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Showing 1 to 20 of 194 for “"High Latitude"”.
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High-Latitude Ionospheric Irregularities Characterized Through Machine Learning Methods
… to understand plasma irregularities in high-latitude regions better. By combining observations and recent findings from modeling, the goal is to identify and classify scintillation signatures caused by different types of irregularities in the ionosphere. The focus is on irregularities …
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High-Latitude Southern Hemisphere Climate Variability, Trends, and Tropical Forcing.
… variability in the Southern Hemisphere (SH) high-latitudes, with a focus on the time-varying behaviour and long-term trends in Antarctic sea ice and atmospheric circulation, as diagnosed from observations, reanalyses, and simulations using an Atmospheric General Circulation Model (AGCM). …
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The role of high-latitude oceans in transient climate change
… then advected northward and subducted in the mid-latitudes. This geographical imprint of the MOC is reflected in the regional CRFs to GHGs, as seen in idealized numerical experiments with GCMs. However, GHGs are not the only major source of anthropogenic forcing on the SO. Stratospheric ozone …
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Investigation of High Latitude Ionospheric Irregularities utilizing Modeling and GPS Observations
… coupling mechanisms result in high latitude irregularities that are difficult to characterize. Until recently, the polar and auroral irregularities remained largely unexplored. Inadequate infrastructures to deploy and maintain advanced dual frequency Global Navigation Satellite …
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High-latitude electron density observations from the IMAGE radio plasma imager
… the IMAGE mission, electron densities in the high latitude, high altitude region of the magnetosphere were measured exclusively by in situ means. The Radio Plasma Imager instrument onboard IMAGE is capable of remotely observing electron densities between 0.01 and 100,000 e-/cm-3 from distances …
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Transport and energization of heavy ions in earth’s high latitude ionosphere
Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2024-03-01 without embargo terms
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High-latitude sedimentation in response to climate variability during the Cenozoic
Here we investigate sedimentological responses to past climate change in shallow to deep marine depositional environments. Our primary study spans from the Late Pliocene to the Pleistocene (3.3 to 0.7 Ma), and features results from two International Ocean Discovery Program (IODP) Sites U1525 and …
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Influence of high latitude anomalies on tropical climate phenomena and global climate
The tropical ocean and atmosphere are a highly active and very important region of the globe. Climate phenomena such as El Ni˜no (Philander, 1990), the Tropical Atlantic Dipole, and the Indian Ocean Dipole, play an important role in global climate variability. The tropical atmospheric boundary …
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Impacts of Anisotropy, Wave Heating, and Neutral Winds on High-Latitude Ionospheric Dynamics
… of ionospheric plasma can be transported to high altitudes (ion upflow) in response to a variety of plasma heating and uplifting processes such as DC electric fields and precipitation. Once ions have been lifted to high altitudes, transverse ion acceleration by broadband ELF waves can give the …
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The Vulnerability of Northern High-Latitude Ecosystems to Climate and Disturbance-Induced Change
… Administration) and techniques and results are highly relevant to climatic, hydrologic, ecologic, topographic, and cryospheric studies. This research provides critically needed information on the temporal and regional distribution of landscape properties and conditions, which is instrumental in …
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High resolution palaeoceanography and palaeoclimatology from mid and high latitude Late Cretaceous laminated sediments
… flux may indicate that the ~43°N palaeolatitude estimate is incorrect, and deposition actually occurred at lower latitudes or alternatively, that the Marca basin was influenced by intense monsoonal summer storms. The CESAR 6 annual flux cycle consists of alternating diatom resting spore …
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Coccolithophores in high latitude and Polar regions: Relationships between community composition, calcification and environmental factors
… huxleyi B/C. Diversity and abundance were highest in the Subantarctic and Polar Frontal Zones, respectively, where temperature and mixed layer irradiance were high. Community and cell specific calcification, as well as coccolith production rates, showed an overall decreasing trend towards …
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Particle export and flux through the Mesopelagic in the high-latitude north and South Atlantic
… acid waters of the South Atlantic with very high copepod grazing pressure only caused a modest phytoplankton response and no enhancement of downward particle flux. This was probably primarily due to grazing control and detritus-feeding by copepods, since diatom growth rates were apparently …
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Spectral studies of small-scale auroral structure and plasma instability in the high-latitude ionosphere
… been observed by incoherent-scatter radars at high-latitudes. It has been proposed that these radar enhancements result from natural plasma instability, causing the generation of ion-acoustic waves through the decay of unstable Langmuir waves, themselves driven by low-energy electron streams. …
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F-region Dusk Ion Temperature Spikes at the Equatorward Edge of the High Latitude Convection Region
… the radar was on the equatorward edge of the high latitude convection region. These enhancements were several hundred Kelvin above the background temperature, would last less than 15 minutes and were preceded by sharp depletions in plasma density (of roughly one half). Though they were mostly …
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High-latitude coupling processes between thermospheric circulation and solar wind driven magnetospheric currents and plasma convection
The high-latitudinal thermospheric processes driven by the solar wind and Interplanetary Magnetic Field (IMF) interaction with the Earth magnetosphere are highly variable parts of the complex dynamic plasma environment, which represent the coupled Magnetosphere – Ionosphere – Thermosphere (MIT) …
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A new snowfall detection algorithm for high latitude regions based on a combination of active and passive sensors
Precipitation retrieval over high latitudes, particularly snowfall retrieval over ice and snow, using satellite-based passive microwave spectrometers, is currently an unsolved problem. The challenge results from the large variability of microwave emissivity spectra for snow and ice surfaces, which …
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