Blar i NTNU Open på forfatter "Espy, Patrick Joseph"
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Optimizing an Infrared Camera for Observing Atmospheric Gravity Waves from a CubeSat Platform
Rønning, Snorre Stavik (Master thesis, 2012)The NTNU Test Satellite (NUTS) is a double CubeSat deigned by master students at NTNU. The goal of the project is to image atmospheric gravity waves in the OH airglow layer. This thesis explores the theory behind gravity ... -
Optimizing hydroxyl airglow retrievals from long-slit astronomical spectroscopic observations
Franzen, Christoph; Hibbins, Robert; Espy, Patrick Joseph; Djupvik, Anlaug Amanda (Journal article; Peer reviewed, 2017)Astronomical spectroscopic observations from ground-based telescopes contain background emission lines from the terrestrial atmosphere's airglow. In the near infrared, this background is composed mainly of emission from ... -
Påvirkningen av temperaturgradienter for tolkningen av rotasjonstemperaturer
Borge, Halvor (Master thesis, 2018)Hydroksyl (OH) utstråling er en fotokjemisk reaksjon som skjer i et relativt tynt område ($\sim$5 km) sentrert rundt ca 90 km høyde. I denne oppgaven ble det laget et syntetisk spektrum ved hjelp av en steady-state kjemimodell ... -
Permeability, Growth and Morphology of Coastal Ice - Site Study in Van Mijenfjorden, Svalbard
Blæsterdalen, Bård (Master thesis, 2015)Coastal ice includes the parts of the sea ice that are stressed and deformed by tidal motion; the ice foot (the inner part that is frozen to the ground) and the hinge zone (the zone where cracking occurs due to tidal ... -
Planetary Wave Oscillations observed in Ozone and Temperature Data from Antarctica during 2009
Osnes, Christine Birgitte (Master thesis, 2011)Ozone and temperature data from Troll and Rothera research stations has been analyzed in order to trace planetary waves. Seasonal variations were removed and spectral analysis was performed in order to find dominating ... -
Planetary Waves over Antarctica
Andresen, Sigurd Nord (Master thesis, 2022)Denne oppgaven undersøker hypotesen lagt frem av Alan Plumb i 1989 med formålet om å forklare nedkjølingen midtvinter i mesosfæren over Antarktis. Fundamentet til denne hypotesen bygger på at de planetarisk bølgene ikke ... -
Probing Gravity Waves in the Middle Atmosphere Using Infrasound From Explosions
Vorobeva, Ekaterina; Assink, Jelle; Espy, Patrick Joseph; Renkwitz, Toralf; Chunchuzov, Igor; Näsholm, Sven Peter (Peer reviewed; Journal article, 2023)This study uses low-frequency, inaudible acoustic waves (infrasound) to probe wind and temperature fluctuations associated with breaking gravity waves (GWs) in the middle atmosphere. Building on an approach introduced by ... -
Quasi-16-day period oscillations observed in middle atmospheric ozone and temperature in Antarctica
Demissie, Teferi Dejene; Kleinknecht, Nora; Hibbins, Robert; Espy, Patrick Joseph; Straub, Corinne (Journal article; Peer reviewed, 2013)Nightly averaged mesospheric temperature derived from the hydroxyl nightglow at Rothera station (67°34' S, 68°08' W) and nightly midnight measurements of ozone mixing ratio obtained from Troll station (72°01' S, 2°32' E) ... -
Satellite mapping of particle precipitation effects on the Antarctic middle atmosphere
Lisa, Martin (Master thesis, 2011)The aim of this thesis is to study the effects of particle precipitation on O3 and OH caused by a moderate geomagnetic storm in late July 2009. The basis is data retrieved over Antarctica from the Odin and Aura satellites ... -
Solar Forcing of Planetary Waves
Slapgaard, Jon Kristian (Master thesis, 2021)Forskjellen i oppvarming på grunn av ozon mellom sommer- og vinterhalvkulene påvirker både direkte og indirekte vindfeltene i mesosfæren. Denne oppgaven skal undersøke om planetære bølger, som er sensitive til vindene de ... -
SuperDARN Observations of Semidiurnal Tidal Variability in the MLT and the Response to Sudden Stratospheric Warming Events
Hibbins, Robert; Espy, Patrick Joseph; Orsolini, Yvan; Limpasuvan, Varavut; Barnes, R. J. (Journal article; Peer reviewed, 2019)Using meteor wind data from the Super Dual Auroral Radar Network (SuperDARN) in the Northern Hemisphere, we (1) demonstrate that the migrating (Sun‐synchronous) tides can be separated from the nonmigrating components in ... -
The climatology of zonal wave numbers 1 and 2 planetary wave structure in the MLT using a chain of Northern Hemisphere SuperDARN radars
