Long time series reveal Arctic change

The Sodankylä Geophysical Observatory is part of the University of Oulu, bringing academic research and its own magnetic charm to this part of the Arctic. Sodankylä was not chosen as the observatory site by chance. The area north of the Arctic Circle is known for its Northern Lights, which are visible on average every second night. Monitoring the Earth’s magnetic field has provided research data for the scientific community since 1913.

"Large solar flares produce a magnetic cloud that creates not only beautiful patterns in the sky, but also problems. Even before hitting the Earth, the outburst affects satellites. These get broken, and a lot of useful information is lost. For example, GPS positioning may be disrupted or interrupted. Such eruptions also affect nature, where their traces are visible over long time series," says Jyrki Manninen, Vice Director of the Sodankylä Geophysical Observatory. Monitoring and time series help to anticipate future eruptions and thus avoid some of the problems.

In addition to his main job, Manninen is also a member of the Advisory Group of the Arctic Interactions (ARCI) programme. The group includes members from a wide range of disciplines and many organisations active in the Arctic.

At the moment, the climate is clearly changing and warming – and has been for some time. There are many warmer and colder periods in history. According to Manninen, the long time series also show that not all warming has always been caused by human activity.

"The Kilpisjärvi Biological Station has time series data from the 1700s onwards. This data shows that there have been several warm periods in recent centuries. The Natural Resources Institute Finland (LUKE) has annual tree growth data suggesting a warmer period like the present one in the 500-600s. At that time, the warming is unlikely to have been caused by human activity. An eruption larger than the eruption of the Pinatubo volcano and the resulting widespread atmospheric ash could be one explanation for the relatively rapid cooling that followed that warming," says Manninen, who is familiar with the time series of annual tree growth.

"From a geophysics point of view, the 110-year history of our observatory is not yet a cause for much celebration, although it is a long time compared to a human lifetime. But it’s a good start for long time series."

Originally from Ylä-Savo, Manninen has lived in Sodankylä for decades. In addition to his work as a researcher, he has also worked as the Director of Economic Development of the municipality of Sodankylä. Thus, in addition to his long time series, Manninen also has insights into the recent history of the Arctic region.

"Sodankylä is definitely part of the Arctic region and so we have the same challenges and opportunities here as elsewhere. The research community that has grown up around the observatory is important for the whole region. The cooperation agreement between the municipality and the University of Oulu enables us to do many things. There is a lot of ore exploration, as well as traditional reindeer husbandry. The diverse economic structure is a strength," Manninen lists.

Established under the Tsarist rule, the observatory has traditionally had a long history of collaboration with geophysics researchers in both the Soviet Union and Russia. Now, due to Russia’s war of aggression, all cooperation is completely broken and the future is unknown. Cooperation projects with the EU, Japan and the US research communities have become even more important.

According to Manninen, the ARCI advisory group has been a great example of the usefulness of interdisciplinary cooperation. There could have been more meetings, but they had to be cancelled due to the pandemic. In concrete terms, cooperation with ARCI has also been reflected in researcher visits with Nagoya University.

"It's easy to become blind to your own issues and perspectives, so a multidisciplinary advisory group provides a whole new way of thinking. As a representative of the hard sciences, I have gained a lot from the other members of the group and hopefully also been able to bring new insights to the group's discussions," says Manninen.

"Earth always reaches some kind of equilibrium sooner or later. The Arctic is a significant part of the planet, and therefore important to the whole. The future of our humanity is another matter entirely: how well will it cope with the various changes and upheavals of the future?"

The future will be revealed to us in time, by time series: as long as someone is constantly recording and analysing the results of research.