mothers will be illustrated to show the agency and determination of 19th century working class women to provide their infants with good care. Reassessment of these historical childcare practices can provide a springboard by which today's health professionals can endeavour to maintain accurate and fair perspectives about the childcare practices of today's women of low socio-economic status.

  16. On the relationship between the Solar Cycle and the Secular Solar Cycle with the Quasi- quinquennial Periodicity of Sunspots

    NASA Astrophysics Data System (ADS)

    Velasco Herrera, Victor Manuel

    We have done a Wavelet Spectral Analysis of the daily, monthly and annual series of Sunspots; the obtained results show that the 5.5 years (quasi-quinquennial) periodicity is systematically present in the spectrum of the secular maxima of solar activity. Such periodicity is attenuated or disappears during the secular minima: e.g. the Maunder, Dalton and Modern minima. Since such a quasi-quinquennial frequency has been attenuated during the preceding cycles 22 and 23, therefore, we should expect that such a periodicity will be attenuated or disappear during cycle 24 as well as in cycles 25 and 26. Such a behavior will confirm that we are in the descending phase of the secular cycle toward its minima at the end of cycle 26. Data of Suns Spots by the end of Cycle 24 will allow us either, to confirm our results on the relation between the 5.5 years periodicity and the solar secular cycle, or conversely to assume that the secular cycle is shifted, or even our results are not of general validity but only for some cycles as those associated to the Maunder, Dalton, and Modern minima.

  17. Element Abundances in the Sun and Solar Wind Along the Solar Cycle

    NASA Astrophysics Data System (ADS)

    Landi, Enrico

    2015-04-01

    Element abundances are a critical parameter in almost every aspect of solar physics, from regulating the energy flow and the structure of the solar interior, to shaping the energy losses of the solar atmosphere, ruling the radiative output of the UV, EUV and X-rays solar radiation which impacts the Earth's upper atmosphere, and determining the composition of the solar wind.In this work we study the evolution of the element abundances in the solar corona and in the solar wind from 1996 to date using data from SoHO, Hinode, Ulysses and ACE satellites, in order to determine their variability along the solar cycle, and the relationship between solar abundance variations in the solar wind and in its source regions in the solar atmosphere. We study all the most abundant elements, with a special emphasis on Ne and O. We discuss our results in light of the source region of the solar wind, and of the radiative output of the solar corona.

  18. Solar High Temperature Water-Splitting Cycle with Quantum Boost

    SciTech Connect

    Taylor, Robin; Davenport, Roger; Talbot, Jan; Herz, Richard; Genders, David; Symons, Peter; Brown, Lloyd

    2014-04-25

    A sulfur family chemical cycle having ammonia as the working fluid and reagent was developed as a cost-effective and efficient hydrogen production technology based on a solar thermochemical water-splitting cycle. The sulfur ammonia (SA) cycle is a renewable and sustainable process that is unique in that it is an all-fluid cycle (i.e., with no solids handling). It uses a moderate temperature solar plant with the solar receiver operating at 800°C. All electricity needed is generated internally from recovered heat. The plant would operate continuously with low cost storage and it is a good potential solar thermochemical hydrogen production cycle for reaching the DOE cost goals. Two approaches were considered for the hydrogen production step of the SA cycle: (1) photocatalytic, and (2) electrolytic oxidation of ammonium sulfite to ammonium sulfate in aqueous solutions. Also, two sub-cycles were evaluated for the oxygen evolution side of the SA cycle: (1) zinc sulfate/zinc oxide, and (2) potassium sulfate/potassium pyrosulfate. The laboratory testing and optimization of all the process steps for each version of the SA cycle were proven in the laboratory or have been fully demonstrated by others, but further optimization is still possible and needed. The solar configuration evolved to a 50 MW(thermal) central receiver system with a North heliostat field, a cavity receiver, and NaCl molten salt storage to allow continuous operation. The H2A economic model was used to optimize and trade-off SA cycle configurations. Parametric studies of chemical plant performance have indicated process efficiencies of ~20%. Although the current process efficiency is technically acceptable, an increased efficiency is needed if the DOE cost targets are to be reached. There are two interrelated areas in which there is the potential for significant efficiency improvements: electrolysis cell voltage and excessive water vaporization. Methods to significantly reduce water evaporation are

  19. Solar and interplanetary signatures of declining of solar magnetic fields: Implications to the next solar cycle 25

    NASA Astrophysics Data System (ADS)

    Bisoi, Susanta Kumar; Janardhan, P.; Ananthakrishnan, S.; Tokumaru, M.; Fujiki, K.

    2015-08-01

    Our detailed study of solar surface magnetic fields at high-latitudes, using magnetic synoptic magnetograms of NSO/Kitt Peak observatory from 1975-2014, has shown a steady decline of the field strength since mid-1990's until mid-2014, i.e. the solar maximum of cycle 24. We also found that magnetic field strength at high-latitudes declines after each solar cycle maximum, and since cycle 24 is already past its peak implies that solar surface magnetic fields will be continuing to decline until solar minimum of cycle 24. In addition, interplanetary scintillation (IPS) measurements of solar wind micro-turbulence levels, from Solar and Terrestrial Environment Laboratory (STEL), Japan, have also shown a steady decline in sync with the declining surface fields. Even the heliospheric magnetic fields (HMF) at 1 AU have been declined much below the previously proposed floor level of HMF of ~4.6 nT. From study of a correlation between the high-latitude surface fields and the HMF at the last four solar minima we found a floor value of HMF of ~3.2 nT. Using the above correlation and the fact that the high-latitude surface fields is expected to decline until the minimum of cycle 24, we estimate the value of the HMF at the minimum of cycle 24 will be 3.8 ± 0.2 nT and the peak sunspot number for solar cycle 25 will be 56±12 suggesting a weak sunspot activity to be continued in cycle 25 too.

  20. Airglow Intensities and the Solar Cycle

    NASA Astrophysics Data System (ADS)

    Garstang, R. H.

    1997-05-01

    Some time ago we reported (Bull AAS 27,1213,1995) on an analysis of a series of measurements of night sky brightness published by Walker (1988). Those measures were made at San Benito Mountain in California over a period of about 12 years. We have made minor improvements to our analysis and present our final results. We took each observed brightness measurement, and subtracted from it in turn our estimated contributions of light pollution, zodiacal light and faint star background. Allowances were made for nightly extinction coefficients. The remainder is the contribution of the airglow to the sky brightness. The airglow intensities, which are integrals over the B and V photometric bands, show good correlations with the Ottawa 10.7 cm solar flux intensities. We are performing a similar analysis on night sky brightnesses measured at Kitt Peak by Pilachowski and colleagues (PASP 101,707,1989) to strengthen our deduced correlations.

  1. Oscillator models of the solar cycle and the Waldmeier effect

    NASA Astrophysics Data System (ADS)

    Nagy, M.; Petrovay, K.

    2013-11-01

    We study the behaviour of the van der Pol oscillator when either its damping parameter μ or its nonlinearity parameter ξ is subject to additive or multiplicative random noise. Assuming various power law exponents for the relation between the oscillating variable and the sunspot number, for each case we map the parameter plane defined by the amplitude and the correlation time of the perturbation and mark the parameter regime where the sunspot number displays solar-like behaviour. Solar-like behaviour is defined here as a good correlation between the rise rate and cycle amplitude and the lack of a good correlation between the decay rate and amplitude, together with significant ({⪆ 10} %) r.m.s. variation in cycle lengths and cycle amplitudes. It is found that perturbing μ alone the perturbed van der Pol oscillator does not show solar-like behaviour. When the perturbed variable is ξ, solar-like behaviour is displayed for perturbations with a correlation time of about 3-4 years and significant amplitude. Such studies may provide useful constraints on solar dynamo models and their parameters.

  2. Mir Cooperative Solar Array Project Accelerated Life Thermal Cycling Test

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Scheiman, David A.

    1996-01-01

    The Mir Cooperative Solar Array (MCSA) project was a joint U.S./Russian effort to build a photovoltaic (PV) solar array and deliver it to the Russian space station Mir. The MCSA will be used to increase the electrical power on Mir and provide PV array performance data in support of Phase 1 of the International Space Station. The MCSA was brought to Mir by space shuttle Atlantis in November 1995. This report describes an accelerated thermal life cycle test which was performed on two samples of the MCSA. In eight months time, two MCSA solar array 'mini' panel test articles were simultaneously put through 24,000 thermal cycles. There was no significant degradation in the structural integrity of the test articles and no electrical degradation, not including one cell damaged early and removed from consideration. The nature of the performance degradation caused by this one cell is briefly discussed. As a result of this test, changes were made to improve some aspects of the solar cell coupon-to-support frame interface on the flight unit. It was concluded from the results that the integration of the U.S. solar cell modules with the Russian support structure would be able to withstand at least 24,000 thermal cycles (4 years on-orbit). This was considered a successful development test.

  3. Testing solar forcing of pervasive Holocene climate cycles

    NASA Astrophysics Data System (ADS)

    Turney, Chris; Baillie, Mike; Clemens, Steve; Brown, David; Palmer, Jonathan; Pilcher, Jonathan; Reimer, Paula; Leuschner, Hanns Hubert

    2005-09-01

    The temporal and spatial extent of Holocene climate change is an area of considerable uncertainty, with solar forcing recently proposed to be the origin of cycles identified in the North Atlantic region. To address these issues we have developed an annually resolved record of changes in Irish bog tree populations over the last 7468 years which, together with radiocarbon-dated bog and lake-edge populations, extend the dataset back to 9000 yr ago. The Irish trees underpin the internationally accepted radiocarbon calibration curve, used to derive a proxy of solar activity, and allow us to test solar forcing of Holocene climate change. Tree populations and age structures provide unambiguous evidence of major shifts in Holocene surface moisture, with a dominant cyclicity of 800 yr, similar to marine cycles in the North Atlantic, indicating significant changes in the latitude and intensity of zonal atmospheric circulation across the region. The cycles, however, are not coherent with changes in solar activity (both being on the same absolute timescale), indicating that Holocene North Atlantic climate variability at the millennial and centennial scale is not driven by a linear response to changes in solar activity. Copyright

  4. The Earth's climate at minima of Centennial Gleissberg Cycles

    NASA Astrophysics Data System (ADS)

    Ruzmaikin, Alexander; Feynman, Joan

    2015-10-01

    The recent extended, deep minimum of solar variability and the extended minima in the 19th and 20th centuries (1810-1830 and 1900-1920) are consistent with minima of the Centennial Gleissberg Cycle (CGC), a 90-100 year variation of the amplitude of the 11-year sunspot cycle observed on the Sun and at the Earth. The Earth's climate response to these prolonged low solar radiation inputs involves heat transfer to the deep ocean causing a time lag longer than a decade. The spatial pattern of the climate response, which allows distinguishing the CGC forcing from other climate forcings, is dominated by the Pacific North American pattern (PNA). The CGC minima, sometimes coincidently in combination with volcanic forcing, are associated with severe weather extremes. Thus the 19th century CGC minimum, coexisted with volcanic eruptions, led to especially cold conditions in United States, Canada and Western Europe.

  5. High solar cycle spectral variations inconsistent with stratospheric ozone observations

    NASA Astrophysics Data System (ADS)

    Ball, W. T.; Haigh, J. D.; Rozanov, E. V.; Kuchar, A.; Sukhodolov, T.; Tummon, F.; Shapiro, A. V.; Schmutz, W.

    2016-03-01

    Solar variability can influence surface climate, for example by affecting the mid-to-high-latitude surface pressure gradient associated with the North Atlantic Oscillation. One key mechanism behind such an influence is the absorption of solar ultraviolet (UV) radiation by ozone in the tropical stratosphere, a process that modifies temperature and wind patterns and hence wave propagation and atmospheric circulation. The amplitude of UV variability is uncertain, yet it directly affects the magnitude of the climate response: observations from the SOlar Radiation and Climate Experiment (SORCE) satellite show broadband changes up to three times larger than previous measurements. Here we present estimates of the stratospheric ozone variability during the solar cycle. Specifically, we estimate the photolytic response of stratospheric ozone to changes in spectral solar irradiance by calculating the difference between a reference chemistry-climate model simulation of ozone variability driven only by transport (with no changes in solar irradiance) and observations of ozone concentrations. Subtracting the reference from simulations with time-varying irradiance, we can evaluate different data sets of measured and modelled spectral irradiance. We find that at altitudes above pressure levels of 5 hPa, the ozone response to solar variability simulated using the SORCE spectral solar irradiance data are inconsistent with the observations.

  6. Thermal stress cycling of GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Francis, Robert W.

    1987-01-01

    Thermal stress cycling was performed on gallium arsenide solar cells to investigate their electrical, mechanical, and structural integrity. Cells were cycled under low Earth orbit (LEO) simulated temperature conditions in vacuum. Cell evaluations consisted of power output values, spectral response, optical microscopy and ion microprobe mass analysis, and depth profiles on both front surface inter-grid areas and metallization contact grid lines. Cells were examined for degradation after 500, 5,000, 10,000 and 15,245 thermal cycles. No indication of performance degradation was found for any vendor's cell lot.

  7. Background solar velocity spectrum at high and low phases of solar activity cycle

    NASA Astrophysics Data System (ADS)

    Régulo, C.; Roca Cortés, T.; Vázquez Ramió, H.

    2002-12-01

    Using GOLF/SOHO data a detailed analysis of the solar background spectrum has been performed at high and low phases of solar activity cycle. The analysis includes not only the non-periodic components of the background power spectrum but also the periodic ones. Apart from the solar activity, other causes produce similar effects in the data, particularly the different depths in the solar atmosphere where the measurements are done, because due to the sun-satellite relative velocity, we are observing at different positions in the line profile. Another effect is that different line wings are used in the observation at two different epochs, before and after SOHO loss and recovery which, unfortunately, coincide with minimum and maximum of solar activity. In this work we have tried to separate all these effects in order to really understand what is being seen in the data and ultimately extract the effects of solar activity on the acoustic background solar spectrum.

  8. Variations in the Sun's Meridional Flow Over a Solar Cycle

    NASA Technical Reports Server (NTRS)

    Hathaway, David H.; Rightmire, Lisa

    2010-01-01

    The Sun's meridional flow is an axisymmetric flow that is generally directed from its equator toward its poles at the surface. The structure and strength of the meridional flow determine both the strength of the Sun's polar magnetic field and the intensity of sunspot cycles. We determine the meridional flow speed of magnetic features on the Sun using data from the Solar and Heliospheric Observatory. The average flow is poleward at all latitudes up to 75 , which suggests that it extends to the poles. It was faster at sun spot cycle minimum than at maximum and substantially faster on the approach to the current minimum than it was at the last solar minimum. This result may help to ex plain why this solar activity minimum is so peculiar.

  9. OH Column Abundance Apparent Response to Solar Cycle 23

    NASA Astrophysics Data System (ADS)

    Burnett, C. R.; Minschwaner, K. R.

    2009-12-01

    The 33-year series of high spectral resolution measurements of absorption of sunlight by OH at 308 nm has exhibited temporary decreases of column abundances in 1986, 1997, and 2008 near the times of minimum solar activity. These observations and analyses are of significance as they encompass three complete solar cycles for comparison. During solar cycle 23, the annual average abundances increased approximately 20% from the minimum abundance in 1997 to high-sun enhanced values in 2000-2006, then dropped approximately 15% in 2008. The abundances exhibited a pronounced reduction at solar minimum in August-October 2008, similar to that seen in fall 1986 and fall 1997. The average morning abundances on those occasions were 13% smaller than the 1980-88 corresponding average, about 0.9 x 1013 cm-2, with minimum values broadly consistent with model results. In contrast, high-sun OH abundances observed during periods of solar maximum are approximately 33% larger than modeled abundances. This discrepancy cannot be explained by reasonable adjustments of reaction rates or modeled constituent concentrations in the stratosphere or mesosphere. However, the observed responses to a tropopause fold event in 1988 and to the Pinatubo aerosol in 1991 do suggest an important contribution to the total OH column from the lower stratosphere. In addition to the apparent variations with solar activity, this OH column database contains a number of other effects such as diurnal and seasonal patterns, and geographic differences between observations from Colorado, Florida, Alaska, Micronesia, New Zealand, and New Mexico.

  10. Improvement of Space Weather Forecasting in Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Nitta, N.

    2014-12-01

    Solar Cycle 24 has not produced extreme space weather events at Earthcomparable to the Halloween 2003 events. However, there have been anumber of geomagnetic storms more intense than Dst of 100 nT as wellas several major solar energetic particle (SEP) events at Earth.Before predicting geomagnetic storms and radiation storms well inadvance, it is necessary to make a firm link of solar activity,notably coronal mass ejections (CMEs), with interplanetary CMEs(ICMEs) and shock waves. This cycle has benefitted from the SolarDynamics Observatory that provides uninterrupted and high-qualityfull-disk images at Earth, and the Solar Terrestrial RelationsObservatory that has observed CMEs away from the Sun-Earth line andunambiguously isolated those that were directed toward Earth. Thispresentation aims at evaluating how these observations have refinedour understanding of the origins of ICMEs and helped models reproducethe arrival times of the disturbances and the occurrence and magnitudeof SEP events. We also discuss what may be critically missing and yetessential for achieving useful predictions in the future. A review isgiven as to how the forecasts on the basis of solar and near-Sunobservations have fared against the actual ICMEs and shocks, and howmany of the latter have not been properly handled because of noobvious CMEs. A similar attempt is made for the occurrence andmagnitude of SEP events. It is important to critically analyze theinadequate forecasts (or just expectations) in terms of uncertaintiesfrom observations and modeling.

  11. Solar Sources of 3He-rich Solar Energetic Particle Events in Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Nitta, Nariaki V.; Mason, Glenn M.; Wang, Linghua; Cohen, Christina; Wiedenbeck, Mark E.

    2015-04-01

    We still do not understand the origin of impulsive SEP events enriched in 3He and heavy ions. A major impediment may be the difficulty to observe them in the corona, apart from the common knowledge that 3He-rich SEP events are correlated with longer-than-metric type III radio bursts and <100 keV electron events. This is because their X-ray and EUV signatures tend to be tiny and short-lived. Using high-cadence and high-sensitivity EUV images obtained by SDO/AIA, we investigate the solar sources of 26 3He-rich SEP events during solar cycle 24 that were well-observed by ACE. The source locations are further confirmed in data from STEREO/EUVI, which capture solar activities in the regions inaccessible from the Earth. We confirm that 3He-rich events have a broad longitudinal distribution (including locations well behind the west limb) and that a frequent association with coronal jets and narrow CMEs. Some events were seen in association with eruptions of closed structures and large-scale coronal propagating fronts (LCPFs, aka EUV waves). While these LCPFs may account for the occasional mismatching polarities at the source region and L1 in such a way that the particles are transported to and released at a region that has the opposite polarity, their associated CMEs may not be fast enough to drive shock waves for particle acceleration. Moreover, open field lines from PFSS models may not be correct for the entire Sun although they often look reasonable in discrete locations. We also discuss the apparent lack of correlation between the solar sources and the basic properties of 3He-rich SEP events.

  12. SOLAR MAGNETIC HELICITY INJECTED INTO THE HELIOSPHERE: MAGNITUDE, BALANCE, AND PERIODICITIES OVER SOLAR CYCLE 23

    SciTech Connect

    Georgoulis, M. K.; Rust, D. M.; Bernasconi, P. N.; Pevtsov, A. A.; Kuzanyan, K. M.

    2009-11-01

    Relying purely on solar photospheric magnetic field measurements that cover most of solar cycle 23 (1996-2005), we calculate the total relative magnetic helicity injected into the solar atmosphere, and eventually shed into the heliosphere, over the latest cycle. Large active regions dominate the helicity injection process with approx5.7 x 10{sup 45} Mx{sup 2} of total injected helicity. The net helicity injected is approx<1% of the above output. Peculiar active-region plasma flows account for approx80% of this helicity; the remaining approx20% is due to solar differential rotation. The typical helicity per active-region CME ranges between (1.8-7) x 10{sup 42} Mx{sup 2} depending on the CME velocity. Accounting for various minor underestimation factors, we estimate a maximum helicity injection of approx6.6 x 10{sup 45} Mx{sup 2} for solar cycle 23. Although no significant net helicity exists over both solar hemispheres, we recover the well-known hemispheric helicity preference, which is significantly enhanced by the solar differential rotation. We also find that helicity injection in the solar atmosphere is an inherently disorganized, impulsive, and aperiodic process.

  13. Solar powered Stirling cycle electrical generator

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.

    1991-01-01

    Under NASA's Civil Space Technology Initiative (CSTI), the NASA Lewis Research Center is developing the technology needed for free-piston Stirling engines as a candidate power source for space systems in the late 1990's and into the next century. Space power requirements include high efficiency, very long life, high reliability, and low vibration. Furthermore, system weight and operating temperature are important. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, non-contacting gas bearings, and can be hermetically sealed. These attributes of the free-piston Stirling engine also make it a viable candidate for terrestrial applications. In cooperation with the Department of Energy, system designs are currently being completed that feature the free-piston Stirling engine for terrestrial applications. Industry teams were assembled and are currently completing designs for two Advanced Stirling Conversion Systems utilizing technology being developed under the NASA CSTI Program. These systems, when coupled with a parabolic mirror to collect the solar energy, are capable of producing about 25 kW of electricity to a utility grid. Industry has identified a niche market for dish Stirling systems for worldwide remote power application. They believe that these niche markets may play a major role in the introduction of Stirling products into the commercial market.

  14. On the Relationship Between Solar Wind Speed, Geomagnetic Activity, and the Solar Cycle Using Annual Values

    NASA Technical Reports Server (NTRS)

    Wilson, Robert M.; Hathaway, David H.

    2008-01-01

    The aa index can be decomposed into two separate components: the leading sporadic component due to solar activity as measured by sunspot number and the residual or recurrent component due to interplanetary disturbances, such as coronal holes. For the interval 1964-2006, a highly statistically important correlation (r = 0.749) is found between annual averages of the aa index and the solar wind speed (especially between the residual component of aa and the solar wind speed, r = 0.865). Because cyclic averages of aa (and the residual component) have trended upward during cycles 11-23, cyclic averages of solar wind speed are inferred to have also trended upward.

  15. Solar energetic particle characteristics and their dependence on longitude in solar cycle 24

    NASA Astrophysics Data System (ADS)

    Cohen, C. M. S.; Mason, G. M.; Mewaldt, R. A.; von Rosenvinge, T. T.

    2013-06-01

    In previous solar cycles, most studies examining the longitude dependence of solar energetic particle (SEP) event characteristics (such as composition and spectral hardness) have involved statistical analysis of single-point measurements. With the significant separation between the two STEREO and near-Earth spacecraft during solar cycle 24, these SEP characteristics can be examined simultaneously from multiple vantage points. Using SEP measurements from sensors on STEREO and ACE, we have examined the longitude dependence of the Fe/O abundance ratio at 10 MeV/nuc and the oxygen spectral index for energies above 10 MeV/nuc. Longitudinal patterns were sought that support or refute the scenarios put forth by Tylka et al. and Cane et al. to explain the Fe-enriched large SEP events of cycle 23. Unfortunately few Fe-enriched events have occurred in cycle 24 and their longitudinal behavior is not entirely consistent with either of the proposed scenarios.

  16. Effects of Low Activity Solar Cycle on Orbital Debris Lifetime

    NASA Technical Reports Server (NTRS)

    Cable, Samual B.; Sutton, Eric K.; Lin, chin S.; Liou, J.-C.

    2011-01-01

    Long duration of low solar activity in the last solar minimum has an undesirable consequence of extending the lifetime of orbital debris. The AFRL TacSat-2 satellite decommissioned in 2008 has finally re-entered into the atmosphere on February 5th after more than one year overdue. Concerning its demise we have monitored its orbital decay and monthly forecasted Tacsat-2 re-entry since September 2010 by using the Orbital Element Prediction (OEP) model developed by the AFRL Orbital Drag Environment program. The model combines estimates of future solar activity with neutral density models, drag coefficient models, and an orbit propagator to predict satellite lifetime. We run the OEP model with solar indices forecast by the NASA Marshall Solar Activity Future Estimation model, and neutral density forecast by the MSIS-00 neutral density model. Based on the two line elements in 2010 up to mid September, we estimated at a 50% confidence level TacSat-2's re-entry time to be in early February 2011, which turned out to be in good agreement with Tacsat-2's actual re-entry date. The potential space weather effects of the coming low activity solar cycle on satellite lifetime and orbital debris population are examined. The NASA long-term orbital debris evolutionary model, LEGEND, is used to quantify the effects of solar flux on the orbital debris population in the 200-600 km altitude environment. The results are discussed for developing satellite orbital drag application product.

  17. Solar panel thermal cycling testing by solar simulation and infrared radiation methods

    NASA Technical Reports Server (NTRS)

    Nuss, H. E.

    1980-01-01

    For the solar panels of the European Space Agency (ESA) satellites OTS/MAROTS and ECS/MARECS the thermal cycling tests were performed by using solar simulation methods. The performance data of two different solar simulators used and the thermal test results are described. The solar simulation thermal cycling tests for the ECS/MARECS solar panels were carried out with the aid of a rotatable multipanel test rig by which simultaneous testing of three solar panels was possible. As an alternative thermal test method, the capability of an infrared radiation method was studied and infrared simulation tests for the ultralight panel and the INTELSAT 5 solar panels were performed. The setup and the characteristics of the infrared radiation unit using a quartz lamp array of approx. 15 sq and LN2-cooled shutter and the thermal test results are presented. The irradiation uniformity, the solar panel temperature distribution, temperature changing rates for both test methods are compared. Results indicate the infrared simulation is an effective solar panel thermal testing method.

  18. Longitudinal Waves Drive the Solar Cycle

    NASA Astrophysics Data System (ADS)

    Wagner, Orvin

    2000-05-01

    In Physics Essays 12: 3-10 I explain the placement of the planets in terms of low velocity waves emitted by the sun. Evidence for the wave pulse generated near the center of the sun is indicated by the initial high latitude sunspots observed on the butterfly diagram. The wave pulse carries charge with it as observed for similar waves in plants (W-waves). For the first half cycle negative charge is carried to the surface of the sun where much of the wave pulse radiates a wave crest into space while the charge slowly redistributes itself. Meanwhile the next wave pulse carrying excess positive charge moves outward. Rotating charge determines the polarity of the sun's magnetic poles so they reverse as the pulse moves outward. The wave pulse, which interacts strongly with force fields, is guided by centripetal force and gravity so that the pulse comes out near the sun's equator. W-waves produce an automatic return wave in the vacuum so that standing waves are produced in the space around the sun providing a template for the formation and stabilization planets. W-waves are hypothesized to provide self organization for both the universe and life. See the

  19. Nonlinear data assimilation: towards a prediction of the solar cycle

    NASA Astrophysics Data System (ADS)

    Svedin, Andreas

    The solar cycle is the cyclic variation of solar activity, with a span of 9-14 years. The prediction of the solar cycle is an important and unsolved problem with implications for communications, aviation and other aspects of our high-tech society. Our interest is model-based prediction, and we present a self-consistent procedure for parameter estimation and model state estimation, even when only one of several model variables can be observed. Data assimilation is the art of comparing, combining and transferring observed data into a mathematical model or computer simulation. We use the 3DVAR methodology, based on the notion of least squares, to present an implementation of a traditional data assimilation. Using the Shadowing Filter — a recently developed method for nonlinear data assimilation — we outline a path towards model based prediction of the solar cycle. To achieve this end we solve a number of methodological challenges related to unobserved variables. We also provide a new framework for interpretation that can guide future predictions of the Sun and other astrophysical objects.

  20. Is a Dynamo Process Essential for Explaining the Solar Cycle?

    NASA Astrophysics Data System (ADS)

    Sturrock, P. A.

    1996-05-01

    The magnetic field at the solar photosphere is highly structured and time-variable, suggesting that it is generated and regenerated by a dynamo process that occurs within or at the base of the convection zone. However, it is proving difficult to explain all the properties of the solar cycle, and to match the rotational velocity profiles obtained by means of helioseismological observations, within the context of a dynamo model. Furthermore, there is some evidence that the neutrino flux is time varying, and that the variation is correlated with the solar cycle. This fact, if it proves to be correct, would be difficult to understand on the basis of a dynamo model, unless the neutrino has a magnetic moment, which would require that the neutrino has a non-zero mass. For these and other reasons, it is perhaps prudent to question the assumption that dynamo action is essential for explaining the solar cycle. One way to seek to determine whether dynamo action is essential is to look for an alternative. If the neutrino flux is time variable, this may indicate that nuclear burning is not steady, in which case it is likely that it is not spherically symmetric either. Nuclear burning that is neither steady nor spherically symmetric must be expected to lead to hydrodynamic flows within the Sun. It will be argued that a certain flow pattern, and a certain associated magnetic field pattern, can readily reproduce some of the salient properties of the solar cycle. This work was supported in part by Air Force grant F49620-95-1-008 and NASA grant NAGW-2265.

  1. Thermal Cycling of Mir Cooperative Solar Array (MCSA) Test Panels

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.; Scheiman, David A.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA) project was a joint US/Russian effort to build a photovoltaic (PV) solar array and deliver it to the Russian space station Mir. The MCSA is currently being used to increase the electrical power on Mir and provide PV array performance data in support of Phase 1 of the International Space Station (ISS), which will use arrays based on the same solar cells used in the MCSA. The US supplied the photovoltaic power modules (PPMs) and provided technical and programmatic oversight while Russia provided the array support structures and deployment mechanism and built and tested the array. In order to ensure that there would be no problems with the interface between US and Russian hardware, an accelerated thermal life cycle test was performed at NASA Lewis Research Center on two representative samples of the MCSA. Over an eight-month period (August 1994 - March 1995), two 15-cell MCSA solar array 'mini' panel test articles were simultaneously put through 24,000 thermal cycles (+80 C to -100 C), equivalent to four years on-orbit. The test objectives, facility, procedure and results are described in this paper. Post-test inspection and evaluation revealed no significant degradation in the structural integrity of the test articles and no electrical degradation, not including one cell damaged early as an artifact of the test and removed from consideration. The interesting nature of the performance degradation caused by this one cell, which only occurred at elevated temperatures, is discussed. As a result of this test, changes were made to improve some aspects of the solar cell coupon-to-support frame interface on the flight unit. It was concluded from the results that the integration of the US solar cell modules with the Russian support structure would be able to withstand at least 24,000 thermal cycles (4 years on-orbit).

  2. Study on solar energetic particles in the rising half of solar cycle 24

    NASA Astrophysics Data System (ADS)

    Miteva, Rositsa; Samwel, Susan

    We present a list of 45 solar energetic particle (SEP) events in solar cycle 24 (2007-2013) following the preliminary listing by NOAA GOES and SEPServer SOHO/ERNE. We identified the onset time and peak intensity for the protons from Wind/EPACT and electrons from ACE/EPAM data. We propose flare/coronal mass ejection (CME) identification for each SEP event. We note a slightly higher percentage of eastern events (36 percent) in the first half of the present solar cycle compared to the entire previous one (27 percent). We completed a correlation study between the particle intensities and the flare GOES class and CME projected speed from SOHO/LASCO-C2 catalog. We found a lower correlation between the eastern SEPs peak intensities and the flare class, compared to the CME speed, although the difference is not statistically significant. Finally, we comment on the differences between SEP events and parent solar activity in the solar cycle 23 and rising part of solar cycle 24.

  3. The solar wind - Advances in our knowledge through two solar cycles

    NASA Technical Reports Server (NTRS)

    Feynman, Joan

    1989-01-01

    As the Pioneer and Voyager spacecraft have moved outward they have gradually unfolded a view of distant regions of the heliosphere. Information on the solar wind velocity, density and temperature as a function of distance out to more than 40 AU has been gathered. Meanwhile the description of the solar wind has evolved. Long-standing questions on the sources of the wind causing geomagnetic activity were clarified by the discovery of coronal holes and coronal mass ejections. The propagation of the resultant solar wind disturbances through the heliosphere has been studied using both observations and models. Plasma physical processes have been studied. This review focuses on the development of the concepts that have been used to describe the solar wind in the three dimensional heliosphere over the last two solar cycles. Collisionless shocks, transient disturbances in space, disturbance propagation and the distant solar wind are discussed.

  4. Solar cycle variations in the powers and damping rates of low-degree solar acoustic oscillations

    NASA Astrophysics Data System (ADS)

    Broomhall, A.-M.; Pugh, C. E.; Nakariakov, V. M.

    2015-12-01

    Helioseismology uses the Sun's natural resonant oscillations to study the solar interior. The properties of the solar oscillations are sensitive to the Sun'2019;s magnetic activity cycle. Here we examine variations in the powers, damping rates, and energy supply rates of the most prominent acoustic oscillations in unresolved, Sun-as-a-star data, obtained by the Birmingham Solar Oscillations Network (BiSON) during solar cycles 22, 23, and the first half of 24. The variations in the helioseismic parameters are compared to the 10.7 cm flux, a well-known global proxy of solar activity. As expected the oscillations are most heavily damped and the mode powers are at a minimum at solar activity maximum. The 10.7 cm flux was linearly regressed using the fractional variations of damping rates and powers observed during cycle 23. In general, good agreement is found between the damping rates and the 10.7 cm flux. However, the linearly regressed 10.7 cm flux and fractional variation in powers diverge in cycles 22 and 24, indicating that the relationship between the mode powers and the 10.7 cm flux is not consistent from one cycle to the next. The energy supply rate of the oscillations, which is usually approximately constant, also decreases at this time. We have determined that this discrepancy is not because of the first-order bias introduced by an increase in the level of background noise or gaps in the data. Although we cannot categorically rule out an instrumental origin, the divergence observed in cycle 24, when the data were of high quality and the data coverage was over 80%, raises the possibility that the effect may be solar in origin.

  5. Solar cycle, QBO effect to the stratosphere and troposphere

    NASA Astrophysics Data System (ADS)

    Yamashita, Y.; Sakamoto, K.; Akiyoshi, H.; Zhou, L. B.; Nagashima, T.; Takahashi, M.

    2007-05-01

    The energy flux of high energy UV radiation changes by large amounts (>5%) during the 11-year solar cycle (Kuroda and Kodera, 2002). Ozone concentration variation in the tropical lower stratosphere is effected by the 11- year solar cycle, which is also influenced by the Quasi-biennial Oscillation (QBO), volcanic eruptions. In contrast, the temperature in the polar region is modulated by the 11-year solar cycle and the QBO (Labitzke, 1987). Labitzke and van Loon (1988) shows horizontal structure of the temperature anomaly, which indicates north-south dipole structure between the north pole and mid latitude. This structure is similar to the Arctic Oscillation (AO) or the Northern Hemisphere annular mode (NAM). The Chemistry and Climate Model (CCM) runs are performed with the REF1 scenario of Chemistry -Climate Model Validation (CCMVal, Eyring et al., 2006). The model includes the effects of the 11-year solar variation, QBO, and volcanic eruptions. We also use National Centers for Environmental Prediction (NCEP) / National Center for Atmospheric Research (NCAR) reanalysis data library. The latitude-height section of the ozone mixing ratio associated with the solar cycle shows small value around equatorial 30 hPa. On the other hand, there is large around equatorial 50 hPa. Our analyses find that the large value around 10-5hPa is caused mostly by the ozone production of the oxygen photolysis, while the small and large values in 30 and 50hPa are caused by dynamical responses of the vertical ozone advection. We derive two indices of the AO/NAM over the northern mid and high latitude stratosphere and the troposphere, and correlation analysis of the indices is applied to the four groups which are classified according to the phase of the solar cycle and the QBO. In the early winter (ND), the zonal wind shows westerly anomaly centered at 60 ° N from the stratosphere to the troposphere for the westward phase of the QBO with the solar maximum. This structure is maintained by

  6. [Epidemic Cholera and American Reform Movements in the 19th Century].

    PubMed

    Kim, Seohyung

    2015-12-01

    The 19th century was the age of great reform in American history. After constructing of the canal and railroads, the industrialization began and American society changed so rapidly. In this period, there were so many social crisis and American people tried to solve these problems within the several reform movements. These reform movements were the driving forces to control cholera during the 19th century. Cholera was the endemic disease in Bengal, India, but after the 19th century it had spread globally by the development of trade networks. The 1832 cholera in the United States was the first epidemic cholera in American history. The mortality of cholera was so high, but it was very hard to find out the cause of this fatal infectious disease. So, different social discourses happened to control epidemic cholera in the 19th century, these can be understood within the similar context of American reform movements during this period. Board of Health in New York States made a new public health act to control cholera in 1832, it was ineffective. Some people insisted that the cause of this infectious disease was the corruption of the United States. They emphasized unjust and immoral system in American society. Moral reform expanded to Nativism, because lots of Irish immigrants were the victims of cholera. So, epidemic cholera was the opportunity to spread the desire for moral reform. To control cholera in 1849, the sanitary reform in Britain had affected. The fact that it was so important to improve and maintain the water quality for the control and prevention of disease spread, the sanitary reform happened. There were two different sphere of the sanitary reform. The former was the private reform to improve sewer or privy, the latter was the public reform to build sewage facilities. The 1849 cholera had an important meaning, because the social discourse, which had emphasized the sanitation of people or home expanded to the public sphere. When cholera broke out in 1866 again

  7. [Epidemic Cholera and American Reform Movements in the 19th Century].

    PubMed

    Kim, Seohyung

    2015-12-01

    The 19th century was the age of great reform in American history. After constructing of the canal and railroads, the industrialization began and American society changed so rapidly. In this period, there were so many social crisis and American people tried to solve these problems within the several reform movements. These reform movements were the driving forces to control cholera during the 19th century. Cholera was the endemic disease in Bengal, India, but after the 19th century it had spread globally by the development of trade networks. The 1832 cholera in the United States was the first epidemic cholera in American history. The mortality of cholera was so high, but it was very hard to find out the cause of this fatal infectious disease. So, different social discourses happened to control epidemic cholera in the 19th century, these can be understood within the similar context of American reform movements during this period. Board of Health in New York States made a new public health act to control cholera in 1832, it was ineffective. Some people insisted that the cause of this infectious disease was the corruption of the United States. They emphasized unjust and immoral system in American society. Moral reform expanded to Nativism, because lots of Irish immigrants were the victims of cholera. So, epidemic cholera was the opportunity to spread the desire for moral reform. To control cholera in 1849, the sanitary reform in Britain had affected. The fact that it was so important to improve and maintain the water quality for the control and prevention of disease spread, the sanitary reform happened. There were two different sphere of the sanitary reform. The former was the private reform to improve sewer or privy, the latter was the public reform to build sewage facilities. The 1849 cholera had an important meaning, because the social discourse, which had emphasized the sanitation of people or home expanded to the public sphere. When cholera broke out in 1866 again

  8. SPE in Solar Cycle 24 : Flare and CME characteristic

    NASA Astrophysics Data System (ADS)

    Neflia, Neflia

    SPE is one of the most severe hazards in the space environment. Such events, tend to occur during periods of intense solar activity, and can lead to high radiation doses in short time intervals. The proton enhancements produced by these solar events may last several days and are very hard to predict in advance and they also can cause harm to both satellite and human in space. The most significant sources of proton in the interplanetary medium are both solar flares and interplanetary shocks driven by coronal mass ejections (CMEs). In this study, I try to find the characteristic of Flare and CME that can cause the proton events in interplanetary medium. For my preliminary study, I will search flare characteristic such as class and position as an SPE causes. I also did the research with CME characteristic such as Angular Width (AW) and linier velocity. During solar cycle 24, the solar activity remain very low with several large flare and Halo CME. This low activity also occur on solar proton events in interplanetary medium. From January 2009 to May 2013, there are 25 SPEs with flux range from 12 - 6530 sfu (10 MeV). The solar flare during these events varies from C to X- class flare. From 27 X-class flare that occur during 2009 - May 2013, only 7 flares cause the SPE. Most of active region location are at solar Western Hemisphere (16/25). only 24 from 139 halo CME (AW=360) cause SPE. Although the probability of SPE from all flare and CME during this range of time is small but they have 3 common characteristics, ie, most of the SPE have active region position at Solar Western Hemisphere, the CME have AW=360 and they have a high linier velocity.

