Work

The Semidiurnal Tidal Response of the Low Latitude Ionosphere to Northern Hemisphere Polar Vortex Strength (2020–2023) From COSMIC‐2 Global Ionospheric Specification

Year: 2024

Type: article

Abstract: This paper investigates the day‐to‐day global tidal variability in the ionosphere/thermosphere system due to fluctuations in the strength of the northern hemisphere stratospheric polar vortex. Using COSMIC‐2 (Constellation Observing System for Meteorology, Ionosphere, and Climate‐2) Global Ionospheric Specification data, ionospheric tides are derived, with the Northern Annular Mode (NAM) index indicating polar vortex variability. The semidiurnal migrating solar tide shows the largest response, with relative electron density in the F‐region significantly higher ( 60%) under a weak vortex and lower ( 20%) under a strong vortex, correlated at −0.58 with the NAM index. The study compares solar/geomagnetic forcing and vortex impacts using SD‐WACCM‐X (Specified Dynamics Whole Atmosphere Community Climate Model with thermosphere and ionosphere extension) model runs. Findings suggest tidal modulation of the E‐region dynamo as the coupling mechanism. Our study can potentially improve ionospheric space weather predictability because the NAM index can be known a few days in advance.

Source: Geophysical Research Letters

DOI: 10.1029/2024gl111313

Authors: Deepali Aggarwal, Jens Oberheide, Nicholas Pedatella, Benjamin C. Martinez

Institutions: Clemson University, NSF National Center for Atmospheric Research, NSF NCAR High Altitude Observatory

Language: English

Topic: Ionosphere and magnetosphere dynamics

Subfield: Astronomy and Astrophysics

Field: Physics and Astronomy

Domain: Physical Sciences

SDG: Climate action

Open Access status: gold

Estimated APC paid: $2,900