Observing and Modeling the Sun-Earth System

H.-L. Liu, W. Wang, J. D. Huba, P. H. Lauritzen, and F. Vitt analyze the Hunga Tonga-Hunga Ha'apai Volcano waves that have been recorded by ground and satellite instrumentation. This event provides a rare opportunity to study the strong and direct connection of the whole atmosphere system. The high-resolution Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension (WACCM-X) can simulate the global propagation of the waves, and the model results compare favorably with observations from the surface to the thermosphere and ionosphere.

Kevin Pham et al. utilize numerical modeling to investigate ring current buildup for a specific solar storm, and find that flows that are medium scale relative to the system size and referred to as plasma “bubbles”, are responsible for at least half of the total buildup of ring current plasma. Our analysis also shows that the bubbles displace some of the background plasma on their way Earthward, which is important when calculating their net contribution to the ring current.

JGR-Space:  Liying Qian, Wandi Yu, Nicholas Pedatella, Jia Yue, Wenbin Wang examine hemispheric asymmetry of the annual and semiannual variation of the ratio of O and N2 concentrations (O/N2) using observations by the GUVI instrument onboard the TIMED satellite and compare them with WACCM-X model simulations. They observe and compare the equatorial region (“equinox peaks”) in varying months and hemispheres.