  9. A Possible Cause of the Diminished Solar Wind During the Solar Cycle 23 - 24 Minimum

    NASA Astrophysics Data System (ADS)

    Liou, Kan; Wu, Chin-Chun

    2016-10-01

    Interplanetary magnetic field and solar wind plasma density observed at 1 AU during Solar Cycle 23 - 24 (SC-23/24) minimum were significantly smaller than those during its previous solar cycle (SC-22/23) minimum. Because the Earth's orbit is embedded in the slow wind during solar minimum, changes in the geometry and/or content of the slow wind region (SWR) can have a direct influence on the solar wind parameters near the Earth. In this study, we analyze solar wind plasma and magnetic field data of hourly values acquired by Ulysses. It is found that the solar wind, when averaging over the first (1995.6 - 1995.8) and third (2006.9 - 2008.2) Ulysses' perihelion (˜ 1.4 AU) crossings, was about the same speed, but significantly less dense ( {˜} 34 %) and cooler ( {˜} 20 %), and the total magnetic field was {˜} 30 % weaker during the third compared to the first crossing. It is also found that the SWR was {˜} 50 % wider in the third ( {˜} 68.5° in heliographic latitude) than in the first ( {˜} 44.8° solar orbit. The observed latitudinal increase in the SWR is sufficient to explain the excessive decline in the near-Earth solar wind density during the recent solar minimum without speculating that the total solar output may have been decreasing. The observed SWR inflation is also consistent with a cooler solar wind in the SC-23/24 than in the SC-22/23 minimum. Furthermore, the ratio of the high-to-low latitude photospheric magnetic field (or equatorward magnetic pressure force), as observed by the Mountain Wilson Observatory, is smaller during the third than the first Ulysses' perihelion orbit. These findings suggest that the smaller equatorward magnetic pressure at the Sun may have led to the latitudinally-wider SRW observed by Ulysses in SC-23/24 minimum.

  10. Statistical properties of solar flares and coronal mass ejections through the solar cycle

    NASA Astrophysics Data System (ADS)

    Telloni, Daniele; Carbone, Vincenzo; Lepreti, Fabio; Antonucci, Ester

    2016-03-01

    Waiting Time Distributions (WTDs) of solar flares are investigated all through the solar cycle. The same approach applied to Coronal Mass Ejections (CMEs) in a previous work is considered here for flare occurrence. Our analysis reveals that flares and CMEs share some common statistical properties, which result dependent on the level of solar activity. Both flares and CMEs seem to independently occur during minimum solar activity phases, whilst their WTDs significantly deviate from a Poisson function at solar maximum, thus suggesting that these events are correlated. The characteristics of WTDs are constrained by the physical processes generating those eruptions associated with flares and CMEs. A scenario may be drawn in which different mechanisms are actively at work during different phases of the solar cycle. Stochastic processes, most likely related to random magnetic reconnections of the field lines, seem to play a key role during solar minimum periods. On the other hand, persistent processes, like sympathetic eruptions associated to the variability of the photospheric magnetism, are suggested to dominate during periods of high solar activity. Moreover, despite the similar statistical properties shown by flares and CMEs, as it was mentioned above, their WTDs appear different in some aspects. During solar minimum periods, the flare occurrence randomness seems to be more evident than for CMEs. Those persistent mechanisms generating interdependent events during maximum periods of solar activity can be suggested to play a more important role for CMEs than for flares, thus mitigating the competitive action of the random processes, which seem instead strong enough to weaken the correlations among flare event occurrence during solar minimum periods. However, it cannot be excluded that the physical processes at the basis of the origin of the temporal correlation between solar events are different for flares and CMEs, or that, more likely, more sophisticated effects are

  11. Solar Cycle Variation and Multipoint Studies of ICME Properties

    NASA Technical Reports Server (NTRS)

    Russell, C. T.

    2005-01-01

    The goal of the Living With a Star program is to understand the Sun-Earth connection sufficiently well that we can solve problems critical to life and society. This can most effectively be done in the short term using observations from our past and on-going programs. Not only can this approach solve some of the pressing issues but also it can provide ideas for the deployment of future spacecraft in the LWS program. The proposed effort uses data from NEAR, SOHO, Wind, ACE and Pioneer Venus in quadrature, multipoint, and solar cycle studies to study the interplanetary coronal mass ejection and its role in the magnetic flux cycle of the Sun. ICMEs are most important to the LWS objectives because the solar wind conditions associated with these structures are the most geoeffective of any solar wind phenomena. Their ability to produce strong geomagnetic disturbances arises first because of their high speed. This high speed overtakes the ambient solar wind producing a bow shock wave similar to the terrestrial bow shock. In the new techniques we develop as part of this effort we exploit this feature of ICMEs. This shocked plasma has a greater velocity, higher density and stronger magnetic field than the ambient solar wind, conditions that can enhance geomagnetic activity. The driving ICME is a large magnetic structure expanding outward in the solar wind [Gosling, 19961. The ICMEs magnetic field is generally much higher than that in the ambient solar wind and the velocity is high. The twisted nature of the magnetic field in an ICME almost ensures that sometime during the ICME conditions favorable for geomagnetic storm initiation will occur.

  12. Glacier changes on South Georgia since the late-19th century documented in historical photographs

    NASA Astrophysics Data System (ADS)

    Gordon, John; Haynes, Valerie

    2014-05-01

    South Georgia is one of the few landmasses in the Southern Ocean. It provides a crucial geographical datapoint for glacier responses to climate change over different timescales. As part of an ongoing glacier inventory of the island, we are compiling a database of historical glacier photographs. Since the late 19th century, the island has been visited by numerous scientific and survey expeditions, as well as being the land-base for a major whaling industry. Historical photographs of the island are available from the late-19th century, beginning with the 1882-83 German International Polar Year Expedition. Many more exist from the 20th century, notably from the South Georgia Surveys in the 1950s. An assessment of the value of the photographs indicates that spatial coverage is variable, many lack reference features to pinpoint glacier positions and, in the case of smaller glaciers, the presence of snowcover makes it difficult to define the ice edge. Nevertheless, the photographs provide useful corroboration of more advanced glacier positions during the late-19th century and recession of smaller mountain and valley glaciers during the mid-20th century, while larger tidewater and sea-calving glaciers generally remained in relatively advanced positions until the 1980s. Since then, nearly all the glaciers have retreated; some of these retreats have been dramatic and a number of small mountain glaciers have fragmented or disappeared. The response of the glaciers can be related to synoptic-scale warming, particularly since the 1950s, moderated by individual glacier geometry and topography.

  13. The relationship between 19th century BMIs and family size: Economies of scale and positive externalities.

    PubMed

    Carson, Scott Alan

    2015-04-01

    The use of body mass index values (BMI) to measure living standards is now a well-accepted method in economics. Nevertheless, a neglected area in historical studies is the relationship between 19th century BMI and family size, and this relationship is documented here to be positive. Material inequality and BMI are the subject of considerable debate, and there was a positive relationship between BMI and wealth and an inverse relationship with inequality. After controlling for family size and wealth, BMI values were related with occupations, and farmers and laborers had greater BMI values than workers in other occupations.

  14. The relationship between 19th century BMIs and family size: Economies of scale and positive externalities.

    PubMed

    Carson, Scott Alan

    2015-04-01

    The use of body mass index values (BMI) to measure living standards is now a well-accepted method in economics. Nevertheless, a neglected area in historical studies is the relationship between 19th century BMI and family size, and this relationship is documented here to be positive. Material inequality and BMI are the subject of considerable debate, and there was a positive relationship between BMI and wealth and an inverse relationship with inequality. After controlling for family size and wealth, BMI values were related with occupations, and farmers and laborers had greater BMI values than workers in other occupations. PMID:25555643

  15. 19th-century academic examinations for physicians in the United States Army Medical Department.

    PubMed Central

    Sohn, A P

    1994-01-01

    During the latter half of the 19th century, the United States Army commissioned medical officers or hired civilian physicians to serve its troops. The civilian physician signed a contract for services, and the candidate for a commission was subjected to rigorous examinations before becoming an officer. The rigorous testing of prospective medical officers was necessary because of the lack of standardization in the education of physicians. Examples of the test, statistics, and individual records show how the Army dealt with unqualified candidates. Images PMID:8048241

  16. Parents and children: ideas of heredity in the 19th century.

    PubMed

    Waller, John C

    2003-06-01

    The concept of heredity played a powerful role in structuring 19th-century debates over sickness, morality, class, race, education, social change and evolution. But there was very little agreement as to which qualities were heritable and how new hereditary variants were acquired. In consequence, notions of heredity existed in a wide variety of forms, expressing anything from extreme determinism and a belief in the incorrigibility of individuals, social and racial groups, to unleavened optimism, and a faith in ultimate human perfectibility. This article explores these rich hereditarian discourses to convey an impression of a century that was at least as preoccupied with the concept of biological inheritance as we are today.

  17. SOLAR WIND HEAVY IONS OVER SOLAR CYCLE 23: ACE/SWICS MEASUREMENTS

    SciTech Connect

    Lepri, S. T.; Landi, E.; Zurbuchen, T. H.

    2013-05-01

    Solar wind plasma and compositional properties reflect the physical properties of the corona and its evolution over time. Studies comparing the previous solar minimum with the most recent, unusual solar minimum indicate that significant environmental changes are occurring globally on the Sun. For example, the magnetic field decreased 30% between the last two solar minima, and the ionic charge states of O have been reported to change toward lower values in the fast wind. In this work, we systematically and comprehensively analyze the compositional changes of the solar wind during cycle 23 from 2000 to 2010 while the Sun moved from solar maximum to solar minimum. We find a systematic change of C, O, Si, and Fe ionic charge states toward lower ionization distributions. We also discuss long-term changes in elemental abundances and show that there is a {approx}50% decrease of heavy ion abundances (He, C, O, Si, and Fe) relative to H as the Sun went from solar maximum to solar minimum. During this time, the relative abundances in the slow wind remain organized by their first ionization potential. We discuss these results and their implications for models of the evolution of the solar atmosphere, and for the identification of the fast and slow wind themselves.

  18. The onset of the solar active cycle 22

    NASA Technical Reports Server (NTRS)

    Ahluwalia, H. S.

    1989-01-01

    There is a great deal of interest in being able to predict the main characteristics of a solar activity cycle (SAC). One would like to know, for instance, how large the amplitude (R sub m) of a cycle is likely to be, i.e., the annual mean of the sunspot numbers at the maximum of SAC. Also, how long a cycle is likely to last, i.e., its period. It would also be interesting to be able to predict the details, like how steep the ascending phase of a cycle is likely to be. Questions like these are of practical importance to NASA in planning the launch schedule for the low altitude, expensive spacecrafts like the Hubble Space Telescope, the Space Station, etc. Also, one has to choose a proper orbit, so that once launched the threat of an atmospheric drag on the spacecraft is properly taken into account. Cosmic ray data seem to indicate that solar activity cycle 22 will surpass SAC 21 in activity. The value of R sub m for SAC 22 may approach that of SAC 19. It would be interesting to see whether this prediction is borne out. Researchers are greatly encouraged to proceed with the development of a comprehensive prediction model which includes information provided by cosmic ray data.

  19. High Energy Particle Events in Solar Cycles 23 and 24

    NASA Astrophysics Data System (ADS)

    Thakur, N.; Gopalswamy, N.; Makela, P. A.; Yashiro, S.; Akiyama, S.; Xie, H.

    2014-12-01

    We present a study of high-energy solar energetic particle (SEP) events in solar cycles 23 and 24 using GOES data. We selected large SEP events, which showed intensity enhancements in the >500 MeV and >700 MeV GOES energy channels. A study of cycle 24 and the first half of cycle 23 ground level enhancements (GLEs) by Gopalswamy et al. 2014 showed that typically, SEP events with intensity enhancement at >700 MeV have been associated with GLEs. We have extended the survey to cover the whole cycle 23. Our preliminary survey confirms this to be true for all except for three cases. There were two GLEs (1998/05/06 and 2006/12/06) for which a clear increase in >700 MeV protons was not observed by GOES. There was one high energy SEP event (2000/11/08), for which GOES observed >700 MeV protons but no GLE was produced. Here we compare all the high-energy particle events from cycles 23 and 24 with GLEs. We also compare energy spectra of all high-energy SEP events with those that produced GLEs. Work supported by NASA's Living with a Star Program. Ref.: Gopalswamy et al. 2014, GRL, 41, 2673

  20. Solar Cycle Length and Northern Hemisphere mean temperature revisited.

    NASA Astrophysics Data System (ADS)

    Thejll, P.

    2009-04-01

    The statistical relationship between the smoothed curve for solar cycle length and northern hemisphere land mean temperature has been a source of investigation in the question of whether and how much the Sun influences climate variations. The relationship was widely discussed following the 1991 paper by Friis-Christensen and Lassen and was updated in 2000 by Thejll and Lassen. Data for one more solar cycle has now accumulated, and the relationship is again reviewed and discussed. We derive and show the updated SCL and mean temperature curves. The relationship between the two is analysed using standard statistical methods. Additional climate forcing factors are introduced to improve the fit. Changes in the historical part of the mean temperature curve has occurred which modifies the previously seen relationship, and this is discussed.

  1. The Solar Cycle and, How Do We Know What We Know?

    NASA Technical Reports Server (NTRS)

    Adams, Mitzi

    2013-01-01

    Through the use of observations, mathematics, mathematical tools (such as graphs), inference, testing, and prediction we have gathered evidence that there are sunspots, a solar cycle, and have begun to understand more about our star, the Sun. We are making progress in understanding the cause of the solar cycle. We expect solar cycle 24 to peak soon. Cycle 24 will be the smallest cycle in 100 years.

  2. Solar grand and super-grand cycles derived with PCA from the solar background magnetic field

    NASA Astrophysics Data System (ADS)

    Zharkova, Valentina; Shepherd, Simon; Zharkov, Sergei; Popova, Elena

    2016-04-01

    We present principal components analysis (PCA) of temporal magnetic field variations over the solar cycles 21-24. These PCs reveal two main magnetic waves with close frequencies (covering 40% of data variance) travelling from the opposite hemispheres with an increasing phase shift. Extrapolation of these PCs through their summary curve backward for 2000 years reveals a number of ~350-year grand cycles and about 2000 super-grand cycles superimposed on 22 year-cycles with the features showing a remarkable resemblance to sunspot activity reported in the past. The summary curve calculated forward for the next millennium predicts further three grand cycles with the closest grand minimum occurring in the forthcoming cycles 25-27 when the two magnetic field waves have a phase shift of 11 years. We explore a role of other independent components derived with PCA and their expected effects on the resulting summary curve, or solar activity curve. We suggest that these grand and super-grand cycles can be produced by two dynamo waves generated in different layers with close frequencies whose interaction leads to beating effects that is discussed in the work by Popova et al (2016) presented here. This approach opens a new era in investigation and prediction of solar activity on long-term timescales.

  3. Solar/gas Rankine/Rankine-cycle heat pump assessment

    NASA Astrophysics Data System (ADS)

    Khalifa, H. E.; Melikian, G.

    1982-07-01

    This report contains an assessment of the technical and economic feasibility of Rankine-cycle solar-augmented gas-fired heat pumps (SAGFHP) for multi-family residential and light-commercial applications. The SAGFHP design considered in this report is based on the successful UTRC turbocompressor system which has been tested both in the laboratory and in a solar cooling installation in Phoenix. AZ. An hour-by-hour modeling of present-design SAGFHP performance in multi-family and office buildings in New York, Wisconsin, Nebraska and Oregon indicated that, even without solar augmentation, primary energy savings of up 17% and 31% could be achieved relative to advanced furnace plus electric air conditioning systems and electric heat pumps, respectively.

  4. Design and fabrication of brayton cycle solar heat receiver

    NASA Technical Reports Server (NTRS)

    Mendelson, I.

    1971-01-01

    A detail design and fabrication of a solar heat receiver using lithium fluoride as the heat storage material was completed. A gas flow analysis was performed to achieve uniform flow distribution within overall pressure drop limitations. Structural analyses and allowable design criteria were developed for anticipated environments such as launch, pressure containment, and thermal cycling. A complete heat receiver assembly was fabricated almost entirely from the refractory alloy, niobium-1% zirconium.

  5. Developing a Solar Magnetic Catalog Spanning Four Cycles

    NASA Astrophysics Data System (ADS)

    Werginz, Zachary; Munoz-Jaramillo, Andres; DeLuca, Michael D.; Vargas Acosta, Juan Pablo; Vargas Dominguez, Santiago; Zhang, Jie; Longcope, Dana; Martens, Petrus C.

    2016-05-01

    Bipolar magnetic regions (BMRs) are the cornerstone of solar cycle propagation, the building blocks that give structure to the solar atmosphere, and the origin of the majority of space weather events. However, in spite of their importance, there is no homogeneous BMR catalog spanning the era of systematic solar magnetic field measurements. Here we present the results of an ongoing project to address this deficiency applying the Bipolar Active Region Detection (BARD) code to magnetograms from the 512 Channel of the Kitt Peak Vaccum Telescope, SOHO/MDI, and SDO/HMI.The BARD code automatically identifies BMRs and tracks them as they are rotated by differential rotation. The output of the automatic detection is supervised by a human observer to correct possible mistakes made by the automatic algorithm (like incorrect pairings and tracking mislabels). Extra passes are made to integrate fragmented regions as well as to balance the flux between BMR polarities. At the moment, our BMR database includes 6,885 unique objects (detected and tracked) belonging to four separate solar cycles (21-24).

  6. Vitalizing four solar cycles of Kitt Peak synoptic magnetograms

    NASA Astrophysics Data System (ADS)

    Harvey, John; Munoz-Jaramillo, Andres

    2015-04-01

    Solar magnetism spans many decades of spatial and temporal scales. Studies of the larger end of these ranges requires frequent observations of the full solar disk over long durations. To aid investigations of the solar cycle and individual active region evolution, nearly daily magnetograms have been observed from Kitt Peak during solar cycles 20-23. These data were used in real time for space weather predictions, and archived observations have so far served more than 1500 refereed research publications. Some of the observations suffered from various instrumental problems. We report ongoing efforts to restore and correct observations from 1970-2003 in order to maximize the scientific value of the observations. The main improvements are reductions of certain instrumental noise, signal biases, and imperfect scanning geometry. The improved data will be used the make synchronic and diachronic synoptic maps, a catalog of active region properties, and estimates of tracer flow patterns.In addition to base funding from NSF, NASA and NOAA provided substantial support of the Kitt Peak synoptic observations.

  7. ON THE 'EXTENDED' SOLAR CYCLE IN CORONAL EMISSION

    SciTech Connect

    Robbrecht, E.; Wang, Y.-M.; Sheeley, N. R.; Rich, N. B. E-mail: yi.wang@nrl.navy.mi E-mail: nathan.rich@nrl.navy.mi

    2010-06-10

    Butterfly diagrams (latitude-time plots) of coronal emission show a zone of enhanced brightness that appears near the poles just after solar maximum and migrates toward lower latitudes; a bifurcation seems to occur at sunspot minimum, with one branch continuing to migrate equatorward with the sunspots of the new cycle and the other branch heading back to the poles. The resulting patterns have been likened to those seen in torsional oscillations and have been taken as evidence for an extended solar cycle lasting over {approx}17 yr. In order to clarify the nature of the overlapping bands of coronal emission, we construct butterfly diagrams from green-line simulations covering the period 1967-2009 and from 19.5 nm and 30.4 nm observations taken with the Extreme-Ultraviolet Imaging Telescope during 1996-2009. As anticipated from earlier studies, we find that the high-latitude enhancements mark the footpoint areas of closed loops with one end rooted outside the evolving boundaries of the polar coronal holes. The strong underlying fields were built up over the declining phase of the cycle through the poleward transport of active-region flux by the surface meridional flow. Rather than being a precursor of the new-cycle sunspot activity zone, the high-latitude emission forms a physically distinct, U-shaped band that curves upward again as active-region fields emerge at midlatitudes and reconnect with the receding polar-hole boundaries. We conclude that the so-called extended cycle in coronal emission is a manifestation not of early new-cycle activity, but of the poleward concentration of old-cycle trailing-polarity flux by meridional flow.

  8. Tuberculosis Epidemiology and Selection in an Autochthonous Siberian Population from the 16th-19th Century

    PubMed Central

    Dabernat, Henri; Thèves, Catherine; Bouakaze, Caroline; Nikolaeva, Dariya; Keyser, Christine; Mokrousov, Igor; Géraut, Annie; Duchesne, Sylvie; Gérard, Patrice; Alexeev, Anatoly N.; Crubézy, Eric; Ludes, Bertrand

    2014-01-01

    Tuberculosis is one of most ancient diseases affecting human populations. Although numerous studies have tried to detect pathogenic DNA in ancient skeletons, the successful identification of ancient tuberculosis strains remains rare. Here, we describe a study of 140 ancient subjects inhumed in Yakutia (Eastern Siberia) during a tuberculosis outbreak, dating from the 16th–19th century. For a long time, Yakut populations had remained isolated from European populations, and it was not until the beginning of the 17th century that first contacts were made with European settlers. Subsequently, tuberculosis spread throughout Yakutia, and the evolution of tuberculosis frequencies can be tracked until the 19th century. This study took a multidisciplinary approach, examining historical and paleo-epidemiological data to understand the impact of tuberculosis on ancient Yakut population. In addition, molecular identification of the ancient tuberculosis strain was realized to elucidate the natural history and host-pathogen co-evolution of human tuberculosis that was present in this population. This was achieved by the molecular detection of the IS6110 sequence and SNP genotyping by the SNaPshot technique. Results demonstrated that the strain belongs to cluster PGG2-SCG-5, evocating a European origin. Our study suggests that the Yakut population may have been shaped by selection pressures, exerted by several illnesses, including tuberculosis, over several centuries. This confirms the validity and necessity of using a multidisciplinary approach to understand the natural history of Mycobacterium tuberculosis infection and disease. PMID:24587092

  9. The 'Ajuda Paralyses': history of a neuropsychiatric debate in mid-19th-century Portugal.

    PubMed

    Fontoura, Paulo

    2010-10-01

    The second half of the 19th century witnessed an increasing interest in neurology and psychiatry by Portuguese physicians, in parallel with the overall development of these disciplines in other countries. This process is reflected in the numerous case report publications as well as in debates taking place at the Lisbon Society of Medical Sciences, the major scientific forum of that time. The 'Ajuda Paralyses' were a mysterious succession of epidemics that occurred during 1860-64 in the Ajuda asylum for cholera and yellow fever orphans, which were extensively discussed during 1865-66 by Bernardino Antonio Gomes, Antonio Maria Barbosa, Abel Jordão and Eduardo Motta. Studying this debate helps understand the initial stages of development and the great interest that 'nervous diseases' had for Portuguese clinicians in the mid-19th century and possibly provides one of the first modern descriptions of nutrition-related polyradiculoneuropathy and the ocular findings associated with avitaminosis A. This debate took place at a decisive time for the scientific development of neurology and psychiatry, concurrent with the widespread application of the clinical-anatomical method and neuropathology to the study of diseases of the nervous system, which would set the foundations for our own modern pathophysiological framework. Therefore, the 'Ajuda paralyses' debate also provides a good basis for a discussion on the evolution of the concepts of hysteria and psychosomatic disease and the description of peripheral neuropathy from among a wealth of other entities that did not withstand the test of science.

  10. [Medecine, Law, and Knowledge Production about the "Civilized" War in the Long 19th Century].

    PubMed

    Goltermann, Svenja

    2015-01-01

    The aim to 'civilize' warfare accompanied Medicine and International Law ever since the mid-19th century. However, the entanglement of Medicine and Law, crucial for such an endeavour, has not been taken into consideration so far; likewise, the huge importance of medical knowledge for the perception of wars and their ramifications did not garner much attention in historical research. Hence, by focusing on the 'long' 19th century, this paper shows, firstly, that the production of surgical knowledge during warfare aimed at measuring the effects of combat on human bodies in order to develop prognostic medical knowledge for future wars, as well as maintaining the combat strength of soldiers. Moreover, this knowledge production during warfare strived for the enhancement of medical competence in the diagnosis and treatment of wounds in general. Secondly, I show that this medical knowledge was not only relevant for warfare, but also crucial for the design of International Law: it served to nourish the debates among the so called 'civilized' nations about legitimate and illegitimate weaponry and warfare. PMID:26902055

  11. [From spermatic animalcules to sperm cells: the reconceptualization of generation in the 19th century].

    PubMed

    Vienne, Florence

    2009-09-01

    At the end of the 18th and still at the beginning of the 19th century most naturalists considered spermatic animalcules to be parasites of the seminal fluid that played no role in procreation. This view was progressively questioned by 19th century physiologists. They gradually redefined the spermatic animals as (cellular) products of the male organism, as agents of fertilization and bearers of the male heredity material. This article discusses this change from two different perspectives: on a microhistorical level, it analyzes the experimental research of the naturalist Lazzaro Spallanzani (1729-1799) and of the physiologist Albert Kölliker (1817-1905) in order to show how spermatozoa were turned into a new epistemic object of biology--the sperm cell. Further, it asks how the role of the reconceptualization of spermatic animalcules affected the long-term transformations that gave rise of our modern understanding of heredity, generation and the sexed body. By combining these two perspectives, the article aims to connect historiographies that are often kept separate: the macrohistorical narratives about gender and the body in the modern age and the microhistorical studies of biomedical practices and objects.

  12. [Medecine, Law, and Knowledge Production about the "Civilized" War in the Long 19th Century].

    PubMed

    Goltermann, Svenja

    2015-01-01

    The aim to 'civilize' warfare accompanied Medicine and International Law ever since the mid-19th century. However, the entanglement of Medicine and Law, crucial for such an endeavour, has not been taken into consideration so far; likewise, the huge importance of medical knowledge for the perception of wars and their ramifications did not garner much attention in historical research. Hence, by focusing on the 'long' 19th century, this paper shows, firstly, that the production of surgical knowledge during warfare aimed at measuring the effects of combat on human bodies in order to develop prognostic medical knowledge for future wars, as well as maintaining the combat strength of soldiers. Moreover, this knowledge production during warfare strived for the enhancement of medical competence in the diagnosis and treatment of wounds in general. Secondly, I show that this medical knowledge was not only relevant for warfare, but also crucial for the design of International Law: it served to nourish the debates among the so called 'civilized' nations about legitimate and illegitimate weaponry and warfare.

  13. Tuberculosis epidemiology and selection in an autochthonous Siberian population from the 16th-19th century.

    PubMed

    Dabernat, Henri; Thèves, Catherine; Bouakaze, Caroline; Nikolaeva, Dariya; Keyser, Christine; Mokrousov, Igor; Géraut, Annie; Duchesne, Sylvie; Gérard, Patrice; Alexeev, Anatoly N; Crubézy, Eric; Ludes, Bertrand

    2014-01-01

    Tuberculosis is one of most ancient diseases affecting human populations. Although numerous studies have tried to detect pathogenic DNA in ancient skeletons, the successful identification of ancient tuberculosis strains remains rare. Here, we describe a study of 140 ancient subjects inhumed in Yakutia (Eastern Siberia) during a tuberculosis outbreak, dating from the 16(th)-19(th) century. For a long time, Yakut populations had remained isolated from European populations, and it was not until the beginning of the 17(th) century that first contacts were made with European settlers. Subsequently, tuberculosis spread throughout Yakutia, and the evolution of tuberculosis frequencies can be tracked until the 19(th) century. This study took a multidisciplinary approach, examining historical and paleo-epidemiological data to understand the impact of tuberculosis on ancient Yakut population. In addition, molecular identification of the ancient tuberculosis strain was realized to elucidate the natural history and host-pathogen co-evolution of human tuberculosis that was present in this population. This was achieved by the molecular detection of the IS6110 sequence and SNP genotyping by the SNaPshot technique. Results demonstrated that the strain belongs to cluster PGG2-SCG-5, evocating a European origin. Our study suggests that the Yakut population may have been shaped by selection pressures, exerted by several illnesses, including tuberculosis, over several centuries. This confirms the validity and necessity of using a multidisciplinary approach to understand the natural history of Mycobacterium tuberculosis infection and disease.

  14. Classic articles of 19th-century American neurologists: a critical review.

    PubMed

    Lanska, Douglas J

    2002-06-01

    The purpose of this article is to critically review citation classics of 19th-century members of the American Neurological Association (ANA), and to elaborate what these works contributed and why they continue to be important. Most classic articles of 19th-century American neurologists were initial or early descriptions of clinical conditions, diseases, or procedures. These include descriptions by Beard of the Jumping Frenchmen of Maine; by Sachs of "amaurotic family idiocy" (Tay-Sachs disease); by Hun of the lateral medullary syndrome; by Mitchell of phantom limbs; and by Dana of familial tremor. Few of these were the initial description, although most were clear and fairly complete by modern standards. Several citation classics were cited mainly as a point of comparison with later events or developments, including those by Corning on spinal anesthesia, Bartholow on electrical stimulation of the brain, Mitchell on the status of American psychiatry, and Starr on childhood brain tumors. The reports of Corning, Bartholow, and Mitchell have been the subjects of continued controversy. The only examples of basic neuroscience among the citation classics are the classic studies by Onuf and Collins involving ablation of portions of the sympathetic chain in cats, and Onuf's description of the nucleus of Onuf in the human spinal cord. Onuf's basic science work was made possible by a unique and short-lived multidisciplinary research environment created at the New York State Pathological Institute for the scientific investigation of insanity and neurologic diseases.

  15. Extending the African instrumental record to the early 19th century

    SciTech Connect

    Nicholson, S.E.

    1997-11-01

    This paper describes progress toward the production of a data set that extends the African climate record back to the beginning of the 19th century. Qualitative documentary evidence, lake-level fluctuations and other proxy indicators are combined with historical rainfall records to produce regional time series. The data set has relatively high temporal and spatial resolution. The conceptualization is based on a climatic regionalization produced using modern data and an anomaly method in previous historical reconstructions. The data set provides information for some 100 regions with a 1 to 5 year resolution for most of the nineteenth century. Three to five quantitative classes of rainfall are utilized in the data set. Here, the available information to produce this record is summarized. The methodology utilized to combine proxy data and observations to produce a quantitative rainfall data set is described. This historical data set is compared with actual rainfall records for select regions where both are available. This comparison indicates the reliability of the proxy African data set. An analysis of the historical record indicates that the main characteristics of rainfall variability evident in the modern African record are also apparent in the 19th century record. 5 figs.

  16. [The reception of homoeopathy among Polish physicians in the 19th century].

    PubMed

    Plonka-Syroka, B

    1997-01-01

    The 19th century Polish academic community showed a consistently negative attitude towards the Hahnemannian doctrine. On the other hand, homoeopathy spread more and more widely in Polish society. Popular homoeopathic journals and advisory literature expressed scepticism towards science and materialism or adopted viewpoints close to spiritualism. Furthermore these publications aimed at linking homoeopathy with traditional religious folklore. Homoeopathic domestic medical literature gave the opportunity for medical self-help at a time when relatively few people had access to professional medical services - due to financial reasons in the cities and due to a lack of physicians in rural areas. Additionally homoepathy offered hope to those whose ailments could not be cured by the professional academic medicine. The reception of homoeopathy in Poland was nevertheless limited. The doctrine was commonly known nowhere near as popular as the medical self-help that derived from what is called traditional "folk medicine". Also homoeopathy never was a serious competitor to the therapeutic arsenal of late 19th century academic medicine.

  17. PERIASTRON PASSAGE TRIGGERING OF THE 19TH CENTURY ERUPTIONS OF ETA CARINAE

    SciTech Connect

    Kashi, Amit; Soker, Noam E-mail: soker@physics.technion.ac.i

    2010-11-01

    We reconstruct the evolution of {eta} Car in the last two centuries under the assumption that the two 19th century eruptions were triggered by periastron passages and through this reconstruction constrain the binary parameters. The beginning of the lesser eruption (LE) at the end of the 19th century occurred when the system was very close to periastron passage, suggesting that the secondary triggered the LE. We assume that the 1838-1858 great eruption (GE) was triggered by a periastron passage as well. We also assume that mass transferred from the primary to the secondary star accounts for the extra energy of the GE. With these assumptions we constrain the total mass of the binary system to be M = M{sub 1} + M{sub 2} {approx}> 250 M{sub sun}. These higher than commonly used masses better match the observed luminosity with stellar evolutionary tracks. Including mass loss by the two stars and mass transfer from the primary to the secondary we obtain a good match of periastron passages to the two peaks in the light curve of the GE. Based on these findings and a similar behavior of P Cygni, we speculate that major luminous blue variable eruptions are triggered by stellar companions and that in extreme cases a short duration event with a huge mass transfer rate can lead to a bright transient event on timescales of weeks to months (a 'supernova impostor').

  18. Geometric frustration on a 1/9th site depleted triangular lattice

    NASA Astrophysics Data System (ADS)

    Hopkinson, John; Beck, Jarrett

    2013-03-01

    In the searches both for new spin liquid and spin ice (artificial and macroscopic) candidates, geometrically frustrated two-dimensional spin systems have played a prominent role. Here we present a study of the classical antiferromagnetic Ising (AFI) model on the sorrel net, a 1/9th site depleted and 1/7th bond depleted triangular lattice. The AFI model on this corner-shared triangle net is found to have a large residual entropy per spin S/N = 0 . 48185 +/- 0 . 00008 , indicating the sorrel net is highly geometrically frustrated. Anticipating that it may be difficult to achieve perfect bond depletion, we investigate the physics resulting from turning back on the depleted bonds (J2). We present the phase diagram, analytic expressions for the long range partially ordered ground state spin structure for antiferromagnetic J2 and the short range ordered ground state spin structure for ferromagnetic J2, the magnetic susceptibility and the static structure factor. We briefly comment on the possibility that artificial spin ice on the sorrel lattice could by made, and on a recent report [T. D. Keene et al., Dalton Trans. 40 2983 (2011)] of the creation of a 1/9th depleted cobalt hydroxide oxalate. This work was supported by NSERC (JMH) and NSERC USRA (JJB)

  19. IS SOLAR CYCLE 24 PRODUCING MORE CORONAL MASS EJECTIONS THAN CYCLE 23?

    SciTech Connect

    Wang, Y.-M.; Colaninno, R. E-mail: robin.colaninno@nrl.navy.mil

    2014-04-01

    Although sunspot numbers are roughly a factor of two lower in the current cycle than in cycle 23, the rate of coronal mass ejections (CMEs) appears to be at least as high in 2011-2013 as during the corresponding phase of the previous cycle, according to three catalogs that list events observed with the Large Angle and Spectrometric Coronagraph (LASCO). However, the number of CMEs detected is sensitive to such factors as the image cadence and the tendency (especially by human observers) to under-/overcount small or faint ejections during periods of high/low activity. In contrast to the total number, the total mass of CMEs is determined mainly by larger events. Using the mass measurements of 11,000 CMEs given in the manual CDAW catalog, we find that the mass loss rate remains well correlated with the sunspot number during cycle 24. In the case of the automated CACTus and SEEDS catalogs, the large increase in the number of CMEs during cycle 24 is almost certainly an artifact caused by the near-doubling of the LASCO image cadence after mid-2010. We confirm that fast CMEs undergo a much stronger solar-cycle variation than slow ones, and that the relative frequency of slow and less massive CMEs increases with decreasing sunspot number. We conclude that cycle 24 is not only producing fewer CMEs than cycle 23, but that these ejections also tend to be slower and less massive than those observed one cycle earlier.

  20. Is Solar Cycle 24 Producing More Coronal Mass Ejections Than Cycle 23?

    NASA Astrophysics Data System (ADS)

    Wang, Y.-M.; Colaninno, R.

    2014-04-01

    Although sunspot numbers are roughly a factor of two lower in the current cycle than in cycle 23, the rate of coronal mass ejections (CMEs) appears to be at least as high in 2011-2013 as during the corresponding phase of the previous cycle, according to three catalogs that list events observed with the Large Angle and Spectrometric Coronagraph (LASCO). However, the number of CMEs detected is sensitive to such factors as the image cadence and the tendency (especially by human observers) to under-/overcount small or faint ejections during periods of high/low activity. In contrast to the total number, the total mass of CMEs is determined mainly by larger events. Using the mass measurements of 11,000 CMEs given in the manual CDAW catalog, we find that the mass loss rate remains well correlated with the sunspot number during cycle 24. In the case of the automated CACTus and SEEDS catalogs, the large increase in the number of CMEs during cycle 24 is almost certainly an artifact caused by the near-doubling of the LASCO image cadence after mid-2010. We confirm that fast CMEs undergo a much stronger solar-cycle variation than slow ones, and that the relative frequency of slow and less massive CMEs increases with decreasing sunspot number. We conclude that cycle 24 is not only producing fewer CMEs than cycle 23, but that these ejections also tend to be slower and less massive than those observed one cycle earlier.

  1. Multiple Evidence of Intense Solar Proton Events During Solar Cycle 13

    NASA Astrophysics Data System (ADS)

    Peristykh, Alexei

    We present evidence of intense solar proton events in the last decade of the XIX century based on diverse solar and geophysical data. One of those events (July 15, 1892) was observed by George Hale as a 'remarkable solar disturbance'. There appears to be a number of intense solar flare events at that period concurrent with solar cycle 13. Besides white-light flares, there were more numerous storm sudden commencements (SSC) of high amplitude ( 40 nT), noticeable enhanced annual sums of the Aa index, more frequent observation of very bright aurorae borealis in North America. This phenomenon is also revealed from data on nitrates in polar ice and cosmogenic isotopes in terrestrial archives.

  2. Background solar irradiance spectrum at high and low phases of the solar activity cycle

    NASA Astrophysics Data System (ADS)

    Vázquez Ramió, H.; Roca Cortés, T.; Régulo, C.

    2002-12-01

    Two data series of disk integrated solar irradiance, taken by the Variability of the solar IRradiance and Gravity Oscillations (VIRGO) experiment on board the Solar and Heliospheric Observatory (SoHO) mission, corresponding to epochs of minimum and maximum solar activity have been analysed in order to study the background signal of the associated power spectra. We fit the most apparent convective structures that appear at low frequencies in the spectrum as well as non-periodic components. We aim to compare the results found in the three observed bands (centered in λ=402nm, λ=500nm and λ=862nm) as well as to find dependences of the non-periodic convective structures parameters with the solar cycle.

  3. Solar UV Spectral Irradiance Measured by SUSIM During Solar Cycle 22 and 23

    NASA Astrophysics Data System (ADS)

    Morrill, J. S.; Floyd, L. E.; McMullin, D. R.

    2011-12-01

    Understanding the impact of solar variability on terrestrial climate requires detailed knowledge of both solar spectral irradiance (SSI) and total solar irradiance (TSI). Observations of SSI in the ultraviolet (UV) have been made by various space-based missions since 1978. Of these missions, the Upper Atmosphere Research Satellite (UARS) included the Solar Ultraviolet Spectral Irradiance Monitor (SUSIM) experiment which measured the UV SSI from 1991 into 2005. In this talk, we present the UV spectral irradiance observations from SUSIM on UARS during solar cycles 22 and 23 along with results of a recent review of the calibration, stability, and in-flight performance. Another more recent mission is the Solar Radiation and Climate Experiment (SORCE) satellite which carries the Solar-Stellar Irradiance Comparison Experiment (SOLSTICE) and Solar Irradiance Monitor (SIM). Together, the SORCE instruments have measured the UV, Visible, and IR SSI over the period of 2003 to the present. This talk will include a comparison between SUSIM and SORCE during the period of overlapping observations as well as comparisons of UV spectra observed at various times, particularly during the last two solar minima. These comparisons show that the UV observations by SORCE are inconsistent with those measured by SUSIM.

  4. SOLAR-CYCLE VARIATION OF SOUND SPEED NEAR THE SOLAR SURFACE

    SciTech Connect

    Rabello-Soares, M. C.

    2012-02-01

    We present evidence that the sound-speed variation with solar activity has a two-layer configuration, similar to the one observed below an active region, which consists of a negative layer near the solar surface and a positive one in the layer immediately below the first one. Frequency differences between the activity minimum and maximum of solar cycle 23, obtained applying global helioseismology to the Michelson Doppler Imager on board the Solar and Heliospheric Observatory, is used to determine the sound-speed variation from below the base of the convection zone to a few Mm below the solar surface. We find that the sound speed at solar maximum is smaller than at solar minimum at the limit of our determination (5.5 Mm). The min-to-max difference decreases in absolute values until {approx}7 Mm. At larger depths, the sound speed at solar maximum is larger than at solar minimum and the difference increases with depth until {approx}10 Mm. At this depth, the relative difference ({delta}c{sup 2}/c{sup 2}) is less than half of the value observed at the lowest depth determination. At deeper layers, it slowly decreases with depth until there is no difference between maximum and minimum activity.

  5. Space Weather and the Ground-Level Solar Proton Events of the 23rd Solar Cycle

    NASA Astrophysics Data System (ADS)

    Shea, M. A.; Smart, D. F.

    2012-10-01

    Solar proton events can adversely affect space and ground-based systems. Ground-level events are a subset of solar proton events that have a harder spectrum than average solar proton events and are detectable on Earth's surface by cosmic radiation ionization chambers, muon detectors, and neutron monitors. This paper summarizes the space weather effects associated with ground-level solar proton events during the 23rd solar cycle. These effects include communication and navigation systems, spacecraft electronics and operations, space power systems, manned space missions, and commercial aircraft operations. The major effect of ground-level events that affect manned spacecraft operations is increased radiation exposure. The primary effect on commercial aircraft operations is the loss of high frequency communication and, at extreme polar latitudes, an increase in the radiation exposure above that experienced from the background galactic cosmic radiation. Calculations of the maximum potential aircraft polar route exposure for each ground-level event of the 23rd solar cycle are presented. The space weather effects in October and November 2003 are highlighted together with on-going efforts to utilize cosmic ray neutron monitors to predict high energy solar proton events, thus providing an alert so that system operators can possibly make adjustments to vulnerable spacecraft operations and polar aircraft routes.

