We use a flux transport model to simulate the evolution of the Sun’s total and open magnetic flux over the last 26 solar cycles (1713–1996). Polar field reversals are maintained by varying the meridional flow speed between 11 and 20 m s , with the poleward-directed surface flow being slower during low-amplitude cycles. If the strengths of the active regions are fixed but their numbers are taken...

This paper reports on the design and operation of a flexible power source integrating a lithium ion battery and amorphous silicon solar module, optimized to supply power to a wearable health monitoring device. The battery consists of printed anode and cathode layers based on graphite and lithium cobalt oxide, respectively, on thin flexible current collectors. It displays energy density of 6.98 ...

The purpose of this study was to examine the correlation between CR (Cosmic Ray) intensity and solar, interplanetary and terrestrial parameters. The hysteresis loops of (CR) versus those of several solar parameters showed narrow loops in even cycles 20, 22 and broad loops in odd cycles 19, 21, as also in the recent odd cycle 23. Hysteresis plots for CR versus interplanetary number density N and...

The solar activity cycle is a manifestation of the hydromagnetic dynamo working inside our star. The detection of activity cycles in solar-like stars and the study of their properties allow us to put the solar dynamo in perspective, investigating how dynamo action depends on stellar parameters and stellar structure. Nevertheless, the lack of spatial resolution and the limited time extension of ...

The astronomer A.E. Douglass is generally recognized as the founding father of dendrochronology. He studied tree rings in the search for evidence that solar variation (as seen in sunspots) is reflected in climate variation. He was convinced that his quest was successful. Analysis of some of his early data using Fourier decomposition and comparison of tree-ring periodograms with those based on k...

[1] Interplanetary magnetic field (IMF) polarity data for the years 1927–2002 were studied by wavelet analysis technique, which permits the identification of non-steady features in the IMF polarity data. It was found that the annual variation in the IMF polarity (the RosenbergColeman effect) is present only during the rise phase of solar cycles. This result is confirmed by the observed Bx (radi...

[1] We construct a solar cycle strength prediction tool by modifying a calibrated flux-transport dynamo model, and make predictions of the amplitude of upcoming solar cycle 24. We predict that cycle 24 will have a 30–50% higher peak than cycle 23, in contrast to recent predictions by Svalgaard et al. and Schatten, who used a precursor method to forecast that cycle 24 will be considerably smalle...

The present study provides a thermodynamic analysis of solar thermochemical cycles for splitting of H2O or CO2. Such cycles, powered by concentrated solar energy, have the potential to produce fuels in a sustainable way. We extend a previous study on the thermodynamics of water splitting by also taking into account CO2 splitting and the influence of the solar absorption efficiency. Based on thi...

We study the annual frequency of occurrence of intense geomagnetic storms (Dst < )100 nT) throughout the solar activity cycle for the last three cycles and ®nd that it shows di€erent structures. In cycles 20 and 22 it peaks during the ascending phase, near sunspot maximum. During cycle 21, however, there is one peak in the ascending phase and a second, higher, peak in the descending phase separ...