edu.ucar.opensky::articles:43841 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T17:48:19.067451 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.net/ark:/85065/d7v12989 https://doi.org/10.17592/002.2025010407 https Related Dataset #1 JAGUAR Data Assimilation System Whole neutral Atmosphere Reanalysis (JAWARA) https://doi.org/10.5880/Hpo.0003 https Related Dataset #2 Geomagnetic Hpo index (V3.0) https://doi.org/10.5281/zenodo.10000479 https Related Software #1 MATLAB and Python software to compute Fourier-wavelet spectra (fourierwavelet v1.2) using longitude-time data for studying global-scale atmospheric waves 2‐day ionospheric oscillations at low latitudes due to an ultra‐fast Kelvin wave 2025-06-01T00:00:00Z publication https://n2t.net/ark:/85065/d7v12989 https://doi.org/10.1029/2025EA004322 Jadhav, A. P. author Yamazaki, Y. author Gurubaran, S. author Sato, K. author Koshin, Dai author UCAR/NCAR - Library publisher This study establishes an observational connection between an ultra&#8208;fast Kelvin wave (UFKW) and the occurrence of counter electrojet (CEJ) in the equatorial E region and planetary wave&#8208;like oscillations in low&#8208;latitude total electron content (TEC), based on a case study of CEJ events that occurred in December 2017. During this period, noontime CEJ was observed by ground&#8208;based magnetometers with a periodicity of &#8764;2&#160;days. The analysis of hourly wind data from the JAGUAR&#8208;DAS Whole neutral Atmosphere Reanalysis reveals the presence of an eastward&#8208;propagating UFKW with a zonal wavenumber of 1 (E1) and a period of &#8764;2&#160;days along with an enhancement of eastward wind in the equatorial dynamo region which coincided with occurrence of CEJ. Observations from the Swarm satellite mission confirm the presence of equatorial electrojet (EEJ) oscillations associated with the UFKW. This is the first time that an UFKW has been identified as a source of day&#8208;to&#8208;day variability in CEJ. As CEJ is linked to a reduced daytime upward plasma drift over the magnetic equator, TEC at low latitudes also varies at a period of &#8764;2&#160;days. The analysis of global TEC maps reveals that the 2&#8208;day TEC variations consist not only of the eastward propagating wavenumber 1 component but also of the westward propagating wavenumber 2 (W2) component. The latter arises from the interaction of the E1 UFKW with the diurnally varying ionosphere. The 2&#8208;day TEC variations exhibit significant longitudinal dependence due to the interplay of constructive and destructive interferences between the E1 and W2 2&#8208;day oscillations. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication <span style="font-family:Arial;font-size:10pt;font-style:normal;" data-sheets-root="1">Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</span> None eng geoscientificInformation