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831.
K. Labitzke 《Space Science Reviews》2006,125(1-4):247-260
We have shown in several recent publications that it is necessary to group the meteorological data according to the phase
of the Quasi-Biennial Oscillation (QBO) throughout the year, in order to find a clear signal of the 11-year sunspot cycle (SSC). This work is summarized here. It is the purpose of this
paper (1) to update earlier results of the solar cycle – QBO relationship for the northern winter, (2) to stress the interaction
between the hemispheres and (3) to summarize the influence of the QBO on the solar variability signal, as well as the influence
of the solar variability signal on the QBO throughout the year. For this, the constructed annual mean of the solar cycle – QBO relationship is introduced. 相似文献
832.
New methods of local helioseismology and uninterrupted time series of solar oscillation data from the Solar and Heliospheric
Observatory (SOHO) have led to a major advance in our understanding of the structure and dynamics of active regions in the
subsurface layers. The initial results show that large active regions are formed by repeated magnetic flux emergence from
the deep interior, and that their roots are at least 50 Mm deep. The active regions change the temperature structure and flow
dynamics of the upper convection zone, forming large circulation cells of converging flows. The helioseismic observations
also indicate that the processes of magnetic energy release, flares and coronal mass ejections, might be associated with strong
(1–2 km/s) shearing flows, 4–6 Mm below the surface. 相似文献
833.
L. Bengtsson 《Space Science Reviews》2006,125(1-4):187-197
The climate response to changes in radiative forcing depends crucially on climate feedback processes, with the consequence
that solar and greenhouse gas forcing have both similar response patterns in the troposphere. This circumstance complicates
significantly the attribution of the causes of climate change. Additionally, the climate system displays a high level of unforced
intrinsic variability, and significant variations in the climate of many parts of the world are due to internal processes.
Such internal modes contribute significantly to the variability of climate system on various time scales, and thus compete
with external forcing in explaining the origin of past climate extremes. This highlights the need for independent observations
of solar forcing including long-term consistent observational records of the total and spectrally resolved solar irradiance.
The stratospheric response to solar forcing is different from its response to greenhouse gas forcing, thus suggesting that
stratospheric observations could offer the best target for the identification of the specific influence of solar forcing on
climate. 相似文献
834.
Sabri Mekaoui Steven Dewitte Christian Conscience André Chevalier 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Current measurements from DIARAD/VIRGO, PMO6V/VIRGO and ACRIM3 radiometers are of the same order of magnitude, but differ from TIM/SORCE by about 4.5 W m−2. This difference is higher than the sum of the claimed individual absolute uncertainties of the instruments. In this context, the SOLAR payload on the International Space Station embarks the SOVIM package. We give the results of the differential absolute radiometer DIARAD/SOVIM and discuss its associated uncertainties. Compared to DIARAD/VIRGO, all possible efforts have been made to improve the absolute accuracy. Substantial progress has been made in the aperture area and electrical power measurements. The measured TSI value from the left channel of DIARAD/SOVIM during three days of June 2008 is 1364.50 ± 1.38 W m−2 (Total) or ±0.49 W m−2 (if we combine the individual contributions in quadrature). The right channel gives 1364.75 W m−2 with the same uncertainties. These values are about 1.2 W m−2 lower than DIARAD/VIRGO and about 4 W m−2 higher than TIM/SORCE. The difference between the left and right channels measurements is as low as 0.25 W m−2 which is within the improved uncertainty limits. 相似文献
835.
Bryce P. Mulligan Mathew D. HunterMichael A. Persinger 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
This study replicates and extends the observations by Babayev and Allahveriyeva that changes in right hemispheric electroencephalographic activity are correlated with increases in geomagnetic activity. During the geomagnetically quiet interface between solar cycle 23 and 24 quantitative electroencephalographic (QEEG) measurements were completed for normal young adults in three separate experiments involving about 120 samples over 1.5 years. The most consistent, moderate strength correlations occurred for the changes in power within the gamma and theta ranges over the right frontal lobe. Real-time measures of atmospheric power obtained from polar orbiting satellites showed similar effects. The preferential involvement of the right frontal lobe and the regions subject to its inhibition with environmental energetic changes are consistent with the behavioural correlations historically associated with these conditions. They include increased incidence of emotional lability, erroneous reconstruction of experiences, social confrontations, and unusual perceptions. 相似文献
836.