Kleinknecht, Nora; Espy, Patrick Joseph; Hibbins, Robert (Journal article; Peer reviewed, 2014)The zonal wave components 1 and 2 were extracted from the meridional wind along the latitude band of 51–66°N for the years 2000–2008 using eight Super Dual Auroral Radar Network (SuperDARN) radars spanning longitudes from ... -
The detection of Meteoric Smoke Particles with rocketborne sensors: A feasibility study
Balfour, Robert Nicolai William (Master thesis, 2020)Det overordnede målet med denne masteroppgaven er å undersøke gjennomførbarheten av å sende en sensor ombord en rakett for å detektere meteoriske røykpartikler i mesosfæren, for å kunne fastslå deres sammensetning. Denne ... -
The impact of energetic electron precipitation on mesospheric hydroxyl during a year of solar minimum
Sandanger, M.I.; Tyssøy, Hilde Nesse; Hibbins, Robert Edward; Zawedde, A.E.; Stadsnes, Johan; Espy, Patrick Joseph; Ødegaard, L-K (Journal article; Peer reviewed, 2016)In 2008 a sequence of geomagnetic storms occurred triggered by high-speed solar wind streams from coronal holes. Improved estimates of precipitating fluxes of energetic electrons are derived from measurements on board the ... -
The role of the QBO in the inter-hemispheric coupling of summer mesospheric temperatures
Espy, Patrick Joseph; Ochoa, Sara; Forkman, Peter; Murtagh, Donal; Stegman, Jacek (Journal article; Peer reviewed, 2010)Inter-hemispheric coupling between the polar summer mesosphere and planetary-wave activity in the extra-tropical winter stratosphere has recently been inferred using Polar Mesospheric Cloud (PMC) properties as a proxy for ... -
The role of the QBO in the inter-hemispheric coupling of summer mesospheric temperatures
Espy, Patrick Joseph; Ochoa, Sara; Forkman, P; Murtagh, D; Stegman, J. (Journal article; Peer reviewed, 2011)Inter-hemispheric coupling between the polar summer mesosphere and planetary-wave activity in the extratropical winter stratosphere has recently been inferred using Polar Mesospheric Cloud (PMC) properties as a proxy for ... -
The secondary ozone layer and energetic particle precipitation
Murberg, Lise Eder (Master thesis, 2022)Det sekundære ozonlaget er det globale toppunktet av ozon i øvre mesosfære-nedre termosfære (UMLT) rundt 90-100 km. Ved denne høyden fotodissosieres ozon lett på dagtid, noe som gjør at blandingsforholdet av ozon er større ... -
The SPARC water vapour assessment II: Comparison of annual, semi-annual and quasi-biennial variations in stratospheric and lower mesospheric water vapour observed from satellites
Lossow, Stefan; Khosrawi, Farahnaz; Nedoluha, Gerald E; Azam, Faiza; Bramstedt, Klaus; Burrows, John P.; Dinelli, Bianca M; Eriksson, Patrick; Espy, Patrick Joseph; Garcia-Comas, Maya; Gille, John C; Kiefer, Michael; Noel, Stefan; Raspollini, Piera; Read, William G.; Rosenlof, Karen H; Rozanov, Aleksej; Sioris, Christopher E; Stiller, Gabriele P; Walker, Kaley A.; Weigel, Katja (Journal article; Peer reviewed, 2017)In the framework of the second SPARC (Stratosphere-troposphere Processes And their Role in Climate) water vapour assessment (WAVAS-II), the amplitudes and phases of the annual, semi-annual and quasi-biennial variation in ... -
Transporterer atmosfæriske bølger polarlysprodusert NO ned til den midtre atmosfæren
Amundsen, Andreas (Master thesis, 2016)Hensikten med denne studien var å undersøke potensielle mekanismer bak observerte nivåer av NO-gass i mesosfæren på høyder mellom 60 og 80 kilometer. Tre hypoteser ble formulert og undersøkt i denne sammenheng. Lokal ... -
Traveling planetary wave activity from mesopause region airglow temperatures determined by the Network for the Detection of Mesospheric Change (NDMC)
Reisin, Esteban R.; Scheer, Jürgen; Dyrland, Margit Elisabet; Sigernes, Fred; Deehr, Charles Sterling; Schmidt, Carsten H.; Höppner, Kathrin; Bittner, Michael; Ammosov, Petr P.; Gavrilyeva, Galina A.; Stegman, Jacek; Perminov, Vladimir I.; Semenov, Anatoly I.; Knieling, Peter; Koppmann, Ralf; Shiokawa, Kazuo; Lowe, Robert P.; López-González, Maria J.; Rodriguez, Eloy; Zhao, Yucheng; Taylor, Michael John; Buriti, Ricardo Arlen; Espy, Patrick Joseph; French, W. John R.; Eichmann, Kai Uwe; Burrows, John Philip; von Savigny, Christian H.P. (Journal article; Peer reviewed, 2014)The global distribution of traveling planetary wave (PW) activity in the mesopause region is estimated for the first time from ground-based airglow measurements. Monthly and total mean climatologies of PW power are determined ...