Conveners
T4-6 DASP General Contributions I (DASP) | DPAE: contributions générales I (DPAE)
- Johnathan Burchill (University of Calgary)
Nearly 300 years have passed since the watchmaker
G. Graham constructed a more sensitive compass and showed
that the variations in geomagnetic direction varied with an
irregular daily pattern.
More recently, but still 75 years ago, Loeve showed
that a proper description of such nonstationary
processes required at least two time or frequency variables.
Forty years of experience studying...
Two recent discoveries from the Canadian ACE-FTS (Atmospheric Chemistry Experiment – Fourier Transfer Spectrometer) satellite instrument will be discussed. The first is the production of N2O in the lower thermosphere, and the second is a global enhancement of HCN in the upper troposphere – lower stratosphere throughout 2016. ACE-FTS has the only available satellite measurements of...
Radio waves propagating through plasma in the Earth's ambient magnetic field experience Faraday rotation; the plane of a linearly polarized wave changes as a function of the distance travelled through a plasma. Linearly polarized radio waves at 1090 MHz frequency are emitted by ADS-B devices which are installed on most commercial aircraft. These radio waves can be detected by satellites in ...
All optically detectable meteors, as well as many of the strong radio-detectable meteors, produce shockwaves prior to their terminal stage in the MLT (Mesosphere-Lower Thermosphere) region of the atmosphere, at altitudes between 75 km and 100 km. The strengths of the meteor-generated shock waves depend on meteor atmospheric velocities and the values of the relevant Knudsen number. However,...
E region irregularities have been probed for decades through various frequency radars as well as rockets. Even though the maximum growth rate of the instability responsible for the development of the underlying structures should have produced magnetic field aligned irregularities moving at the electron ExB drift, they have been found instead to often move at the ion-acoustic speed times the...
