•CEDAR Frontiers: Utilizing Global Models to
Better Understand the Ionosphere and
Aaron Ridley - University of Michigan - firstname.lastname@example.org
● Idealized Events
Measurements are limited by what the system is driven by,
where models can be driven by ideal conditions - can
conduct numerical experiments.
Impulse - Response functions allow a better understanding of
how the system responds to zeroeth order.
Idealized events are similar to “averaged” events.
o Put data into a global context, can provide
“measurements” that were not made.
o Provide validation studies for global models - What
physics is missing? What don’t we understand?
Propose studies that advance;
Understanding of the global coupled ionosphere and
Understanding of the strengths and limitations of global models.
Understanding of how experimentalist and modellers can work
together to better understand the system.
Utilizing Global Models to Better Understand
the Ionosphere and Thermosphere
The Sun never produces idealized conditions at times in which instruments are placed in
optimum locations to observe what experimentalists want to measure. Also, researchers have a
difficult time measuring all relevant processes simultaneously to determine cause and effect.
Models offer the ability to drive the system over and over again with idealized conditions. Slight
variations on those conditions can be made to systematically test theories in a highly controlled
environment. Models also offer the ability to change the way “the world works” to better
determine cause and effect. Model runs of idealized conditions can be compared against super-
posed epoch average conditions to determine if the model is behaving like the true system.
Models help to put experimental data into a global context - they can specify conditions far away
from the measurements and can provide quantities that were not measured. The coupling
between models and experimental results can give a better context for considering theories than
simply models or localized measurements.
Validation studies provide an opportunity for improving our understanding of the global system
by forcing researchers to examine the underlying physics of the models. This typically results in
both a better physical understanding of the thermosphere and ionosphere and improvements in
Possible CEDAR Campaign
o Providing a framework for experimentalists to better understand modelling
and modellers to better understand the benefits of measurements.
o Conducting idealized event studies agreed upon by modellers and
experimentalists to better understand outstanding questions in CEDAR
o Supporting the CEDAR community by modelling events of high interest in a
more uniform environment.
o Providing a forum for modellers to compare results for a more informed
discussion on the numerical and physical differences between models.
o Stressing the importance of validated models in CEDAR.
o Increase collaboration between experimentalists and modellers.
o Increase our understanding of the differences between community models.
o Create more transparency and uniformity in the validation of models.
o Provide community support for event studies.
CEDAR Frontiers- Utilizing Global Models to Better Understand the
Ionosphere and Thermosphere