Review of Environmental Monitoring by Means of Radio Waves in the Polar Regions: From Atmosphere to Geospace

The Antarctic and Arctic regions are Earth’s open windows to outer space. They provide
unique opportunities for investigating the troposphere–thermosphere–ionosphere–plasmasphere
system at high latitudes, which is not as well understood as the mid- and low-latitude
regions mainly due to the paucity of experimental observations. In addition, different
neutral and ionised atmospheric layers at high latitudes are much more variable compared
to lower latitudes, and their variability is due to mechanisms not yet fully understood. Fortunately,
in this new millennium the observing infrastructure in Antarctica and the Arctic
has been growing, thus providing scientists with new opportunities to advance our knowledge
on the polar atmosphere and geospace. This review shows that it is of paramount
importance to perform integrated, multi-disciplinary research, making use of long-term
multi-instrument observations combined with ad hoc measurement campaigns to improve
our capability of investigating atmospheric dynamics in the polar regions from the troposphere
up to the plasmasphere, as well as the coupling between atmospheric layers. Starting
from the state of the art of understanding the polar atmosphere, our survey outlines
the roadmap for enhancing scientific investigation of its physical mechanisms and dynamics
through the full exploitation of the available infrastructures for radio-based environmental
monitoring.