  6. Solar cycle variation of the statistical distribution of the solar wind ɛ parameter and its constituent variables

    NASA Astrophysics Data System (ADS)

    Tindale, E.; Chapman, S. C.

    2016-06-01

    We use 20 years of Wind solar wind observations to investigate the solar cycle variation of the solar wind driving of the magnetosphere. For the first time, we use generalized quantile-quantile plots to compare the statistical distribution of four commonly used solar wind coupling parameters, Poynting flux, B2, the ɛ parameter, and vB, between the maxima and minima of solar cycles 23 and 24. We find the distribution is multicomponent and has the same functional form at all solar cycle phases; the change in distribution is captured by a simple transformation of variables for each component. The ɛ parameter is less sensitive than its constituent variables to changes in the distribution of extreme values between successive solar maxima. The quiet minimum of cycle 23 manifests only in lower extreme values, while cycle 24 was less active across the full distribution range.

  7. Solar cycle in current reanalyses: (non)linear attribution study

    NASA Astrophysics Data System (ADS)

    Kuchar, A.; Sacha, P.; Miksovsky, J.; Pisoft, P.

    2014-12-01

    This study focusses on the variability of temperature, ozone and circulation characteristics in the stratosphere and lower mesosphere with regard to the influence of the 11 year solar cycle. It is based on attribution analysis using multiple nonlinear techniques (Support Vector Regression, Neural Networks) besides the traditional linear approach. The analysis was applied to several current reanalysis datasets for the 1979-2013 period, including MERRA, ERA-Interim and JRA-55, with the aim to compare how this type of data resolves especially the double-peaked solar response in temperature and ozone variables and the consequent changes induced by these anomalies. Equatorial temperature signals in the lower and upper stratosphere were found to be sufficiently robust and in qualitative agreement with previous observational studies. The analysis also pointed to the solar signal in the ozone datasets (i.e. MERRA and ERA-Interim) not being consistent with the observed double-peaked ozone anomaly extracted from satellite measurements. Consequently the results obtained by linear regression were confirmed by the nonlinear approach through all datasets, suggesting that linear regression is a relevant tool to sufficiently resolve the solar signal in the middle atmosphere. Furthermore, the seasonal dependence of the solar response was also discussed, mainly as a source of dynamical causalities in the wave propagation characteristics in the zonal wind and the induced meridional circulation in the winter hemispheres. The hypothetical mechanism of a weaker Brewer Dobson circulation was reviewed together with discussion of polar vortex stability.

  8. A new method for forecasting the solar cycle descent time

    NASA Astrophysics Data System (ADS)

    Kakad, Bharati; Kakad, Amar; Sai Ramesh, Durbha

    2015-08-01

    The prediction of an extended solar minimum is extremely important because of the severity of its impact on the near-earth space. Here, we present a new method for predicting the descent time of the forthcoming solar cycle (SC); the method is based on the estimation of the Shannon entropy. We use the daily and monthly smoothed international sunspot number. For each nth SC, we compute the parameter [Tpre]n by using information on the descent and ascent times of the n - 3th and nth SCs, respectively. We find that [Tpre] of nth SC and entropy can be effectively used to predict the descent time of the n + 2th SC. The correlation coefficient between [Td]n+2 - [Tpre]n and [E]n is found to be 0.95. Using these parameters the prediction model is developed. Solar magnetic field and F10.7 flux data are available for SCs 21-22 and 19-23, respectively, and they are also utilized to get estimates of the Shannon entropy. It is found that the Shannon entropy, a measure of randomness inherent in the SC, is reflected well in the various proxies of the solar activity (viz sunspot, magnetic field, F10.7 flux). The applicability and accuracy of the prediction model equation is verified by way of association of least entropy values with the Dalton minimum. The prediction model equation also provides possible criteria for the occurrence of unusually longer solar minima.

  9. Towards better constrained models of the solar magnetic cycle

    NASA Astrophysics Data System (ADS)

    Munoz-Jaramillo, Andres

    2010-12-01

    The best tools we have for understanding the origin of solar magnetic variability are kinematic dynamo models. During the last decade, this type of models has seen a continuous evolution and has become increasingly successful at reproducing solar cycle characteristics. The basic ingredients of these models are: the solar differential rotation -- which acts as the main source of energy for the system by shearing the magnetic field; the meridional circulation -- which plays a crucial role in magnetic field transport; the turbulent diffusivity -- which attempts to capture the effect of convective turbulence on the large scale magnetic field; and the poloidal field source -- which closes the cycle by regenerating the poloidal magnetic field. However, most of these ingredients remain poorly constrained which allows one to obtain solar-like solutions by "tuning" the input parameters, leading to controversy regarding which parameter set is more appropriate. In this thesis we revisit each of those ingredients in an attempt to constrain them better by using observational data and theoretical considerations, reducing the amount of free parameters in the model. For the meridional flow and differential rotation we use helioseismic data to constrain free parameters and find that the differential rotation is well determined, but the available data can only constrain the latitudinal dependence of the meridional flow. For the turbulent magnetic diffusivity we show that combining mixing-length theory estimates with magnetic quenching allows us to obtain viable magnetic cycles and that the commonly used diffusivity profiles can be understood as a spatiotemporal average of this process. For the poloidal source we introduce a more realistic way of modeling active region emergence and decay and find that this resolves existing discrepancies between kinematic dynamo models and surface flux transport simulations. We also study the physical mechanisms behind the unusually long minimum of

  10. 27-day solar cycle signature in NLC occurrence rates

    NASA Astrophysics Data System (ADS)

    Robert, Charles; von Savigny, Christian; Burrows, John P.; Deland, Matthew

    Noctilucent clouds (NLC) are optically thin layered phenomena which are usually observed at an altitude of about 83 km during the summer season at latitudes polewards of 55° . They are made of water ice particles, the size of which is estimated to be generally smaller than 100 nm. They exist as the consequence of the cold and humid upper mesosphere at high latitudes during the summer season, and are believed to be extremely sensitive to both temperature and water vapor content. As a consequence, they are often perceived as possible early indicators of global change. Satellite measurements provide global measurements of NLC and contribute significantly to our understanding of their behavior. Although the main features of the seasonal change of NLC occurrence rates are now established, variations of NLC activity on shorter timescale are not so well understood. It was shown that dynamical processes such as planetary waves, gravity waves and atmospheric tides can affect NLC, mainly through temperature alteration. Other processes can influence NLC, such as solar-proton event and possibly lunar cycle. It was also shown that on longer timescales, NLC are affected by the 11-year solar cycle. Using SCIAMACHY and SBUV/2 satellite measurements, we present here evidence that the occurrence rates of NLC exhibit a 27-day cycle. This variation seems to be correlated with the solar lyman-alpha flux, especially during years of stronger solar activity. MLS mesospheric water vapor and temperature available during some of the NLC season will be presented alongside in order to better understand the connection between the different processes. Possible physical mechanisms are discussed.

  11. Solar cycle and diurnal dependence of auroral structures

    NASA Astrophysics Data System (ADS)

    Partamies, N.; Whiter, D.; Syrjäsuo, M.; Kauristie, K.

    2014-10-01

    In order to facilitate usage of optical data in space climate studies, we have developed an automated algorithm to quantify the complexity of auroral structures as they appear in ground-based all-sky images. The image analysis is based on a computationally determined "arciness" value, which describes how arc like the auroral structures in the image are. With this new automatic method we have analyzed the type of aurora in about 1 million images of green aurora (λ = 557.7nm) captured at five camera stations in Finnish and Swedish Lapland in 1996-2007. We found that highly arc like structures can be observed in any time sector and their portion of the auroral structures varies much less than the fraction of more complex forms. The diurnal distribution of arciness is in agreement with an earlier study with high arc occurrence rate in the evening hours and steadily decreasing toward the late morning hours. The evolution of less arc-like auroral structures is more dependent on the level of geomagnetic activity and solar cycle than the occurrence of arcs. The median arciness is higher during the years close to the solar minimum than during the rest of the solar cycle. Unlike earlier proposed, the occurrence rate of both arcs and more complex auroral structures increases toward the solar maximum and decreases toward the solar minimum. The cyclic behavior of auroral structures seen in our data is much more systematic and clear than previously reported visual studies suggest. The continuous arciness index describing the complexity of auroral structures can improve our understanding on auroral morphology beyond the few commonly accepted structure classes, such as arcs, patches, and omega bands. Arciness can further be used to study the relationship of auroral structures at different complexity levels and magnetospheric dynamics.

  12. A physical mechanism for the prediction of the sunspot number during solar cycle 21. [graphs (charts)

    NASA Technical Reports Server (NTRS)

    Schatten, K. H.; Scherrer, P. H.; Svalgaard, L.; Wilcox, J. M.

    1978-01-01

    On physical grounds it is suggested that the sun's polar field strength near a solar minimum is closely related to the following cycle's solar activity. Four methods of estimating the sun's polar magnetic field strength near solar minimum are employed to provide an estimate of cycle 21's yearly mean sunspot number at solar maximum of 140 plus or minus 20. This estimate is considered to be a first order attempt to predict the cycle's activity using one parameter of physical importance.

  13. Sources of the Slow Solar Wind During the Solar Cycle 23/24 Minimum

    NASA Astrophysics Data System (ADS)

    Kilpua, E. K. J.; Madjarska, M. S.; Karna, N.; Wiegelmann, T.; Farrugia, C.; Yu, W.; Andreeova, K.

    2016-10-01

    We investigate the characteristics and the sources of the slow ({<} 450 km s^{-1}) solar wind during the four years (2006 - 2009) of low solar activity between Solar Cycles 23 and 24. We used a comprehensive set of in-situ observations in the near-Earth solar wind ( Wind and ACE) and removed the periods when large-scale interplanetary coronal mass ejections were present. The investigated period features significant variations in the global coronal structure, including the frequent presence of low-latitude active regions in 2006 - 2007, long-lived low- and mid-latitude coronal holes in 2006 - mid-2008 and mostly the quiet Sun in 2009. We examined Carrington rotation averages of selected solar plasma, charge state, and compositional parameters and distributions of these parameters related to the quiet Sun, active region Sun, and the coronal hole Sun. While some of the investigated parameters ( e.g. speed, the C+6/C+4 and He/H ratios) show clear variations over our study period and with solar wind source type, some (Fe/O) exhibit very little changes. Our results highlight the difficulty of distinguishing between the slow solar wind sources based on the inspection of solar wind conditions.

  14. Sources of the Slow Solar Wind During the Solar Cycle 23/24 Minimum

    NASA Astrophysics Data System (ADS)

    Kilpua, E. K. J.; Madjarska, M. S.; Karna, N.; Wiegelmann, T.; Farrugia, C.; Yu, W.; Andreeova, K.

    2016-09-01

    We investigate the characteristics and the sources of the slow ( {<} 450 km s^{-1}) solar wind during the four years (2006 - 2009) of low solar activity between Solar Cycles 23 and 24. We used a comprehensive set of in-situ observations in the near-Earth solar wind (Wind and ACE) and removed the periods when large-scale interplanetary coronal mass ejections were present. The investigated period features significant variations in the global coronal structure, including the frequent presence of low-latitude active regions in 2006 - 2007, long-lived low- and mid-latitude coronal holes in 2006 - mid-2008 and mostly the quiet Sun in 2009. We examined Carrington rotation averages of selected solar plasma, charge state, and compositional parameters and distributions of these parameters related to the quiet Sun, active region Sun, and the coronal hole Sun. While some of the investigated parameters (e.g. speed, the C+6/C+4 and He/H ratios) show clear variations over our study period and with solar wind source type, some (Fe/O) exhibit very little changes. Our results highlight the difficulty of distinguishing between the slow solar wind sources based on the inspection of solar wind conditions.

  15. Solar cycles or random processes? Evaluating solar variability in Holocene climate records

    PubMed Central

    Turner, T. Edward; Swindles, Graeme T.; Charman, Dan J.; Langdon, Peter G.; Morris, Paul J.; Booth, Robert K.; Parry, Lauren E.; Nichols, Jonathan E.

    2016-01-01

    Many studies have reported evidence for solar-forcing of Holocene climate change across a range of archives. These studies have compared proxy-climate data with records of solar variability (e.g. 14C or 10Be), or have used time series analysis to test for the presence of solar-type cycles. This has led to some climate sceptics misrepresenting this literature to argue strongly that solar variability drove the rapid global temperature increase of the twentieth century. As proxy records underpin our understanding of the long-term processes governing climate, they need to be evaluated thoroughly. The peatland archive has become a prominent line of evidence for solar forcing of climate. Here we examine high-resolution peatland proxy climate data to determine whether solar signals are present. We find a wide range of significant periodicities similar to those in records of solar variability: periods between 40–100 years, and 120–140 years are particularly common. However, periodicities similar to those in the data are commonly found in random-walk simulations. Our results demonstrate that solar-type signals can be the product of random variations alone, and that a more critical approach is required for their robust interpretation. PMID:27045989

  16. Solar cycles or random processes? Evaluating solar variability in Holocene climate records.

    PubMed

    Turner, T Edward; Swindles, Graeme T; Charman, Dan J; Langdon, Peter G; Morris, Paul J; Booth, Robert K; Parry, Lauren E; Nichols, Jonathan E

    2016-04-05

    Many studies have reported evidence for solar-forcing of Holocene climate change across a range of archives. These studies have compared proxy-climate data with records of solar variability (e.g. (14)C or (10)Be), or have used time series analysis to test for the presence of solar-type cycles. This has led to some climate sceptics misrepresenting this literature to argue strongly that solar variability drove the rapid global temperature increase of the twentieth century. As proxy records underpin our understanding of the long-term processes governing climate, they need to be evaluated thoroughly. The peatland archive has become a prominent line of evidence for solar forcing of climate. Here we examine high-resolution peatland proxy climate data to determine whether solar signals are present. We find a wide range of significant periodicities similar to those in records of solar variability: periods between 40-100 years, and 120-140 years are particularly common. However, periodicities similar to those in the data are commonly found in random-walk simulations. Our results demonstrate that solar-type signals can be the product of random variations alone, and that a more critical approach is required for their robust interpretation.

  17. Auroral electrojets during deep solar minimum at the end of solar cycle 23

    NASA Astrophysics Data System (ADS)

    Pulkkinen, T. I.; Tanskanen, E. I.; Viljanen, A.; Partamies, N.; Kauristie, K.

    2011-04-01

    We investigate the auroral electrojet activity during the deep minimum at the end of solar cycle 23 (2008-2009) by comparing data from the IMAGE magnetometer chain, auroral observations in Fennoscandia and Svalbard, and solar wind and interplanetary magnetic field (IMF) observations from the OMNI database from that period with those recorded one solar cycle earlier. We examine the eastward and westward electrojets and the midnight sector separately. The electrojets during 2008-2009 were found to be weaker and at more poleward latitudes than during other times, but when similar driving solar wind and IMF conditions are compared, the behavior in the morning and evening sectors during 2008-2009 was similar to other periods. On the other hand, the midnight sector shows distinct behavior during 2008-2009: for similar driving conditions, the electrojets resided at further poleward latitudes and on average were weaker than during other periods. Furthermore, the substorm occurrence frequency seemed to saturate to a minimum level for very low levels of driving during 2009. This analysis suggests that the solar wind coupling to the ionosphere during 2008-2009 was similar to other periods but that the magnetosphere-ionosphere coupling has features that are unique to this period of very low solar activity.

  18. Galactic and solar radiation exposure to aircrew during a solar cycle.

    PubMed

    Lewis, B J; Bennett, L G I; Green, A R; McCall, M J; Ellaschuk, B; Butler, A; Pierre, M

    2002-01-01

    An on-going investigation using a tissue-equivalent proportional counter (TEPC) has been carried out to measure the ambient dose equivalent rate of the cosmic radiation exposure of aircrew during a solar cycle. A semi-empirical model has been derived from these data to allow for the interpolation of the dose rate for any global position. The model has been extended to an altitude of up to 32 km with further measurements made on board aircraft and several balloon flights. The effects of changing solar modulation during the solar cycle are characterised by correlating the dose rate data to different solar potential models. Through integration of the dose-rate function over a great circle flight path or between given waypoints, a Predictive Code for Aircrew Radiation Exposure (PCAIRE) has been further developed for estimation of the route dose from galactic cosmic radiation exposure. This estimate is provided in units of ambient dose equivalent as well as effective dose, based on E/H x (10) scaling functions as determined from transport code calculations with LUIN and FLUKA. This experimentally based treatment has also been compared with the CARI-6 and EPCARD codes that are derived solely from theoretical transport calculations. Using TEPC measurements taken aboard the International Space Station, ground based neutron monitoring, GOES satellite data and transport code analysis, an empirical model has been further proposed for estimation of aircrew exposure during solar particle events. This model has been compared to results obtained during recent solar flare events.

  19. Observations of hysteresis in solar cycle variations among seven solar activity indicators

    NASA Technical Reports Server (NTRS)

    Bachmann, Kurt T.; White, Oran R.

    1994-01-01

    We show that smoothed time series of 7 indices of solar activity exhibit significant solar cycle dependent differences in their relative variations during the past 20 years. In some cases these observed hysteresis patterns start to repeat over more than one solar cycle, giving evidence that this is a normal feature of solar variability. Among the indices we study, we find that the hysteresis effects are approximately simple phase shifts, and we quantify these phase shifts in terms of lag times behind the leading index, the International Sunspot Number. Our measured lag times range from less than one month to greater than four months and can be much larger than lag times estimated from short-term variations of these same activity indices during the emergence and decay of major active regions. We argue that hysteresis represents a real delay in the onset and decline of solar activity and is an important clue in the search for physical processes responsible for changing solar emission at various wavelengths.

  20. The solar cycle dependence of the location and shape of the Venus bow shock

    NASA Technical Reports Server (NTRS)

    Zhang, T.-L.; Luhmann, J. G.; Russell, C. T.

    1990-01-01

    The Venus terminator bow shock position is monitored and it is shown that the shock radius increases as the solar cycle approaches a new maximum. It is also shown that the subsolar bow shock changes with the solar cycle, and that these positions are correlated with each other and with solar activity. It is hypothesized that, at solar minimum, the magnetic barrier is weak, and that some absorption of solar wind is to be expected.

  1. The "Approximate 150 Day Quasi-Periodicity" in Interplanetary and Solar Phenomena During Cycle 23

    NASA Technical Reports Server (NTRS)

    Richardson, I. G.; Cane, H. V.

    2004-01-01

    A"quasi-periodicity" of approx. 150 days in various solar and interplanetary phenomena has been reported in earlier solar cycles. We suggest that variations in the occurrence of solar energetic particle events, inter-planetary coronal mass ejections, and geomagnetic storm sudden commenceents during solar cycle 23 show evidence of this quasi-periodicity, which is also present in the sunspot number, in particular in the northern solar hemisphere. It is not, however, prominent in the interplanetary magnetic field strength.

  2. Solar Cycle Variability in New Merge Satellite Ozone Datasets

    NASA Astrophysics Data System (ADS)

    Kuchar, A.; Pisoft, P.

    2014-12-01

    Studies using coupled chemistry climate model simulations of the solar cycle in the ozone field reveal agreement with the observed "double-peaked" ozone anomaly in the original satellite observations represented by SBUV(/2), HALOE and SAGE datasets. The motivation of our analysis is to examine whether the solar signal in the last generation of reanalyzed datasets (i.e. MERRA and ERA-INTERIM) is consistent with the observed double-peaked ozone anomaly extracted from satellite measurements. Since an analysis of the solar cycle response requires long-term and temporal homogeneous time series of the ozone profile and no single satellite instrument has covered the entire period since 1984, satellite measurements in our study are represented by new merged satellite ozone datasets, i.e. GOZCARDS, SBUV MOD and SWOOSH datasets. The results of the presented study are based on the attribution analysis using multiple nonlinear techniques besides traditional linear approach based on the multiple linear models. The study results are supplemented by a frequency analysis using the pseudo-2D wavelet transform algorithms.

  3. Solar wind and coronal rotation during an activity cycle

    NASA Astrophysics Data System (ADS)

    Pinto, Rui; Brun, Allan Sacha

    The properties of the solar wind flow are strongly affected by the time-varying strength and geometry of the global background magnetic field. The wind velocity and mass flux depend directly on the size and position of the wind sources at the surface, and on the geometry of the magnetic flux-tubes along which the wind flows. We address these problems by performing numerical simulations coupling a kinematic dynamo code (STELEM) evolve in a 2.5D axisymmetric coronal MHD code (DIP) covering an 11 yr activity cycle. The latitudinal distribution of the calculated wind velocities agrees with in-situ (ULYSSES, HELIO) and radio measurements (IPS). The transition from fast to slow wind flows can be explained in terms of the high overall flux-tube superradial expansion factors in the vicinities of coronal streamer boundaries. We found that the Alfvén radii and the global Sun's mass loss rate vary considerably throughout the cycle (by a factor 4.5 and 1.6, respectively), leading to strong temporal modulations of the global angular momentum flux and magnetic braking torque. The slowly varying magnetic topology introduces strong non-uniformities in the coronal rotation rate in the first few solar radii. Finally, we point out directions to assess the effects of surface transient phenomena on the global properties of the solar wind.

  4. Solar-Cycle Evolution of Subsurface Flows and Magnetic Field

    NASA Astrophysics Data System (ADS)

    Kosovichev, Alexander G.; Zhao, Junwei

    2016-05-01

    Local helioseismology and magnetic field measurements from the HMI instrument on SDO provide unique high-resolution data that allow us to investigate detailed dynamics of the upper convection zone and its relation to the magnetic field evolution during the first five years of the current solar cycle. This study is focused on the understanding the role of the near-surface shear layer (NSSL) in the dynamo process, generation, emergence and transport of the solar magnetic flux. The helioseismology data represent 3D flow maps in the depth range of 0-20 Mm, obtained uninterruptedly every 8 hours for almost the whole solar disk with the spatial sampling of two arcsec. We calculate the flow characteristics (such as divergence, vorticity and kinetic helicity) on different spatio-temporal scales from supergranulation to global-scale zonal and meridional flows. We investigate the multi-scale organization of the subsurface flows, including the inflows into active regions, the hemispheric `flip-flop’ asymmetry of variations of the meridional flows, the structure and dynamics of torsional oscillations, and compare the flow behavior with the evolution of the observed magnetic activity of the current cycle.

  5. EDITORIAL: The 19th MicroMechanics Europe Workshop (MME 2008) The 19th MicroMechanics Europe Workshop (MME 2008)

    NASA Astrophysics Data System (ADS)

    Schnakenberg, Uwe

    2009-07-01

    This special issue of Journal of Micromechanics and Microengineering is devoted to the 19th MicroMechanics Europe Workshop (MME 08), which took place at the RWTH Aachen University, Aachen, Germany, from 28-30 September, 2008. The workshop is a well recognized and established European event in the field of micro system technology using thin-film technologies for creating micro components, micro sensors, micro actuators, and micro systems. The first MME Workshop was held 1989 in Enschede (The Netherlands) and continued 1990 in Berlin (Germany), 1992 in Leuven (Belgium), and then was held annually in Neuchâtel (Switzerland), Pisa (Italy), Copenhagen (Denmark), Barcelona (Spain), Southampton (UK), Ulvik in Hardanger (Norway), Gif-sur-Yvette (France), Uppsala (Sweden), Cork (Ireland), Sinaia (Romania), Delft (The Netherlands), Leuven (Belgium), Göteborg (Sweden), Southampton (UK), and in Guimarães (Portugal). The two day workshop was attended by 180 delegates from 26 countries all over Europe and from Armenia, Austria, Bulgaria, Canada, China, Cuba, Iran, Japan, Korea, Malaysia, Taiwan, Turkey, and the United States of America. A total of 97 papers were accepted for presentation and there were a further five keynote presentations. I am proud to present 22 high-quality papers from MME 2008 selected for their novelty and relevance to Journal of Micromechanics and Microengineering. All the papers went through the regular reviewing procedure of IOP Publishing. I am eternally grateful to all the referees for their excellent work. I would also like to extend my thanks to the members of the Programme Committee of MME 2008, Dr Reinoud Wolffenbuttel, Professor José Higino Correia, and Dr Patrick Pons for pre-selection of the papers as well as to Professor Robert Puers for advice on the final selection of papers. My thanks also go to Dr Ian Forbes of IOP Publishing for managing the entire process and to the editorial staff of Journal of Micromechanics and Microengineering. I

  6. Paleoradiology of the Savoca Mummies, Sicily, Italy (18th-19th Centuries AD).

    PubMed

    Piombino-Mascali, Dario; Jankauskas, Rimantas; Zink, Albert R; Sergio Todesco, M; Aufderheide, Arthur C; Panzer, Stephanie

    2015-06-01

    Mummified remains have been successfully studied radiologically since the end of the 19th century, giving rise to a specific field of research-paleoradiology. In this paper, we present the results of the first radiological investigation of a collection of Sicilian mummies found in a subterranean chamber beneath the Capuchin Church of Savoca. The chamber contains a number of preserved bodies, either held in special niches in the walls or interred within coffins. A recent detailed radiological examination of these mummies allowed the authors to determine information relating to the funerary treatment and some of the pathological alterations witnessed in the remains. Specifically, evidence of gout and DISH was identified, along with frequent degenerative joint disease, suggestive of rich dietary habits and a longer life expectancy. These findings were interpreted in the light of historical information and the social status of the subjects concerned.

  7. [Healthcare in times of epidemics in Rio de Janeiro in the 19th century].

    PubMed

    Pimenta, Tânia Salgado

    2011-01-01

    This article aims to examine the provision of healthcare for the population of Rio de Janeiro in the mid-19th century and describe its reorganization during the crisis caused by outbreaks of yellow fever and cholera. In this context, it is essential to consider the significant changes taking place in healthcare during this period, also affecting the spaces in which hospital care was offered. Therefore, we focussed our investigation on Santa Casa da Misericórdia Hospital, the most important hospital in the capital of the Brazilian Empire. The sources used are the correspondence between the government and the hospital, the hospital annual reports, archives of the Central Board of Public Hygiene, and wide-circulation medical journals.

  8. [The art of improvising. The practice of medico-legal autopsies in the 19th century].

    PubMed

    Menenteau, Sandra

    2012-01-01

    Murder is perpetrated, suicide is committed and lethal accidents happen everywhere, even in the heart of the French country. In the 19th century, law often appealed to the lights of experts. During criminal investigation, improvisation and men's adaptation were important, although forensic autopsy was official and necessary. Sometimes the magistrates appealed to young people, not used to that kind of reports, who could only remind some bits of the forensic courses they had followed when they were students. As for the specialists, the circumstances often led them to examine--as Baudelaire would say--the "decaying carcass," in a dark and suffocating ruined house, on the kitchen table, and with a simple scapel.

  9. JP Morgan Hambrecht & Quist - 19th Annual Healthcare Conference. Gilead Sciences, American Home Products and Curis.

    PubMed

    Hookes, J

    2001-03-01

    The 19th Annual JP Morgan H and Q Healthcare Conference provided yet another fascinating opportunity to meet with, and hear presentations by, a number of representatives of wellestablished Big Pharma companies, biotech start-up companies and the healthcare service and healthcare 'dot.com' industries. The conference was hosted by JP Morgan H and Q, part of the newly formed JP Morgan - the wholesale banking group of JP Morgan Chase and Co - which led-managed 13 IPOs in the healthcare industry in 2000. This year, the conference was attended by over 5000 delegates, and in excess of 270 company presentations in six parallel sessions were made to members of the healthcare industries, the media and the investment community. PMID:16025374

  10. Mortality differentials in France during the late 18th and early 19th centuries.

    PubMed

    Blum, A; Houdaille, J; Lamouche, M

    1990-01-01

    "The very high quality of a set of marriage records for Paris during the 1860s made it possible to apply indirect methods to estimate adult mortality differentials by certain geographical and social criteria of the 19th century. The largest differences between groups were observed to be social, geographical origin apparently having little impact.... It is interesting that social differences in adult mortality are similar in magnitude to those observed today. Perhaps the principal factor of differentiation is then the level of child mortality.... It is by no means necessary to have a set of data as complete as ours. The indirect methods we have used proved largely adequate for estimating mortality differentials."

  11. Following rules in the intermontane west: 19th-century mormon settlement

    PubMed Central

    Norton, William

    2001-01-01

    The academic discipline of human geography is concerned with human activities, especially as these relate to physical landscapes and contribute to the modification of those landscapes. Although little attention has been paid to objectivist philosophies to inform human geography, behavior analysis might offer a useful explanatory model. As an example, a behavior analysis of selected aspects of 19th-century Mormon movement and settlement in the intermontane West is conducted. Mormons are a society of believers who practice cooperative effort and support for other members, and the Mormon church is governed by priesthood authority with members being called to perform tasks. This analysis employs the concepts of metacontingency, rule-governed behavior, and delayed reinforcement to analyze how Mormons settled the intermontane West. PMID:22478355

  12. Epilepsy and insanity during the early 19th century. A conceptual history.

    PubMed

    Berrios, G E

    1984-09-01

    During the first half of the 19th century, epilepsy and the insanities were considered as closely related "neurotic" disorders. Under the influence of factors such as the decline of the 18th-century Cullean concept of neurosis, the development of the new descriptive psychopathology, the introduction of statistics, and the availability of longitudinal observations of hospitalized cohorts, epilepsy was redefined as a "neurological" disease by the 1850s. The reaction of psychiatry to the exclusion of the mental disorder as a defining feature of epilepsy manifested itself in the creation of the "masked epilepsy" concept. This notion is behind the later development of categories such as "borderland" and "equivalent," which are still of some relevance to 20th-century views of epilepsy.

  13. Height of female Americans in the 19th century and the antebellum puzzle.

    PubMed

    Carson, Scott Alan

    2011-03-01

    Using 19th century state prison records, this study contrasts the biological standard of living of comparable US African-American and white females during a period of relatively rapid economic development. White females were consistently taller than black females by about 1.5 cm (0.6 in.). Whites from Great Lakes and Plains states and black Southwestern females were the tallest. US females were tall compared to their European counterparts. The height of females began to decline in the antebellum period, possibly before that of males. The recovery of physical stature was also earlier among females than among males. This implies that the biological standard of lower-class men and women did not move in parallel during the onset of modern economic growth. It also implies that the antebellum puzzle was most likely rooted in the endogenous forces of socio-economic change rather than the exogenous changes in the disease environment.

  14. Paths to and from poverty in late 19th century novels

    PubMed Central

    Howden‐Chapman, Philippa; Kawachi, Ichiro

    2006-01-01

    Late 19th century novels provide graphic descriptions of working and living conditions and their impact on population health, in particular the detrimental effects of hunger, poor housing, environmental conditions, hazardous work and poor pay, smoking and alcohol and crime, but also the transformative possibilities of social and political action. The popularity of these novels helped raise the collective conscience of citizens and illuminated the direction for 20th century welfare reforms. Yet many of these problems remain and the pathways to and from poverty are still recognisable today. Although novels are now less central in conveying social information, re‐reading these novels enables us to understand how social and economic circumstances were understood at the time and what led to social and political change. PMID:16415257

  15. Jean-Louis Brachet (1789-1858). A forgotten contributor to early 19th century neurology.

    PubMed

    Walusinski, O

    2015-10-01

    Specialists of the history of hysteria know the name of Jean-Louis Brachet (1789-1858), but few realise the influence of this physician and surgeon from Lyon, a city in the southeastern part of France. Not only a clinician, he was also a neurophysiology researcher in the early 19th century. Along with his descriptions of meningoencephalitis, including hydrocephalus and meningoencephalitis, he elucidated the functioning of the vegetative nervous system and described its activity during emotional states. He also helped describe the different forms of epilepsy and sought to understand their aetiologies, working at the same time as the better-known Louis-Florentin Calmeil (1798-1895). We present a biography of this forgotten physician, a prolific writer, keen clinical observer and staunch devotee of a rigorous scientific approach.

  16. [Crespi d'Adda: psychosocial risk factors in a late 19th century company town].

    PubMed

    Punzi, S

    2012-01-01

    Crespi d'Adda is a late 19th century company town established around a textile factory by Cristoforo Benigno Crespi and his son Silvio. It was an ideal model of company residency being a self-sufficient microcosm equipped with all the services needed by a community where the life of workers and their families was revolving around the factory and the working requirements. It was the expression of philanthropic and patronizing enlightened entrepreneurs at that time, committed in protecting workers' life inside and outside the factory, resulting into a more affectionate and productive manpower. Silvio Benigno Crespi developed an extensive activity to improve working conditions, with special reference to accident prevention and work-related diseases, as well as night work in factories, weekly day off, reduction of working hours: we can say that in some ways he was concerned also with psychosocial risks. PMID:23405777

  17. [Outer form and internal disease: clinical photography in the late 19th century].

    PubMed

    Kröner, Hans-Peter

    2005-06-01

    Clinical photography in the late 19th century aimed at unveiling the hidden processes invisible to the clinical eye. Changes in the outer form hinted at deeper lying causes, and decoding these forms was supposed to extend the range of the clinical eye in to the realm of invisibility. Two suppositions supported this hope: the belief that each disease as an ontological entity showed typical exterior signs which allowed a diagnosis at sight, and the technological trust in photography as a precise and objective means of representation superior to the human eye. For a short time, clinical photography seemed to be the 'via regia" of diagnosis. Heinrich Curschmann's Klinische Abbildungen and Ludwig Jankau's periodical Internationale medizinisch-photographische Monatsschrift marked the climax of this development in Germany. Röntgen's discovery and its immediate application in clinical medicine put an end to the optimistic expectations: clinical photography was from now on only one among many different means of documenting clinical signs and findings.

  18. Apothecary activity in Dubrovnik Dominican Monastery from 17th to the beginning 19th century.

    PubMed

    Krasic, Stjepan

    2011-01-01

    The origin of the Dominican monastery pharmacy is not clear, but sources suggest that it had operated from the eve of the great earthquake in Dubrovnik in 1667 to the beginning of the 19th century. Its last pharmacist, praised for his competence, passed away in 1803, leaving no one behind The prior travelled all the way to Naples to find a competent pharmacist in his stead, but never returned. Story has it that on the way back, the abbot and the pharmacist lost their lives in a shipwreck. The French army occupied the town in 1806, and the monastery was turned into a military camp. Following the retreat of the French army in 1814, the monastery was returned to the Dominicans, but the pharmacy was never restored. PMID:22047479

  19. Placenta Accreta and Total Placenta Previa in the 19th Week of Pregnancy

    PubMed Central

    Findeklee, S.; Costa, S. D.

    2015-01-01

    Placentation disorders are the result of impaired embedding of the placenta in the endometrium. The prevalence of these disorders is estimated to be around 0.3 %. A history of previous prior uterine surgery (especially cesarean section and curettage) is the most common risk factor. Impaired placentation is differentiated into deep placental attachment; marginal, partial and total placenta previa; and placenta accreta, increta and percreta. Treatment depends on the severity of presentation and ranges from expectant management to emergency hysterectomy. In most cases, preterm termination of pregnancy is necessary. We report here on the case of a 39-year-old woman with placenta accreta and total placenta previa who underwent hysterectomy in the 19th week of pregnancy. PMID:26366004

  20. Height of female Americans in the 19th century and the antebellum puzzle.

    PubMed

    Carson, Scott Alan

    2011-03-01

    Using 19th century state prison records, this study contrasts the biological standard of living of comparable US African-American and white females during a period of relatively rapid economic development. White females were consistently taller than black females by about 1.5 cm (0.6 in.). Whites from Great Lakes and Plains states and black Southwestern females were the tallest. US females were tall compared to their European counterparts. The height of females began to decline in the antebellum period, possibly before that of males. The recovery of physical stature was also earlier among females than among males. This implies that the biological standard of lower-class men and women did not move in parallel during the onset of modern economic growth. It also implies that the antebellum puzzle was most likely rooted in the endogenous forces of socio-economic change rather than the exogenous changes in the disease environment. PMID:21276759

  1. [Significance of cognitive processes in drug research in the 19th century--exemplified by nitroglycerin].

    PubMed

    Schüppel, R

    1997-01-01

    The history of the discovery and development of drugs is replete with examples where chance and "serendipity" have resulted in important advances of knowledge. In the case of nitroglycerin it can be shown that what appears to have been a chance discovery was actually the result of a sequence of selective perceptions by, and cognitive processes in individual researchers. The sources allow insight into various stages of the development of nitroglycerin, starting with the chemical synthesis as an explosive in 1846 and the first use in humans in 1847 to the discovery of a useful coronary drug. Homeopathic medicine contributed significantly to this process. Thus, the history of nitroglycerin is an example of an exchange of knowledge between otherwise separate realms of sectarian and orthodox medicine in the second half of the 19th century.

  2. Human lead exposure in a late 19th century mental asylum population.

    PubMed

    Bower, Nathan W; McCants, Sarah A; Custodio, Joseph M; Ketterer, Michael E; Getty, Stephen R; Hoffman, J Michael

    2007-01-01

    Lead isotope ratios and lead (Pb) levels were analyzed in 33 individuals from a forgotten cemetery at the Colorado Mental Health Institute at Pueblo, Colorado dating to 1879-1899. Isotopic ratios from healing bone fractures, cortical bone, and tooth dentine provide information about sources of Pb exposures over a range of time that illuminates individual's life histories and migration patterns. Historical records and Pb production data from the 19th century were used to create a database for interpreting Pb exposures for these African, Hispanic and European Americans. The analysis of these individuals suggests that Pb exposure noticeably impacted the mental health of 5-10% of the asylum patients in this frontier population, a high number by standards today, and that differences exist in the three ancestral groups' exposure histories.

  3. [Knud Faber and the Paris medicine in the 19th century].

    PubMed

    Jensen, Niels Kristoffer

    2007-01-01

    The socalled "Paris medicine" in the beginning of the 19th century initiated by the French revolution has always been regarded as something special and of great importance for the development in the medical field and this period has attracted many authors and historians for interpretation. Foucault and Ackerknecht are the latest authors that have given an estimation. A need, however, was felt for a new reinterpretation. The papers of a conference at the College of Physicians in 1992 was published in The Wellcome Institute Series in the History of Medicine in 1998 under the name of "Constructing Paris Medicine" that should elucidate the problem. In Denmark we have a rather early estimation due to professor Knud Fabers book from 1919, which was translated into English in 1923 and 1930.

  4. Solar Thermochemical Fuels Production: Solar Fuels via Partial Redox Cycles with Heat Recovery

    SciTech Connect

    2011-12-19

    HEATS Project: The University of Minnesota is developing a solar thermochemical reactor that will efficiently produce fuel from sunlight, using solar energy to produce heat to break chemical bonds. The University of Minnesota is envisioning producing the fuel by using partial redox cycles and ceria-based reactive materials. The team will achieve unprecedented solar-to-fuel conversion efficiencies of more than 10% (where current state-of-the-art efficiency is 1%) by combined efforts and innovations in material development, and reactor design with effective heat recovery mechanisms and demonstration. This new technology will allow for the effective use of vast domestic solar resources to produce precursors to synthetic fuels that could replace gasoline.

  5. A chaotic model for the plague epidemic that has occurred in Bombay at the end of the 19th century

    NASA Astrophysics Data System (ADS)

    Mangiarotti, Sylvain

    2015-04-01

    The plague epidemic that has occurred in Bombay at the end of the 19th century was detected in 1896. One year before, an Advisory Committee had been appointed by the Secretary of State for India, the Royal Society, and the Lister Institute. This Committee made numerous investigations and gathered a large panel of data including the number of people attacked and died from the plague, records of rat and flea populations, as well as meteorological records of temperature and humidity [1]. The global modeling technique [2] aims to obtain low dimensional models able to simulate the observed cycles from time series. As far as we know, this technique has been tried only to one case of epidemiological analysis (the whooping cough infection) based on a discrete formulation [3]. In the present work, the continuous time formulation of this technique is used to analyze the time evolution of the plague epidemic from this data set. One low dimensional model (three variables) is obtained exhibiting a limit cycle of period-5. A chaotic behavior could be derived from this model by tuning the model parameters. It provides a strong argument for a dynamical behavior that can be approximated by low dimensional deterministic equations. This model also provides an empirical argument for chaos in epidemics. [1] Verjbitski D. T., Bannerman W. B. & Kápadiâ R. T., 1908. Reports on Plague Investigations in India (May,1908), The Journal of Hygiene, 8(2), 161 -308. [2] Mangiarotti S., Coudret R., Drapeau L. & Jarlan L., 2012. Polynomial search and Global modelling: two algorithms for modeling chaos. Physical Review E, 86(4), 046205. [3] Boudjema G. & Cazelles B., 2003. Extraction of nonlinear dynamics from short and noisy time series. Chaos, Solitons and Fractals, 12, 2051-2069.