I.V. Arkhangelskaja Yu.D. KotovA.I. Arkhangelsky A.S. Glyanenko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The count rate temporal profiles and energy spectra of the solar flares January 15, 17, 20 2005 in hard X-ray and gamma energy bands by data of AVS-F apparatus onboard CORONAS-F satellite are discussed. The energy spectra of these solar flares contain positron line and neutron capture line. Solar flares of January 17 and 20 spectra also contain some nuclear lines. Thin structure with characteristic timescales of 33–92 s is presented on flares temporal profiles in energy bands corresponding to the observed spectral features, which are confirmed by periodogram analysis (confidence level is 99%). 相似文献
837.
V.M. Velasco B. Mendoza 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
The nature of the climatic response to solar variability is assessed over a long-time scale. The wavelet analysis applied to paleoclimatic proxy data of large scale atmospheric phenomena (North Atlantic Oscillation, Atlantic Multidecadal Oscillation, Pacific Decadal Oscillation and Southern Oscillation Index) has revealed coherence between the climatic oscillations and the solar phenomena (the cosmogenic isotope 10Be and the Total Solar Irradiance) preferentially with periods of Schwabe, Hale and Yoshimura–Gleissberg cycles that may reflect a modulation of solar activity. 相似文献
838.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013,52(6):1178-1192
Starting from 2008 experimental facilities of the Aragats Space Environmental Center (ASEC) routinely measure time series of secondary cosmic ray fluxes. At these years of the minimum of solar activity we analyze the new high-energy phenomena in the terrestrial atmosphere. Namely, Thunderstorm Ground Enhancements (TGEs) and Extensive Cloud Showers (ECSs). Several new particle detectors were designed and fabricated having lower energy threshold to detect particle fluxes from the thunderclouds; some of them have possibility to distinguish charged and neutral fluxes. During 2008–2012 years ASEC detectors located at Aragats, Nor Amberd and Yerevan were detected ∼300 TGE enhancements. Amplitude of majority of them is less than 5%; however, 13 TGEs have amplitude exceeding 20%. The maximal value of observed enhancement was 271% (September 19, 2009). The paper summarizes five-years study of the TGEs on Aragats. The statistical analysis revealing the month and day-of-time distributions of TGE events, as well as the amplitude and event duration diagrams are presented. 相似文献
839.
Ye Zhang Jade Q. Clement Daila S. Gridley Larry H. Rodhe Honglu Wu 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Extrapolation of known radiation risks to the risks from low dose and low dose-rate exposures of human population, especially prolonged exposures of astronauts in the space radiation environment, relies in part on the mechanistic understanding of radiation induced biological consequences at the molecular level. While some genomic data at the mRNA level are available for cells or animals exposed to radiation, the data at the protein level are still lacking. Here, we studied protein expression profile changes using Panorama antibody microarray chips that contain antibodies to 224 proteins (or their phosphorylated forms) involved in cell signaling that included mostly apoptosis, cytoskeleton, cell cycle and signal transduction. Normal human fibroblasts were cultured until fully confluent and then exposed to 2 cGy of 150 MeV protons at high-dose rate. The proteins were isolated at 2 or 6 h after exposure and labeled with Cy3 for the irradiated cells and with Cy5 for the control samples before loading onto the protein microarray chips. The intensities of the protein spots were analyzed using ScanAlyze software and normalized by the summed fluorescence intensities and the housekeeping proteins. The results showed that low dose protons altered the expression of more than 10% of the proteins listed in the microarray analysis in various protein functional groups. Cell cycle (24%) related proteins were induced by protons and most of them were regulators of G1/S-transition phase. Comparison of the overall protein expression profiles, cell cycle related proteins, cytoskeleton and signal transduction protein groups showed significantly more changes induced by protons compared with other protein functional groups. 相似文献
840.