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Abstract The occurrence of plasma irregularities and ionospheric scintillation over the Caribbean region have been reported in previous studies, but a better understanding of the source and conditions leading to these events is still needed. In December 2021, three ground-based ionospheric scintillation and Total Electron Content monitors were installed at different locations over Puerto Rico to better understand the occurrence of ionospheric irregularities in the region and to quantify their impact on transionospheric signals. Here, the findings for an event that occurred on March 13–14, 2022 are reported. The measurements made by the ground-based instrumentation indicated that ionospheric irregularities and scintillation originated at low latitudes and propagated, subsequently, to mid-latitudes. Imaging of the ionospheric F-region over a wide range of latitudes provided by the GOLD mission confirmed, unequivocally, that the observed irregularities and the scintillation were indeed caused by extreme equatorial plasma bubbles, that is, bubbles that reach abnormally high apex heights. The joint ground- and space-based observations show that plasma bubbles reached apex heights exceeding 2600 km and magnetic dip latitudes beyond 28 ° . In addition to the identification of extreme plasma bubbles as the source of the ionospheric perturbations over low-to-mid latitudes, GOLD observations also provided experimental evidence of the background ionospheric conditions leading to the abnormally high rise of the plasma bubbles and to severe L-band scintillation. These conditions are in good agreement with the theoretical hypothesis previously proposed. Graphical Abstract
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GOLD plasma bubble observations comparison with geolocation of plasma irregularities by back propagation of the high-rate FORMOSA7/COSMIC 2 scintillation data
Using the high-rate phase and amplitude scintillation data from FORMOSA7/COSMIC two mission and back-propagation method, we geolocate plasma irregularities that cause scintillations. The results of geolocation are compared with the NASA GOLD UV image data of plasma bubbles. The root mean square of the zonal difference between estimated locations of plasma irregularities and plasma bubbles are about 1.5° and for single intersection cases 0.5° in the magnetic longitude. The geolocation data provide more accurate scintillation location around the globe compared to assigning to the tangent point and is valuable space weather product, which will be routinely available for public use.
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- Award ID(s):
- 2054356
- PAR ID:
- 10517988
- Publisher / Repository:
- Frontiers
- Date Published:
- Journal Name:
- Frontiers in Astronomy and Space Sciences
- Volume:
- 11
- ISSN:
- 2296-987X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3389/fspas.2024.1407457