  6. Reconstructions of global near-surface temperature change since the mid 19th century

    NASA Astrophysics Data System (ADS)

    Morice, Colin; Rayner, Nick; Kennedy, John

    2016-04-01

    Incomplete and non-uniform global observational coverage is a prominent source of uncertainty in instrumental records of global near-surface temperature change. In this study statistical methods are applied to the HadCRUT4 near-surface temperature data set to obtain improved estimates of global near-surface temperature change since the mid 19th century. Methods applied include those that interpolate according to local correlation structure (kriging) and reduced space methods that learn large-scale temperature patterns. The performance of each statistical reconstruction method has been benchmarked in application to a subset of CMIP5 simulations. Model fields are sub-sampled and simulated observational errors added to emulate observational data, permitting assessment of temperature field reconstruction algorithms in controlled tests in which globally complete temperature fields are known. In application to HadCRUT4 data the statistical reconstructions show relatively increased warming in the global average over the 21st century owing to reconstruction of temperatures in high northern latitudes, supporting the findings of Cowtan & Way (2014) and Karl et al. (2015). There is broad agreement between estimates of global and hemispheric changes throughout much of the 20th and 21st century. Agreement is reduced in data sparse periods and regions, notably in the 19th century and in the southern hemisphere. This finding is supported by the results of the climate model based benchmarks and highlights the importance of continued data rescue activities, such as those of the International Surface Temperature Initiative and ACRE. The results of this study will form an addition to the HadCRUT4 global near-surface temperature data set.

  7. Science Fiction In Naples In The Middle Of The 19th Century

    NASA Astrophysics Data System (ADS)

    Capaccioli, Massimo; Cirella, Emilia Olostro; Stendardo, Enrica; Virgilio, Nicla

    Astronomer, intellectual, passionate patriot, and refined humanist, Ernesto Capocci Belmonte (Picinisco, May 31, 1798 - Naples, January 6, 1864) was a prominent figure of the scientific, cultural, and political life in Naples around the middle of the 19th century. He acquired international recognition for his studies on the orbits of comets and, since 1833, he was named director of the newly built Osservatorio Astronomico in Capodimonte: A prestigious position that he lost for political retaliation as a result of his participation in the movement against the Bourbon rulers in 1848, but which he regained in 1860 upon the arrival in Naples of Giuseppe Garibaldi. An intuitive and open-minded scholar, he looked always at the contemporary experiences in Europe and, as a scientist and cultivated human being, he sought to serve the community by enthusiastically devoting himself also to education and public outreach. He developed clear interests in literature and, as a forerunner, he dared to tackle the genre of science fiction. His short novel Relazione del viaggio alla Luna fatto da una donna nell'anno di grazia 2057 (Report of the Trip to the Moon done by a Woman in the Year of our Lord 2057), written in the period of his exile from the Observatory and practically given up as lost until a private copy was found in the library of one of Capocci's descendants, offers an interesting overview of astronomical knowledge and taste for the elegance in writing, and gives an unusual, and often ironic, viewpoint on the situation of sciences in Naples in the middle of the 19th century.

  8. One of the origins of modernity and naturalism of French literature in the 19th century.

    PubMed

    Lee, Chan-Kyu; Lee, Na-Mi

    2013-04-01

    Authors studied how Claude Bernard, the first founder of experimental medicine, contributed significantly to establishment of modernism and influenced European modern culture. Authors first studied his views on modernity, comparing with Descartes and Magendie, and on the similarity between "Experimental medicine" and the European literature in the 19th century. Bernard was not exclusively against vitalism, but the dogmatic misuse of vitalism. His objective thinking could be a useful model for the authors, who considered science to be an origin of modernity in literature of naturalism. Especially, Emile Zola was strongly influenced by Bernard's "An introduction to the study of Experimental medicine" and published "Experimental novel," a manifesto of naturalism. Although Bernard's experimental methodology and determinism deeply influenced modern European culture, the relationship between his Experimental medicine and modernism have not been fully investigated yet. His experimental medicine also needs to be discussed from the ecological viewpoints. His anthropo-centrism was unique since he emphasized any human theory could not surpass the principle of nature. Conventional anthropo-centrism claims that human beings are superior enough to own and govern the nature. And Bernard's the necessary determinism contains the ecological principle that all life forms and inanimate objects are organically related and intertwined to each other, irrespectively of their usefulness for the human beings. Although there were some ethical debates related to his medical experiments on living bodies of animal, his strict principle to perform experiments only after animal or human body died was worth considering as an effort to sustain ecological viewpoints. He was also unique in terms of being realistic and candid about his situation which was limited by the 19th century's scientific and medical development. In conclusion, the significance of convergence of literature and medical science

  9. Ochres and earths: Matrix and chromophores characterization of 19th and 20th century artist materials

    NASA Astrophysics Data System (ADS)

    Montagner, Cristina; Sanches, Diogo; Pedroso, Joana; Melo, Maria João; Vilarigues, Márcia

    2013-02-01

    The present paper describes the main results obtained from the characterization of a wide range of natural and synthetic ochre samples used in Portugal from the 19th to the 20th century, including powder and oil painting samples. The powder ochre samples came from several commercial distributors and from the collection of Joaquim Rodrigo (1912-1997), a leading Portuguese artist, particularly active during the sixties and seventies. The micro-samples of oil painting tubes came from the Museu Nacional de Arte Contemporânea-Museu do Chiado (National Museum of Contemporary Art-Chiado Museum) in Lisbon and were used by Columbano Bordalo Pinheiro (1857-1929), one of the most prominent naturalist Portuguese painters. These tubes were produced by the main 19th century colourmen: Winsor & Newton, Morin et Janet, Maison Merlin, and Lefranc. The samples have been studied using μ-Fourier Transform Infrared Spectroscopy (μ-FTIR), Raman microscopy, μ-Energy Dispersive X-ray fluorescence (μ-EDXRF), and X-ray diffraction (XRD). The analyzed ochres were found to be a mixture of several components: iron oxides and hydroxides in matrixes with kaolinite, gypsum and chalk. The results obtained allowed to identify and characterize the ochres according to their matrix and chromophores. The main chromophores where identified by Raman microscopy as being hematite, goethite and magnetite. The infrared analysis of the ochre samples allowed to divide them into groups, according to the composition of the matrix. It was possible to separate ochres containing kaolinite matrix and/or sulfate matrix from ochres where only iron oxides and/or hydroxides were detected. μ-EDXRF and Raman were the best techniques to identify umber, since the presence of elements such as manganese is characteristic of these pigments. μ-EDXRF also revealed the presence of significant amounts of arsenic in all Sienna tube paints.

  10. Ochres and earths: matrix and chromophores characterization of 19th and 20th century artist materials.

    PubMed

    Montagner, Cristina; Sanches, Diogo; Pedroso, Joana; Melo, Maria João; Vilarigues, Márcia

    2013-02-15

    The present paper describes the main results obtained from the characterization of a wide range of natural and synthetic ochre samples used in Portugal from the 19th to the 20th century, including powder and oil painting samples. The powder ochre samples came from several commercial distributors and from the collection of Joaquim Rodrigo (1912-1997), a leading Portuguese artist, particularly active during the sixties and seventies. The micro-samples of oil painting tubes came from the Museu Nacional de Arte Contemporânea-Museu do Chiado (National Museum of Contemporary Art-Chiado Museum) in Lisbon and were used by Columbano Bordalo Pinheiro (1857-1929), one of the most prominent naturalist Portuguese painters. These tubes were produced by the main 19th century colourmen: Winsor & Newton, Morin et Janet, Maison Merlin, and Lefranc. The samples have been studied using μ-Fourier Transform Infrared Spectroscopy (μ-FTIR), Raman microscopy, μ-Energy Dispersive X-ray fluorescence (μ-EDXRF), and X-ray diffraction (XRD). The analyzed ochres were found to be a mixture of several components: iron oxides and hydroxides in matrixes with kaolinite, gypsum and chalk. The results obtained allowed to identify and characterize the ochres according to their matrix and chromophores. The main chromophores where identified by Raman microscopy as being hematite, goethite and magnetite. The infrared analysis of the ochre samples allowed to divide them into groups, according to the composition of the matrix. It was possible to separate ochres containing kaolinite matrix and/or sulfate matrix from ochres where only iron oxides and/or hydroxides were detected. μ-EDXRF and Raman were the best techniques to identify umber, since the presence of elements such as manganese is characteristic of these pigments. μ-EDXRF also revealed the presence of significant amounts of arsenic in all Sienna tube paints.

  11. Ochres and earths: matrix and chromophores characterization of 19th and 20th century artist materials.

    PubMed

    Montagner, Cristina; Sanches, Diogo; Pedroso, Joana; Melo, Maria João; Vilarigues, Márcia

    2013-02-15

    The present paper describes the main results obtained from the characterization of a wide range of natural and synthetic ochre samples used in Portugal from the 19th to the 20th century, including powder and oil painting samples. The powder ochre samples came from several commercial distributors and from the collection of Joaquim Rodrigo (1912-1997), a leading Portuguese artist, particularly active during the sixties and seventies. The micro-samples of oil painting tubes came from the Museu Nacional de Arte Contemporânea-Museu do Chiado (National Museum of Contemporary Art-Chiado Museum) in Lisbon and were used by Columbano Bordalo Pinheiro (1857-1929), one of the most prominent naturalist Portuguese painters. These tubes were produced by the main 19th century colourmen: Winsor & Newton, Morin et Janet, Maison Merlin, and Lefranc. The samples have been studied using μ-Fourier Transform Infrared Spectroscopy (μ-FTIR), Raman microscopy, μ-Energy Dispersive X-ray fluorescence (μ-EDXRF), and X-ray diffraction (XRD). The analyzed ochres were found to be a mixture of several components: iron oxides and hydroxides in matrixes with kaolinite, gypsum and chalk. The results obtained allowed to identify and characterize the ochres according to their matrix and chromophores. The main chromophores where identified by Raman microscopy as being hematite, goethite and magnetite. The infrared analysis of the ochre samples allowed to divide them into groups, according to the composition of the matrix. It was possible to separate ochres containing kaolinite matrix and/or sulfate matrix from ochres where only iron oxides and/or hydroxides were detected. μ-EDXRF and Raman were the best techniques to identify umber, since the presence of elements such as manganese is characteristic of these pigments. μ-EDXRF also revealed the presence of significant amounts of arsenic in all Sienna tube paints. PMID:23274225

  12. Solar cycle effect on atmospheric carbon dioxide levels. Final report

    SciTech Connect

    Kirk, B.L.; Rust, B.W.

    1983-01-01

    The authors present a causal time-series model for the Mauna Loa atmospheric CO2 record which supersedes a mathematical model consisting of four effects represented by exponential and sine functions. One effect is a 142-month oscillation which trails the sunspot numbers by exactly a quarter-cycle. This suggests that solar activity affects the rate of change in the atmospheric CO2 abundance. The new model replaces the mathematical functions with four measured time series representing proposed physical causes and reduces the number of adjustable parameters from 13 to 5 with no significant deterioration in the fit. The authors present evidence that solar activity affects the CO2 abundance through variations in ocean temperature or circulation.

  13. The first Forbush decrease of solar cycle 24

    NASA Astrophysics Data System (ADS)

    Papaioannou, A.; Belov, A.; Mavromichalaki, H.; Eroshenko, E.; Yanke, V.; Asvestari, E.; Abunin, A.; Abunina, M.

    2013-02-01

    The first significant Forbush decrease of solar cycle 24 was recorded in February 18, 2011 from neutron monitors around the world. This was the result of the coronal mass ejections (CMEs) that was released from the Sun on 14 and 15 February 2011, respectively, and their interplanetary counterparts (ICME) that were prevalent in the interplanetary space in this period. We report on the global characteristics of cosmic rays during the FD such as the amplitude (A0), the decrement and the three dimensional anisotropy parameters (Ax, Ay and Az), deduced from the global survey method (GSM). We also analyze the interplanetary space solar wind data and we present the structure of the ICME as it passed through the Earth resulting in a strong Forbush decrease. We compare high time resolution neutron monitor data with multipoint space-based measurements of the interplanetary space (e.g. ACE/SWEPAM and ACE/MAG).

  14. The variations of prominence activities during solar cycle

    NASA Astrophysics Data System (ADS)

    Shimojo, Masumi

    The prominence activities (prominence eruption/disappearance) in the solar atmosphere closely relate with the CMEs that cause great influences on heliosphere and magnetosphere. Gopal-swarmy et al. (2003) reported that 72 The Nobeyama Radioheliograph (NoRH) is observing Sun in microwave (17 GHz) since 1992. At a flare, the main component of the microwave from Sun is emitted from non-thermal electrons that are accelerated by flare. On the other hand, the main component of the microwave is thermal emission when Sun is quiet, and a prominence is clearly observed in microwave because there is the prominence on the limb. We developed the automatic prominence activity detection program based on 17 GHz images observed by NoRH, and investigated the variation of the properties of the prominence activities that oc-curred from 1992 to the end of 2009. We found the following results. 1. The variation in the number of prominence activities is similar to that of sunspots during one solar cycle but there are differences between the peak times of prominence activities and sunspots. 2. The frequency distribution as a function of the magnitude of the prominence activities the size of activated prominences at each phase shows a power-law distribution. The power-law index of the distribution does not change except around the solar minimum. 3. The number of promi-nence activities has a dependence on the latitude On the other hand the average magnitude is independent of the latitude. In the paper, we will also discuss the relationship the other properties of prominence eruptions, solar cycle and the photospheric magnetic field.

  15. Solar photospheric network properties and their cycle variation

    SciTech Connect

    Thibault, K.; Charbonneau, P.; Béland, M. E-mail: paulchar@astro.umontreal.ca-b

    2014-11-20

    We present a numerical simulation of the formation and evolution of the solar photospheric magnetic network over a full solar cycle. The model exhibits realistic behavior as it produces large, unipolar concentrations of flux in the polar caps, a power-law flux distribution with index –1.69, a flux replacement timescale of 19.3 hr, and supergranule diameters of 20 Mm. The polar behavior is especially telling of model accuracy, as it results from lower-latitude activity, and accumulates the residues of any potential modeling inaccuracy and oversimplification. In this case, the main oversimplification is the absence of a polar sink for the flux, causing an amount of polar cap unsigned flux larger than expected by almost one order of magnitude. Nonetheless, our simulated polar caps carry the proper signed flux and dipole moment, and also show a spatial distribution of flux in good qualitative agreement with recent high-latitude magnetographic observations by Hinode. After the last cycle emergence, the simulation is extended until the network has recovered its quiet Sun initial condition. This permits an estimate of the network relaxation time toward the baseline state characterizing extended periods of suppressed activity, such as the Maunder Grand Minimum. Our simulation results indicate a network relaxation time of 2.9 yr, setting 2011 October as the soonest the time after which the last solar activity minimum could have qualified as a Maunder-type Minimum. This suggests that photospheric magnetism did not reach its baseline state during the recent extended minimum between cycles 23 and 24.

  16. Solar Spectral Irradiance Variations in 240 - 1600 nm During the Recent Solar Cycles 21 - 23

    NASA Astrophysics Data System (ADS)

    Pagaran, J.; Weber, M.; Deland, M. T.; Floyd, L. E.; Burrows, J. P.

    2011-08-01

    Regular solar spectral irradiance (SSI) observations from space that simultaneously cover the UV, visible (vis), and the near-IR (NIR) spectral region began with SCIAMACHY aboard ENVISAT in August 2002. Up to now, these direct observations cover less than a decade. In order for these SSI measurements to be useful in assessing the role of the Sun in climate change, records covering more than an eleven-year solar cycle are required. By using our recently developed empirical SCIA proxy model, we reconstruct daily SSI values over several decades by using solar proxies scaled to short-term SCIAMACHY solar irradiance observations to describe decadal irradiance changes. These calculations are compared to existing solar data: the UV data from SUSIM/UARS, from the DeLand & Cebula satellite composite, and the SIP model (S2K+VUV2002); and UV-vis-IR data from the NRLSSI and SATIRE models, and SIM/SORCE measurements. The mean SSI of the latter models show good agreement (less than 5%) in the vis regions over three decades while larger disagreements (10 - 20%) are found in the UV and IR regions. Between minima and maxima of Solar Cycles 21, 22, and 23, the inferred SSI variability from the SCIA proxy is intermediate between SATIRE and NRLSSI in the UV. While the DeLand & Cebula composite provide the highest variability between solar minimum and maximum, the SIP/Solar2000 and NRLSSI models show minimum variability, which may be due to the use of a single proxy in the modeling of the irradiances. In the vis-IR spectral region, the SCIA proxy model reports lower values in the changes from solar maximum to minimum, which may be attributed to overestimations of the sunspot proxy used in modeling the SCIAMACHY irradiances. The fairly short timeseries of SIM/SORCE shows a steeper decreasing (increasing) trend in the UV (vis) than the other data during the descending phase of Solar Cycle 23. Though considered to be only provisional, the opposite trend seen in the visible SIM data

  17. HEMISPHERIC ASYMMETRIES IN THE POLAR SOLAR WIND OBSERVED BY ULYSSES NEAR THE MINIMA OF SOLAR CYCLES 22 AND 23

    SciTech Connect

    Ebert, R. W.; Dayeh, M. A.; Desai, M. I.; McComas, D. J.; Pogorelov, N. V.

    2013-05-10

    We examined solar wind plasma and interplanetary magnetic field (IMF) observations from Ulysses' first and third orbits to study hemispheric differences in the properties of the solar wind and IMF originating from the Sun's large polar coronal holes (PCHs) during the declining and minimum phase of solar cycles 22 and 23. We identified hemispheric asymmetries in several parameters, most notably {approx}15%-30% south-to-north differences in averages for the solar wind density, mass flux, dynamic pressure, and energy flux and the radial and total IMF magnitudes. These differences were driven by relatively larger, more variable solar wind density and radial IMF between {approx}36 Degree-Sign S-60 Degree-Sign S during the declining phase of solar cycles 22 and 23. These observations indicate either a hemispheric asymmetry in the PCH output during the declining and minimum phase of solar cycles 22 and 23 with the southern hemisphere being more active than its northern counterpart, or a solar cycle effect where the PCH output in both hemispheres is enhanced during periods of higher solar activity. We also report a strong linear correlation between these solar wind and IMF parameters, including the periods of enhanced PCH output, that highlight the connection between the solar wind mass and energy output and the Sun's magnetic field. That these enhancements were not matched by similar sized variations in solar wind speed points to the mass and energy responsible for these increases being added to the solar wind while its flow was subsonic.

  18. Solar Sources and Geospace Consequences of Interplanetary Magnetic Clouds Observed During Solar Cycle 23

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; Akiyama, S.; Yashiro, S.; Michalek, G.; Lepping, R. P.

    2007-01-01

    We present results of a statistical investigation of 99 magnetic clouds (MCs) observed during 1995-2005. The MC-associated coronal mass ejections (CMEs) are faster and wider on the average and originate within +/-30deg from the solar disk center. The solar sources of MCs also followed the butterfly diagram. The correlation between the magnetic field strength and speed of MCs was found to be valid over a much wider range of speeds. The number of south-north (SN) MCs was dominant and decreased with solar cycle, while the number of north-south (NS) MCs increased confirming the odd-cycle behavior. Two-thirds of MCs were geoeffective; the Dst index was highly correlated with speed and magnetic field in MCs as well as their product. Many (55%) fully northward (FN) MCs were geoeffective solely due to their sheaths. The non-geoeffective MCs were slower (average speed approx. 382 km/s), had a weaker southward magnetic field (average approx. -5.2nT), and occurred mostly during the rise phase of the solar activity cycle.

  19. CORONAL MASS EJECTIONS AND SUNSPOTS-SOLAR CYCLE PERSPECTIVE

    SciTech Connect

    Ramesh, K. B.

    2010-03-20

    Recent studies have indicated that the occurrence of the maxima of coronal mass ejection (CME) rate and sunspot number (SSN) were nearly two years apart. We find that the two-year lag of CME rate manifests only when the SSN index is considered and the lag is minimal (two-three months) when the sunspot area is considered. CMEs with speeds greater than the average speed follow the sunspot cycle much better than the entire population of CMEs. Analysis of the linear speeds of CMEs further indicates that during the descending phase of the solar cycle the loss of magnetic flux is through more frequent and less energetic CMEs. We emphasize that the magnetic field attaining the nonpotentiality that represents the free energy content, rather than the flux content as measured by the area of the active region, plays an important role in producing CMEs.

  20. Detection of solar-type cycles in cataclysmic variables

    NASA Astrophysics Data System (ADS)

    Bianchini, A.

    The author suggests that the presence of solar type cycles in the late-type secondaries of cataclysmic variables can modulate the mass transfer rate within these systems. This will ultimately produce a more or less periodic variation of both: (1) the observed "quiescent" luminosities of old-novae and nova-like systems; and (2) the time intervals between consecutive outbursts of dwarf-nova systems. Statistical analysis of the long term light curves of the old-novae GK Per (1901), Q Cyg (1876) and V841 Oph (1848), the nova-like system TT Ari, and the two dwarf-nova prototype systems SS Cyg and U Gem has revealed the existence of main cycles of activity.

  1. Study of Distribution and Asymmetry of Solar Active Prominences during Solar Cycle 23

    NASA Astrophysics Data System (ADS)

    Joshi, Navin Chandra; Bankoti, Neeraj Singh; Pande, Seema; Pande, Bimal; Pandey, Kavita

    2009-12-01

    In this article we present the results of a study of the spatial distribution and asymmetry of solar active prominences (SAP) for the period 1996 through 2007 (solar cycle 23). For more meaningful statistical analysis we analyzed the distribution and asymmetry of SAP in two subdivisions viz. Group1 (ADF, APR, DSF, CRN, CAP) and Group2 (AFS, ASR, BSD, BSL, DSD, SPY, LPS). The North - South (N - S) latitudinal distribution shows that the SAP events are most prolific in the 21° to 30° slice in the Northern and Southern Hemispheres; the East - West (E - W) longitudinal distribution study shows that the SAP events are most prolific (best observable) in the 81° to 90° slice in the Eastern and Western Hemispheres. It was found that the SAP activity during this cycle is low compared to previous solar cycles. The present study indicates that during the rising phase of the cycle the number of SAP events are roughly equal in the Northern and Southern Hemispheres. However, activity in the Southern Hemisphere has been dominant since 1999. Our statistical study shows that the N - S asymmetry is more significant then the E - W asymmetry.

  2. High-Energy Solar Particle Events in Cycle 24

    NASA Technical Reports Server (NTRS)

    Gopalswamy, N.; Makela, P.; Yashiro, S.; Xie, H.; Akiyama, S.; Thakur, N.

    2015-01-01

    The Sun is already in the declining phase of cycle 24, but the paucity of high-energy solar energetic particle (SEP) events continues with only two ground level enhancement (GLE) events as of March 31, 2015. In an attempt to understand this, we considered all the large SEP events of cycle 24 that occurred until the end of 2014. We compared the properties of the associated CMEs with those in cycle 23. We found that the CME speeds in the sky plane were similar, but almost all those cycle-24 CMEs were halos. A significant fraction of (16%) of the frontside SEP events were associated with eruptive prominence events. CMEs associated with filament eruption events accelerate slowly and attain peak speeds beyond the typical GLE release heights. When we considered only western hemispheric events that had good connectivity to the CME nose, there were only 8 events that could be considered as GLE candidates. One turned out to be the first GLE event of cycle 24 (2012 May 17). In two events, the CMEs were very fast (>2000 km/s) but they were launched into a tenuous medium (high Alfven speed). In the remaining five events, the speeds were well below the typical GLE CME speed (2000 km/s). Furthermore, the CMEs attained their peak speeds beyond the typical heights where GLE particles are released. We conclude that several factors contribute to the low rate of high-energy SEP events in cycle 24: (i) reduced efficiency of shock acceleration (weak heliospheric magnetic field), (ii) poor latitudinal and longitudinal connectivity), and (iii) variation in local ambient conditions (e.g., high Alfven speed).

  3. Limits to solar cycle predictability: Cross-equatorial flux plumes

    NASA Astrophysics Data System (ADS)

    Cameron, R. H.; Dasi-Espuig, M.; Jiang, J.; Işık, E.; Schmitt, D.; Schüssler, M.

    2013-09-01

    Context. Within the Babcock-Leighton framework for the solar dynamo, the strength of a cycle is expected to depend on the strength of the dipole moment or net hemispheric flux during the preceding minimum, which depends on how much flux was present in each hemisphere at the start of the previous cycle and how much net magnetic flux was transported across the equator during the cycle. Some of this transport is associated with the random walk of magnetic flux tubes subject to granular and supergranular buffeting, some of it is due to the advection caused by systematic cross-equatorial flows such as those associated with the inflows into active regions, and some crosses the equator during the emergence process. Aims: We aim to determine how much of the cross-equatorial transport is due to small-scale disorganized motions (treated as diffusion) compared with other processes such as emergence flux across the equator. Methods: We measure the cross-equatorial flux transport using Kitt Peak synoptic magnetograms, estimating both the total and diffusive fluxes. Results: Occasionally a large sunspot group, with a large tilt angle emerges crossing the equator, with flux from the two polarities in opposite hemispheres. The largest of these events carry a substantial amount of flux across the equator (compared to the magnetic flux near the poles). We call such events cross-equatorial flux plumes. There are very few such large events during a cycle, which introduces an uncertainty into the determination of the amount of magnetic flux transported across the equator in any particular cycle. As the amount of flux which crosses the equator determines the amount of net flux in each hemisphere, it follows that the cross-equatorial plumes introduce an uncertainty in the prediction of the net flux in each hemisphere. This leads to an uncertainty in predictions of the strength of the following cycle.

  4. A high temperature Rankine binary cycle for ground and space solar engine applications

    NASA Technical Reports Server (NTRS)

    Hertzberg, A.; Lau, C.-V.

    1978-01-01

    A Rankine cycle covering the range of plasma temperatures possible from a solar radiation boiler is studied. The working fluid is potassium. A binary cycle with potassium as the topping cycle fluid and a conventional steam cycle as the bottoming cycle for earth-based applications is analyzed. Operation in conjunction with a wave energy exchanger is considered.

  5. Structure and sources of solar wind in the growing phase of 24th solar cycle

    NASA Astrophysics Data System (ADS)

    Slemzin, Vladimir; Goryaev, Farid; Shugay, Julia; Rodkin, Denis; Veselovsky, Igor

    2015-04-01

    We present analysis of the solar wind (SW) structure and its association with coronal sources during the minimum and rising phase of 24th solar cycle (2009-2011). The coronal sources prominent in this period - coronal holes, small areas of open magnetic fields near active regions and transient sources associated with small-scale solar activity have been investigated using EUV solar images and soft X-ray fluxes obtained by the CORONAS-Photon/TESIS/Sphinx, PROBA2/SWAP, Hinode/EIS and AIA/SDO instruments as well as the magnetograms obtained by HMI/SDO. It was found that at solar minimum (2009) velocity and magnetic field strength of high speed wind (HSW) and transient SW from small-scale flares did not differ significantly from those of the background slow speed wind (SSW). The major difference between parameters of different SW components was seen in the ion composition represented by the C6/C5, O7/O6, Fe/O ratios and the mean charge of Fe ions. With growing solar activity, the speed of HSW increased due to transformation of its sources - small-size low-latitude coronal holes into equatorial extensions of large polar holes. At that period, the ion composition of transient SW changed from low-temperature to high-temperature values, which was caused by variation of the source conditions and change of the recombination/ionization rates during passage of the plasma flow through the low corona. However, we conclude that criteria of separation of the SW components based on the ion ratios established earlier by Zhao&Fisk (2009) for higher solar activity are not applicable to the extremely weak beginning of 24th cycle. The research leading to these results has received funding from the European Commission's Seventh Framework Programme (FP7/2007-2013) under the grant agreement eHeroes (project n° 284461, www.eheroes.eu).

  6. Hay fever, a post industrial revolution epidemic: a history of its growth during the 19th century.

    PubMed

    Emanuel, M B

    1988-05-01

    Although other forms of allergic disease were described in antiquity, hay fever is surprisingly modern. Very rare descriptions can be traced back to Islamic texts of the 9th century and European texts of the 16th century. It was only in the early 19th century that the disease was carefully described and at that time was regarded as most unusual. By the end of the 19th century it had become commonplace in both Europe and North America. This paper attempts to chart the growth of hay fever through the medical literature of the 19th century. It is hoped that an understanding of the increase in prevalence between 1820 and 1900 may provide an insight for modern researchers and give some clues into possible reasons for the epidemic nature of the disease today.

  7. Ionospheric response to great geomagnetic storms during solar cycle 23

    NASA Astrophysics Data System (ADS)

    Merline Matamba, Tshimangadzo; Bosco Habarulema, John

    2016-07-01

    The analyses of ionospheric responses due to great geomagnetic storms i.e. Dst index < 350 nT that occurred during solar cycle 23 are presented. The GPS Total Electron Content (TEC) and ionosonde data over Southern and Northern Hemisphere mid-latitudes were used to study the ionospheric responses. A geomagnetic latitude region of ±30° to ±46° within a longitude sector of 15° to 40° was considered. Using a criteria of Dst < -350 nT, there were only four great storm periods (29 March - 02 April 2001, 27 - 31 October 2003, 18 - 23 November 2003 and 06 - 11 November 2004) in solar cycle 23. Analysis has shown that ionospheric dynamics during these disturbed conditions could be due to a number of dynamic and electrodynamics processes in both Hemispheres. In some instances the ionosphere responds differently to the same storm condition in both Hemispheres. Physical mechanisms related to (but not limited to) composition changes and electric fields will be discussed.

  8. Solar energy demand (SED) of commodity life cycles.

    PubMed

    Rugani, Benedetto; Huijbregts, Mark A J; Mutel, Christopher; Bastianoni, Simone; Hellweg, Stefanie

    2011-06-15

    The solar energy demand (SED) of the extraction of 232 atmospheric, biotic, fossil, land, metal, mineral, nuclear, and water resources was quantified and compared with other energy- and exergy-based indicators. SED represents the direct and indirect solar energy required by a product or service during its life cycle. SED scores were calculated for 3865 processes, as implemented in the Ecoinvent database, version 2.1. The results showed that nonrenewable resources, and in particular minerals, formed the dominant contribution to SED. This large share is due to the indirect solar energy required to produce these resource inputs. Compared with other energy- and exergy-based indicators, SED assigns higher impact factors to minerals and metals and smaller impact factors to fossil energetic resources, land use, and nuclear energy. The highest differences were observed for biobased and renewable energy generation processes, whose relative contribution of renewable resources such as water, biomass, and land occupation was much lower in SED than in energy- and exergy-based indicators.

  9. Solar energy demand (SED) of commodity life cycles.

    PubMed

    Rugani, Benedetto; Huijbregts, Mark A J; Mutel, Christopher; Bastianoni, Simone; Hellweg, Stefanie

    2011-06-15

    The solar energy demand (SED) of the extraction of 232 atmospheric, biotic, fossil, land, metal, mineral, nuclear, and water resources was quantified and compared with other energy- and exergy-based indicators. SED represents the direct and indirect solar energy required by a product or service during its life cycle. SED scores were calculated for 3865 processes, as implemented in the Ecoinvent database, version 2.1. The results showed that nonrenewable resources, and in particular minerals, formed the dominant contribution to SED. This large share is due to the indirect solar energy required to produce these resource inputs. Compared with other energy- and exergy-based indicators, SED assigns higher impact factors to minerals and metals and smaller impact factors to fossil energetic resources, land use, and nuclear energy. The highest differences were observed for biobased and renewable energy generation processes, whose relative contribution of renewable resources such as water, biomass, and land occupation was much lower in SED than in energy- and exergy-based indicators. PMID:21545085

  10. SOLAR CYCLE VARIATION OF SOUND SPEED INSIDE THE SUN

    SciTech Connect

    Mullan, D. J.; MacDonald, J.; Rabello-Soares, M. C.

    2012-08-10

    Empirical radial profiles of the changes in sound speed inside the Sun between solar minimum and solar maximum have been extracted from Michelson Doppler Imager data by Baldner and Basu and Rabello-Soares. Here, we compare these results with the theoretical radial profiles predicted by a model of magnetic inhibition of convective onset: In the model, the degree of magnetic inhibition is characterized by a parameter {delta}, which is essentially the ratio of magnetic pressure to gas pressure. We find that the theoretical profiles overlap significantly with the empirical results in the outer half of the convection zone. But differences in the deeper layers indicate that the model needs to be modified there. The main result that emerges in the present comparison is that the value of {delta} must be larger near the surface than at great depth. A secondary result is that, in the course of the solar cycle, the magnetic field magnitude at the base of the convection zone may be out of phase with the field near the surface.

  11. Solar-cycle variations of the internetwork magnetic field

    NASA Astrophysics Data System (ADS)

    Faurobert, M.; Ricort, G.

    2015-10-01

    Context. The quiet Sun exhibits a rich and complex magnetic structuring that is still not fully resolved or understood. Aims: We intend to contribute to the debate about the origin of the internetwork magnetic fields and whether or not they are related to the global solar dynamo. Methods: We analyzed center-to-limb polarization measurements obtained with the SOT/SP spectropolarimeter onboard the Hinode satellite outside active regions in 2007 and 2013, that is, at a minimum and a maximum of the solar cycle, respectively. We examined 10'' × 10'' maps of the unsigned circular and linear polarization in the FeI 630.25 nm line in regions located away from network elements. The maps were corrected for bias and focus variations between the two data sets. Then we applied a Fourier spectral analysis to examine wether the spatial structuring of the internetwork magnetic fields shows significant differences between the minimum and maximum of the cycle. Results: Neither the mean values of the unsigned circular and linear polarizations in the selected 10'' × 10'' maps nor their spatial fluctuation power spectra show significant center-to-limb variations. For the unsigned circular polarization the power of the spatial fluctuations is lower in 2013 than in 2007, but the spectral slope is unchanged. The linear polarization spectra show no significant differences in 2013 and 2007, but the spectrum of 2013 is more strongly affected by noise. Conclusions: The small-scale magnetic structuring in the internetwork is different in our 2013 and 2007 data. Surprisingly, we find a lower spatial fluctuation power at the solar maximum in the internetwork magnetic structuring. This indicates some complex interactions between the small-scale magnetic structures in the quiet Sun and the global dynamo, as predicted by recent numerical simulations. This result has to be confirmed by further statistical studies with larger data sets.

  12. EDITORIAL: Selected papers from the 19th International Colloquium on Magnetic Films and Surfaces

    NASA Astrophysics Data System (ADS)

    Miyazaki, T.; Inoue, J.

    2007-03-01

    The 19th International Colloquium on Magnetic Films and Surfaces (ICMFS 2006) was held on 14-18 August 2006 at the Sendai International Center in Sendai, Japan. The purpose of the Colloquium was to bring together scientists working on magnetic thin films and surfaces and to provide an opportunity for presentation and discussion of recent experimental and theoretical advances in the field. 285 scientists from 17 countries (Japan: 167, overseas: 118) participated in the Colloquium, as well as 6 family members. There were 56 oral and 178 poster presentations. The oral presentations consisted of 3 plenary talks, 23 invited talks and 30 contributed talks. The number of presentations by scientific category are as follows: Spin dependent transport: 43 Magnetic storage/memory: 9 Magnetization reversal and fast dynamics: 15 Spin injection and spin transfer torque: 26 Magnetic thin films and multilayers: 71 High spin polarization materials: 17 Hard and soft magnetic materials: 3 Magneto-optics: 5 Characterization techniques for thin films and surfaces: 7 Exchange coupling: 13 Micro- and nanopatterned magnetic structures: 18 Micromagnetic modelling: 2 One of the characteristics of the present Colloquium is an increase in the number of presentations in the field of spin-electronics, as seen above. This Cluster Issue of Journal of Physics D: Applied Physics includes several important papers in this rapidly developing field. We believe that, in the future, the field of magnetic materials will maintain its popularity and, on top of that, other fields such as spintronics materials, materials related to life sciences and medicine and also materials related to the environment will be investigated further. The ICMFS Conference started in London in 1964, and is now one of the world-wide conferences on magnetism. The Colloquium has been held in Japan four times now: the previous ones being the 5th ICMFS in the Mount Fuji area, the 10th at Yokohama and the 17th at Kyoto, which was

  13. Contemporaneous anatomic collections and scientific papers from the 19th century school of anatomy of Bologna: preliminary report.

    PubMed

    Scarani, P; de Caro, R; Ottani, V; Raspanti, M; Ruggeri, F; Ruggeri, A

    2001-01-01

    Recently, a strict relationship was demonstrated between scientific pathology reports of the 19th century and a large number of specimens from the museum of pathology 'Cesare Taruffi' of Bologna. Such an experience suggested verifying whether a similar relationship exists between the 19th-century collections of the museum of anatomy and the contemporaneous anatomic scientific literature. The purpose of this preliminary report is to illustrate the first documented samples recovered in Bologna in order to promote such an inventory of old anatomic and pathologic specimens in other museums.

  14. Unusual Polar Conditions in Solar Cycle 24 and Their Implications for Cycle 25

    NASA Astrophysics Data System (ADS)

    Gopalswamy, Nat; Yashiro, Seiji; Akiyama, Sachiko

    2016-05-01

    We report on the prolonged solar-maximum conditions until late 2015 at the north-polar region of the Sun indicated by the occurrence of high-latitude prominence eruptions (PEs) and microwave brightness temperature close to the quiet-Sun level. These two aspects of solar activity indicate that the polarity reversal was completed by mid-2014 in the south and late 2015 in the north. The microwave brightness in the south-polar region has increased to a level exceeding the level of the Cycle 23/24 minimum, but just started to increase in the north. The north-south asymmetry in the polarity reversal has switched from that in Cycle 23. These observations lead us to the hypothesis that the onset of Cycle 25 in the northern hemisphere is likely to be delayed with respect to that in the southern hemisphere. We find that the unusual condition in the north is a direct consequence of the arrival of poleward surges of opposite polarity from the active region belt. We also find that multiple rush-to-the-pole episodes were indicated by the PE locations that lined up at the boundary between opposite-polarity surges. The high-latitude PEs occurred in the boundary between the incumbent polar flux and the insurgent flux of opposite polarity.

  15. Solar Wind Plasma Flows and Space Weather Aspects Recent Solar Cycle

    NASA Astrophysics Data System (ADS)

    Kaushik, Sonia; Kaushik, Subhash Chandra

    2016-07-01

    Solar transients are responsible for initiating short - term and long - term variations in earth's magnetosphere. These variations are termed as geomagnetic disturbances, and driven by the interaction of solar wind features with the geo-magnetosphere. The strength of this modulation process depends upon the magnitude and orientation of the Interplanetary Magnetic Field and solar wind parameters. These interplanetary transients are large scale structures containing plasma and magnetic field expelled from the transient active regions of solar atmosphere. As they come to interplanetary medium the interplanetary magnetic field drape around them. This field line draping was thought as possible cause of the characteristic eastward deflection and giving rise to geomagnetic activities as well as a prime factor in producing the modulation effects in the near Earth environment. The Solar cycle 23 has exhibited the unique extended minima and peculiar effects in the geomagnetosphere. Selecting such transients, occurred during this interval, an attempt has been made to determine quantitative relationships of these transients with solar/ interplanetary and Geophysical Parameters. In this work we used hourly values of IMF data obtained from the NSSD Center. The analysis mainly based on looking into the effects of these transients on earth's magnetic field. The high-resolution data IMF Bz and solar wind data obtained from WDC-A, through its omniweb, available during the selected period. Dst and Ap obtained from WDC-Kyoto are taken as indicator of geomagnetic activities. It is found that Dst index, solar wind velocity, proton temperature and the Bz component of magnetic field have higher values and increase just before the occurrence of these events. Larger and varying magnetic field mainly responsible for producing the short-term changes in geomagnetic intensity are observed during these events associated with coronal holes.

  16. The response of ozone to solar proton events during solar cycle 21 - The observations

    NASA Technical Reports Server (NTRS)

    Mcpeters, R. D.; Jackman, C. H.

    1985-01-01

    It is pointed out that during a solar proton event (SPE), large numbers of high-energy protons penetrate the earth's mesosphere and upper stratosphere and perturb the normal chemistry by ionizing molecules and changing the balance of odd nitrogen, oxygen, and hydrogen. Changes in ozone caused by an SPE are produced very rapidly, typically in a matter of hours, and are confined to a limited geographic area, the region above 60 deg geomagnetic latitude. In this paper, an analysis is reported of the response of ozone to the significant SPE's in solar cycle 21 from the Nimbus 7 launch in October 1978 to date, using data from the solar backscattered ultraviolet instrument (SBUV). Ozone data during 15 SPE's were examined. It was found that ozone depletion occurred during SPE's on at least five dates.

