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Solar-climatic correlations were examined over the timescales, corresponding to solar cycles of Schwabe, Hale and Gleissberg, during the last 3–4 centuries using eight proxy and direct indices of: (a) summer climate in Fennoscandia, (b) sea surface temperature in the North Atlantic and (c) solar activity. Using novel and improved data records new evidences of a link between solar activity, North Atlantic sea surface temperature and summer temperature in Northern Fennoscandia were obtained. No solar footprint was found in the temperature proxy from East Finland. The results show that this relationship is rather complex and varies depending on the timescale considered and also varies regionally. [ABSTRACT FROM AUTHOR]

The paper presents the results of processing of data on the soft X-ray solar radiation obtained by the PINGVIN-M instrument aboard the KORONAS-FOTON spacecraft in July 2009. The high sensitivity of the device, combined with effective compensation for the magnetospheric background over most of the orbit, made it possible to study in detail the evolution of X-ray radiation from the active region and its X-ray bursts—from microflares to class-C bursts. The analyzed data refer to the period of deep minimum solar activity, during which there was only one active region emitting in the soft X-ray range on the solar disk. This made it possible to study the characteristics of soft X-ray radiation in this region without additional background with a device that records radiation from the entire solar disk, which significantly increases the reliability of the estimates of the parameters of the time and energy spectra of X-ray radiation derived from experimental data. [ABSTRACT FROM AUTHOR]

Abstract: Reconstruction of summer temperature at subarctic Fennoscandia (68°-70° N, 20°-30° E), based on tree-ring data, was compared with three solar activity reconstructions, obtained by means of 14C and 10Be. It was shown that temperature proxy reconstructs well both long-term and short-term temperature variability. Weak, but significant positive correlation between reconstructed temperature (Helama et al., 2010) averaged over 40 years, and solar proxies was found during BC 5495-AD 1895. It was shown that Hallstatt cyclicity (1800-2300 years) is the main common feature in temperature and solar proxies. Possible mechanisms of the solar-temperature link over subarctic Fennoscandia are discussed. [ABSTRACT FROM AUTHOR]

Two sets of nitrate (NO3-) concentration data in Central Greenland ice, obtained through the GISP2 collaboration and by the University of Kansas, were analyzed statistically. The two records correlate well over time scales from a few years up to a century. They both contain quasi five-year, decadal and century-type time variations. A quasi five-year periodicity resulting from increases in the mean nitrate concentration before and after maximum sunspot number was confirmed. A tendency of solar proton events to occur more frequently during the rise/dec line phases of the solar cycle may cause a quasi five-year variation. Century-type (60-110 yr) variability in nitrate outstrips the corresponding Gleissberg cycle in sunspots by 12-17 years and changes synchronously (correlates with zero phase shift) with the smoothed length of the solar Schwabe cycle. A significant correlation between century-type periodicities for nitrates in Greenland ice and northern Fennoscandian temperatures was established. The results show that despite a strong dependence on local meteorology, nitrate concentration in ice contains valuable information about global geophysical phenomena in the past. [ABSTRACT FROM AUTHOR]

A multifaceted statistical study of all available data on solar activity during the Maunder minimum (1645-1715) is presented. The data include European telescope observations, Asian sunspot observations using the unaided eye, concentrations of cosmogeneous isotopes, and catalogues of polar aurorae. Joint analyses of data on the cosmogeneous isotopes [sup 10]Be and [sup 14]C are a promising source of information on solar activity in the past. The dates of relative sunspot maxima during the Maunder minimum are consistent with the idea that there were chaotic bursts of solar activity randomly distributed in time during this interval. The available evidence that the 11-year cyclicity was preserved in 16451715 are worthy of attention but require additional deep study and verification. No convincing evidence for a 22-year periodicity of the occurrence of sunspots during the Maunder minimum has been found. [ABSTRACT FROM AUTHOR]