Zobrazeno 1 - 10
of 153
pro vyhledávání: '"N. Partamies"'
Publikováno v:
Annales Geophysicae, Vol 42, Pp 355-369 (2024)
Auroral electron precipitation during a substorm exhibits complex spatiotemporal variations which are still not fully understood, especially during the very dynamic phase immediately following the onset. Since during disturbed times, the auroral oval
Externí odkaz:
https://doaj.org/article/09c5b577794b4beeac580f55d8028823
Publikováno v:
Annales Geophysicae, Vol 42, Pp 103-115 (2024)
Due to a large number of automatic auroral camera systems on the ground, image data analysis requires more efficiency than what human expert visual inspection can provide. Furthermore, there is no solid consensus on how many different types or shapes
Externí odkaz:
https://doaj.org/article/0377e16bc9f34ee99dc2adedd8d366bb
Publikováno v:
Annales Geophysicae, Vol 41, Pp 483-510 (2023)
Substorms are a commonly occurring but insufficiently understood form of dynamics in the coupled magnetosphere–ionosphere system, associated with space weather disturbances and auroras. We have used principal component analysis (PCA) to characteriz
Externí odkaz:
https://doaj.org/article/e66a67ad3c7444b18d397888b6305027
Publikováno v:
Annales Geophysicae, Vol 41, Pp 115-128 (2023)
We investigated the morphology of poleward moving auroral forms (PMAFs) qualitatively by visual inspection of all-sky camera (ASC) images and quantitatively using the arciness index. The PMAFs in this study were initially identified with a meridian s
Externí odkaz:
https://doaj.org/article/dcc7ba3f3382470187d1133d40431fac
Publikováno v:
Annales Geophysicae, Vol 41, Pp 1-12 (2023)
We have performed a large statistical study of the peak emission altitude of green O(1D2–1S0) (557.7 nm) and blue N2+ 1 N (427.8 nm) aurora using observations from a network of all-sky cameras stationed across northern Finland and Sweden recorded d
Externí odkaz:
https://doaj.org/article/d5feb485730642ac88199ee27dba9bd3
Publikováno v:
Annales Geophysicae, Vol 40, Pp 605-618 (2022)
We investigate the bulk behaviour of auroral structures and peak emission height as a function of magnetic local time (MLT). These data are collected from the Fennoscandian Lapland and Svalbard latitudes from seven identical auroral all-sky cameras (
Externí odkaz:
https://doaj.org/article/54e07ef4afbe4dbf8bab7827ed21ea4a
Publikováno v:
Annales Geophysicae, Vol 40, Pp 1-10 (2022)
Energetic particle precipitation associated with pulsating aurora (PsA) can reach down to lower mesospheric altitudes and deplete ozone. It is well documented that pulsating aurora is a common phenomenon during substorm recovery phases. This indicate
Externí odkaz:
https://doaj.org/article/411e19ed2a3d4c11bdfd4de87941e2b9
Publikováno v:
Geoscientific Instrumentation, Methods and Data Systems, Vol 11, Pp 25-35 (2022)
Radio wave absorption in the ionosphere is a function of electron density, collision frequency, radio wave polarisation, magnetic field and radio wave frequency. Several studies have used multi-frequency measurements of cosmic radio noise absorption
Externí odkaz:
https://doaj.org/article/c562d4757bbd4343b45fd21e8dbd05de
Autor:
D. K. Whiter, H. Sundberg, B. S. Lanchester, J. Dreyer, N. Partamies, N. Ivchenko, M. Z. Di Fraia, R. Oliver, A. Serpell-Stevens, T. Shaw-Diaz, T. Braunersreuther
Publikováno v:
Annales Geophysicae, Vol 39, Pp 975-989 (2021)
Fragmented aurora-like emissions (FAEs) are small (few kilometres) optical structures which have been observed close to the poleward boundary of the aurora from the high-latitude location of Svalbard (magnetic latitude 75.3 ∘N). The FAEs are only v
Externí odkaz:
https://doaj.org/article/98d6df1010964ae1985c3d009f994286
Publikováno v:
Annales Geophysicae, Vol 39, Pp 883-897 (2021)
Recent simulation studies have provided evidence that a pulsating aurora (PsA) associated with high-energy electron precipitation is having a clear local impact on ozone chemistry in the polar middle mesosphere. However, it is not clear if the PsA is
Externí odkaz:
https://doaj.org/article/11246b2294d840ba9628bebbe9c0bdde