  17. Source of excitation of low-l solar p modes: characteristics and solar-cycle variations

    NASA Astrophysics Data System (ADS)

    Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.; Miller, B. A.; New, R.

    2000-05-01

    We investigate various properties of the excitation source that is responsible for driving the acoustic p-mode oscillations of the Sun. Current prejudice places this in the superadiabatic layer of the convection zone. We consider in detail how the precise nature of the resonant mode spectrum is modified: (i) as a result of the impact of different source-multipole mixtures; and (ii) as a function of the radial extent of the source. To do this, we model the observed resonant spectra with the solutions to a simple, one-dimensional wave equation which is intended to describe the essential elements of the solar resonant acoustic cavity. Further, we also fit these models to the low-l peaks in a high-resolution power spectrum generated from data collected by the Birmingham Solar-Oscillations Network (BiSON). We also use the extensive BiSON data set to search for variations in the source characteristics over the solar cycle.

  18. How to compare the faces of the Earth? Walachia in mid-19th century and nowadays

    NASA Astrophysics Data System (ADS)

    Bartos-Elekes, Zsombor; Magyari-Sáska, Zsolt; Timár, Gábor; Imecs, Zoltán

    2014-05-01

    In 1864 a detailed map was made about Walachia, its title is Charta României Meridionale (Map of Southern Romania), it has 112 map sheets, it is often called after his draughtsman: Szathmári's map. The map has an outstanding position in the history of Romanian cartography, because it indicates a turning-point. Before the map, foreigners (Austrians and Russians) had made topographic maps about this vassal principality of the Ottoman Empire. The Austrian topographic survey (1855-1859) - which served as a basis for this map - was the last one and the most detailed of these surveys. The map was made between the personal-union (1859) and independence (1878) of the Danubian Principalities. This map was the first (to a certain extent) own map of the forming country. In consequence of this survey and map, the Romanian mapping institute was founded, which one - based on this survey and map - began the topographic mapping of the country. In the Romanian scientific literature imperfect and contradictory information has been published about this map. Only a dozen copies of the map were kept in few map collections; the researchers could have reached them with difficulties. During our research we processed the circumstances of the survey and mapmaking discovering its documentation in the archives of Vienna, as well as using the Romanian, Hungarian and German scientific literature. We found the copies in map collections from Vienna to Bucharest. We digitized all the map sheets from different collections. We calculated the parameters of the used geodetic datum and map projection. We published on the web, such we made the map reachable for everybody. The map can be viewed in different zoom levels; can be downloaded; settlements can be found using the place name index; areas can be exported in modern projection, so the conditions of that time could be compared with today's reality. Our poster presents on the one hand the survey and the map realized in mid-19th century and our

  19. Analysis of Low Temperature Organic Rankine Cycles for Solar Applications

    NASA Astrophysics Data System (ADS)

    Li, Yunfei

    The present work focuses on Organic Rankine Cycle (ORC) systems and their application to low temperature waste heat recovery, combined heat and power as well as off-grid solar power generation applications. As CO_2 issues come to the fore front and fossil fuels become more expensive, interest in low grade heat recovery has grown dramatically in the past few years. Solar energy, as a clean, renewable, pollution-free and sustainable energy has great potential for the use of ORC systems. Several ORC solutions have been proposed to generate electricity from low temperature sources. The ORC systems discussed here can be applied to fields such as solar thermal, biological waste heat, engine exhaust gases, small-scale cogeneration, domestic boilers, etc. The current work presents a thermodynamic and economic analysis for the use of ORC systems to convert solar energy or low exergy energy to generate electrical power. The organic working fluids investigated here were selected to investigate the effect of the fluid saturation temperature on the performance of ORCs. The working fluids under investigation are R113, R245fa, R123, with boiling points between 40°C and 200°C at pressures from 10 kPa to 10 MPa. Ambient temperature air at 20oC to 30oC is utilized as cooling resource, and allowing for a temperature difference 10°C for effective heat transfer. Consequently, the working fluids are condensed at 40°C. A combined first- and second-law analysis is performed by varying some system independent parameters at various reference temperatures. The present work shows that ORC systems can be viable and economical for the applications such as waste heat use and off-grid power generation even though they are likely to be more expensive than grid power.

  20. Solar cycle dependence of ion cyclotron wave frequencies

    NASA Astrophysics Data System (ADS)

    Lessard, Marc R.; Lindgren, Erik A.; Engebretson, Mark J.; Weaver, Carol

    2015-06-01

    Electromagnetic ion cyclotron (EMIC) waves have been studied for decades, though remain a fundamentally important topic in heliospheric physics. The connection of EMIC waves to the scattering of energetic particles from Earth's radiation belts is one of many topics that motivate the need for a deeper understanding of characteristics and occurrence distributions of the waves. In this study, we show that EMIC wave frequencies, as observed at Halley Station in Antarctica from 2008 through 2012, increase by approximately 60% from a minimum in 2009 to the end of 2012. Assuming that these waves are excited in the vicinity of the plasmapause, the change in Kp in going from solar minimum to near solar maximum would drive increased plasmapause erosion, potentially shifting the generation region of the EMIC to lower L and resulting in the higher frequencies. A numerical estimate of the change in plasmapause location, however, implies that it is not enough to account for the shift in EMIC frequencies that are observed at Halley Station. Another possible explanation for the frequency shift, however, is that the relative density of heavier ions in the magnetosphere (that would be associated with increased solar activity) could account for the change in frequencies. In terms of effects on radiation belt dynamics, the shift to higher frequencies tends to mean that these waves will interact with less energetic electrons, although the details involved in this process are complex and depend on the specific plasma and gyrofrequencies of all populations, including electrons. In addition, the change in location of the generation region to lower L shells means that the waves will have access to higher number fluxes of resonant electrons. Finally, we show that a sunlit ionosphere can inhibit ground observations of EMIC waves with frequencies higher than ˜0.5 Hz and note that the effect likely has resulted in an underestimate of the solar-cycle-driven frequency changes described here.

  1. Solar Irradiance from 165 to 400 nm in 2008 and UV Variations in Three Spectral Bands During Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Meftah, M.; Bolsée, D.; Damé, L.; Hauchecorne, A.; Pereira, N.; Irbah, A.; Bekki, S.; Cessateur, G.; Foujols, T.; Thiéblemont, R.

    2016-10-01

    Accurate measurements of the solar spectral irradiance (SSI) and its temporal variations are of primary interest to better understand solar mechanisms, and the links between solar variability and Earth's atmosphere and climate. The SOLar SPECtrum (SOLSPEC) instrument of the Solar Monitoring Observatory (SOLAR) payload onboard the International Space Station (ISS) has been built to carry out SSI measurements from 165 to 3088 nm. We focus here on the ultraviolet (UV) part of the measured solar spectrum (wavelengths less than 400 nm) because the UV part is potentially important for understanding the solar forcing of Earth's atmosphere and climate. We present here SOLAR/SOLSPEC UV data obtained since 2008, and their variations in three spectral bands during Solar Cycle 24. They are compared with previously reported UV measurements and model reconstructions, and differences are discussed.

  2. Thermal stress cycling of GaAs solar cells

    NASA Technical Reports Server (NTRS)

    Janousek, B. K.; Francis, R. W.; Wendt, J. P.

    1985-01-01

    A thermal cycling experiment was performed on GaAs solar cells to establish the electrical and structural integrity of these cells under the temperature conditions of a simulated low-Earth orbit of 3-year duration. Thirty single junction GaAs cells were obtained and tests were performed to establish the beginning-of-life characteristics of these cells. The tests consisted of cell I-V power output curves, from which were obtained short-circuit current, open circuit voltage, fill factor, and cell efficiency, and optical micrographs, spectral response, and ion microprobe mass analysis (IMMA) depth profiles on both the front surfaces and the front metallic contacts of the cells. Following 5,000 thermal cycles, the performance of the cells was reexamined in addition to any factors which might contribute to performance degradation. It is established that, after 5,000 thermal cycles, the cells retain their power output with no loss of structural integrity or change in physical appearance.

  3. Cardiopulmonary resuscitation: a historical perspective leading up to the end of the 19th century.

    PubMed

    Ekmektzoglou, Konstantinos A; Johnson, Elizabeth O; Syros, Periklis; Chalkias, Athanasios; Kalambalikis, Lazaros; Xanthos, Theodoros

    2012-01-01

    Social laws and religious beliefs throughout history underscore the leaps and bounds that the science of resuscitation has achieved from ancient times until today. The effort to resuscitate victims goes back to ancient history, where death was considered a special form of sleep or an act of God. Biblical accounts of resuscitation attempts are numerous. Resuscitation in the Middle Ages was forbidden, but later during Renaissance, any prohibition against performing cardiopulmonary resuscitation (CPR) was challenged, which finally led to the Enlightenment, where scholars attempted to scientifically solve the problem of sudden death. It was then that the various components of CPR (ventilation, circulation, electricity, and organization of emergency medical services) began to take shape. The 19th century gave way to hallmarks both in the ventilatory support (intubation innovations and the artificial respirator) and the open-and closed chest circulatory support. Meanwhile, novel defibrillation techniques had been employed and ventricular fibrillation described. The groundbreaking discoveries of the 20th century finally led to the scientific framework of CPR. In 1960, mouth-to-mouth resuscitation was eventually combined with chest compression and defibrillation to become CPR as we now know it. This review presents the scientific milestones behind one of medicine's most widely used fields.

  4. Modelling the dynamics of scarlet fever epidemics in the 19th century.

    PubMed

    Duncan, S R; Scott, S; Duncan, C J

    2000-01-01

    Annual deaths from scarlet fever in Liverpool, UK during 1848-1900 have been used as a model system for studying the historical dynamics of the epidemics. Mathematical models are developed which include the growth of the population and the death rate from scarlet fever. Time-series analysis of the results shows that there were two distinct phases to the disease (i) 1848-1880: regular epidemics (wavelength = 3.7 years) consistent with the system being driven by an oscillation in the transmission coefficient (deltabeta) at its resonant frequency, probably associated with dry conditions in winter (ii) 1880-1900: an undriven SEIR system with a falling endemic level and decaying epidemics. This period was associated with improved nutritive levels. There is also evidence from time-series analysis that raised wheat prices in pregnancy caused increased susceptibility in the subsequent children. The pattern of epidemics and the demographic characteristics of the population can be replicated in the modelling which provides insights into the detailed epidemiology of scarlet fever in this community in the 19th century.

  5. [Development of the modern biological analogy concept in the 19th century].

    PubMed

    Bäumer, A

    1989-01-01

    At the beginning of the 19th century the term analogy was still synonymous with similarity, as for example in the case of Georges Cuvier. Exact criteria for determining analogy are first found in the work of Etienne Geoffroy Saint-Hilaire. Thereupon the English scientists Sharp MacLeay, William Swainson, John Obadiah Westwood and Edwin Strickland distinguished between analogy as correspondence between certain parts of the organism, i. e. only superficial resemblance, and affinity as an essential similarity in some remarkable aspects of form. Relying on these theories Richard Owen developed his theory of analogy ("a part which has the same function as another") and homology ("the same organ in different animals under every variety of form and function"). The criteria to distinguish between these two terms had to be modified and specified when the theory of evolution was developed by Charles Darwin. In the work of Thomas Henry Huxley, Ernst Haeckel and Carl Gegenbaur the modern biological term of analogy was developed, but at the same time it lost much of its importance and homology as a criterion for natural affinity became the central objective of further biological research. PMID:2534606

  6. Climate and history in the late 18th and early 19th centuries

    NASA Astrophysics Data System (ADS)

    Feldman, Theodore S.

    As in many areas of human knowledge, the notion of climate acquired a deeper historical content around the turn of the 19th century. Natural philosophers, geographers, and others became increasingly aware of climate's own history and its relation to human, plant and animal, and Earth history. This article examines several aspects of this “historicization” of climate.The lively 18th century discussion of the influence of climate on society is well known. Montesquieu is its most famous representative, but Voltaire, Hume, Kant, and others also participated. Their debate was literary more than scientific, their goal the understanding of man, not climate. Partly for this reason and partly because of the lack of good information on climates, they made no attempt to gather substantial climatic data. In fact, the importance of systematically collecting reliable data was scarcely understood in any area of natural philosophy before the last decades of the century [Cf. Frängsmyr et al., 1990; Feldman, 1990]. Instead, participants in the debate repeated commonplaces dating from Aristotle and Hippocrates and based their conclusions on unreliable reports from travelers. As Glacken wrote of Montesquieu, “his dishes are from old and well-tested recipes” [Glacken, 1967, chapter 12]. This is not to say that the debate over climatic influence was not significant—only that its significance lay more in the history of man than in the atmospheric sciences.

  7. Legacy Contaminantion in UK catchments since the mid-19th century

    NASA Astrophysics Data System (ADS)

    Howden, N. J. K.; Burt, T. P.; Worrall, F.; Noacco, V.; Wagener, T.

    2014-12-01

    We present data from UK catchments to characterise impacts of industrial and agricultural development of UK river catchments since the mid-19th century. We draw heavily on the world's longest continuous water quality monitoring programme in the Thames River Basin (1868-date) and discuss the implications of both agricultural development, social and industrial change, and the impact of legislation on coupled land and water resource systems. Our review draws on both data and model analysis over a 145-year period and explores how a multitude of inter-linked drivers affects process-function and practical water resource management decision-support. Our work uncovers key drivers, catchment responses and emergent challenges for process science and regulation, with particular emphasis on the technical challenge for catchment scientists to provide both insight and workable solutions to maintain food and water security in intensively management river basins. We discuss issues of appropriate methods for both data capture and subsequent analyses to support short- and long-term decision making, and particularly considers the importance of advanced techniques to clarify uncertainties in extrapolation of short-term observations to inform long-term goals. We speculate as to future trajectories of catchment responses to current pressures, and potential pitfalls to immediate concerns that may often be at odds with overall requirements for continued use of natural resources in the future.

  8. ["Fabulous things". Drug narratives about coca and cocaine in the 19th century].

    PubMed

    Wahrig, Bettina

    2009-12-01

    This contribution focuses on the history of Coca leaves and Cocaine in the second half of 19th century Europe. Even though, to date, no direct link has been established between the activities of the Milano physician Paolo Mantegazza, and the Göttingen chemist Friedrich Wöhler, it is not a mere coincidence that both published their findings in the same year, namely, 1859. Mantegazza authored the first treatise claiming that Coca had psychoactive qualities and touted its broad therapeutic faculties; he claimed that it should be introduced into European pharmacotherapy. In Wöhler's laboratory, cocaine was isolated from leaves by his pupil Alfred Niemann; later, Wilhelm Lossen refined and corrected Niemann's results. Narratives about medicinal drugs often streamline history into a story that starts with multiple meanings and impure matters and ends with well-defined substances, directed at clear-cut diseases and symptoms. In the case of Coca, however, the pure substance triggered no such process well into the 1880s, whereas the leaves continued to circulate as an exotic, pluripotent drug whose effects where miraculous and yet difficult to establish. PMID:20481059

  9. Shark tooth weapons from the 19th Century reflect shifting baselines in Central Pacific predator assemblies.

    PubMed

    Drew, Joshua; Philipp, Christopher; Westneat, Mark W

    2013-01-01

    The reefs surrounding the Gilbert Islands (Republic of Kiribati, Central Pacific), like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of this perturbation has been a reduction of the number of shark species present in their waters, even though sharks play an important in the economy and culture of the Gilbertese. Here we examine how shark communities changed over time periods that predate the written record in order to understand the magnitude of ecosystem changes in the Central Pacific. Using a novel data source, the shark tooth weapons of the Gilbertese Islanders housed in natural history museums, we show that two species of shark, the Spot-tail (Carcharhinus sorrah) and the Dusky (C. obscurus), were present in the islands during the last half of the 19(th) century but not reported in any historical literature or contemporary ichthyological surveys of the region. Given the importance of these species to the ecology of the Gilbert Island reefs and to the culture of the Gilbertese people, documenting these shifts in baseline fauna represents an important step toward restoring the vivid splendor of both ecological and cultural diversity.

  10. Dental health of the late 19th and early 20th century Khoesan.

    PubMed

    Botha, D; Steyn, M

    2015-06-01

    This paper presents the results of the dental analysis performed on a Khoesan skeletal sample representing the late 19th and early 20th century Cape Colony in southern Africa. Skeletal material from two European collections (Vienna and Paris) was selected to compile a total sample of 116 specimens. Dental pathology frequencies were calculated for caries (28.4%), antemortem tooth loss (37.9%), periapical abscesses (29.3%), periodontal disease (26.7%), calculus (44.0%) and impacted canines (4.3%). Attrition scores indicated that the group under study had an average rate of attrition compared to other southern African populations. Frequency and intensity data were compared to several other samples from both the pre-contact and contact phases by means of chi-squared analysis. The outcome of the study suggested that the group under study was most likely in a state of transition between a diet and lifestyle of hunting-and-gathering and agriculture. Results were also consistent with those of groups from a low socio-economic status.

  11. The impact of childhood sickness on adult socioeconomic outcomes: Evidence from late 19th century America

    PubMed Central

    Warren, John Robert; Knies, Laurie; Haas, Steven; Hernandez, Elaine M.

    2013-01-01

    We use family fixed-effects models to estimate the impact of childhood health on adult literacy, labor force outcomes, and marital status among pairs of white brothers observed as children in the 1880 U.S. Census and then as adults in the 1900–1930 Censuses. Given our focus on the 19th century, we observed a wider array of infectious, chronic, and traumatic health problems than is observed using data that are more recent; our results thus provide some insights into circumstances in modern developing countries where similar health problems are more frequently observed. Compared to their healthy siblings, sick brothers were less likely to be located (and thus more likely to be dead) 20–50 years after their 1880 enumeration. Sick brothers were also less likely to be literate, to have ever been married, and to have reported an occupation. However, among those with occupations, sick and healthy brothers tended to do similar kinds of work. We discuss the implications of our results for research on the impact of childhood health on socioeconomic outcomes in developed and developing countries. PMID:22809795

  12. Naming and Necessity: Sherborn’s Context in the 19th Century

    PubMed Central

    McOuat, Gordon

    2016-01-01

    Abstract By the late 19th Century, storms plaguing early Victorian systematics and nomenclature seemed to have abated. Vociferous disputes over radical renaming, the world-shaking clash of all-encompassing procrustean systems, struggles over centres of authority, and the issues of language and meaning had now been settled by the institution of a stable imperial museum and its catalogues, a set of rules for the naming of zoological objects, and a new professional class of zoologists. Yet, for all that tranquillity, the disputes simmered below the surface, re-emerging as bitter struggles over synonyms, trinomials, the subspecies category, the looming issues of the philosophy of scientific language, and the aggressive new American style of field biology – all pressed in upon the received practice of naming and classifying organisms and the threat of anarchy. In the midst rose an index. This paper will explore the context of CD Sherborn’s Index Animalium and those looming problems and issues which a laborious and comprehensive “index of nature” was meant to solve. PMID:26877652

  13. Polish dermatology in the 19th and the first half of the 20th centuries.

    PubMed

    Grzybowski, Andrzej

    2008-01-01

    The beginnings of Polish dermatology date back to the first half of the 19th century in Kraków. The first textbook of dermatology was written by Ludwik Bierkowski. Later the progress in the development of this field of medicine was due to Franciszek Krzyształowicz, Marian Grzybowski, Franciszek Walter, and Jan Alkiewicz. Krzyształowicz's most remarkable achievements were related to his studies of the Treponema pallidum of syphilis. Grzybowski's main contribution to international dermatology was the first description in the medical literature of a specific variant of keratoacanthoma, which has since then been called Grzybowski's eruptive keratoacanthoma or generalized eruptive keratoacanthoma - Grzybowski's variant. Alkiewicz described trachyonychia, or twenty-nail dystrophy, a disease that became well established in the dermatological literature; he also described the so-called transverse net in onychomycosis. Walter identified the syphilitic skin and bone lesions in some figures carved in the Veit Stoss's altar in Kraków, thus presenting the famous thesis of the non-American origin of syphilis in Europe. Considering all these achievements, it is the goal of this paper to review Polish contributions to international dermatology. PMID:18173613

  14. Ovariotomy for menstrual madness and premenstrual syndrome--19th century history and lessons for current practice.

    PubMed

    Studd, John

    2006-08-01

    Ovariotomy--the removal of normal ovaries, known as Battey's Operation--began in 1872 and became the fashionable treatment of menstrual madness, neurasthenia, nymphomania, masturbation and "all cases of insanity". This practice was supported by distinguished gynecologists and psychiatrists, becoming one of the great medical scandals of the 19th century. In modern times, if menstrual madness is considered to be premenstrual dysphoric disorder (PMDD), and ovariotomy, the surgical equivalent of ovulation suppression of GnRH analogues, it can be argued that the surgery would have been effective for this limited indication, although the side effects of long-term estrogen deficiency would have made the treatment unacceptable. Currently, the successful hormonal treatment of PMDD is one of suppression of ovulation and removal of the cyclical hormonal changes in the luteal phase, probably progesterone, which is the essential cause of PMDD. Such therapy would be by GnRH analogues, transdermal estradiol and, in a few cases, the surgical option of hysterectomy and bilateral salpingo-oophorectomy with adequate hormone replacement. A study of medical history can help us prevent the mistakes of over-enthusiasm but positive lessons can be learned.

  15. [The emergence of the Québec asylum in the 19th century.].

    PubMed

    Paradis, A

    1977-01-01

    This team of five philosophers analyses the 18th and 19th century Quebec discourse on the subject of insanity. The 18th century saw the insane excluded from social contact with the state recognizing only their indigence. They were relegated either to the "Loges", designed to expiate their sins since insanity was linked to an abuse of mind and body, or to prison for appropriate punishment, since madness was considered to lead to crime. But economic pressures produced by the growing number in indigents, including the mentally ill, led to the creation of the Beauport asylum in 1845. The authors then describe how the urban insane, marginal to both the French Canadian and English Canadian communities* were placed in private institutions and subjected to a system of profit maximization controlled by bourgeois physicians. This situation increased the distance between proprietors and occupants, and accounts for the lack of original discourse on the subject of insanity. In addition, the reasoning of the alienist physicians was without scientific foundation, taking root rather in the dominant industrial capitalist ideology. As for the content of the discourse, the Beauport physicians borrowed from moral treatment and restraint system notions, giving them a certain Quebec character.

  16. [Contribution of 19th-century religious congregations in the development of the nursing profession].

    PubMed

    Bezze, Sabrina; Manzoni, Edoardo; Di Mauro, Stefania

    2013-01-01

    The purpose of this historical research project is to examine the contribution of 19th-century religious congregations in the development of the nursing profession, based on the historical example of the Sisters of Charity of Sts. Bartolomea Capitanio and Vincenza Gerosa (or the Sisters of the Holy Child Mary). To this end, sixty three volumes were analysed, all taken from the historical archive of the Generalate of the Sisters of the Holy Child Mary in Milan, in via S. Sofia n.13, with the exception of just one, taken from the Braidense National Library, also in Milan. This research project has highlighted the sociological contribution provided by the Sisters of the Holy Child Mary to the professional nature of nursing, and to the development of the distinctive features of the nursing profession (Greenwood, 1980). All documentary sources were analysed in line with the Chabod historical research method (2006), and for their critical interpretation, a scheme of analysis was created. Two lines of investigation emerged from the data collected: the role of Sister Emilia Vinante as an expert with regard to the nursing profession, and the professional strategies promoted by FIRO (Federation of Italian Religious Nurses). Based on the conclusions of the research project, it may be stated that religious congregations contributed greatly to the nursing profession, leaving a decisive mark on the cultural and professional development of nurses.

  17. On the development of German beating-reed organ pipes during the 19th century

    NASA Astrophysics Data System (ADS)

    Braasch, Jonas

    2001-05-01

    In the 19th century organ literature, it is often claimed that German organ builders generally adapted the way of building their beating-reed pipes after being influenced by new developments from England and France. To investigate whether this hypothesis is true or false, the reed-pipe sounds of several German historic organs and an English organ by Henry Willis were measured and analyzed. The outcome of the analysis, however, cannot confirm the given hypothesis. Organ builders of the 18th century, such as Gottfried Silbermann for example, were already able to build beating-reed pipes similar in sound to the pipes that are used nowadays in Germany. It is noteworthy that Silbermann used closed shallots in some of his stops, although they are thought to be one of the main inventions in the English and French organ reforms. The use of higher wind pressures, which is also a main part of this reform, on the other hand, never became a common standard in Germany, as was the case for France and Great Britain.

  18. Placebos in 19th century medicine: a quantitative analysis of the BMJ

    PubMed Central

    Raicek, Jacqueline E; Stone, Bradley H

    2012-01-01

    Objective To provide the first quantitative data on the use of the term “placebo” in the 19th century. Design Computer search of BMJ’s archival database from January 1840 (the first issue) through December 1899 for uses of the words “placebo(s).” Grounded theory was used to categorise the implications of uses of the term. Results 71 citations contained the term “placebo(s).” Of these, 22 (31%) used the term to mean “no effect” or as a general pejorative term, 18 (25%) portrayed placebo treatment as permitting the unfolding of the natural history (the normal waxing and waning of illness), 14 (20%) described placebo as important to satisfy patients, 7 (10%) described it as fulfilling a physician’s performance role, 3 (4%) described its use to buy time, 3 (4%) described its use for financial gain, 2 (3%) used it in a manner similar to a placebo control, and only one implied that placebo could have a clinical effect. Only one citation mentioned telling the patient about his placebo treatment. Conclusion Nineteenth century physicians had diverse a priori assumptions about placebos. These findings remind us that contemporary medicine needs to use rigorous science to separate fact from its own beliefs concerning the “provision of care.” As in previous generations, ethical issues concerning placebos continue to challenge medicine. PMID:23249668

  19. [Development of the modern biological analogy concept in the 19th century].

    PubMed

    Bäumer, A

    1989-01-01

    At the beginning of the 19th century the term analogy was still synonymous with similarity, as for example in the case of Georges Cuvier. Exact criteria for determining analogy are first found in the work of Etienne Geoffroy Saint-Hilaire. Thereupon the English scientists Sharp MacLeay, William Swainson, John Obadiah Westwood and Edwin Strickland distinguished between analogy as correspondence between certain parts of the organism, i. e. only superficial resemblance, and affinity as an essential similarity in some remarkable aspects of form. Relying on these theories Richard Owen developed his theory of analogy ("a part which has the same function as another") and homology ("the same organ in different animals under every variety of form and function"). The criteria to distinguish between these two terms had to be modified and specified when the theory of evolution was developed by Charles Darwin. In the work of Thomas Henry Huxley, Ernst Haeckel and Carl Gegenbaur the modern biological term of analogy was developed, but at the same time it lost much of its importance and homology as a criterion for natural affinity became the central objective of further biological research.

  20. F/A-18 1/9th scale model tail buffet measurements

    NASA Technical Reports Server (NTRS)

    Martin, C. A.; Glaister, M. K.; Maclaren, L. D.; Meyn, L. A.; Ross, J.

    1991-01-01

    Wind tunnel tests were carried out on a 1/9th scale model of the F/A-18 at high angles of attack to investigate the characteristics of tail buffet due to bursting of the wing leading edge extension (LEX) vortices. The tests were carried out at the Aeronautical Research Laboratory low-speed wind tunnel facility and form part of a collaborative activity with NASA Ames Research Center, organized by The Technical Cooperative Program (TTCP). Information from the program will be used in the planning of similar collaborative tests, to be carried out at NASA Ames, on a full-scale aircraft. The program covered the measurement of unsteady pressures and fin vibration for cases with and without the wing LEX fences fitted. Fourier transform methods were used to analyze the unsteady data, and information on the spatial and temporal content of the vortex burst pressure field was obtained. Flow visualization of the vortex behavior was carried out using smoke and a laser light sheet technique.

  1. Shark tooth weapons from the 19th Century reflect shifting baselines in Central Pacific predator assemblies.

    PubMed

    Drew, Joshua; Philipp, Christopher; Westneat, Mark W

    2013-01-01

    The reefs surrounding the Gilbert Islands (Republic of Kiribati, Central Pacific), like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of this perturbation has been a reduction of the number of shark species present in their waters, even though sharks play an important in the economy and culture of the Gilbertese. Here we examine how shark communities changed over time periods that predate the written record in order to understand the magnitude of ecosystem changes in the Central Pacific. Using a novel data source, the shark tooth weapons of the Gilbertese Islanders housed in natural history museums, we show that two species of shark, the Spot-tail (Carcharhinus sorrah) and the Dusky (C. obscurus), were present in the islands during the last half of the 19(th) century but not reported in any historical literature or contemporary ichthyological surveys of the region. Given the importance of these species to the ecology of the Gilbert Island reefs and to the culture of the Gilbertese people, documenting these shifts in baseline fauna represents an important step toward restoring the vivid splendor of both ecological and cultural diversity. PMID:23573214

  2. ["Fabulous things". Drug narratives about coca and cocaine in the 19th century].

    PubMed

    Wahrig, Bettina

    2009-12-01

    This contribution focuses on the history of Coca leaves and Cocaine in the second half of 19th century Europe. Even though, to date, no direct link has been established between the activities of the Milano physician Paolo Mantegazza, and the Göttingen chemist Friedrich Wöhler, it is not a mere coincidence that both published their findings in the same year, namely, 1859. Mantegazza authored the first treatise claiming that Coca had psychoactive qualities and touted its broad therapeutic faculties; he claimed that it should be introduced into European pharmacotherapy. In Wöhler's laboratory, cocaine was isolated from leaves by his pupil Alfred Niemann; later, Wilhelm Lossen refined and corrected Niemann's results. Narratives about medicinal drugs often streamline history into a story that starts with multiple meanings and impure matters and ends with well-defined substances, directed at clear-cut diseases and symptoms. In the case of Coca, however, the pure substance triggered no such process well into the 1880s, whereas the leaves continued to circulate as an exotic, pluripotent drug whose effects where miraculous and yet difficult to establish.

  3. Dental health of the late 19th and early 20th century Khoesan.

    PubMed

    Botha, D; Steyn, M

    2015-06-01

    This paper presents the results of the dental analysis performed on a Khoesan skeletal sample representing the late 19th and early 20th century Cape Colony in southern Africa. Skeletal material from two European collections (Vienna and Paris) was selected to compile a total sample of 116 specimens. Dental pathology frequencies were calculated for caries (28.4%), antemortem tooth loss (37.9%), periapical abscesses (29.3%), periodontal disease (26.7%), calculus (44.0%) and impacted canines (4.3%). Attrition scores indicated that the group under study had an average rate of attrition compared to other southern African populations. Frequency and intensity data were compared to several other samples from both the pre-contact and contact phases by means of chi-squared analysis. The outcome of the study suggested that the group under study was most likely in a state of transition between a diet and lifestyle of hunting-and-gathering and agriculture. Results were also consistent with those of groups from a low socio-economic status. PMID:25882044

  4. [A new political contribution to medicine: homeopathy in 19th century Spain].

    PubMed

    Albarracin Teulon, A

    1993-01-01

    The author has sumarized the role of well known 19th century doctors, Thackray, Villermé, Chadwick and especially Virchow (whose socio-medical works are related in detail), in the influence of political ideas on Medicine. As a new contribution to this subject the author informs us of the participation or a Spanish homeopathic doctor in this task. Anastasio García López (1821-1897), was influenced by the works of Charles Fourier, whose doctrine was spreading throughout Spain at that time. García López aplied the sociological concepts of the French utopian philosopher to his idea of homeopaty. A review is made of how Fourierism penetrated and became implanted in Spain and the mark it left on Hahnemann is analized using the "passionate attraction" concept and the ideas of social constriction and violence. García López believed that Hahnemann was attempting to free therapeutics from the yoke of attacking symptoms, emphasizing the affinities of the illness with the cure. Finally, this influence is demostrated in all the activitires of this Spanish doctor, politican, spiritualist, mason and hydrologist of renown.

  5. Shark Tooth Weapons from the 19th Century Reflect Shifting Baselines in Central Pacific Predator Assemblies

    PubMed Central

    Drew, Joshua; Philipp, Christopher; Westneat, Mark W.

    2013-01-01

    The reefs surrounding the Gilbert Islands (Republic of Kiribati, Central Pacific), like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of this perturbation has been a reduction of the number of shark species present in their waters, even though sharks play an important in the economy and culture of the Gilbertese. Here we examine how shark communities changed over time periods that predate the written record in order to understand the magnitude of ecosystem changes in the Central Pacific. Using a novel data source, the shark tooth weapons of the Gilbertese Islanders housed in natural history museums, we show that two species of shark, the Spot-tail (Carcharhinus sorrah) and the Dusky (C. obscurus), were present in the islands during the last half of the 19th century but not reported in any historical literature or contemporary ichthyological surveys of the region. Given the importance of these species to the ecology of the Gilbert Island reefs and to the culture of the Gilbertese people, documenting these shifts in baseline fauna represents an important step toward restoring the vivid splendor of both ecological and cultural diversity. PMID:23573214

  6. Factors influencing the recession rate of Niagara Falls since the 19th century

    NASA Astrophysics Data System (ADS)

    Hayakawa, Yuichi S.; Matsukura, Yukinori

    2009-09-01

    The rate of recession of Niagara Falls (Horseshoe and American Falls) in northeastern North America has been documented since the 19th century; it shows a decreasing trend from ca. 1 m y - 1 a century ago to ca. 0.1 m y - 1 at present. Reduction of the flow volume in the Niagara River due to diversion into bypassing hydroelectric schemes has often been taken to be the factor responsible, but other factors such as changes in the waterfall shape could play a role and call for a quantitative study. Here, we examine the effect of physical factors on the historically varying recession rates of Niagara Falls, using an empirical equation which has previously been proposed based on a non-dimensional multiparametric model which incorporates flow volume, waterfall shape and bedrock strength. The changes in recession rates of Niagara Falls in the last century are successfully modeled by this empirical equation; these changes are caused by variations in flow volume and lip length. This result supports the validity of the empirical equation for waterfalls in rivers carrying little transported sediment. Our analysis also suggests that the decrease in the recession rate of Horseshoe Falls is related to both artificial reduction in river discharge and natural increase in waterfall lip length, whereas that of American Falls is solely due to the reduction in flow volume.

  7. A New Challenge to Solar Dynamo Models from Helioseismic Observations: The Latitudinal Dependence of the Progression of the Solar Cycle

    NASA Astrophysics Data System (ADS)

    Simoniello, R.; Tripathy, S. C.; Jain, K.; Hill, F.

    2016-09-01

    The onset of the solar cycle at mid-latitudes, the slowdown in the drift of sunspots toward the equator, the tail-like attachment, and the overlap of successive cycles at the time of minimum activity are delicate issues in models of the αΩ dynamo wave and the flux transport dynamo. Very different parameter values produce similar results, making it difficult to understand the origin of the properties of these solar cycles. We use helioseismic data from the Global Oscillation Network Group to investigate the progression of the solar cycle as observed in intermediate-degree global p-mode frequency shifts at different latitudes and subsurface layers, from the beginning of solar cycle 23 up to the maximum of the current solar cycle. We also analyze those for high-degree modes in each hemisphere obtained through the ring-diagram technique of local helioseismology. The analysis highlights differences in the progression of the cycle below 15° compared to higher latitudes. While the cycle starts at mid-latitudes and then migrates equatorward/poleward, the sunspot eruptions of the old cycle are still ongoing below 15° latitude. This prolonged activity causes a delay in the onset of the cycle and an overlap of successive cycles, whose extent differs in the two hemispheres. Then the activity level rises faster, reaching a maximum characterized by a single-peak structure as opposed to the double peak at higher latitudes. Afterwards the descending phase shows up with a slower decay rate. The latitudinal properties of the progression of the solar cycle highlighted in this study provide useful constraints for discerning among the multitude of solar dynamo models.

  8. Source of a Prominent Poleward Surge During Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Yeates, A. R.; Baker, D.; van Driel-Gesztelyi, L.

    2015-11-01

    As an observational case study, we consider the origin of a prominent poleward surge of leading polarity, visible in the magnetic butterfly diagram during Solar Cycle 24. A new technique is developed for assimilating individual regions of strong magnetic flux into a surface-flux transport model. By isolating the contribution of each of these regions, the model shows the surge to originate primarily in a single high-latitude activity group consisting of a bipolar active region present in Carrington Rotations 2104 - 05 (November 2010 - January 2011) and a multipolar active region in Rotations 2107 - 08 (February - April 2011). This group had a strong axial dipole moment opposed to Joy's law. On the other hand, the modelling suggests that the transient influence of this group on the butterfly diagram will not be matched by a large long-term contribution to the polar field because it is located at high latitude. This is in accordance with previous flux-transport models.

  9. An Epistemological Approach to French Syllabi on Human Origins during the 19th and 20th Centuries

    ERIC Educational Resources Information Center

    Quessada, Marie-Pierre; Clement, Pierre

    2007-01-01

    This study focuses on how human origins were taught in the French Natural Sciences syllabuses of the 19th and 20th centuries. We evaluate the interval between the publication of scientific concepts and their emergence in syllabuses, i.e., didactic transposition delay (DTD), to determine how long it took for scientific findings pertaining to our…

  10. How To Dance through Time. Volume VI: A 19th Century Ball--The Charm of Group Dances. [Videotape].

    ERIC Educational Resources Information Center

    Teten, Carol

    This 48-minute VHS videotape is the sixth in a series of "How To Dance Through Time" videos. It shows the festivity of the 19th century group dances, enabling the viewer to plan and participate in the elegant opening to the ball, a refined square dance, and flirtatious Cotillion dancing games. Professional dancers demonstrate the patterns with…

  11. How To Dance through Time. Volume I: The Romance of Mid-19th Century Couple Dances. Beginning Level. [Videotape].

    ERIC Educational Resources Information Center

    Teten, Carol

    This 35-minute VHS videotape is the first in a series of "How To Dance Through Time" videos. It provides how-to instructions to help beginning dancers learn the mid-19th century ballroom couple dances. It introduces dancers to the basic steps, which accompany the romantic dance music of the past. Each dance segment is introduced by a brief…

  12. Body mass, wealth, and inequality in the 19th century: joining the debate surrounding equality and health.

    PubMed

    Carson, Scott Alan

    2013-01-01

    We explore relationships among BMI variation, wealth, and inequality in the 19th century US. There was an inverse relationship between BMI and average state-level wealth and a small, inverse relationship with wealth inequality. After controlling for wealth and inequality, farmers had greater BMI values than workers in other occupations, and blacks had greater BMI values because of nutritional deprivation in utero.

  13. Self-Help Medical Literature in 19th-Century Canada and the Rhetorical Convention of Plain Language.

    ERIC Educational Resources Information Center

    Connor, Jennifer J.

    1994-01-01

    Examines self-help medical literature in 19th-century Canada. Shows that while authors repeatedly called for "plain" language in contrast to mysterious terminology employed by medical practitioners, comparison of their style with that of medical textbook authors reveals few real differences. Concludes that the posture adopted by Canadian self-help…

  14. The Struggle To Survive: Work for Racial Ethnic Women in the 18th- and 19th-Century United States.

    ERIC Educational Resources Information Center

    Higginbotham, Elizabeth

    The work situations of Black, Mexican American, and Chinese immigrant women in 18th- and 19th-century United States are explored. Generally, when engaged in agricultural work, all ethnic people were considered units of labor. However, because the slave owner needed to perpetuate his property, Black women were allowed lower rates of production when…

  15. Physics education in the Greek community schools of Istanbul (19th century). Scientific instruments and experiments in electrostatics

    NASA Astrophysics Data System (ADS)

    Lazos, Panagiotis; Vlahakis, George N.

    2016-03-01

    The Greek schools operating in Istanbul date back to the 19th century. These schools have noteworthy collections of old scientific instruments that were used in teaching experimental physics. Amongst them, more outstanding are the scientific instruments used in demonstrating electrostatics. This paper briefly presents the equipment, focuses on exceptional scientific instruments and attempts to illuminate certain aspects in teaching the natural sciences.

  16. Founding of Compulsory Civil Education According to the Education Acts from Second Half of the 19th Century

    ERIC Educational Resources Information Center

    Lukaš, Mirko

    2012-01-01

    Records of education in Croatia occur very soon after the settlement of Croats in this area. It is tied to 9th century and Duke Trpimir. Initial steps of education were not legally bounded nor the school was obligatory. In the second half of the 19th century, more precisely in 1871, with the First Education Act education becomes obligatory. Using…

  17. The Educational Utilization of Elements of the History of Natural Sciences (19th Century): Highlighting the Cognitive Continuity with Antiquity

    ERIC Educational Resources Information Center

    Maniati, Helen A.

