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We compare here the effect of geomagnetic activity (using the aa index) and sunspot activity on surface climate using sea level pressure dataset from Hadley centre during northern winter. Previous studies using the multiple linear regression method have been limited to using sunspots as a solar activity predictor. Sunspots and total solar irradiance indicate a robust positive influence around the Aleutian Low. This is valid up to a lag of one year. However, geomagnetic activity yields a positive NAM pattern at high to polar latitudes and a positive signal around Azores High pressure region. Interestingly, while there is a positive signal around Azores High for a 2-year lag in sunspots, the strongest signal in this region is found for aa index at 1-year lag. There is also a weak but significant negative signature present around central Pacific for both sunspots and aa index. The combined influence of geomagnetic activity and Quasi Biannual Oscillation (QBO 30 hPa) produces a particularly strong response at mid to polar latitudes, much stronger than the combined influence of sunspots and QBO, which was mostly studied in previous studies so far. This signal is robust and insensitive to the selected time period during the last century. Our results provide a useful way for improving the prediction of winter weather at middle to high latitudes of the northern hemisphere. [ABSTRACT FROM AUTHOR]

Abstract: The MEPED instruments onboard the low-altitude polar orbiting NOAA/POES satellites have measured energetic particles since 1978, offering a nearly continuous series of energetic particle fluxes in the magnetosphere during three solar cycles. However, there are several problems in using these data for long-term studies, the most significant one being that the solid state detectors of the MEPED proton instruments suffer significant radiation damage. This causes the effective energy thresholds of the instrument to increase, leading to underestimated particle fluxes already a couple of years after satellite launch. Before the MEPED data can reliably be used in any long-term study the data have to be recalibrated taking into account the decay of the detectors. In this paper we present quantified estimates of the degree of radiation damage for all NOAA/POES satellites, a method for correcting the MEPED proton measurements, and give an estimate of energetic proton fluxes from 1978 to present. [ABSTRACT FROM AUTHOR]

Highlights: [•] MT index can be used to estimate the contribution of magnetotail current to the Dst index. [•] WINDMI can successfully model the magnetotail contribution to the ground magnetic perturbation. [•] During substorms the intensity of the geomagnetic tail drops and is reflected in corresponding decrease in the MT index latitudes. [•] WINDMI model can reliably estimate the change in geotail current during substorms. [Copyright &y& Elsevier]

Abstract: We study the energetic electrons by the Cluster-II Rapid instrument on a dayside high-latitude pass on the night between March 21/22, 2001. The Cluster satellites were flying outward in the pre-noon sector, passing a cusp/cleft type region roughly at midnight. Contrary to earlier observations of high fluxes of energetic particles in the high-latitude cusp, we found a very low flux of energetic particles in this region. Soon thereafter the satellites entered the closed field line region of high-altitude magnetosphere with high fluxes of energetic particles and a low plasma density. While still in the region of downward oriented field lines, satellites observed surface waves propagating along magnetopause (MP) and modulating strongly the energetic particle fluxes. In the dayside sector satellites, observed several MP crossings, as well as periods when MP was quite stable and close to the satellites, even between them. We derive the speed and direction of the moving dayside magnetopause using observations of energetic electrons and plasma density. We also note that the moving magnetopause was often found to be connected with an increase of energetic electron flux while the stagnant MP was effectively a sink to energetic particles. [Copyright &y& Elsevier]

Abstract: We study the global properties of energetic (>30keV) particles during the main and early recovery phase of a major magnetic storm of March 31, 2001, using data of the NOAA 15 and 16 and the CLUSTER satellites. During the storm main phase the ring current energetic electron and ion fluxes were increased by nearly two orders of magnitude, and the flux maxima were shifted to below L =3. The maximum ion fluxes were observed at about 07UT, coinciding with the minimum Dst. However, the highest fluxes of energetic electrons were observed only at about 16–18UT, indicating significant differences in the acceleration of energetic electrons and ions during the storm. We suggest that the ion maximum at about 07UT was due to field-aligned acceleration of ions from the ionosphere whereas the electron maximum at 16–18UT was due to a large injection from the nightside. [Copyright &y& Elsevier]

Weekly monitoring of European all-cause excess mortality, the EuroMOMO network, observed high excess mortality during the influenza B/Yamagata dominated 2017/18 winter season, especially among elderly. We describe all-cause excess and influenza-attributable mortality during the season 2017/18 in Europe. Based on weekly reporting of mortality from 24 European countries or sub-national regions, representing 60% of the European population excluding the Russian and Turkish parts of Europe, we estimated age stratified all-cause excess morality using the EuroMOMO model. In addition, age stratified all-cause influenza-attributable mortality was estimated using the FluMOMO algorithm, incorporating influenza activity based on clinical and virological surveillance data, and adjusting for extreme temperatures. Excess mortality was mainly attributable to influenza activity from December 2017 to April 2018, but also due to exceptionally low temperatures in February-March 2018. The pattern and extent of mortality excess was similar to the previous A(H3N2) dominated seasons, 2014/15 and 2016/17. The 2017/18 overall all-cause influenza-attributable mortality was estimated to be 25.4 (95%CI 25.0-25.8) per 100,000 population; 118.2 (116.4-119.9) for persons aged 65. Extending to the European population this translates into over-all 152,000 deaths. The high mortality among elderly was unexpected in an influenza B dominated season, which commonly are considered to cause mild illness, mainly among children. Even though A(H3N2) also circulated in the 2017/18 season and may have contributed to the excess mortality among the elderly, the common perception of influenza B only having a modest impact on excess mortality in the older population may need to be reconsidered. [ABSTRACT FROM AUTHOR]

A correction to the article "Experience and Lessons From Surveillance and Studies of the 2009 Pandemic in Europe," by A. Nicoll et al. in a 2010 issue is presented.