Browsing by Type "Controlled Vocabulary for Resource Type Genres::texto::revista::artículo"
  • Institution Publication
    Recent Deoxygenation of Patagonian Fjord Subsurface Waters Connected to the Peru–Chile Undercurrent and Equatorial Subsurface Water Variability
    (American Geophysical Union, 2023-05-26)
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    In recent decades, global dissolved oxygen (DO) measurements have registered a decrease of ∼1%–2% in oxygen content, raising concerns regarding the negative impacts of ocean deoxygenation on marine life and the greenhouse gas cycle. By combining in situ data from 2016 to 2022, satellite remote sensing, and outputs from a physical-biogeochemical model, we revealed the deoxygenation process in the Patagonian fjords for the first time. Deoxygenation was associated with the advection of equatorial subsurface water (ESSW) mass into the northern region of Patagonia. An analysis of the circulation regime using the Mercator-Ocean global high-resolution model confirmed the importance of the Peru–Chile undercurrent (PCUC) in transporting the ESSW poleward, contributing to the entrance of ESSW into the northern Patagonian fjords. A mooring system installed in the water interchange area between the Pacific Ocean and Patagonian fjords detected a decreasing DO of −21.66 μmol L⁻¹ over 7 years, which was explained by the increase in PCUC transport of 1.46 Sv. Inside the Puyuhuapi fjord system, a second DO time series exhibited more marked deoxygenation with −88.6 μmol L⁻¹ over 3 years linked with the influence of ESSW and local processes, such as DO consumption by the organic matter degradation. The recent deoxygenation registered in the northern Patagonian fjords demonstrates the significance of studying DO in the context of reducing the global oxygen content, further warranting the quantification of the impacts of deoxygenation on life cycles of marine organisms that inhabit the Patagonian fjords and channels and the Humboldt current system.
  • Institution Publication
    Topside Equatorial Ionospheric Plasma Density, Temperature, Composition, and Drifts Measurements at Jicamarca Under June Solstice, Moderate Solar Flux Conditions
    (John Wiley and Sons, 2026-02-05)
    Scipión Castillo, Danny Eddy
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    HYSELL, D.L.
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    VARNEY, R.H
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    KUYENG, KARIM
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    HUBA, J.D.
    State parameter profiles in the equatorial topside ionosphere were measured in June, 2023, and late July and early August, 2025, at the Jicamarca Radio Observatory. The measurements combined multiple radar pulsing schemes and analysis methods. In 2025, for the first time, plasma drifts were measured concurrently with electron densities, electron and ion temperatures, and ion composition by exploiting a new electronic beam steering capability. Significant quiet-time day-to-day variability is evident across all measurements. In this study, variability in the vertical drifts is considered as a source of variability in the other plasma state parameters. Topside temperatures and the midday temperature depression in particular are examined for sensitivity to vertical drifts. While predictions obtained from the SAMI2-PE model, which includes energetic electron transport, exhibit reasonable agreement with observations overall, they do not account for topside variability. Some limitations of the measurements and the model along with strategies for improvement and further study are discussed.