Birkelandforelesningen

Professor Ryoichi Fujii fra Solar-Terrestrial Environment Laboratory ved Nagoya University i Japan holder årets Birkelandforelesning.

Tittelen på hans foredrag er: "Long-lasting Norway-Japan collaboration in solar-terrestrial science".

Sammendrag på engelsk:

Scientific exchange between Norway and Japan started in the beginning of the 20th century. Around that time a genius physicist, Professor Kristian Birkeland, visited his colleagues at the University of Tokyo, Japan, where he died unanticipated in 1917.

Since the 1970s, Norway-Japan collaboration in solar-terrestrial science has been enhanced through ground-based and rocket-borne auroral observations in mainland Norway and Svalbard. The ionosphere/thermosphere is the outermost portion of the Earth's atmosphere and partially ionized. Connected to the fully ionized magnetosphere through magnetic field lines is the polar ionosphere, where several spectacular physical phenomena including auroras, appear.

Currents flowing along the magnetic field lines play a key role in the magnetosphere-ionosphere coupling. They were first proposed by Birkeland, more than 60 years before they were first observed with satellites in the 1960s.

In addition to being the basis of fundamental auroral plasma physics, the research of the ionosphere-thermosphere-magnetosphere coupling is important for understanding environmental issues such as global warming and space weather.

The European Incoherent Scatter (EISCAT) radar system in northern Scandinavia has been a central tool to investigate the polar upper atmosphere. EISCAT consists of very powerful incoherent scatter radars with supplemental ionospheric heating facilities.  EISCAT has been getting more comprehensive with complementary state-of-the art equipments, such as the recent Japanese installation of a sodium lidar at Tromsø. Furthermore, EISCAT plans to construct a new three-dimensional imaging radar, called EISCAT-3D, to make spatially and temporarily continuous measurements of the geospace environment and its coupling to the Earth's atmosphere. This new facility will certainly be the most powerful incoherent scatter radar for polar upper atmospheric and space research in the world, and will contribute to innovative progress in solar-terrestrial science.