    2005-01-01

    In the current paper, the reasons why the late 19th century Greek university community of natural scientists used elements from the History of Natural sciences which refer exclusively to ancient Greek science, and the consequences of such a choice are evaluated. Emphasis will be given to the speech delivered by the Dean, Professor of Chemistry, A.…

  18. The use of Congreve-type war Rockets by the Spanish in the 19th century: A chronology

    NASA Technical Reports Server (NTRS)

    Sancho, P. M.

    1977-01-01

    A yearly account of military uses, by the Spanish, of Congreve war rockets is given, from the year 1810 until 1895. Events prior to the 19th century are also recorded which include the use of rockets against the Moors of Valencia and documentation, from literature of that period, relating to rocket applications.

  19. Threads of Change in 19th Century American Literature: A Language Arts Unit for Grades 7-9.

    ERIC Educational Resources Information Center

    Crossett, Becky F.; And Others

    This unit of study for junior-high level high-ability language arts students explores five themes in 19th century American history through literature of the times: romanticism, transcendentalism, abolitionism, industrialism, and feminism. Each of the five "isms" has its own "literature box" that contains appropriate documents to serve as a…

  20. Findings from the Survey of Participants of the 19th Annual National Conference of Black Physics Students

    ERIC Educational Resources Information Center

    Dollison, Julius; Neuschatz, Michael

    2005-01-01

    On the weekend of February 3-6, the University of Chicago and Argonne National Laboratory in Illinois hosted the 2005 National Conference of Black Physics Students, marking the 19th consecutive year that the Conference has provided African American physics students with the unique opportunity to meet and network with counterparts from all across…

  1. The Case for Consolidation: Our 19th-Century Model of Governance Is a Formula for Mediocrity

    ERIC Educational Resources Information Center

    Amdursky, Saul

    2004-01-01

    We need fewer public libraries with greater dependence. Here at the beginning of the 21st century, public libraries are still saddled with a 19th-century model of government. They are far too beholden to governing authorities, usually municipal or county governments, for their financial sustenance. This is a formula for mediocrity. "Local control"…

  2. Solar wind interaction with the Martian upper atmosphere: Crustal field orientation, solar cycle, and seasonal variations

    NASA Astrophysics Data System (ADS)

    Dong, Chuanfei; Bougher, Stephen W.; Ma, Yingjuan; Toth, Gabor; Lee, Yuni; Nagy, Andrew F.; Tenishev, Valeriy; Pawlowski, Dave J.; Combi, Michael R.; Najib, Dalal

    2015-09-01

    A comprehensive study of the solar wind interaction with the Martian upper atmosphere is presented. Three global models: the 3-D Mars multifluid Block Adaptive Tree Solar-wind Roe Upwind Scheme MHD code (MF-MHD), the 3-D Mars Global Ionosphere Thermosphere Model (M-GITM), and the Mars exosphere Monte Carlo model Adaptive Mesh Particle Simulator (M-AMPS) were used in this study. These models are one-way coupled; i.e., the MF-MHD model uses the 3-D neutral inputs from M-GITM and the 3-D hot oxygen corona distribution from M-AMPS. By adopting this one-way coupling approach, the Martian upper atmosphere ion escape rates are investigated in detail with the combined variations of crustal field orientation, solar cycle, and Martian seasonal conditions. The calculated ion escape rates are compared with Mars Express observational data and show reasonable agreement. The variations in solar cycles and seasons can affect the ion loss by a factor of ˜3.3 and ˜1.3, respectively. The crustal magnetic field has a shielding effect to protect Mars from solar wind interaction, and this effect is the strongest for perihelion conditions, with the crustal field facing the Sun. Furthermore, the fraction of cold escaping heavy ionospheric molecular ions [(O2+ and/or O2+)/Total] are inversely proportional to the fraction of the escaping (ionospheric and corona) atomic ion [O+/Total], whereas O2+ and O2+ ion escape fractions show a positive linear correlation since both ion species are ionospheric ions that follow the same escaping path.

  3. Properties of Magnetic Tongues over a Solar Cycle

    NASA Astrophysics Data System (ADS)

    Poisson, Mariano; Démoulin, Pascal; López Fuentes, Marcelo; Mandrini, Cristina H.

    2016-08-01

    The photospheric spatial distribution of the main magnetic polarities of bipolar active regions (ARs) present during their emergence deformations are known as magnetic tongues. They are attributed to the presence of twist in the toroidal magnetic-flux tubes that form the ARs. The aim of this article is to study the twist of newly emerged ARs from the evolution of magnetic tongues observed in photospheric line-of-sight magnetograms. We apply the procedure described by Poisson et al. ( Solar Phys. 290, 727, 2015a) to ARs observed over the full Solar Cycle 23 and the beginning of Cycle 24. Our results show that the hemispherical rule obtained using the tongues as a proxy of the twist has a weak sign dominance (53 % in the southern hemisphere and 58 % in the northern hemisphere). By defining the variation of the tongue angle, we characterize the strength of the magnetic tongues during different phases of the AR emergence. We find that there is a tendency of the tongues to be stronger during the beginning of the emergence and to become weaker as the AR reaches its maximum magnetic flux. We compare this evolution with the emergence of a toroidal flux-rope model with non-uniform twist. The variety of evolution of the tongues in the analyzed ARs can only be reproduced when using a broad range of twist profiles, in particular having a large variety of twist gradients in the direction vertical to the photosphere. Although the analytical model used is a special case, selected to minimize the complexity of the problem, the results obtained set new observational constraints to theoretical models of flux-rope emergence that form bipolar ARs.

  4. The high energetic particles released during the decline phases of last five solar cycles

    NASA Astrophysics Data System (ADS)

    Hady, A. A., II

    2014-12-01

    During the decline phases of the last five solar cycles, new peak has appeared releasing high energetic particles. During October 2003 (so-called Halloween storms), a sudden increase of the solar activity occurred during the decline phase which has bigger than that occurred during the main peak of that Solar cycle 23. The same situation was repeated again for the solar cycle 24, during its decline phase, giving a new peak during January 2014 and release high energetic particles, which was bigger than that occurred during the mean peak of cycle 24. This means that the solar cycles starting from the cycle 20 have two peaks, the second peak always producing higher energetic flares which affects the Earth's magnetic field. The same situation happened in the cycles 21, and 22, but with lower release of energetic particle, compared with cycles 23 and 24. We will do descriptive studies of these events, according to data analysis, and compare the results. Keywords: Solar cycles; solar activities; solar energetic particles, Halloween storms, January 2014 storms.

  5. Sources of Geomagnetic Activity during Nearly Three Solar Cycles (1972-2000)

    NASA Technical Reports Server (NTRS)

    Richardson, I. G.; Cane, H. V.; Cliver, E. W.; White, Nicholas E. (Technical Monitor)

    2002-01-01

    We examine the contributions of the principal solar wind components (corotating highspeed streams, slow solar wind, and transient structures, i.e., interplanetary coronal mass ejections (CMEs), shocks, and postshock flows) to averages of the aa geomagnetic index and the interplanetary magnetic field (IMF) strength in 1972-2000 during nearly three solar cycles. A prime motivation is to understand the influence of solar cycle variations in solar wind structure on long-term (e.g., approximately annual) averages of these parameters. We show that high-speed streams account for approximately two-thirds of long-term aa averages at solar minimum, while at solar maximum, structures associated with transients make the largest contribution (approx. 50%), though contributions from streams and slow solar wind continue to be present. Similarly, high-speed streams are the principal contributor (approx. 55%) to solar minimum averages of the IMF, while transient-related structures are the leading contributor (approx. 40%) at solar maximum. These differences between solar maximum and minimum reflect the changing structure of the near-ecliptic solar wind during the solar cycle. For minimum periods, the Earth is embedded in high-speed streams approx. 55% of the time versus approx. 35% for slow solar wind and approx. 10% for CME-associated structures, while at solar maximum, typical percentages are as follows: high-speed streams approx. 35%, slow solar wind approx. 30%, and CME-associated approx. 35%. These compositions show little cycle-to-cycle variation, at least for the interval considered in this paper. Despite the change in the occurrences of different types of solar wind over the solar cycle (and less significant changes from cycle to cycle), overall, variations in the averages of the aa index and IMF closely follow those in corotating streams. Considering solar cycle averages, we show that high-speed streams account for approx. 44%, approx. 48%, and approx. 40% of the solar

  6. Solar cycle lengths and climate: A reference revisited

    NASA Astrophysics Data System (ADS)

    Laut, Peter; Gundermann, Jesper

    2000-12-01

    An article published by Friis-Christensen and Lassen [1991] appeared to indicate an association between solar cycle lengths (SCLs) and climate. It attracted worldwide attention and has since been extensively referred to. We here present an updated analysis using a recent temperature reconstruction with the time period of comparison considerably expanded. The correlation is found to be weak. In the light of this new result we analyze the question how the article by Friis-Christensen and Lassen was able to create the impression of a `strikingly good agreement,' as the authors described it. We show that the main reason is an unacceptable mixing of filtered and nonfiltered data in the graphical representation. Hereby, an artificial agreement of the solar data with the global warming since 1970 was established. The article by Friis-Christensen and Lassen has created and still creates confusion both in scientific and public discussions on climate change. We have therefore found it relevant to deliver the present analysis.

  7. Peaks of solar cycles affect the gender ratio.

    PubMed

    Davis, George E; Lowell, Walter E

    2008-12-01

    In this study, we report that the gender ratio (GR) at death [where GR=(N(males)/N(males)+N(females))] of those born (and likely conceived) in solar cycle peaks (about a 3-year period occurring on average every approximately 11 years), is inversely related to mean male age at death; e.g., the higher the GR(at death) the lower the mean lifespan, while the GR(at death) of those born in non-peak years has no relation to mean male lifespan. Although changes in the GR are small and may be of little clinical significance, the GR is a sensitive indicator of environmental effects, and therefore is pertinent to epigenetics. This paper supports the hypothesis that solar radiation, probably in the ultraviolet spectrum, by some manner interacts with chromosomal DNA (genes) and produces the genetic variety that not only fosters adaptation, but also produces the diseases that reduce lifespan. This paper also proposes that sunlight is more effective in modifying genomes at the time of conception than later in gestation or infancy. Referring to the work of others, this study also reveals that geographic latitude also affects the GR, suggesting that the variation in light is probably as important as the intensity of light in modifying genomes. This study finds that men sustain more genetic variation, producing 28% more disease than women, as well as a 2% decrease in GR from birth to death, and a shorter life (in Maine) by 7 years. PMID:18755551

  8. Analysis of Polar Reversals of Solar Cycle 22 and 23

    NASA Astrophysics Data System (ADS)

    Ettinger, Sophie

    2015-01-01

    We study the relationship between polar field reversals and decayed active region magnetic flux. Photospheric active region flux is dispersed by differential rotation and turbulent diffusion, and is transported poleward by meridional flows and diffusion. We investigate in detail the relationship between the transport of decayed active region flux to high latitudes and changes in the polar field strength, including reversals in the magnetic polarity at the poles. By means of stack plots of low- and high-latitude slices of synoptic magnetograms, one to three activity complexes (systems of active regions) were identified in each reversal as the main cause of polar field reversals in each cycle. The poleward transport of large quantities of decayed lagging-polarity flux from these complexes was found to correlate well in time with the polar field changes. In each case significant latitudinal displacements were found between the positive and negative flux centroids of the complexes, consistent with Joy's law bipole tilt with lagging-polarity flux located poleward of leading-polarity flux. This result indicates the importance of the Joy's law tilt and consequent high-latitude polarity bias in polar reversals.This work is carried out through the National Solar Observatory Summer Research Assistantship (SRA) Program. The National Solar Observatory is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the National Science Foundation.

  9. Solar Cycle Variations of the Occurrence of Coronal Type III Radio Bursts and a New Solar Activity Index

    NASA Astrophysics Data System (ADS)

    Lobzin, V. V.; Cairns, I. H.; Robinson, P. A.

    2011-12-01

    The results of studies of solar cycle variations of the occurrence rate of coronal type III radio bursts are presented. The radio spectra are provided by the Learmonth Solar Radio Observatory (Western Australia), part of the USAF Radio Solar Telescope Network (RSTN). It is found that the occurrence rate of type III bursts strongly correlates with solar activity. However, the profiles for the smoothed type III burst occurrence rate differ considerably from those for the sunspot number, 10.7 cm solar radio flux, and solar flare index. The type III burst occurrence rate (T3BOR) is proposed as a new index of solar activity. T3BOR provides complementary information about solar activity and should be useful in different studies including solar cycle predictions and searches for different periodicities in solar activity. This index can be estimated from daily results of the Automated Radio Burst Identification System (ARBIS). Access to data from other RSTN sites will allow processing 24-hour radio spectra in near-real time and estimating true daily values of this index. It is also shown that coronal type III bursts can even occur when there are no visible sunspots on the Sun. However, no evidence is found that the bursts are not associated with active regions. It is also concluded that the type III burst productivity of active regions exhibits solar cycle variations.

  10. SOLAR CYCLE VARIATIONS OF THE OCCURRENCE OF CORONAL TYPE III RADIO BURSTS AND A NEW SOLAR ACTIVITY INDEX

    SciTech Connect

    Lobzin, Vasili; Cairns, Iver H.; Robinson, Peter A.

    2011-07-20

    This Letter presents the results of studies of solar cycle variations of the occurrence rate of coronal type III radio bursts. The radio spectra are provided by the Learmonth Solar Radio Observatory (Western Australia), part of the USAF Radio Solar Telescope Network (RSTN). It is found that the occurrence rate of type III bursts strongly correlates with solar activity. However, the profiles for the smoothed type III burst occurrence rate differ considerably from those for the sunspot number, 10.7 cm solar radio flux, and solar flare index. The type III burst occurrence rate (T3BOR) is proposed as a new index of solar activity. T3BOR provides complementary information about solar activity and should be useful in different studies including solar cycle predictions and searches for different periodicities in solar activity. This index can be estimated from daily results of the Automated Radio Burst Identification System. Access to data from other RSTN sites will allow processing 24 hr radio spectra in near-real time and estimating true daily values of this index. It is also shown that coronal type III bursts can even occur when there are no visible sunspots on the Sun. However, no evidence is found that the bursts are not associated with active regions. It is also concluded that the type III burst productivity of active regions exhibits solar cycle variations.

  11. Why is the Sun No Longer Accelerating Particles to High Energy in Solar Cycle 24?

    NASA Astrophysics Data System (ADS)

    Mewaldt, R. A.; Cohen, C. M.; Li, G.; Mason, G. M.; Smith, C. W.; von Rosenvinge, T. T.; Vourlidas, A.

    2015-12-01

    Why is the Sun No Longer Accelerating Particles to High Energy in Solar Cycle 24?Measurements by ACE, STEREO, and GOES show that the number of large Solar Energetic Particle (SEP) events in solar cycle 24 is reduced by a factor of ~2 compared to this point of solar cycle 23, while the fluences of >10 MeV/nuc ions from H to Fe are reduced by factors ranging from ~4 to ~10. Compared to solar Cycle 22 and 23, the fluence of >100 MeV protons is reduced by factors of ~7 to ~10 in the current cycle. A common element of these observations is that the observed Cycle-24 energy spectra have "breaks" that suddenly steepen 2 to 4 times lower in energy/nucleon than in Cycle 23. We investigate the origin of these cycle-to-cycle spectral differences by evaluating possible factors that control the maximum energy of CME-shock-accelerated particles in the two cycles, including seed-particle densities of suprathermal ions, the interplanetary magnetic field strength and turbulence level, and properties of the associated CMEs. The effect of these conditions will be evaluated in the context of existing SEP acceleration models by comparing SEP data with simulations and with analytic evaluations of the maximum kinetic energy to which CME shocks can accelerate solar energetic ions from H to Fe. Understanding the properties that control the maximum kinetic energy of CME-shock accelerated particles has important implications for predicting future solar activity.

  12. Reading The Sun: A Three Dimensional Visual Model of The Solar Environment During Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Carranza-fulmer, T. L.; Moldwin, M.

    2014-12-01

    The sun is a powerful force that has proven to our society that it has a large impact on our lives. Unfortunately, there is still a lack of awareness on how the sun is capable of affecting Earth. The over all idea of "Reading The Sun" installation is to help demonstrate how the sun impacts the Earth, by compiling various data sources from satellites (SOHO, SDO, and STERO) with solar and solar wind models (MAS and ENLIL) to create a comprehensive three dimensional display of the solar environment. It focuses on the current solar maximum of solar cycle 24 and a CME that impacted Earth's magnetic field on February 27, 2014, which triggered geomagnetic storms around the Earth's poles. The CME was an after-effect of a class X4.9 solar flare, which was released from the sun on February 25, 2014. "Reading The Sun" is a 48" x 48" x 48" hanging model of the sun with color coded open opposing magnetic field lines along with various layers of the solar atmosphere, the heliospheric current sheet, and the inner planets. At the center of the xyz axis is the sun with the open magnetic field lines and the heliospheric current sheet permeating inner planetary space. The xyz axes are color coded to represent various types of information with corresponding visual images for the viewer to be able to read the model. Along the z-axis are three colors (yellow, orange, and green) that represent the different layers of the solar atmosphere (photosphere, chromosphere, and corona) that correspond to three satellite images in various spectrums related to a CME and Solar Flare and the xy-plane shows where the inner planets are in relation to the sun. The exhibit in which "Reading The Sun "is being displayed is called, The Rotation of Language at the Wheather Again Gallery in Rockaway, New York. The intent of the exhibit is to both celebrate as well as present a cautionary tale on the ability of human language to spark and ignite the individual and collective imagination towards an experience

  13. A STATISTICAL STUDY OF SOLAR ELECTRON EVENTS OVER ONE SOLAR CYCLE

    SciTech Connect

    Wang Linghua; Lin, R. P.; Krucker, Saem; Mason, Glenn M.

    2012-11-01

    We survey the statistical properties of 1191 solar electron events observed by the WIND 3DP instrument from <1 keV to {approx}>300 keV for a solar cycle (1995 through 2005). After taking into account times of high background, the corrected occurrence frequency of solar electron events versus peak flux exhibits a power-law distribution over three orders of magnitude with exponents between -1.0 and -1.6 for different years, comparable to the frequency distribution of solar proton events, microflares, and coronal mass ejections (CMEs), but significantly flatter than that of soft X-ray (SXR) flares. At 40 keV (2.8 keV), the integrated occurrence rate above {approx}0.29 ({approx}330) cm{sup -2} s{sup -1} sr{sup -1} keV{sup -1} near 1 AU is {approx}1000 year{sup -1} ({approx}600 year{sup -1}) at solar maximum and {approx}35 year{sup -1} ({approx}25 year{sup -1}) at solar minimum, about an order of magnitude larger than the observed occurrence rate. We find these events typically extend over {approx}45 Degree-Sign in longitude, implying the occurrence rate over the whole Sun is {approx}10{sup 4} year{sup -1} near solar maximum. The observed solar electron events have a 98.75% association with type III radio bursts, suggesting all type III bursts may be associated with a solar electron event. They have a close ({approx}76%) association with the presence of low-energy ({approx}0.02-2 MeV nucleon{sup -1}), {sup 3}He-rich ({sup 3}He/{sup 4}He {>=} 0.01) ion emissions measured by the ACE ULEIS instrument. For these electron events, only {approx}35% are associated with a reported GOES SXR flare, but {approx}60% appear to be associated with a CME, with {approx}50% of these CMEs being narrow. These electrons are often detected down to below 1 keV, indicating a source high in the corona.

  14. Cycle Evaluations of Reversible Chemical Reactions for Solar Thermochemical Energy Storage in Support of Concentrating Solar Power Generation Systems

    SciTech Connect

    Krishnan, Shankar; Palo, Daniel R.; Wegeng, Robert S.

    2010-07-25

    The production and storage of thermochemical energy is a possible route to increase capacity factors and reduce the Levelized Cost of Electricity from concentrated solar power generation systems. In this paper, we present the results of cycle evaluations for various thermochemical cycles, including a well-documented ammonia closed-cycle along with open- and closed-cycle versions of hydrocarbon chemical reactions. Among the available reversible hydrocarbon chemical reactions, catalytic reforming-methanation cycles are considered; specifically, various methane-steam reforming cycles are compared to the ammonia cycle. In some cases, the production of an intermediate chemical, methanol, is also included with some benefit being realized. The best case, based on overall power generation efficiency and overall plant capacity factor, was found to be an open cycle including methane-steam reforming, using concentrated solar energy to increase the chemical energy content of the reacting stream, followed by combustion to generate heat for the heat engine.

  15. Near-Earth Solar Wind Flows and Related Geomagnetic Activity During more than Four Solar Cycles (1963-2011)

    NASA Technical Reports Server (NTRS)

    Richardson, Ian G.; Cane, Hilary V.

    2012-01-01

    In past studies, we classified the near-Earth solar wind into three basic flow types based on inspection of solar wind plasma and magnetic field parameters in the OMNI database and additional data (e.g., geomagnetic indices, energetic particle, and cosmic ray observations). These flow types are: (1) High-speed streams associated with coronal holes at the Sun, (2) Slow, interstream solar wind, and (3) Transient flows originating with coronal mass ejections at the Sun, including interplanetary coronal mass ejections and the associated upstream shocks and post-shock regions. The solar wind classification in these previous studies commenced with observations in 1972. In the present study, as well as updating this classification to the end of 2011, we have extended the classification back to 1963, the beginning of near-Earth solar wind observations, thereby encompassing the complete solar cycles 20 to 23 and the ascending phase of cycle 24. We discuss the cycle-to-cycle variations in near-Earth solar wind structures and l1e related geomagnetic activity over more than four solar cycles, updating some of the results of our earlier studies.

  16. PREFACE: 19th International Conference on Electron Dynamics in Semiconductors, Optoelectronics and Nanostructures (EDISON'19)

    NASA Astrophysics Data System (ADS)

    González, T.; Martín-Martínez, M. J.; Mateos, J.

    2015-10-01

    The 19th International Conference on Electron Dynamics in Semiconductors, Optoelectronics and Nanostructures (EDISON'19) was held at the Hospedería Fonseca (Universidad de Salamanca, Spain), on 29 June - 2 July, 2015, and was organized by the Electronics Area from the University of Salamanca. The Conference is held biannually and covers the recent progress in the field of electron dynamics in solid-state materials and devices. This was the 19th meeting of the international conference series formerly named Hot Carriers in Semiconductors (HCIS), first held in Modena in 1973. In the edition of 1997 in Berlin the name of the conference changed to International Conference on Nonequilibrium Carrier Dynamics in Semiconductors, keeping the same acronym, HCIS; and finally in the edition of Montpellier in 2009 the name was again changed to the current one, International Conference on Electron Dynamics in Semiconductors, Optoelectronics and Nanostructures (EDISON). The latest editions took place in Santa Barbara, USA, in 2011 and Matsue, Japan, in 2013. Research work on electron dynamics involves quite different disciplines, and requires both fundamental and technological scientific efforts. Attendees to the conference come mostly from academic institutions, belonging to both theoretical and experimental groups working in a variety of fields, such as solid-state physics, electronics, optics, electrical engineering, material science, laser physics, etc. In this framework, events like the EDISON conference become a basic channel for the progress in the field. Here, researchers working in different areas can meet, present their latest advances and exchange their ideas. The program of EDISON'19 included 13 invited papers, 61 oral contributions and 73 posters. These contributions originated from scientists in more than 30 different countries. The Conference gathered 140 participants, coming from 24 different countries, most from Europe, but also with a significant participation

  17. [Eventful life stories. Members of student fraternities persecuted in Silesia in the early 19th century].

    PubMed

    Schmidt, Walter

    2003-01-01

    This study supplemented by three charts and a list of biographies, is, for the first time, encompassing their life-data, their resumés and even their professional careers as well as political commitments shown by more than 200 Silesian students. They, at the University of Breslau, but also at other German universities, had joined the student fraternities in the 20-ies and early 30-ies of the 19th century and, in consequence, were persecuted by state authorities, notably in Prussia and, in the majority of cases, had been sentenced to prison terms of varying degrees. The first demagogic persecution, which happened in the first half of the twenties, culminating in 1822 in the Breslau Arminen Trail and ending up with the staging of the Youth-Association-Trail in 1826, had implicated about 100 Silesians, with a smaller portion of them - apart from teh three Youth-Association Silesians who were sentenced to five years imprisonment in a fortress - getting away with a relatively short "political fortress imprisonment". Later a considerable part of them made a career in the prussian judicial authority, in the institutions of higher learning, as parish priests, physicians and scientists, whereas any political engagement remained a rare exception. Out of the 137 Silesian members of the student fraternities affected by the second wave of persecution, the overwhelming majority of them being Protestants and originating partly from the middle classes, mostly artisans, and from intellectual background, with about a hundred of them being given essentially higher sentences ranging from six years up to capital punishment and, in the event of reprieves, they had to serve their sentences between six months and four-to-six years in a fortress. The majority of them made a medium-level professional career, never exceeding the medium ranks, as judicial officers, lawyers in state or communal services, parish priests, teachers or physicians. However, from this group of persecuted persons, a

  18. [Hypotheses and causes of body height progressions since mid 19th century--a scientific historical review. I: Discussion of causes since the end of the 19th century to mid 20th century, including references on body height development in the 19th century].

    PubMed

    Wurm, H

    1985-01-01

    This examination is trying to give a scientific historical survey of the hypothesis and the reasons for progression of height since the middle of the 19th century. These progressions of height are not based on a single reason, but were kept going by the addition of consecutive reasons. Physical relief is mainly responsible for the most recent phase of progression of height.

  19. Solar Source and CME Properties of Solar Cycle 23 Ground Level Enhancement Events

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat; Xie, H.; Yashiro, S.; Akiyama, S.; Makela, P.; Usoskin, I.

    2010-01-01

    Solar cycle 23 witnessed the most complete set of observations of coronal mass ejections (CMEs) associated with the Ground Level Enhancement (GLE) events. GLE events are extreme cases of solar energetic particle (SEP) events in that the energetic particles penetrate Earth's neutral atmosphere to be detected by neutron monitors. In this paper we present the CME and their source properties that seem to be equally extreme. These observations are consistent with the idea that the GLE particles are accelerated in the same way as the regular SEP events by CME-driven shocks. While we cannot rule out the possibility of the presence of a flare component during GLE events, we can definitely say that a shock component is present in all the GLE events. We provide additional information on the GLE-associated type II radio bursts, complex type III radio bursts, and soft X-ray flares, which are not very different from those associated with large SEP events. Finally we compare the properties of GLEassociated CMEs in cycle 23 with those in cycle 22.

  20. Evidence of scale height variations in the Martian ionosphere over the solar cycle

    NASA Astrophysics Data System (ADS)

    Sánchez-Cano, B.; Lester, M.; Witasse, O.; Milan, S. E.; Hall, B. E. S.; Blelly, P.-L.; Radicella, S. M.; Morgan, D. D.

    2015-12-01

    Solar cycle variations in solar radiation create density changes in any planetary ionosphere, which are well established in the Earth's case. At Mars, however, the ionospheric response to such changes is not well understood. We show the solar cycle impact on the topside ionosphere of Mars, using data from the Mars Advance Radar for Subsurface and Ionospheric Sounding (MARSIS) on board Mars Express. Topside ionospheric variability during the solar cycle is analyzed through neutral scale height behavior. For moderate and high solar activity phases, the topside electron density profile is reproduced with an altitude-variable scale height. However, for the period of extremely low solar activity in 2008 and 2009, the topside was smaller in density than in the other phases of the solar cycle, and there is evidence that it could be reproduced with either a constant scale height or a height-variable scale height with lower electron density. Moreover, the ionosphere during this time did not show any apparent dependence on the EUV flux. This singular behavior during low solar activity may respond to the presence of an induced magnetic field which can penetrate to lower ionospheric altitudes than in other phases of the solar cycle due to the reduced thermal pressure. Numerical simulations of possible scenarios for two different solar cycle phases indicate that this hypothesis is consistent with the observations.

  1. Coronal electron temperature in the protracted solar minimum, the cycle 24 mini maximum, and over centuries

    NASA Astrophysics Data System (ADS)

    Schwadron, N. A.; Goelzer, M. L.; Smith, C. W.; Kasper, J. C.; Korreck, K.; Leamon, R. J.; Lepri, S. T.; Maruca, B. A.; McComas, D.; Steven, M. L.

    2014-03-01

    Recent in situ observations of the solar wind show that charge states (e.g., the O7+/O6+and C6+/C5+abundance ratios) evolved through the extended, deep solar minimum between solar cycles 23 and 24 (i.e., from 2006 to 2009) reflecting cooler electron temperatures in the corona. We extend previous analyses to study the evolution of the coronal electron temperature through the protracted solar minimum and observe not only the reduction in coronal temperature in the cycles 23-24 solar minimum but also a small increase in coronal temperature associated with increasing activity during the "mini maximum" in cycle 24. We use a new model of the interplanetary magnetic flux since 1749 to estimate coronal electron temperatures over more than two centuries. The reduction in coronal electron temperature in the cycles 23-24 protracted solar minimum is similar to reductions observed at the beginning of the Dalton Minimum (˜1805-1840). If these trends continue to reflect the evolution of the Dalton Minimum, we will observe further reductions in coronal temperature in the cycles 24-25 solar minimum. Preliminary indications in 2013 do suggest a further post cycle 23 decline in solar activity. Thus, we extend our understanding of coronal electron temperature using the solar wind scaling law and compare recent reductions in coronal electron temperature in the protracted solar minimum to conditions that prevailed in the Dalton Minimum.

  2. The lost origin of chemical ecology in the late 19th century.

    PubMed

    Hartmann, Thomas

    2008-03-25

    The origin of plant chemical ecology generally dates to the late 1950s, when evolutionary entomologists recognized the essential role of plant secondary metabolites in plant-insect interactions and suggested that plant chemical diversity evolved under the selection pressure of herbivory. However, similar ideas had already flourished for a short period during the second half of the 19th century but were largely forgotten by the turn of the century. This article presents the observations and studies of three protagonists of chemical ecology: Anton Kerner von Marilaun (1831-1898, Innsbruck, Austria, and Vienna, Austria), who mainly studied the impact of geological, climatic, and biotic factors on plant distribution and survival; Léo Errera (1858-1906, Brussels, Belgium), a plant physiologist who analyzed the localization of alkaloids in plant cells and tissues histochemically; and Ernst Stahl (1848-1919, Jena, Germany), likely the first experimental ecologist and who performed feeding studies with snails and slugs that demonstrated the essential role of secondary metabolites in plant protection against herbivores. All three, particularly Stahl, suggested that these "chemical defensive means" evolved in response to the relentless selection pressure of the heterotrophic community that surrounds plants. Although convincingly supported by observations and experiments, these ideas were forgotten until recently. Now, more than 100 years later, molecular analysis of the genes that control secondary metabolite production underscores just how correct Kerner von Marilaun, Errera, and, particularly, Stahl were in their view. Why their ideas were lost is likely a result of the adamant rejection of all things "teleological" by the physiologists who dominated biological research at the time. PMID:18218780

  3. The lost origin of chemical ecology in the late 19th century

    PubMed Central

    Hartmann, Thomas

    2008-01-01

    The origin of plant chemical ecology generally dates to the late 1950s, when evolutionary entomologists recognized the essential role of plant secondary metabolites in plant–insect interactions and suggested that plant chemical diversity evolved under the selection pressure of herbivory. However, similar ideas had already flourished for a short period during the second half of the 19th century but were largely forgotten by the turn of the century. This article presents the observations and studies of three protagonists of chemical ecology: Anton Kerner von Marilaun (1831–1898, Innsbruck, Austria, and Vienna, Austria), who mainly studied the impact of geological, climatic, and biotic factors on plant distribution and survival; Léo Errera (1858–1906, Brussels, Belgium), a plant physiologist who analyzed the localization of alkaloids in plant cells and tissues histochemically; and Ernst Stahl (1848–1919, Jena, Germany), likely the first experimental ecologist and who performed feeding studies with snails and slugs that demonstrated the essential role of secondary metabolites in plant protection against herbivores. All three, particularly Stahl, suggested that these “chemical defensive means” evolved in response to the relentless selection pressure of the heterotrophic community that surrounds plants. Although convincingly supported by observations and experiments, these ideas were forgotten until recently. Now, more than 100 years later, molecular analysis of the genes that control secondary metabolite production underscores just how correct Kerner von Marilaun, Errera, and, particularly, Stahl were in their view. Why their ideas were lost is likely a result of the adamant rejection of all things “teleological” by the physiologists who dominated biological research at the time. PMID:18218780

  4. 19th century London dust-yards: A case study in closed-loop resource efficiency

    SciTech Connect

    Velis, Costas A.; Wilson, David C.; Cheeseman, Christopher R.

    2009-04-15

    The material recovery methods used by dust-yards in early 19th century London, England and the conditions that led to their development, success and decline are reported. The overall system developed in response to the market value of constituents of municipal waste, and particularly the high coal ash content of household 'dust'. The emergence of lucrative markets for 'soil' and 'breeze' products encouraged dust-contractors to recover effectively 100% of the residual wastes remaining after readily saleable items and materials had been removed by the thriving informal sector. Contracting dust collection to the private sector allowed parishes to keep the streets relatively clean, without the need to develop institutional capacity, and for a period this also generated useful income. The dust-yard system is, therefore, an early example of organised, municipal-wide solid waste management, and also of public-private sector participation. The dust-yard system had been working successfully for more than 50 years before the Public Health Acts of 1848 and 1875, and was thus important in facilitating a relatively smooth transition to an institutionalised, municipally-run solid waste management system in England. The dust-yards can be seen as early precursors of modern materials recycling facilities (MRFs) and mechanical-biological treatment (MBT) plants; however, it must be emphasised that dust-yards operated without any of the environmental and occupational health considerations that are indispensable today. In addition, there are analogies between dust-yards and informal sector recycling systems currently operating in many developing countries.

  5. Forgotten research from 19th century: science should not follow fashion.

    PubMed

    Galler, Stefan

    2015-02-01

    The fine structure of cross-striated muscle and its changes during contraction were known already in considerable detail in the 19th century. This knowledge was the result of studying birefringence properties of muscle fibres under the polarization microscope, a method mainly established by Brücke (Denk Kais Akad Wiss Math Naturwiss Cl 15:69-84, 1858) in Vienna, Austria. The knowledge was seemingly forgotten in the first half of the 20th century before it was rediscovered in 1954. This rediscovery was essential for the formulation of the sliding filament theory which represents the commonly accepted concept of muscle contraction (A.F. Huxley and Niedergerke, Nature 173:971-973, 1954; H.E. Huxley and Hanson, Nature 173:973-976, 1954). The loss of knowledge was the result of prevailing views within the scientific community which could be attributed to "fashion": it was thought that the changes of cross-striations, which were observed under the microscope, were inconsequential for contraction since other types of movements like cell crawling and smooth muscle contraction were not associated with similar changes of the fine structure. The basis for this assumption was the view that all types of movements associated with life must be caused by the same mechanisms. Furthermore, it was assumed that the light microscopy was of little use, because the individual molecules that carry out life functions cannot be seen under the light microscope. This unfortunate episode of science history teaches us that the progress of science can severely be retarded by fashion. PMID:25432331

  6. A study of density modulation index in the inner heliospheric solar wind during solar cycle 23

    SciTech Connect

    Bisoi, Susanta Kumar; Janardhan, P.; Ingale, M.; Subramanian, P.; Ananthakrishnan, S.; Tokumaru, M.; Fujiki, K. E-mail: jerry@prl.res.in E-mail: p.subramanian@iiserpune.ac.in E-mail: tokumaru@stelab.nagoya-u.ac.jp

    2014-11-01

    The ratio of the rms electron density fluctuations to the background density in the solar wind (density modulation index, ε {sub N} ≡ ΔN/N) is of vital importance for understanding several problems in heliospheric physics related to solar wind turbulence. In this paper, we have investigated the behavior of ε {sub N} in the inner heliosphere from 0.26 to 0.82 AU. The density fluctuations ΔN have been deduced using extensive ground-based observations of interplanetary scintillation at 327 MHz, which probe spatial scales of a few hundred kilometers. The background densities (N) have been derived using near-Earth observations from the Advanced Composition Explorer. Our analysis reveals that 0.001 ≲ ε {sub N} ≲ 0.02 and does not vary appreciably with heliocentric distance. We also find that ε {sub N} declines by 8% from 1998 to 2008. We discuss the impact of these findings on problems ranging from our understanding of Forbush decreases to the behavior of the solar wind dynamic pressure over the recent peculiar solar minimum at the end of cycle 23.

  7. Using dynamo theory to predict the sunspot number during solar cycle 21

    NASA Technical Reports Server (NTRS)

    Schatten, K. H.; Scherrer, P. H.; Svalgaard, L.; Wilcox, J. M.

    1978-01-01

    On physical grounds it is suggested that the polar field strength of the sun near a solar minimum is closely related to the solar activity of the following cycle. Four methods of estimating the polar magnetic field strength of the sun near solar minimum are employed to provide an estimate of the yearly mean sunspot number of cycle 21 at solar maximum of 140 + or - 20. This estimate may be considered a first-order attempt to predict the cycle activity using one parameter of physical importance based upon dynamo theory.

  8. The solar diameter is most probably constant over the solar cycle

    NASA Astrophysics Data System (ADS)

    Damé, Luc

    We analyzed 7 years of filtregrams data (150000 photograms and magnetograms) of the SOHO/MDI experiment. We used the maximum possible sampling compatible with full frame recording, carefully avoiding any suspicious filtregram. Going further than the previous analysis of Emilio et al. (Ap. J. 543, 2000) and Kuhn et al. (Ap. J. 613, 2004) we better corrected for changes in optical aberrations and, along Turmon et al. (Ap. J., 568, 396, 2002), we reduced radius measurement errors by identifying active regions from magnetograms and by avoiding radius measurements herein. We found that, within the limit of our noise level uncertainties (8 to 9 mas), the solar diameter is compatible with constancy over the half cycle investigated. Our results confirm the reanalysis of the 7 years of MDI data of Antia (Ap. J. 590, 2003), with a completely different method since using the ultra-precise frequency variation of the f-modes (fundamental modes linked to the diameter), who found (carefully removing the yearly Earth induced variations and avoiding the SOHO data gap of 1999) that the diameter is constant over the half solar cycle (radius variation are less than 0.6 km, 0.8 mas -nothing over noise level). We can conclude, along Antia, that: "If a careful analysis is performed, then it turns out that there is no evidence for any variation in the solar radius." There were no theoretical reasons for large solar radius variations and there is no observational evidence for them with consistent space observations made with 3 different approaches.

  9. The Influence of Solar Proton Events in Solar Cycle 23 on the Neutral Middle Atmosphere

    NASA Technical Reports Server (NTRS)

    Jackman, Charles H.; vonKonig, Miriam; Anderson, John; Roble, Raymond G.; McPeters, Richard D.; Fleming, Eric L.; Russell, James M.

    2004-01-01

    Solar proton events (SPEs) can cause changes in constituents in the Earth's middle atmosphere. The highly energetic protons cause ionizations, excitations, dissociations, and dissociative ionizations of the background constituents, which lead to the production of HO(x) (H, OH, HO2) and NO(y) (N, NO, NO2, NO3, N2O5, HNO3, HO2NO2, ClONO2, BrONO2). The HO(x) increases lead to short-lived ozone decreases in the mesosphere and upper stratosphere due to the short lifetimes of the HO, constituents. The NO(x) increases lead to long-lived stratospheric ozone changes because of the long lifetime of NO(y) constituents in this region. Solar cycle 23 was quite active with SPEs and very large fluxes of high energy protons occurred in July and November 2000, November 200 1, and April 2002. Smaller, but still substantial, proton fluxes impacted the Earth during other months in the 1997-2003 time period. The impact of the very large SPEs on the neutral middle atmosphere during solar cycle 23 will be discussed, including the HO(x), NO(y), ozone variations and induced atmospheric transport changes. Two multi-dimensional models, the Goddard Space Flight Center (GSFC) Two-dimensional (2D) Model and the Thermosphere Ionosphere Mesosphere Electrodynamic General Circulation Model (TIME-GCM), were used in computing the influence of the SPEs. The results of the GSFC 2D Model and the TIME-GCM will be shown along with comparisons to the Upper Atmosphere Research Satellite (UARS) Halogen Occultation Experiment (HALOE) and Solar Backscatter Ultraviolet 2 (SBUV/2) instruments.

  10. Rotation of solar magnetic fields for the current solar cycle 24

    SciTech Connect

    Shi, X. J.; Xie, J. L.

