Related Experiment Video
Updated: Jul 12, 2026

Removal of Exogenous Materials from the Outer Portion of Frozen Cores to Investigate the Ancient Biological Communities Harbored Inside
Published on: July 3, 2016
Stratospheric meteorological conditions in the arctic polar vortex, 1991 to 1992
Abstract:
Stratospheric meteorological conditions during the Airborne Arctic Stratospheric Expedition II (AASE II) presented excellent observational opportunities from Bangor, Maine, because the polar vortex was located over southeastern Canada for significant periods during the 1991-1992 winter. Temperature analyses showed that nitric acid trihydrates (NAT temperatures below 195 k) should have formed over small regions in early December. The temperatures in the polar vortex warmed beyond NAT temperatures by late January (earlier than normal). Perturbed chemistry was found to be associated with these cold temperatures.
Related Concept Videos
Global Climate Change
What is Climate?
What is Weather?
Magnetostatic Boundary Conditions
Phase Transitions: Vaporization and Condensation
Phase Transitions: Sublimation and Deposition

