From solar flares to the Little Ice Age and the role of JSWSC

The Journal of Space Weather and Space Climate (JSWSC) was established as an open access journal at the end of 2010 and is celebrating a successful first decade. The journal has come a long way since its inception and there is much of which to be proud and to give confidence as JSWSC moves into its second decade as a champion of open science and an integral part of the European space weather community.

“The Journal of Space Weather and Space Climate was created by the space weather community and holds a special place at the heart of that community.”
– Anna Belehaki and Jean Lilensten (Editors-in-Chief).

10 years after the launch of the Journal of Space Weather and Space Climate, the Editors reflect on the birth and history of the journal…

JSWSC is an international Gold Open Access journal. It emerged from a European space weather community effort, but the Editorial Board was soon expanded to include experts also from other continents. It consists, currently, of 24 Associate Editors whose expertise covers all aspects of the discipline. It is published by EDP Sciences in an electronic online version only. It benefits from strong support by the Solar-Terrestrial Centre of Excellence (STCE) in Brussels, Belgium. The impact factor has been rising continuously, reaching a 2019 2-year IF of 3.095 and a 5-year IF of 2.981 (Clarivate Analytics JCR).

Why solar activity is a core subject in JSWSC

The Sun is at the origin of space weather events. Before impacting the Earth and exercising a benign or malign influence they propagate through the heliosphere, the magnetosphere, and the upper atmosphere. In order to understand and eventually predict origin and impact of space weather the whole chain from the Sun to the Earth must be considered with the help of observations, data analysis and modelling. Accurate modelling is particularly important for the heliosphere where direct observations are rare. JSWSC addresses all these spheres. We show below some examples, starting with solar activity.

“Solar flares, coronal mass ejections and solar energetic particle event characteristics” (A. Papaioannou et al., 2016) proposes a new catalogue of 314 solar energetic particle (SEP) events extending over a time span from 1984 to 2013. The properties as well as the associations of these SEP events with their parent solar sources are thoroughly examined and show that most of the SEP events do not conform to a simple two-class (impulsive or gradual) paradigm.

The link of the solar activity with the Earth climate constitutes an actively discussed topic in the literature to which JSWSC has contributed. “The Maunder minimum and the Little Ice Age: an update from recent reconstructions and climate simulations” (M. J. Owens et al., 2017) revisits the Maunder minimum - a period of extremely low solar activity from approximately AD 1650 to 1715. This period is sometimes associated with a period of cooler global temperatures, referred to as the Little Ice Age, and thus taken as compelling evidence of a large, direct solar influence on climate. The authors show that the timing of the features are not suggestive of causation and should not be used as evidence of significant solar forcing of climate. Their simulations suggest that multiple factors, particularly volcanic activity, were crucial for causing the cooler temperatures in the northern hemisphere during the Little Ice Age. A reduction in total solar irradiance likely contributed to the Little Ice Age at a level comparable to changing land use.

In order to complete the understanding of the chain from the Sun to the Earth (or other planets) much effort has been spent on modelling the evolution of events of solar activity in the solar corona and its subsequent propagation through the heliosphere. "EUHFORIA: European heliospheric forecasting information asset" (J. Pomoell & S. Poedts, 2018) describes a recently developed European forecasting-targeted two-component model consisting of a semi-empirical solar corona model and a three-dimensional time dependent MHD model of the heliosphere out to 2 AU. Initial tests targeting a highly dynamic heliosphere have rendered promising results. The model is shown to be able to capture the state of the heliosphere in good agreement with in-situ observations.

A substantial part of JSWSC articles address the impact of solar activity on the Earth's space environment, among it the ionosphere whose spatial and temporal plasma distribution significantly affects communication and navigation by means of radio waves. “Climatology characterization of equatorial plasma bubbles using GPS data” (S. Magdaleno, et al., 2017) studies the climatology of equatorial plasma bubbles for the period 1998–2008 using the total electron content derived from global positioning system data from stations distributed worldwide. It demonstrates that the largest occurrence rate of plasma bubbles takes place at the magnetic equator in the South America-Africa sector.

JSWSC also addresses planetary space weather. The success of Martian exploration projects – especially human ones - will in part depend on the ability to cope with the adverse effects of solar activity. That is the aim of “Modeling the effectiveness of shielding in the earth-moon-mars radiation environment using PREDICCS: five solar events in 2012” (P. R. Quinn, et al, 2017). The authors model how shielding mitigates the dose accumulated by astronauts and propose an online tool for the near real-time prediction of radiation exposure at Earth, the Moon, and Mars behind various levels of shielding.

“The success of Martian exploration projects – especially human ones - will in part depend on the ability to cope with the adverse effects of solar activity.”

Innovating for the future

In 2019, a supplement to the JSWSC, named ‘Agora’, was created. The Agora accommodates publications fundamentally different from regular research, technical, and review papers. It accommodates reports on Education and Public Outreach activities, historical observations, inventions, physical concepts, commentaries which outline ideas, research concepts, action plans (e.g., roadmaps) and meeting and project reports. The Agora articles are reviewed by at least four editors.

One of the most downloaded JSWSC articles belongs to the Agora. “Assessment and recommendations for a consolidated European approach to space weather – as part of a global space weather effort” (Opgenoorth et al., 2019) shows how Europe may coordinate Space Weather efforts in individual countries as well as in and among European organisations such as the European Space Agency and the European Union. It reviews many international activities worldwide and provides advice on how Europe could incorporate its future space weather activities into a global scheme.

Jean Lilensten, Anna Belehaki, Jürgen Watermann and Jan Janssens.