    2014-11-01

    The rotation of solar magnetic fields for the current solar cycle 24 is investigated through a cross-correlation analysis of the Carrington synoptic maps of solar photospheric magnetic fields during Carrington rotation numbers 2076-2146 (2008 October to 2014 January). The sidereal rotation rates of positive and negative magnetic fields at some latitudes are shown, and it can be found that the positive (negative) fields generally rotate faster than the negative (positive) fields in the southern (northern) hemisphere at low latitudes. The mean rotation profiles of total, positive, and negative magnetic fields between ±60° latitudes in the time interval are also obtained. It should be noted that both of the mean rotation profiles of the positive and negative magnetic fields, as well as the mean rotation profile of the total magnetic field, exhibit a quasi-rigid rotation at latitudes above about 55°. The mean rotation rates of the positive (negative) polarity reach their maximum values at about 9°(6)° latitude in the southern (northern) hemisphere. The mean rotation profile of the total magnetic field displays an obvious north-south asymmetry, where the rotation seems to be more differential in the northern hemisphere. The latitude variation in the rotation rate differences between positive and negative magnetic fields is further studied, and it is found that magnetic fields with the same polarity as the leading sunspots at a given hemisphere rotate faster than those with the opposite polarity, except for the zones around 52° latitude of the southern hemisphere and around 35° latitude of the northern hemisphere. The implication of these results is discussed. It is clear that the obtained results can provide some observational constraints on the theoretical research of the mechanisms of differential rotation and solar cycle.

  11. Predictions of the onset of mini ice age in the 25th solar cycle

    NASA Astrophysics Data System (ADS)

    Kumar, Rajiv

    2016-07-01

    Predictions of the ir-regularty in the 11 year heartbeat of the sun due to asyncronous of the two layered dynamo effect would result in mini ice age as in the Maunder minimum.The onset of this event is expected in the begining of 25th solar cycle and would go to its maximum in the 26th solar cycle.The minimum temperature is expected in 2028 due to the fall of solar activity by 60 % termed as solar hibernation.The predictions are based on the observations obtained by the Royal Greenwich observatory since 1874. Keywords: Dynamo effect,munder minimum,Solar hybernation

  12. Sunspot variation and selected associated phenomena: A look at solar cycle 21 and beyond

    NASA Technical Reports Server (NTRS)

    Wilson, R. M.

    1982-01-01

    Solar sunspot cycles 8 through 21 are reviewed. Mean time intervals are calculated for maximum to maximum, minimum to minimum, minimum to maximum, and maximum to minimum phases for cycles 8 through 20 and 8 through 21. Simple cosine functions with a period of 132 years are compared to, and found to be representative of, the variation of smoothed sunspot numbers at solar maximum and minimum. A comparison of cycles 20 and 21 is given, leading to a projection for activity levels during the Spacelab 2 era (tentatively, November 1984). A prediction is made for cycle 22. Major flares are observed to peak several months subsequent to the solar maximum during cycle 21 and to be at minimum level several months after the solar minimum. Additional remarks are given for flares, gradual rise and fall radio events and 2800 MHz radio emission. Certain solar activity parameters, especially as they relate to the near term Spacelab 2 time frame are estimated.

  13. The solar magnetic cycle and the presence of an inclined relic field in the sun

    NASA Astrophysics Data System (ADS)

    Bravo, S.; Stewart, G. A.

    The evolution of the solar magnetic field through its 22 year cycle shows a varying inclination of the magnetic equator at 2.5 Rs from about 0 deg during solar minimum up to 90 deg during solar maximum, as measured with respect to the solar equator. We show that this behavoir could be explained by the presence of a small dipole relic field which has a high inclination with respect to the solar rotation axis and points southward. This fossil field would lead to a larger polar field during the negative polarity phase of the cycle, in accordance with observations. It may also help to explain the asymmetry observed in the solar activity of the northern and southern hemispheres, the appearance of some particularly active longitudes on the Sun, as well as other asymmetrical characteristics of the solar activity cycles.

  14. THE THERMAL PROPERTIES OF SOLAR FLARES OVER THREE SOLAR CYCLES USING GOES X-RAY OBSERVATIONS

    SciTech Connect

    Ryan, Daniel F.; Gallagher, Peter T.; Milligan, Ryan O.; Dennis, Brian R.; Kim Tolbert, A.; Schwartz, Richard A.; Alex Young, C.

    2012-10-15

    Solar flare X-ray emission results from rapidly increasing temperatures and emission measures in flaring active region loops. To date, observations from the X-Ray Sensor (XRS) on board the Geostationary Operational Environmental Satellite (GOES) have been used to derive these properties, but have been limited by a number of factors, including the lack of a consistent background subtraction method capable of being automatically applied to large numbers of flares. In this paper, we describe an automated Temperature and Emission measure-Based Background Subtraction method (TEBBS), that builds on the methods of Bornmann. Our algorithm ensures that the derived temperature is always greater than the instrumental limit and the pre-flare background temperature, and that the temperature and emission measure are increasing during the flare rise phase. Additionally, TEBBS utilizes the improved estimates of GOES temperatures and emission measures from White et al. TEBBS was successfully applied to over 50,000 solar flares occurring over nearly three solar cycles (1980-2007), and used to create an extensive catalog of the solar flare thermal properties. We confirm that the peak emission measure and total radiative losses scale with background subtracted GOES X-ray flux as power laws, while the peak temperature scales logarithmically. As expected, the peak emission measure shows an increasing trend with peak temperature, although the total radiative losses do not. While these results are comparable to previous studies, we find that flares of a given GOES class have lower peak temperatures and higher peak emission measures than previously reported. The TEBBS database of flare thermal plasma properties is publicly available at http://www.SolarMonitor.org/TEBBS/.

  15. Solar Cycle Dependence of the Solar Wind Dynamics: Pioneer, Voyager, and Ulysses from 1 to 5 AU

    NASA Technical Reports Server (NTRS)

    Gonzalez-Esparza, J. A.; Smith, E. J.

    1996-01-01

    Significant differences between Pioneer and Voyager observations were found in solar wind structure between 1 to 6 AU. These disagreements were attributed to temporal effects related to the solar cycle, but no unifying study of Pioneer-Voyager observations was performed.

  16. Pioneer and Voyager observations of solar cycle variations in the outer heliosphere

    NASA Technical Reports Server (NTRS)

    Gazis, P. R.

    1994-01-01

    Solar wind measurements from the Pioneer 10, Pioneer 11, and Voyager 2 spacecraft are now available through mid-1993. These measurements extend our knowledge of the outer heliosphere to heliographic latitudes that range between -10 deg and 17.5 deg, and provide insight into the variation with solar cycle of the structure of the distant solar wind. The average temperature, mass flux density, dynamic pressure, and kinetic and thermal energy flux densities varied strongly with solar cycle at the latitude of Pioneer 11 (10 deg to 17 deg N), but were almost constant in the vicinity of the solar equator. These parameters may have increased with latitude between the solar equator and 17 deg N. There was also a short-term variation in average solar wind parameters near the time of the 1986 solar minimum, when the inclination of the heliospheric current sheet dropped below the latitude of Pioneer 11.

  17. The solar wind structure and heliospheric magnetic field in the solar Cycle 23-24 minimum and in the increasing phase of Cycle 24

    NASA Astrophysics Data System (ADS)

    Gibson, S. E.; Zhao, L.; Fisk, L. A.

    2011-12-01

    The solar wind structure and the heliospheric magnetic field were substantially different in the latest solar minimum between solar Cycle 23 and 24 from the previous minimum. Compared with the previous minimum, in the latest solar minimum, the heliospheric magnetic field strength was substantially reduced; the streamer-associated-low-temperature solar wind (streamer-stalk wind) was distributed in a narrower region relative to the heliospheric current sheet (HCS); the slow-proton-speed solar wind was scattered in a wider latitudinal region; and there are more large and steady coronal holes at low latitude. We offer an explanation for the decreased magnetic-field strength and the narrowed streamer-stalk wind based on an analysis of the Ulysses and ACE in-situ observations. Solar-wind composition data are used to demonstrate that there are two distinct structures of solar wind: solar wind likely to originate from the stalk of the streamer belt (the highly elongated loops that underlie the HCS), and solar wind from outside this region. The region outside the streamer-stalk region is noticeably larger in the Cycle 23-24 minimum; however, the increased area can account for the reduction in the heliospheric magnetic-field strength in that minimum. Thus, the total magnetic flux contained in this region is the same in the two minima. To have a further understanding of the solar wind structure and its solar source, we ballistically map the ACE in-situ observation back along a radial trajectory from 1 AU to the solar source surface (r = 2.5Rsun) using the observed proton speeds. Then we track the field line from the source surface to the solar surface using a potential-field-source-surface (PFSS) extrapolation model. So the ACE observations, including the heliospheric magnetic field, the solar wind compositional and dynamic properties at 1AU, can be connected to their coronal sources on the solar surface. Synoptic maps showing this connection will be provided, and based on

  18. Helioseismic inferences of the solar cycles 23 and 24: GOLF and VIRGO observations

    NASA Astrophysics Data System (ADS)

    Salabert, D.; García, R. A.; Jiménez, A.

    2014-12-01

    The Sun-as-a star helioseismic spectrophotometer GOLF and photometer VIRGO instruments onboard the SoHO spacecraft are collecting high-quality, continuous data since April 1996. We analyze here these unique datasets in order to investigate the peculiar and weak on-going solar cycle 24. As this cycle 24 is reaching its maximum, we compare its rising phase with the rising phase of the previous solar cycle 23.

  19. Segmentation of EUV spectroheliograms to track and measure solar EUVI variability within a solar cycle

    NASA Astrophysics Data System (ADS)

    Martinez-Galarce, D. S.; Slater, G. L.; Mcintosh, S. W.

    2011-12-01

    of ~1.3 solar cycles (~16 years). Using this segmented imaging approach the goal of the study is to determine solar EUVI variability observed in each EIT bandpass, as a function of areal identification (e.g., active vs. coronal hole EUV variability), over the entire period of observations.

  20. Probing the equinoctial hypothesis over recent solar cycles

    NASA Astrophysics Data System (ADS)

    Farrugia, C.; Miyoshi, Y.; Jordanova, V.

    2003-04-01

    According to Russell and McPherron (1973), stronger and more frequent storms are induced on a half-annual cadence due to the tilt of the Earth's dipole. We carry out a statistical investigation of this using 1-hour averaged Dst index values as a measure of the strength of geomagnetic storms over the period 1969-2001 (3 solar cycles), and energetic electron and proton fluxes measured BY NOAA/TIROS typical of the inner ring current and radiation belts, respectively for the last 2 cycles in the interval 1979-2001. We subdivide the data sets into ascending (sunpsot number > 50) and descending phases (< 50 ), and the storm strengths into two categories: peak hourly Dst < -60 nT, and hourly peak Dst < -100 nT. The variation equinox / solstice is evident in both Dst measurments and energetic particles fluxes. The number of storms falls off exponentially with storm strength both at equinox and solstice. There is practically no difference in the average storm strength at equinox/solstice. However, the storm frequency of both categories is larger at equinox. Exceptional cases like the Bastille day (July 2000) form a large-scale deviation from this pattern. The aim of this study is to understand the effects of the orientation of the Earth's dipole on geomagnetic strom dynamics and to reveal systematics which will be useful for the development of space weather predictions. C. T. Russell and R. L. MCPherron, JGR, 78, 92, 1973 Work supported in part by NASA GRANT NAG 5-10883.

  1. Astrometry and early astrophysics at Kuffner Observatory in the late 19th century

    NASA Astrophysics Data System (ADS)

    Habison, Peter

    The astronomer and mathematician Norbert Herz encouraged Moriz von Kuffner, owner of the beer brewery in Ottakring, to finance a private scientific observatory in the western parts of Vienna. In the years 1884-87 the Kuffner Observatory was built at the Gallitzinberg in Wien-Ottakring. It was an example of enlighted patronage and noted at the time for its rapid acquisition of new instruments and by increasing international recognition. It contained the largest heliometer in the world and the largest meridian circle in the Austrian-Hungarian Empire. Of the many scientists who worked here we mention Leo de Ball, Gustav Eberhard, Johannes Hartmann and we should not forget Karl Schwarzschild. Here in Vienna he published papers on celestial mechanics, measuring techniques, optics and his fundamental papers concerning photographic photometry, in particular the quantitative determination of the departure of the reciprocity law. The telescope and the associated camera with which he carried out his measurements are still in existence at the observatory. The observatory houses important astronomical instruments from the 19th century. All telescopes were made by Repsold und Söhne in Hamburg, and Steinheil in Munich. These two German companies were best renowned for quality and precision in high standard astronomical instruments. The Great Refractor (270/3500 mm) is still the third largest refractor in Austria. It was installed at the observatory in 1886 and was used together with the Schwarzschild Refractor for early astrophysical work including photography. It is this double refractor, where Schwarzschild carried out his measurements on photographic photometry. The Meridian Circle (132/1500 mm) was the largest meridian passage instrument of the Austro-Hungarian Empire. Today it is the largest meridian circle in Austria and still one of the largest in Europe. The telescope is equipped with one of the first impersonal micrometers of that time. First observations were carried

  2. Instrumental evidence of an unusually strong West African Monsoon in the 19th century

    NASA Astrophysics Data System (ADS)

    Gallego, David; Ordoñez, Paulina; Ribera, Pedro; Peña-Ortiz, Cristina; Garcia-Herrera, Ricardo; Vega, Inmaculada; Gomez, Francisco de Paula

    2016-04-01

    The precipitation in the Sahel -which is mainly controlled by the dynamics of the West African Monsoon-, has been in the spot of the climate community for the last three decades due to the persistence of the drought period that started in the 1970s. Unfortunately, reliable meteorological series in this area are only available since the beginning of the 20th Century, thus limiting our understanding of the significance of this period from a long term perspective. Currently, our knowledge of what happened in times previous to the 20th Century essentially relies in documentary or proxy sources. In this work, we present the first instrumental evidence of a 50 year-long period characterised by an unusually strong West African monsoon in the19th Century. Following the recent advances in the generation of climatic indices based on data from ship's logbooks, we used historical wind observations to compute a new index (the so-called ASWI) for characterising the strength of the West African Monsoon. The ASWI is based in the persistence of the southwesterly winds in the [29°W-17°W;7°N-13°N] area and it has been possible to compute it since 1790 for July and since 1839 for August and September. We show that the ASWI is a reliable measure of the monsoon's strength and the Sahelian rainfall. Our new series clearly shows the well-known drought period starting in the 1970s. During this dry period, the West African Monsoon was particularly weak and interestingly, we found that since then, the correlations with different climatic patterns such as the Pacific and Atlantic "El Niño" changed significantly in relation to those of the previous century. Remarkably, our results also show that the period 1839-1890 was characterised by an unusually strong and persistent monsoon. Notwithstanding, two of the few dry years within this period were concurrent with large volcanic eruptions in the Northern Hemisphere. This latter result supports the recently suggested relationship between major

  3. Theoretical astrophysics in the 19th century (Homage to Radó von Kövesligethy)

    NASA Astrophysics Data System (ADS)

    Balázs, Lajos G.

    The nature of astronomical information is determined mostly by the incoming light. Theoretical astrophysics means basically the theory of light emission and its relation to the physical constitution of the emitting celestial bodies. The necessary physical disciplines include theory of gravitation, theory of radiation, thermodynamics, matter--radiation interaction. The most significant theoretical achievement in the 17th - 18th century was the axiomatic foundation of mechanics and the law of gravitation. In the context of the nature of light, there were two conceptions: Newton contra Huygens, i.e. particle versus wave phenomenon. Using the theory of gravitation, first speculations appeared on black holes (Michell, Laplace), cosmogony (Kant-Laplace theory), the structure of the Milky Way (Kant), and the explanation of motion of the celestial bodies. The Olbers Paradox, formulated in the 19th century, is still one of the most significant constraints on observational cosmology. The development of thermodynamics, matter-radiation interaction, development of the theory of electromagnetism became important milestones. Maxwell's theory was the classical framework of the interaction between matter and radiation. Kirchhoff and Bunsen's revolutionary discovery of spectral analysis (1859) showed that observation of spectra makes it possible to study the chemical composition of emitting bodies. Thermodynamics predicted the existence of the black body radiation. It did not succeed, however, to determine the functional form of the wavelength dependence. A combination of the thermodynamic equation of state with the equation of hydrostatics resulted in the first stellar models (Lane, Ritter, Schuster). The first successful spectral equation of black body radiation was the theory of continuous spectra of celestial bodies by Radó von Kövesligethy (published 1885 in Hungarian, 1890 in German). Kövesligethy made several assumptions on the matter-radiation interaction: radiating

  4. SOLAR CYCLE PROPAGATION, MEMORY, AND PREDICTION: INSIGHTS FROM A CENTURY OF MAGNETIC PROXIES

    SciTech Connect

    Munoz-Jaramillo, Andres; DeLuca, Edward E.; Dasi-Espuig, Maria; Balmaceda, Laura A. E-mail: edeluca@cfa.harvard.edu E-mail: lbalmaceda@icate-conicet.gob.ar

    2013-04-20

    The solar cycle and its associated magnetic activity are the main drivers behind changes in the interplanetary environment and Earth's upper atmosphere (commonly referred to as space weather). These changes have a direct impact on the lifetime of space-based assets and can create hazards to astronauts in space. In recent years there has been an effort to develop accurate solar cycle predictions (with aims at predicting the long-term evolution of space weather), leading to nearly a hundred widely spread predictions for the amplitude of solar cycle 24. A major contributor to the disagreement is the lack of direct long-term databases covering different components of the solar magnetic field (toroidal versus poloidal). Here, we use sunspot area and polar faculae measurements spanning a full century (as our toroidal and poloidal field proxies) to study solar cycle propagation, memory, and prediction. Our results substantiate predictions based on the polar magnetic fields, whereas we find sunspot area to be uncorrelated with cycle amplitude unless multiplied by area-weighted average tilt. This suggests that the joint assimilation of tilt and sunspot area is a better choice (with aims to cycle prediction) than sunspot area alone, and adds to the evidence in favor of active region emergence and decay as the main mechanism of poloidal field generation (i.e., the Babcock-Leighton mechanism). Finally, by looking at the correlation between our poloidal and toroidal proxies across multiple cycles, we find solar cycle memory to be limited to only one cycle.

  5. [The construction of a medical discipline and its challenges: Orthopedics in Switzerland during the 19th and 20th centuries].

    PubMed

    Kaba, Mariama

    2015-07-01

    During the 19th century, numerous figures, with different qualifications, claimed to practice orthopedics: doctors, surgeons, inventors of equipment and instruments, and other empiricists. They performed certain types of techniques, massages, surgical operationsand/or fitted prostheses. The polysemous notion of orthopedics had created conflicts of interest that would reach their height at the end of the 19th century. The integration of orthopedics into the training at the university level enhanced its proximity to surgery, a discipline that has dominated the so-called modern medicine. During the 20th century, various medical branches defend the legitimacy of certain orthopedic practices, thereby threating to a degree the title itself of this specialization. By examining the challenges that have shaped the history of orthopedics in Switzerland, this article also seeks to shed light on the strategies that were implemented in adopting a medical and technical discipline within a transforming society.

  6. The Lowland Rivers of The Netherlands - Geodiversity and Cultural Heritage on 19th and early 20th century Landscape Paintings

    NASA Astrophysics Data System (ADS)

    Jungerius, Pieter Dirk; van den Ancker, Hanneke; Moes, Constance

    2015-04-01

    One of the major Dutch landscapes is formed by lowland rivers. They divide the country in a southern and a northern part, both physically and culturally. We screened the freely available database of 19th and early 20th century paintings of Simonis & Buunk, www.simonis-buunk.com, looking for lowland river landscapes depicting geodiversity and cultural heritage relationships (See References for other landscapes). Emperor Napoleon declared The Netherlands as naturally belonging to his empire as its lands originated from muds originating in France and transported there by the big rivers. A description that may have given rise to the idea of the Netherlands as a delta, but from a geomorphological perspective The Netherlands consists of series of river plains of terrestrial origin, of which the north-western part are subsiding and invaded by the sea. Now, the rivers Meuse and Rhine (including its branches Waal and IJssel) meander through ever larger river plains before reaching the North Sea. They end in estuaries, something one would not expect of rivers with catchments discharging a large part of Western Europe. Apart from the geological subsidence, the estuaries might be due to human interference, the exploitation of peat and building of dikes since the 11th century, heavy storms and the strong tidal currents. Archaeological finds show Vikings and Romans already used the river Rhine system for trading and transporting goods. During the Roman Empire the Rhine was part of The Limes, the northern defence line of the empire. Romans already influenced the distribution of water over the different river branches. Since the middle of the 19th century groins and canalization drastically changed the character of the rivers. The 19th and early 20th century landscape paintings illustrate this change as well as changes in land use. Examples of geodiversity and cultural heritage relationships shown: - meanders and irregular banks disappear as river management increases, i.a. bends

  7. Concept definition study of small Brayton cycle engines for dispersed solar electric power systems

    NASA Technical Reports Server (NTRS)

    Six, L. D.; Ashe, T. L.; Dobler, F. X.; Elkins, R. T.

    1980-01-01

    Three first-generation Brayton cycle engine types were studied for solar application: a near-term open cycle (configuration A), a near-term closed cycle (configuration B), and a longer-term open cycle (configuration C). A parametric performance analysis was carried out to select engine designs for the three configurations. The interface requirements for the Brayton cycle engine/generator and solar receivers were determined. A technology assessment was then carried out to define production costs, durability, and growth potential for the selected engine types.

  8. GLE and the NON-GLE Solar Events Observed by AMS-02 in Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Bindi, V.; Consolandi, C.; Corti, C.; Whitman, K.

    2014-12-01

    The Alpha Magnetic Spectrometer (AMS-02) is a high energy particle detector installed on the International Space Station (ISS) on May 2011 to study origin and nature of cosmic rays in the energy range from hundreds of MeV to a few TeV. In the first 3 years of operation, AMS-02 measured the highest part of the Solar Energetic Particle (SEP) spectra produced during M-and X-class flares and fast Coronal Mass Ejection. AMS-02 is able to perform precise measurements in a short period of time which is typical of these transient phenomena and to collected enough statistics to fully measure fine structures and time evolution of the spectrum. So far in Solar Cycle 24, one official Ground Level Enhancement (GLE) was observed on May 17, 2012 by Neutron Monitors (NM) while another possible GLE on January 6, 2014 was detected by South Pole NM. Observations by GOES-13, in the high energy proton channels, suggest that there were only 5 SEP events with energies above 500 MeV in this Cycle 24. AMS-02 observations, instead, indicate that since May 2011 there were more than 5 solar events with energies above 500 MeV at Earth. AMS-02 observations, with unprecedented resolution, large acceptance and high statistics, can therefore help the heliophysics community to better understand the true behavior of SEPs at high energies and to constrain models of SEP production. The SEP fluxes of GLE and NON-GLE events observed by AMS-02 will be presented.

  9. Solar-cycle variation of the rotational shear near the solar surface

    NASA Astrophysics Data System (ADS)

    Barekat, A.; Schou, J.; Gizon, L.

    2016-10-01

    Context. Helioseismology has revealed that the angular velocity of the Sun increases with depth in the outermost 35 Mm of the Sun. Recently, we have shown that the logarithmic radial gradient (dlnΩ/dlnr) in the upper 10 Mm is close to -1 from the equator to 60° latitude. Aims: We aim to measure the temporal variation of the rotational shear over solar cycle 23 and the rising phase of cycle 24 (1996-2015). Methods: We used f mode frequency splitting data spanning 1996 to 2011 from the Michelson Doppler Imager (MDI) and 2010 to 2015 from the Helioseismic Magnetic Imager (HMI). In a first for such studies, the f mode frequency splitting data were obtained from 360-day time series. We used the same method as in our previous work for measuring dlnΩ/dlnr from the equator to 80° latitude in the outer 13 Mm of the Sun. Then, we calculated the variation of the gradient at annual cadence relative to the average over 1996 to 2015. Results: We found the rotational shear at low latitudes (0° to 30°) to vary in-phase with the solar activity, varying by ~± 10% over the period 1996 to 2015. At high latitudes (60° to 80°), we found rotational shear to vary in anti-phase with the solar activity. By comparing the radial gradient obtained from the splittings of the 360-day and the corresponding 72-day time series of HMI and MDI data, we suggest that the splittings obtained from the 72-day HMI time series suffer from systematic errors. Conclusions: We provide a quantitative measurement of the temporal variation of the outer part of the near surface shear layer which may provide useful constraints on dynamo models and differential rotation theory.

  10. [Looking at several fleeting hygiene journals from the 19th Century kept at the National Library of France].

    PubMed

    Anne, Boyer; Cantau, Alina

    2010-01-01

    The authors investigate some ephemeral reviews of private and public hygiene of the 19th century in the Bibliothèque nationale de France (BnF). They examine the general context of their publication, describe them according to the usual bibliographic criteria, analyse their aims and content, and try to understand why they were so ephemeral. These reviews are in a very poor state and computerisation, they hope, might give them a new life.

  11. Stature in 19th and early 20th century Copenhagen. A comparative study based on skeletal remains.

    PubMed

    Jørkov, Marie Louise S

    2015-12-01

    Individual stature depends on multifactorial causes and is often used as a proxy for investigating the biological standard of living. While the majority of European studies on 19th and 20th century populations are based on conscript heights, stature derived from skeletal remains are scarce. For the first time in Denmark this study makes a comparison between skeletal stature and contemporary Danish conscript heights and investigates stature of males and females temporally and between socially distinct individuals and populations in 19th and early 20th century Copenhagen. A total of 357 individuals (181 males, 176 females) excavated at the Assistens cemetery in Copenhagen is analyzed. Two stature regression formulae (Trotter, 1970; Boldsen, 1990) are applied using femur measurements and evaluated compared to conscript heights. The results indicate that mean male stature using Boldsen follows a similar trend as the Danish conscript heights and that Trotter overestimate stature by ca. 6cm over Boldsen. At an inter population level statistically significant differences in male stature are observed between first and second half of the 19th century towards a slight stature decrease and larger variation while there are no significant changes observed in female stature. There are insignificant differences in stature between middle and high class individuals, but male stature differs statistically between cemeteries (p=0.000) representing middle/high class, paupers and navy employees, respectively. Female stature had no significant wealth gradient (p=0.516). This study provides new evidence of stature among males and females during the 19th century and suggests that males may have been more sensitive to changes in environmental living and nutrition than females.

  12. Stature in 19th and early 20th century Copenhagen. A comparative study based on skeletal remains.

    PubMed

    Jørkov, Marie Louise S

    2015-12-01

    Individual stature depends on multifactorial causes and is often used as a proxy for investigating the biological standard of living. While the majority of European studies on 19th and 20th century populations are based on conscript heights, stature derived from skeletal remains are scarce. For the first time in Denmark this study makes a comparison between skeletal stature and contemporary Danish conscript heights and investigates stature of males and females temporally and between socially distinct individuals and populations in 19th and early 20th century Copenhagen. A total of 357 individuals (181 males, 176 females) excavated at the Assistens cemetery in Copenhagen is analyzed. Two stature regression formulae (Trotter, 1970; Boldsen, 1990) are applied using femur measurements and evaluated compared to conscript heights. The results indicate that mean male stature using Boldsen follows a similar trend as the Danish conscript heights and that Trotter overestimate stature by ca. 6cm over Boldsen. At an inter population level statistically significant differences in male stature are observed between first and second half of the 19th century towards a slight stature decrease and larger variation while there are no significant changes observed in female stature. There are insignificant differences in stature between middle and high class individuals, but male stature differs statistically between cemeteries (p=0.000) representing middle/high class, paupers and navy employees, respectively. Female stature had no significant wealth gradient (p=0.516). This study provides new evidence of stature among males and females during the 19th century and suggests that males may have been more sensitive to changes in environmental living and nutrition than females. PMID:26256129

  13. SOLAR CYCLE 24: CURIOUS CHANGES IN THE RELATIVE NUMBERS OF SUNSPOT GROUP TYPES

    SciTech Connect

    Kilcik, A.; Yurchyshyn, V. B.; Ozguc, A.; Rozelot, J. P.

    2014-10-10

    Here, we analyze different sunspot group (SG) behaviors from the points of view of both the sunspot counts (SSCs) and the number of SGs, in four categories, for the time period of 1982 January-2014 May. These categories include data from simple (A and B), medium (C), large (D, E, and F), and decaying (H) SGs. We investigate temporal variations of all data sets used in this study and find the following results. (1) There is a very significant decrease in the large groups' SSCs and the number of SGs in solar cycle 24 (cycle 24) compared to cycles 21-23. (2) There is no strong variation in the decaying groups' data sets for the entire investigated time interval. (3) Medium group data show a gradual decrease for the last three cycles. (4) A significant decrease occurred in the small groups during solar cycle 23, while no strong changes show in the current cycle (cycle 24) compared to the previous ones. We confirm that the temporal behavior of all categories is quite different from cycle to cycle and it is especially flagrant in solar cycle 24. Thus, we argue that the reduced absolute number of the large SGs is largely, if not solely, responsible for the weak cycle 24. These results might be important for long-term space weather predictions to understand the rate of formation of different groups of sunspots during a solar cycle and the possible consequences for the long-term geomagnetic activity.

  14. The Impact Of Torsional Oscillations On The Solar Cycle: The Waldmeier-effect As An Outcome

    NASA Astrophysics Data System (ADS)

    Mahajan, Sushant S.; Nandy, Dibyendu; Dwivedi, Bhola N.; Antia, H. M.

    2016-05-01

    Temporal variations in the Sun’s internal velocity field with a periodicity of about 11 years have been observed in the last three decades. The period of these torsional oscillations and their latitudinal propagation roughly coincide with the period and equatorward propagation of sunspots which originate from a magnetohydrodynamic dynamo mechanism operating in the Sun’s interior. While the solar differential rotation plays an important role in this dynamo mechanism by inducting the toroidal component of magnetic field, the impact of torsional oscillations on the dynamo mechanism - and hence the solar cycle - is not well understood. Here, we include the observed torsional oscillations into a flux transport dynamo model of the solar cycle to inves- tigate their effect. Although the overall amplitude of the solar cycle does not change significantly on inclusion of torsional oscillations we find that all the characteristics of the Waldmeier effect inthe sunspot cycle are qualitatively reproduced by varying only the amplitude of torsional oscillations. The Waldmeier effect, first noted in 1935, includes the important characteristic that the amplitude of sunspot cycles is anti-correlated to their rise time; cycles with high initial rise rate tend to be stronger. This has implications for solar cycle predictions. Our result suggests that the Waldmeier effect is a plausible outcome of cycle-to-cycle modulation of torsional oscillations and provides a physical basis for sunspot cycle forecasts based on torsional oscillation observations.

  15. Pictures, preparations, and living processes: the production of immediate visual perception (anschauung) in the late-19th-century physiology.

    PubMed

    Schmidgen, Henning

    2004-01-01

    This paper addresses the visual culture of the late-19th-century experimental physiology. Taking this case of Johann Nopomuk Czermak (1828-1873) as a key example, it argues that images played a crucial role in acquiring experimental physiological skills. Czermak, Emil Du Bois-Reymond (1818-1896) and other late-19th-century physiologists sought to present the achievements and perspective of their discipline by way of "immediate visual perception (unmittelbare Anschauung)." However, the images they produced and presented for this purpose were strongly mediated. By means of specifically designed instruments, such as the "cardioscope," the "contraction telegraph," and the "frog pistol," and specifically constructed rooms, so-called "spectatoriums," physiologists trained and controlled experiments on their own. Studying the material culture of physiological image production reveals that technological resources such as telegraphy, photography, and even railways contributed to making physiological facts anschaulich. At the same time, it shows that the more traditional image techniques of anatomy played an important role in physiological lecture halls, especially when it came to displaying the details of vivisection experiments to the public. Thus, the images of late 19th century physiology stood half-way between machines and organisms, between books and instruments.

  16. [The comparison of the two Ottoman books of anatomy (17-19th centuries) with regard to the circulatory system].

    PubMed

    Uluçam, E; Gökçe, N

    2000-01-01

    17th and 19th centuries were particularly important for the development of the Ottoman medicine. Westernization which had already started in the 17th century continued along the 19th and the early 20th centuries. Turkish physicians began to contact with their European colleagues and in this period Latin medical terminology began to appear in the Ottoman medical literature. Sirvanli Semseddin Itaki's work of the 17th century, the Teşrihü'l Ebdan ve Tercüman-i Kibale-i Feylesufan, is the first illustrated Turkish manuscript of anatomy. The illustrations are qualified as developed examples, compared with the medical literature and knowledge of the period. In the 19th century, Sanizade Mehmet Ataullah Efendi (1771-1826) wrote a modern book of anatomy for the Ottoman medical doctors. Miyarü'l Etibba was one of the earliest printed medical books in Turkish. The second volume of Sanizade's Hamse, Miratü'l Ebdan fi Teşrih-i Azai'l Insan is the first printed Ottoman book on anatomy. In Usulü't-Tabia, the third volume of Hamse, the circulatory system is discussed. In this article, we studied the circulatory system described in Semseddin Itaki's Teşrih-ül Ebdan ve Tercüman-i Kibale-i Feylesufan and in Sanizade's Usulü't-Tabia and compared them.

  17. Pictures, preparations, and living processes: the production of immediate visual perception (anschauung) in the late-19th-century physiology.

    PubMed

    Schmidgen, Henning

    2004-01-01

    This paper addresses the visual culture of the late-19th-century experimental physiology. Taking this case of Johann Nopomuk Czermak (1828-1873) as a key example, it argues that images played a crucial role in acquiring experimental physiological skills. Czermak, Emil Du Bois-Reymond (1818-1896) and other late-19th-century physiologists sought to present the achievements and perspective of their discipline by way of "immediate visual perception (unmittelbare Anschauung)." However, the images they produced and presented for this purpose were strongly mediated. By means of specifically designed instruments, such as the "cardioscope," the "contraction telegraph," and the "frog pistol," and specifically constructed rooms, so-called "spectatoriums," physiologists trained and controlled experiments on their own. Studying the material culture of physiological image production reveals that technological resources such as telegraphy, photography, and even railways contributed to making physiological facts anschaulich. At the same time, it shows that the more traditional image techniques of anatomy played an important role in physiological lecture halls, especially when it came to displaying the details of vivisection experiments to the public. Thus, the images of late 19th century physiology stood half-way between machines and organisms, between books and instruments. PMID:15685744

  18. Temporal Offsets Between Maximum CME Speed Index and Solar, Geomagnetic, and Interplanetary Indicators During Solar Cycle 23 and the Ascending Phase of Cycle 24

    NASA Astrophysics Data System (ADS)

    Özgüç, A.; Kilcik, A.; Georgieva, K.; Kirov, B.

    2016-05-01

    On the basis of a morphological analysis of yearly values of the maximum coronal mass ejection (CME) speed index, the sunspot number and total sunspot area, sunspot magnetic field, and solar flare index, the solar wind speed and interplanetary magnetic field strength, and the geomagnetic Ap and D_{st} indices, we point out the particularities of solar and geomagnetic activity during the last Cycle 23, the long minimum that followed it, and the ascending branch of Cycle 24. We also analyze the temporal offset between the maximum CME speed index and the above-mentioned solar, geomagnetic, and interplanetary indices. It is found that this solar activity index, analyzed jointly with other solar activity, interplanetary parameters, and geomagnetic activity indices, shows a hysteresis phenomenon. It is observed that these parameters follow different paths for the ascending and descending phases of Cycle 23. The hysteresis phenomenon represents a clue in the search for physical processes responsible for linking the solar activity to near-Earth and geomagnetic responses.

  19. Supercritical CO2 Power Cycles: Design Considerations for Concentrating Solar Power

    SciTech Connect

    Neises, Ty; Turchi, Craig

    2014-09-01

    A comparison of three supercritical CO2 Brayton cycles: the simple cycle, recompression cycle and partial-cooling cycle indicates the partial-cooling cycle is favored for use in concentrating solar power (CSP) systems. Although it displays slightly lower cycle efficiency versus the recompression cycle, the partial-cooling cycle is estimated to have lower total recuperator size, as well as a lower maximum s-CO2 temperature in the high-temperature recuperator. Both of these effects reduce recuperator cost. Furthermore, the partial-cooling cycle provides a larger temperature differential across the turbine, which translates into a smaller, more cost-effective thermal energy storage system. The temperature drop across the turbine (and by extension, across a thermal storage system) for the partial-cooling cycle is estimated to be 23% to 35% larger compared to the recompression cycle of equal recuperator conductance between 5 and 15 MW/K. This reduces the size and cost of the thermal storage system. Simulations by NREL and Abengoa Solar indicate the partial-cooling cycle results in a lower LCOE compared with the recompression cycle, despite the former's slightly lower cycle efficiency. Advantages of the recompression cycle include higher thermal efficiency and potential for a smaller precooler. The overall impact favors the use of a partial-cooling cycle for CSP compared to the more commonly analyzed recompression cycle.

  20. The New Sunspot-Number Index and Solar-Cycle Characteristics

    NASA Astrophysics Data System (ADS)

    Carrasco, V. M. S.; Aparicio, A. J. P.; Vaquero, J. M.; Gallego, M. C.

    2016-10-01

    We revisit several characteristics of the solar cycle using the new version of the sunspot-number index. Thus, we calculated several correlations, including the recent Solar Cycles 23 and 24 in the analysis. We applied two smoothing methods to the sunspot number: i) the usual 13-month running mean and ii) a 24-month Gaussian filter. Each of these methods contains two analyses: on the one hand, we consider all of the solar cycles available, and on the other hand, only those from Solar Cycle 10 onward. It can be seen that this new version improves or yields similar results for the correlations with respect to other works using the old version of the sunspot number, except for the amplitude-descending time effect and the linear fit of the secular trend. However, employing the same methodology in the analysis and considering the same solar cycles, it can be seen that the new sunspot number, in general, does not improve the correlations with respect to the old sunspot number and, moreover, the correlations obtained with the Gaussian filter generally are stronger than those with the 13-month running mean. Furthermore, from a sinusoidal fit to the solar-maximum amplitudes of the whole series, we have obtained a periodicity of the Gleissberg cycle equal to 97.7 years ( {≈} 8.9 solar cycles) for the 13-month running mean and 99.8 years ( {≈} 9.1 solar cycles) for the Gaussian filter. Lastly, the Waldmeier effect, the modified Waldmeier effect, the amplitude-period effect, the amplitude-minimum effect, and the even-odd effect are characteristics with high correlation coefficients and significance levels; the sinusoidal fit applied to the solar-maximum amplitudes yields a lower correlation coefficient value but a high significance level; and both the amplitude-descending-time effect and secular trend of the solar activity have weaker correlation coefficients and significance levels.

  1. Flexible thermal cycle test equipment for concentrator solar cells

    DOEpatents

    Hebert, Peter H.; Brandt, Randolph J.

    2012-06-19

    A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

  2. The response of chemistry and climate to the 11-year solar cycle in UM-UKCA

    NASA Astrophysics Data System (ADS)

    Bednarz, Ewa; Telford, Paul; Maycock, Amanda; Abraham, Luke; Braesicke, Peter; Pyle, John

    2014-05-01

    It is now generally agreed that the UV variability associated with the 11-year solar cycle leads to changes in ozone and temperature in the upper stratosphere. In addition, a range of observational and modelling studies suggest that such changes are the starting point for a chain of processes (including feedbacks) resulting in circulation changes in many areas of the atmosphere. However, precise details of the interactions between chemistry and meteorology induced by solar variability remain under question. In our study, we use a version of the UM-UKCA chemistry-climate model with consistent spectrally-resolved solar variability. While the solar cycle in heating rates has been applied with the method used in HadGEM2-ES, fine spectrally-resolved solar variability has been uniquely incorporated into the Fast-JX photolysis scheme. We perform two 50-year-long perpetual year solar maximum and solar minimum integrations and complement them with a three member ensemble of a transient 1960-2010 integration in which boundary conditions correspond by and large to the CCMI Ref-C1 scenario. We show how the inferred solar signals vary between the individual experiments. This indicates high natural variability and the resulting contamination of the solar signal with contributions from other processes as well as the existence of possible non-linearities between the solar cycle and other atmospheric forcings. Therefore, we highlight that long data series are needed to ensure correct attribution of the modelled and observed anomalies. In addition, we present results from two perpetual year experiments in which the solar cycle was applied exclusively in either short-wave heating or photolysis. We find large non-linearities in the modelled anomalies as compared to the realistic integration with both modulations included. This highlights the subtle nature of the dynamical response to the solar cycle forcing and indicates the need for interactive chemistry with a detailed photolysis

  3. Joseph Henry and John Henry Lefroy A common 19th century vision of auroral research

    NASA Astrophysics Data System (ADS)

    Silverman, S. M.

    Research on solar-terrestrial relationships today relies primarily on in situ space data. These data, however, cover only a short period of about 30 years. Many solar and related phenomena vary on much longer time scales. For the study of these, parameters such as sunspots, magnetic activity, auroral occurrence, or other proxy data are required. Historical records of aurora are particularly useful in this connection.

  4. The Divergence of CME and Sunspot Number Rates During Solar Cycle 24

    NASA Astrophysics Data System (ADS)

    Webb, David F.; St. Cyr, Orville Chris; Xie, Hong; Kuchar, Thomas Andrew

    2014-06-01

    In the previous three solar cycles the frequency of occurrence of CMEs observed in white light has closely tracked the solar cycle in both phase and amplitude, varying by an order of magnitude over the cycle. LASCO has now observed the entire solar Cycle 23 and continues to observe through the current rise and maximum phases of Cycle 24. Cycle 23 had an unusually long decline and extended minimum. During this period we have been able to image and count CMEs in the heliosphere, and can determine rates from both LASCO and STEREO SECCHI (since 2007) coronagraphs and from the Solar Mass Ejection Imager (SMEI - since 2003) and the SECCHI Heliospheric Imagers in the heliosphere. Manual rates estimated by observers are now supplemented by counts from identifications made by automatic programs, such as contained in the SEEDS, CACTus and ARTEMIS catalogs. Since the cycle 23/24 minimum, the CME and sunspot number rates have diverged, with similar cycle 23/24 rise and peak CME rates but much lower SSN rates in this cycle. We will discuss these rate estimates and their implications for the evolution of the global solar magnetic field.

  5. Solar cycle variations in ion composition in the dayside ionosphere of Titan

    NASA Astrophysics Data System (ADS)

    Madanian, H.; Cravens, T. E.; Richard, M. S.; Waite, J. H.; Edberg, N. J. T.; Westlake, J. H.; Wahlund, J.-E.

    2016-08-01

    One Titanian year spans over two complete solar cycles, and the solar irradiance has a significant effect on ionospheric densities. Solar cycle 24 has been one of the quietest cycles on record. In this paper we show data from the Cassini ion and neutral mass spectrometer (INMS) and the radio and plasma wave science Langmuir probe spanning the time period from early 2005, at the declining phase of solar cycle 23, to late 2015 at the declining phase of solar cycle 24. Densities of different ion species measured by the INMS show a consistent enhancement for high solar activity, particularly near the ionospheric peak. The density enhancement is best seen in primary ion species such as CH3+ rather than heavier ion species such as HCNH+. Unlike at Earth, where the ionosphere and atmosphere thermally expand at high solar activity, at Titan the altitude of the ionospheric peak decreases, indicating that the underlying neutral atmosphere was less extensive. Among the major ion species, CH5+ shows the largest decrease in peak altitude, whereas heavy ions such as C3H5+ show very little decrease. We also calculate the ion production rates using a theoretical model and a simple empirical model using INMS data and show that these effectively predict the increased ion production rates at high solar activity.

  6. Solar Cycle Effects on the Heliospheric Interface and Related Energetic Neutral Atom Production

    NASA Astrophysics Data System (ADS)

    Pogorelov, N. V.; Heerikhuisen, J.; Borovikov, S.; Ebert, R. W.; Suess, S. T.; Zank, G. P.

    2013-05-01

    Solar cycle has a profound influence on the solar wind (SW) interaction with the local interstellar medium (LISM) on more than one time scales. Also, there are substantial differences in individual solar cycle lengths and SW behavior within them. The presence of a slow SW belt, with a variable latitudinal extent changing within each solar cycle from rather small angles to 90 degrees, separated from the fast wind that originates at coronal holes substantially affects plasma at the heliospheric interface, in the compressed plasma layers ahead of and behind the heliopause. The solar cycle may be the reason of the complicated flow structure being observed in the inner heliosheath by Voyager 1. We present the results of the solar cycle simulations based on different numerical models, including the model with the SW boundary conditions derived from Ulysses measurements, and demonstrate how they can explain the observations of small to negative SW radial velocity components at Voyager 1, as well as an abrupt decrease in the ACR flux. Related changes in the ENA flux throughout the solar cycle are also discussed in the context of IBEX measurements.

  7. The solar cycle dependence of the location and shape of the Venus bow shock

    SciTech Connect

    Zhang, T.L.; Luhmann, J.G.; Russell, C.T. )

    1990-09-01

    From initial Pioneer Venus observations during the maximum of solar cycle 21 it was evident that the position of the Venus bow shock varies with solar activity. The bow shock radius in the terminator plane changed from 2.4 R{sub v} to 2.1 R{sub v} as solar activity went from maximum to minimum and, as activity has increased in cycle 22, it has increased again. The recent studies of the subsolar region show that the altitude of the nose of the bow shock varies from 1,600 km at solar minimum to 2,200 km at intermediate solar activity in concert with the terminator altitude so that the shape remains constant and only the size varies during the solar cycle. Using a gas dynamic model and the observed bow shock location, the authors infer the variation in the size of the effective obstacle during the solar cycle. At solar maximum, the effective obstacle is larger than the ionopause as if a magnetic barrier exists in the inner magnetosheath. This magnetic barrier acts as the effective obstacle deflecting the magnetosheath plasma about 500 km above the surface of Venus. However, at solar minimum the effective obstacle is well below the subsolar ionopause, and some absorption of the solar wind plasma by the Venus neutral atmosphere is suggested by these observations. The dependence of the solar cycle variation of the shock position on the orientation of the interplanetary magnetic field reinforces the idea that planetary ion pickup is important in the interaction of the solar wind with Venus.

  8. Influence of the Schwabe/Hale solar cycles on climate change during the Maunder Minimum

    NASA Astrophysics Data System (ADS)

    Miyahara, Hiroko; Yokoyama, Yusuke; Yamaguchi, Yasuhiko T.

    2010-02-01

    We have examined the variation of carbon-14 content in annual tree rings, and investigated the transitions of the characteristics of the Schwabe/Hale (11-year/22-year) solar and cosmic-ray cycles during the last 1200 years, focusing mainly on the Maunder and Spoerer minima and the early Medieval Maximum Period. It has been revealed that the mean length of the Schwabe/Hale cycles changes associated with the centennial-scale variation of solar activity level. The mean length of Schwabe cycle had been ~14 years during the Maunder Minimum, while it was ~9 years during the early Medieval Maximum Period. We have also found that climate proxy record shows cyclic variations similar to stretching/shortening Schwabe/Hale solar cycles in time, suggesting that both Schwabe and Hale solar cycles are playing important role in climate change. In this paper, we review the nature of Schwabe and Hale cycles of solar activity and cosmic-ray flux during the Maunder Minimum and their possible influence on climate change. We suggest that the Hale cycle of cosmic rays are amplified during the grand solar minima and thus the influence of cosmic rays on climate change is prominently recognizable during such periods.

  9. Using Polar Coronal Hole Area Measurements to Determine the Solar Polar Magnetic Field Reversal in Solar Cycle 24

    NASA Technical Reports Server (NTRS)

    Karna, N.; Webber, S.A. Hess; Pesnell, W.D.

    2014-01-01

    An analysis of solar polar coronal hole (PCH) areas since the launch of the Solar Dynamics Observatory (SDO) shows how the polar regions have evolved during Solar Cycle 24. We present PCH areas from mid-2010 through 2013 using data from the Atmospheric Imager Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) instruments onboard SDO. Our analysis shows that both the northern and southern PCH areas have decreased significantly in size since 2010. Linear fits to the areas derived from the magnetic-field properties indicate that, although the northern hemisphere went through polar-field reversal and reached solar-maximum conditions in mid-2012, the southern hemisphere had not reached solar-maximum conditions in the polar regions by the end of 2013. Our results show that solar-maximum conditions in each hemisphere, as measured by the area of the polar coronal holes and polar magnetic field, will be offset in time.

  10. Thermal cycle testing of Space Station Freedom solar array blanket coupons

    NASA Technical Reports Server (NTRS)

    Scheiman, David A.; Schieman, David A.

    1991-01-01

    Lewis Research Center is presently conducting thermal cycle testing of solar array blanket coupons that represent the baseline design for Space Station Freedom. Four coupons were fabricated as part of the Photovoltaic Array Environment Protection (PAEP) Program, NAS 3-25079, at Lockheed Missile and Space Company. The objective of the testing is to demonstrate the durability or operational lifetime of the solar array welded interconnect design within the durability or operational lifetime of the solar array welded interconnect design within a low earth orbit (LEO) thermal cycling environment. Secondary objectives include the observation and identification of potential failure modes and effects that may occur within the solar array blanket coupons as a result of thermal cycling. The objectives, test articles, test chamber, performance evaluation, test requirements, and test results are presented for the successful completion of 60,000 thermal cycles.

  11. On the Influence of the Solar Bi-Cycle on Comic Ray Modulatio

    NASA Astrophysics Data System (ADS)

    Lifter, N. Part Xxvii: A. Defect Of The Solar Dynamo. B.; Scissors, K.; Sprucener, H.

    In this presentation we propose a new paradigm that explains the different lengths of individual solar Hale cycles. It proves beneficial to distinguish between a so-called inHale and ex-Hale cycle, which together form the solar bi-cycle. We carefully analyzed the influence of so-called complex mode excitations (CMEs) on comic ray modulation, in particular on the drifts of the comic isotope O+3 , which we found to induce characteristic anisotropies. This comic isotope anisotropy (CIA) is caused by the wellknown north-south asymmetry (NSA) and can be observed as a rare Forbush increase (FBI). The latter is linked to the solar magnetic field which appears to have a chaotic behaviour (for details see part I-XXVI). Especially during an ex-Hale cycle magnetic flux is pseudo-pneumatically escaping through a coronal hole. Consequently, the solar dynamo can no longer operate efficiently, i.e. is defect.

  12. The Variability of Solar Spectral Irradiance and Solar Surface Indices Through the Solar Activity Cycles 21-23

    NASA Astrophysics Data System (ADS)

    Deniz Goker, Umit

    2016-07-01

    A study of variations of solar spectral irradiance (SSI) in the wavelength ranges 121.5 nm-300.5 nm for the period 1981-2009 is presented. We used various data for ultraviolet (UV) spectral lines and international sunspot number (ISSN) from interactive data centers as SME (NSSDC), UARS (GDAAC), SORCE (LISIRD) and SIDC, respectively. We developed a special software for extracting the data and reduced this data by using the MATLAB. In this respect, we revealed negative correlations of intensities of UV (289.5 nm-300.5 nm) emission lines originating in the solar chromosphere with the ISSN index during the unusually prolonged minimum between the solar cycles (SCs) 23 and 24. We also compared our results with the ground-based telescopes as Solar Irradiance Platform, Stanford Data (SFO), Kodaikanal Data (KKL) and NGDC Homepage (Rome and Learmonth Solar Observatories). We studied the variations of total solar irradiance (TSI), magnetic field, sunspots/sunspot groups, Ca II K-flux, faculae and plage areas data with these ground-based telescopes, respectively. We reduced the selected data using the Phyton programming language and plot with the IDL programme. Therefore, we found that there was a decrease in the area of bright faculae and chromospheric plages while the percentage of dark faculae and plage decrease, as well. However, these decreases mainly occurred in small sunspots, contrary to this, these terms in large sunspot groups were comparable to previous SCs or even larger. Nevertheless, negative correlations between ISSN and SSI data indicate that these emissions are in close connection with the classes of sunspots/sunspot groups and "PLAGE" regions. Finally, we applied the time series of the chemical elements correspond to the wavelengths 121.5 nm-300.5 nm and compared with the ISSN data. We found an unexpected increasing in the 298.5 nm for the Fe II element. The variability of Fe II (298.5 nm) is in close connection with the plage regions and the sizes of the

  13. Long-Range Solar Activity Predictions: A Reprieve from Cycle #24's Activity

    NASA Technical Reports Server (NTRS)

    Richon, K.; Schatten, K.

    2003-01-01

    We discuss the field of long-range solar activity predictions and provide an outlook into future solar activity. Orbital predictions for satellites in Low Earth Orbit (LEO) depend strongly on exospheric densities. Solar activity forecasting is important in this regard, as the solar ultra-violet (UV) and extreme ultraviolet (EUV) radiations inflate the upper atmospheric layers of the Earth, forming the exosphere in which satellites orbit. Rather than concentrate on statistical, or numerical methods, we utilize a class of techniques (precursor methods) which is founded in physical theory. The geomagnetic precursor method was originally developed by the Russian geophysicist, Ohl, using geomagnetic observations to predict future solar activity. It was later extended to solar observations, and placed within the context of physical theory, namely the workings of the Sun s Babcock dynamo. We later expanded the prediction methods with a SOlar Dynamo Amplitude (SODA) index. The SODA index is a measure of the buried solar magnetic flux, using toroidal and poloidal field components. It allows one to predict future solar activity during any phase of the solar cycle, whereas previously, one was restricted to making predictions only at solar minimum. We are encouraged that solar cycle #23's behavior fell closely along our predicted curve, peaking near 192, comparable to the Schatten, Myers and Sofia (1996) forecast of 182+/-30. Cycle #23 extends from 1996 through approximately 2006 or 2007, with cycle #24 starting thereafter. We discuss the current forecast of solar cycle #24, (2006-2016), with a predicted smoothed F10.7 radio flux of 142+/-28 (1-sigma errors). This, we believe, represents a reprieve, in terms of reduced fuel costs, etc., for new satellites to be launched or old satellites (requiring reboosting) which have been placed in LEO. By monitoring the Sun s most deeply rooted magnetic fields; long-range solar activity can be predicted. Although a degree of uncertainty

  14. Solar activity cycle and the incidence of foetal chromosome abnormalities detected at prenatal diagnosis

    NASA Astrophysics Data System (ADS)

    Halpern, Gabrielle J.; Stoupel, Eliahu G.; Barkai, Gad; Chaki, Rina; Legum, Cyril; Fejgin, Moshe D.; Shohat, Mordechai

    1995-06-01

    We studied 2001 foetuses during the period of minimal solar activity of solar cycle 21 and 2265 foetuses during the period of maximal solar activity of solar cycle 22, in all women aged 37 years and over who underwent free prenatal diagnosis in four hospitals in the greater Tel Aviv area. There were no significant differences in the total incidence of chromosomal abnormalities or of trisomy between the two periods (2.15% and 1.8% versus 2.34% and 2.12%, respectively). However, the trend of excessive incidence of chromosomal abnormalities in the period of maximal solar activity suggests that a prospective study in a large population would be required to rule out any possible effect of extreme solar activity.

  15. Amplifying the Pacific climate system response to a small 11-year solar cycle forcing.

    PubMed

    Meehl, Gerald A; Arblaster, Julie M; Matthes, Katja; Sassi, Fabrizio; van Loon, Harry

    2009-08-28

    One of the mysteries regarding Earth's climate system response to variations in solar output is how the relatively small fluctuations of the 11-year solar cycle can produce the magnitude of the observed climate signals in the tropical Pacific associated with such solar variability. Two mechanisms, the top-down stratospheric response of ozone to fluctuations of shortwave solar forcing and the bottom-up coupled ocean-atmosphere surface response, are included in versions of three global climate models, with either mechanism acting alone or both acting together. We show that the two mechanisms act together to enhance the climatological off-equatorial tropical precipitation maxima in the Pacific, lower the eastern equatorial Pacific sea surface temperatures during peaks in the 11-year solar cycle, and reduce low-latitude clouds to amplify the solar forcing at the surface.

  16. Amplifying the Pacific climate system response to a small 11-year solar cycle forcing.

    PubMed

    Meehl, Gerald A; Arblaster, Julie M; Matthes, Katja; Sassi, Fabrizio; van Loon, Harry

    2009-08-28

    One of the mysteries regarding Earth's climate system response to variations in solar output is how the relatively small fluctuations of the 11-year solar cycle can produce the magnitude of the observed climate signals in the tropical Pacific associated with such solar variability. Two mechanisms, the top-down stratospheric response of ozone to fluctuations of shortwave solar forcing and the bottom-up coupled ocean-atmosphere surface response, are included in versions of three global climate models, with either mechanism acting alone or both acting together. We show that the two mechanisms act together to enhance the climatological off-equatorial tropical precipitation maxima in the Pacific, lower the eastern equatorial Pacific sea surface temperatures during peaks in the 11-year solar cycle, and reduce low-latitude clouds to amplify the solar forcing at the surface. PMID:19713524

  17. ON POSSIBLE VARIATIONS OF BASAL Ca II K CHROMOSPHERIC LINE PROFILES WITH THE SOLAR CYCLE

    SciTech Connect

    Pevtsov, Alexei A.; Uitenbroek, Han; Bertello, Luca E-mail: huitenbroek@nso.edu

    2013-04-10

    We use daily observations of the Ca II K line profiles of the Sun-as-a-star taken with the Integrated Sunlight Spectrometer from 2006 December through 2011 July to deconvolve the contributions from the quiet (basal) chromosphere and with magnetic network/plage areas. The 0.5 A emission index computed from basal profiles shows a significantly reduced modulation (as compared with one derived from the observed profiles) corresponding to the Sun's rotation. For basal contribution of the Ca II K line, the peak in power spectrum corresponding to solar rotation is broad and not well defined. Power spectra for the plage contribution show two narrow well-defined peaks corresponding to solar rotation at two distinct latitudes, in agreement with the latitudinal distribution of activity on the Sun at the end of Cycle 23 and beginning of Cycle 24. We use the lack of a signature of solar rotation in the basal (quiet Sun) component as an indication of a successful removal of the active Sun (plage) component. Even though the contribution from solar activity is removed from the basal line profiles, we find a weak dependency of intensity in the line core (K3) of basal profiles with the phase of the solar cycle. Such dependency could be the result of changes in thermal properties of basal chromosphere with the solar cycle. As an alternative explanation, we also discuss a possibility that the basal component does not change with the phase of the solar cycle.

  18. Observations of Solar Spectral Irradiance Change During Cycle 22 from NOAA-9 SBUV/2

    NASA Technical Reports Server (NTRS)

    DeLand, Matthew T.; Cebula, Richard P.; Hilsenrath, Ernest

    2003-01-01

    The NOM-9 Solar Backscatter Ultraviolet, model 2 (SBUV/2) instrument is one of a series of instruments providing daily solar spectral irradiance measurements in the middle and near ultraviolet since 1978. The SBUV/2 instruments are primarily designed to measure stratospheric profile and total column ozone, using the directional albedo as the input to the ozone processing algorithm. As a result, the SBUV/2 instrument does not have onboard monitoring of all time-dependent response changes. We have applied internal comparisons and vicarious (external) comparisons to determine the long-term instrument characterization for NOAA-9 SBUV/2 to derive accurate solar spectral irradiances from March 1985 to May 1997 spanning two solar cycle minima with a single instrument. The NOAA-9 data show an amplitude of 9.3(+/- 2.3)% (81-day averaged) at 200-205 nm for solar cycle 22. This is consistent with the result of (Delta)F(sub 200-205) = 8.3(+/- 2.6)% for cycle 21 from Nimbus-7 SBUV and (Delta)F(sub 200-205) = 10(+/- 2)% (daily values) for cycle 23 from UARS SUSIM. NOAA-9 data at 245-250 nm show a solar cycle amplitude of (Delta)F(sub 245-250) = 5.7(+/- 1.8)%. NOAA-9 SBUV/2 data can be combined with other instruments to create a 25-year record of solar UV irradiance.

  19. Relationships between solar activity and climate change. [sunspot cycle effects on lower atmosphere

    NASA Technical Reports Server (NTRS)

    Roberts, W. O.

    1974-01-01

    Recurrent droughts are related to the double sunspot cycle. It is suggested that high solar activity generally increases meridional circulations and blocking patterns at high and intermediate latitudes, especially in winter. This effect is related to the sudden formation of cirrus clouds during strong geomagnetic activity that originates in the solar corpuscular emission.

  20. The temperature of quiescent streamers during solar cycles 23 and 24

    SciTech Connect

    Landi, E.; Testa, P.

    2014-05-20

    Recent in-situ determinations of the temporal evolution of the charge state distribution in the fast and slow solar wind have shown a general decrease in the degree of ionization of all the elements in the solar wind along solar cycles 23 and 24. Such a decrease has been interpreted as a cooling of the solar corona which occurred during the decline and minimum phase of solar cycle 23 from 2000 to 2010. In the present work, we investigate whether spectroscopic determinations of the temperature of the quiescent streamers show signatures of coronal plasma cooling during cycles 23 and 24. We measure the coronal electron density and thermal structure at the base of 60 quiescent streamers observed from 1996 to 2013 by SOHO/SUMER and Hinode/EIS and find that both quantities do now show any significant dependence on the solar cycle. We argue that if the slow solar wind is accelerated from the solar photosphere or chromosphere, the measured decrease in the in-situ wind charge state distribution might be due to an increased efficiency in the wind acceleration mechanism at low altitudes. If the slow wind originates from the corona, a combination of density and wind acceleration changes may be responsible for the in-situ results.

  1. Effects of Solar UV Radiation and Climate Change on Biogeochemical Cycling: Interactions and Feedbacks

    EPA Science Inventory

    Solar UV radiation, climate and other drivers of global change are undergoing significant changes and models forecast that these changes will continue for the remainder of this century. Here we assess the effects of solar UV radiation on biogeochemical cycles and the interactions...

  2. Life Cycle Greenhouse Gas Emissions from Solar Photovoltaics (Fact Sheet)

    SciTech Connect

    Not Available

    2012-11-01

    The National Renewable Energy Laboratory (NREL) recently led the Life Cycle Assessment (LCA) Harmonization Project, a study that helps to clarify inconsistent and conflicting life cycle GHG emission estimates in the published literature and provide more precise estimates of life cycle GHG emissions from PV systems.

  3. Anomalous Expansion of Coronal Mass Ejections During Solar Cycle 24 and Its Space Weather Implications

    NASA Technical Reports Server (NTRS)

    Gopalswamy, Nat; Akiyama, Sachiko; Yashiro, Seiji; Xie, Hong; Makela, Pertti; Michalek, Grzegorz

    2014-01-01

    The familiar correlation between the speed and angular width of coronal mass ejections (CMEs) is also found in solar cycle 24, but the regression line has a larger slope: for a given CME speed, cycle 24 CMEs are significantly wider than those in cycle 23. The slope change indicates a significant change in the physical state of the heliosphere, due to the weak solar activity. The total pressure in the heliosphere (magnetic + plasma) is reduced by approximately 40%, which leads to the anomalous expansion of CMEs explaining the increased slope. The excess CME expansion contributes to the diminished effectiveness of CMEs in producing magnetic storms during cycle 24, both because the magnetic content of the CMEs is diluted and also because of the weaker ambient fields. The reduced magnetic field in the heliosphere may contribute to the lack of solar energetic particles accelerated to very high energies during this cycle.

  4. ON THE VARIATION OF SOLAR RADIUS IN ROTATION CYCLES

    SciTech Connect

    Qu, Z. N.; Kong, D. F.; Xiang, N. B.; Feng, W.

    2015-01-10

    The Date Compensated Discrete Fourier Transform and CLEANest algorithm are used to study the temporal variations of the solar radius observed at Rio de Janeiro Observatory from 1998 March 2 to 2009 November 6. The CLEANest spectra show several significant periodicities around 400, 312, 93.5, 86.2, 79.4, 70.9, 53.2, and 26.3 days. Then, combining the data on the daily solar radius measured at Calern Observatory and Rio de Janeiro Observatory and the corresponding daily sunspot areas, we study the short-term periodicity of the solar radius and the role of magnetic field in the variation of the solar radius. The rotation period of the daily solar radius is determined to be statistically significant. Moreover, its temporal evolution is anti-phase with that of sunspot activity, and it is found anti-phase with solar activity. Generally, the stronger solar activity is, the more obvious is the anti-phase relation of radius with solar activity. This indicates that strong magnetic fields have a greater inhibitive effect than weak magnetic fields on the variation of the radius.

  5. Solar cycle variations in the neutral exosphere inferred from the location of the Venus bow shock

    NASA Technical Reports Server (NTRS)

    Russell, C. T.; Chou, E.; Luhmann, J. G.; Brace, L. H.

    1990-01-01

    Solar UV and EUV varies significantly during the solar cycle. Pioneer Venus can measure this variation both directly and indirectly. A direct measure of the EUV is obtained from the photoelectron current of the Langmuir probe when the spacecraft is in the solar wind. The indirect measure is by monitoring the location of the Venus bow shock. The UV and EUV both heat the upper atmosphere and ionize it. When solar activity is high, the upper atmosphere should be ionized more rapidly. This effect adds a greater number of planetary ions to the magnetosheath plasma as it flows by Venus. It is this increase in mass flow that causes the Venus bow shock to move away from its solar minimum location. Pioneer Venus has now monitored the location of the bow shock for an entire solar cycle. The bow shock location is well correlated with the variation in EUV flux as measured by the Langmuir probe. The bow shock is farther from Venus than expected from the sunspot number or 10.7 cm solar radio flux, indicating that solar UV radiation may be even stronger at the present time than would be predicted from the relationships determined during the previous solar cycle.

  6. Properties of the suprathermal heavy ion population near 1 AU during solar cycles 23 and 24

    NASA Astrophysics Data System (ADS)

    Dayeh, Maher A.; Desai, Mihir I.; Ebert, Robert W.; Mason, Glenn M.

    2016-03-01

    Using measurements from the Advanced Composition Explorer/Ultra-Low Energy Isotope Spectrometer (ACE/ULEIS) near 1 AU, we surveyed the composition and spectra of heavy ions (He-through-Fe) during interplanetary quiet times from 1998 January 1 to 2014 December 31 at suprathermal energies between ˜0.11 and ˜1.28 MeV nucleon-1. The selected time period covers the maxima of solar cycles 23 and 24 and the extended solar minimum in between. We find the following: (1) The number of quiet-hours in each year correlates well with the sunspot number, year 2009 was the quietest for about 90% of the time; (2) The composition of the quiet-time suprathermal heavy ion population (3He, C-through-O, and Fe) correlates well with the level of solar activity, exhibiting SEP-like composition signatures during solar maximum, and CIR- or solar wind-like composition during solar minimum; (3) The heavy ion spectra at ˜0.11-0.32 MeV nucleon-1 exhibit suprathermal tails with power-law spectral indices ranging from 1.4 to 2.7. (4) Fe spectral indices get softer (steeper) from solar minimum of cycle 23 to solar cycle 24 maximum. These results imply that during IP quiet times and at energies above ˜0.1 MeV nucleon-1, the IP medium is dominated by material from prior solar and interplanetary events.

  7. The role of ozone feedback in modulating the atmospheric response to the solar cycle forcing

    NASA Astrophysics Data System (ADS)

    Bednarz, Ewa; Maycock, Amanda; Braesicke, Peter; Telford, Paul; Abraham, Luke; Pyle, John

    2016-04-01

    The irradiance changes between the 11-year solar cycle maximum and minimum lead to increased stratospheric temperatures via enhanced UV absorption by ozone. This direct radiative response is strengthened by increased photochemical ozone production. While in reality these two processes are closely coupled, not all global climate models include interactive chemistry and may not therefore represent the solar-ozone feedback in an internally consistent manner. This study investigates the role of the representation of ozone for the modeled solar cycle response. We use a version of the UM-UKCA chemistry-climate model. We perform a 64-year perpetual solar minimum integration with non-interactive treatment of ozone, i.e. where ozone is externally prescribed for the radiative calculations. This is complemented with two analogous non-interactive solar maximum integrations that include an increase in solar irradiance, but which differ in their representation of the solar ozone response. We show that the representation of the solar-ozone feedback has a first-order impact on the simulated yearly mean short wave heating rates and temperature responses to the 11-year solar cycle forcing. However, despite the substantial differences in the tropical temperature changes, the Northern Hemisphere high latitude circulation responses are broadly similar in both experiments, and show strengthening of the polar vortex during winter and a weakening in March. Therefore, the representation of the prescribed solar-ozone response appears unlikely to explain the substantial spread in the solar cycle dynamical responses in different models. Lastly, we compare these results with an analogous solar maximum/minimum pair in which ozone is calculated by the photochemical scheme in a self-consistent manner. We show that the use of interactive vs non-interactive treatment of ozone does not strongly affect the yearly mean tropical temperature response. However, the results suggest potential differences

  8. Nitrogen, land and water inputs in changing cattle farming systems. A historical comparison for France, 19th-21st centuries.

    PubMed

    Chatzimpiros, Petros; Barles, Sabine

    2010-09-15

    This paper provides an original account of the long-term regional metabolism in relation to the cattle rearing in western France starting by the precise formulation of animal diets at three key dates of the 19th, 20th and 21st centuries. We established links between the demand in fodder of the meat and dairy sectors and the necessary inputs of nitrogen, water and land as well as the land cover changes occurring on the affected local and remote cattle acreage. The average agricultural productivity for fodder supply is estimated at about 50 kg N/ha in the mid-19th, 54 kg N/ha in the early 20th and 150 kg N/ha at the turning of the 21st century. Jointly for the dairy and meat productions, the potential efficiency in the conversion of the vegetal into animal protein more than doubled over the studied period, passing from less than 9% in the 19th to 20% in the 21st century. The current cattle sector is sustained for about 25% by land situated beyond the regional frontiers and uses water at intensities that approach or exceed the availability of renewable water. The nitrogen pollution is expressed in terms of the Net Anthropogenic Nitrogen Inputs (NANI) and, by comparison to the N recovered in products, is used to define the N-Environmental Efficiency of the farming. We discuss the historical succession of the factors that contributed to the growth of the meat and milk production and make a comparison of the impacts and policy between the local and distant resources.

  9. An archival exploration of homicide--suicide and mass murder in the context of 19th-century American parricides.

    PubMed

    Shon, Phillip Chong Ho; Roberts, Michael A

    2010-02-01

    There has been little attempt to integrate contemporary studies of suicide and mass murder to homicide-suicides. The current research attempts to do so in the context of 19th-century parricides in America. This project uses archival records from The New York Times and the Chicago Tribune, 1851-1899, resulting in a total of 231 incidents. Our results indicate that parricides, mass murders, and suicides tended to originate as spontaneous acts, usually during the course of an argument, gathering momentum as the interaction unfolded. We contend that suicide is one way of alleviating threats to offender's loss of self-identity.

  10. [The gynacological treatment of mental illnesses: a response to the psychiatric nihilism of the 19th century].

    PubMed

    Balbo, E A

    1993-01-01

    This study analizes differents gynacological treatments of mental illnesses throughout the 19th century. The autor reaches the conclusion, via the professional activity of the English surgeon Isaac Baker Brown, that these gynological treaments were really the result of the confluence of a series of factors: the development of the insanity reflex theory, the consideration of Woman as the pathological prisioner of her genitality, the pessimistic vision of mental illness based on the theory of degeneration, the lack of therapeutic resources in mental medicine and, finally, the marked competition of Victorian doctors amongst themselves and also their profit motive, disguised and hidden under the welcoming cloak of a hypocritical medical morale.

  11. Causes of mortality due to rheumatic diseases in Jerez de los Caballeros (Badajoz) during the 19th century.

    PubMed

    Peral Pacheco, Diego; Suárez-Guzmán, Francisco Javier

    2016-01-01

    A total of 26,203 of the deaths in Jerez de los Caballeros (Badajoz) during the 19th century were collected and grouped according to the Bertillon's Classification, in order to study the causes of death from rheumatic diseases. An analysis was made using the Death Registers, those located in the Parish Archives, and files of the Municipal Archives. There were a total of 31 deaths due to rheumatic diseases, with the 65-74 years age group being most frequent. The lack of records may be due to the inaccuracy of the diagnoses. September was the month of increased mortality.

  12. An early 19th-century Canadian surgical practice: the casebook of John Mackieson of Charlottetown, 1795–1885

    PubMed Central

    Shephard, David A.E.; Grogono, Basil J.S.

    2002-01-01

    A casebook written by Dr. John Mackieson (1795–1885), of Charlottetown, contains the records of 49 surgical cases he managed between 1826 and 1857. In view of the rarity of first-hand accounts of surgical practice in Canada in the mid-19th century, Mackieson’s case records are a significant source of information. These cases are discussed in order to delineate Mackieson’s approach to the surgical problems he faced in his general practice. His case records also illustrate some of the general problems that beset surgeons in that era. PMID:11939660

  13. The influence of inequality on the standard of living: worldwide anthropometric evidence from the 19th and 20th centuries.

    PubMed

    Blum, Matthias

    2013-12-01

    We provide empirical evidence on the existence of the Pigou-Dalton principle. The latter indicates that aggregate welfare is - ceteris paribus - maximized when incomes of all individuals are equalized (and therefore marginal utility from income is as well). Using anthropometric panel data on 101 countries during the 19th and 20th centuries, we determine that there is a systematic negative and concave relationship between height inequality and average height. The robustness of this relationship is tested by means of several robustness checks, including two instrument variable regressions. These findings help to elucidate the impact of economic inequality on welfare. PMID:23352274

  14. A search for the solar roots of the most disturbed interplanetary field intervals of solar cycle 21

    NASA Technical Reports Server (NTRS)

    Luhmann, J. G.; Russell, C. T.; Barnes, A.

    1989-01-01

    During the course of the Pioneer Venus Orbiter mission, fairly continuous interplanetary plasma and magnetic field data were obtained which span the interval from prior to the last solar maximum to the current solar minimum recovery. Within this nearly complete solar cycle interval, several periods of exceptional disturbance of the interplanetary field stand out. The available solar data have been examined to determine what features, if any, distinguish these periods. Neither flare nor coronal mass ejection reports show particularly unusual behavior. However, these periods appear to occur in conjunction with marked changes in the interplanetary sector structure. This suggests that heliospheric current sheet reconfiguration is an indicator of the level of interplanetary disturbance distinct from the more traditional solar activity data.

  15. Estimates of the neutron emission during large solar flares in the rising and maximum period of solar cycle 24

    NASA Astrophysics Data System (ADS)

    Lopez, D.; Matsubara, Y.; Muraki, Y.; Sako, T.; Valdés-Galicia, J. F.

    2016-03-01

    We searched for solar neutrons using the data collected by six detectors from the International Network of Solar Neutron Telescopes and one Neutron Monitor between January 2010 and December 2014. We considered the peak time of the X-ray intensity of thirty five ≥ X1.0 class flares detected by GOES satellite as the most probable production time of solar neutrons. We prepared a light-curve of the solar neutron telescopes and the neutron monitor for each flare, spanning ± 3 h from the peak time of GOES. Based on these light curves, we performed a statistical analysis for each flare. Setting a significance level at greater than 3σ, we report that no statistically significant signals due to solar neutrons were found. Therefore, upper limits are determined by the background level and solar angle of these thirty five solar flares. Our calculation assumed a power-law neutron energy spectrum and an impulsive emission profile at the Sun. The estimated upper limits of the neutron emission are consistent within the order of magnitude of the successful detections of solar neutrons made in solar cycle 23.

  16. Solar cycle variations in the ionosphere of Mars as seen by multiple Mars Express data sets

    NASA Astrophysics Data System (ADS)

    Sánchez-Cano, B.; Lester, M.; Witasse, O.; Milan, S. E.; Hall, B. E. S.; Cartacci, M.; Peter, K.; Morgan, D. D.; Blelly, P.-L.; Radicella, S.; Cicchetti, A.; Noschese, R.; Orosei, R.; Pätzold, M.

    2016-03-01

    The response of the Martian ionosphere to solar activity is analyzed by taking into account variations in a range of parameters during four phases of the solar cycle throughout 2005-2012. Multiple Mars Express data sets have been used (such as Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) in Active Ionospheric Sounding, MARSIS subsurface, and MaRS Radio Science), which currently cover more than 10 years of solar activity. The topside of the main ionospheric layer behavior is empirically modeled through the neutral scale height parameter, which describes the density distribution in altitude, and can be used as a dynamic monitor of the solar wind-Martian plasma interaction, as well as of the medium's temperature. The main peak, the total electron content, and the relationship between the solar wind dynamic pressure and the maximum thermal pressure of the ionosphere with the solar cycle are assessed. We conclude that the neutral scale height was different in each phase of the solar cycle, having a large variation with solar zenith angle during the moderate-ascending and high phases, while there is almost no variation during the moderate-descending and low phases. Between end-2007 and end-2009, an almost permanent absence of secondary layer resulted because of the low level of solar X-rays. Also, the ionosphere was more likely to be found in a more continuously magnetized state. The induced magnetic field from the solar wind, even if weak, could be strong enough to penetrate more than at other solar cycle phases.

  17. Global distribution of the solar wind and its evolution during cycles 22-24

    NASA Astrophysics Data System (ADS)

    Tokumaru, M.; Fujiki, K.; Kojima, M.; Iju, T.; Nakano, H.; Satonaka, D.; Shimoyama, T.; Hakamada, K.

    2016-03-01

    Ground-based observations of the solar wind using interplanetary scintillation (IPS) have been regularly performed since 1980s at the Solar-Terrestrial Environment Laboratory of Nagoya University using the 327-MHz multi-station system. It has been revealed from the IPS observations that the global distribution of the solar wind is well ordered by the Sun's magnetic field. This fact suggests that the magnetic field plays an important role in the formation of the solar wind. The IPS observations evidently demonstrate that global distribution of the solar wind systematically changes with the solar activity. Recently, some peculiar aspects of the solar wind have been found from the IPS observations; e.g. increase of low-latitude fast winds, global reduction of the fast wind area and the density fluctuation level, North-South asymmetry of polar fast winds. These are considered as a manifestation of weaker dynamo activity in this cycle.

  18. Solar Dynamo and the Sunspot Cycle: Current Status and Future Prospects

    NASA Astrophysics Data System (ADS)

    Nandi, Dibyendu

    2016-07-01

    Sunspots are strongly magnetized regions on the Sun's surface that have been observed for over four centuries. The number of sunspots on the solar surface waxes and wanes with an average periodicity of eleven years. The amplitude of this cycle varies and this variation governs the frequency of occurrence of solar storms, solar radiative and particulate output and the heliospheric open flux. This magnetically modulated solar activity variation has consequences for the environment of planets such as the Earth and our space and ground-based technologies. The origin of solar magnetism and its evolution is governed by a magnetohydrodynamic dynamo mechanism that relies on interactions between plasma flows and magnetic fields in the Sun's interior. In this talk I will review our current understanding of the solar dynamo mechanism, highlight outstanding issues and discuss future prospects laying particular emphasis on solar activity predictions.

  19. On the possible relations between solar activities and global seismicity in the solar cycle 20 to 23

    SciTech Connect

    Herdiwijaya, Dhani; Arif, Johan; Nurzaman, Muhamad Zamzam; Astuti, Isna Kusuma Dewi

    2015-09-30

    Solar activities consist of high energetic particle streams, electromagnetic radiation, magnetic and orbital gravitational forces. The well-know solar activity main indicator is the existence of sunspot which has mean variation in 11 years, named by solar cycle, allow for the above fluctuations. Solar activities are also related to the space weather affecting all planetary atmospheric variability, moreover to the Earth’s climate variability. Large extreme space and geophysical events (high magnitude earthquakes, explosive volcanic eruptions, magnetic storms, etc.) are hazards for humankind, infrastructure, economies, technology and the activities of civilization. With a growing world population, and with modern reliance on delicate technological systems, human society is becoming increasingly vulnerable to natural hazardous events. The big question arises to the relation between solar forcing energy to the Earth’s global seismic activities. Estimates are needed for the long term occurrence-rate probabilities of these extreme natural hazardous events. We studied connectivity from yearly seismic activities that refer to and sunspot number within the solar cycle 20 to 23 of year 1960 to 2013 (53 years). We found clear evidences that in general high magnitude earthquake events and their depth were related to the low solar activity.

  20. On the possible relations between solar activities and global seismicity in the solar cycle 20 to 23

    NASA Astrophysics Data System (ADS)

    Herdiwijaya, Dhani; Arif, Johan; Nurzaman, Muhamad Zamzam; Astuti, Isna Kusuma Dewi

    2015-09-01

    Solar activities consist of high energetic particle streams, electromagnetic radiation, magnetic and orbital gravitational forces. The well-know solar activity main indicator is the existence of sunspot which has mean variation in 11 years, named by solar cycle, allow for the above fluctuations. Solar activities are also related to the space weather affecting all planetary atmospheric variability, moreover to the Earth's climate variability. Large extreme space and geophysical events (high magnitude earthquakes, explosive volcanic eruptions, magnetic storms, etc.) are hazards for humankind, infrastructure, economies, technology and the activities of civilization. With a growing world population, and with modern reliance on delicate technological systems, human society is becoming increasingly vulnerable to natural hazardous events. The big question arises to the relation between solar forcing energy to the Earth's global seismic activities. Estimates are needed for the long term occurrence-rate probabilities of these extreme natural hazardous events. We studied connectivity from yearly seismic activities that refer to and sunspot number within the solar cycle 20 to 23 of year 1960 to 2013 (53 years). We found clear evidences that in general high magnitude earthquake events and their depth were related to the low solar activity.