Blar i forfatter "Hoffmann, Peter"

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    • Localized mesosphere-stratosphere-troposphere radar echoes from the E region at 69 degrees N: Properties and physical mechanisms 

      Rapp, Markus; Leitert, Lasse; Latteck, Ralph; Zecha, Marius; Hoffmann, Peter; Höffner, Josef; Hoppe, Ulf-Peter; La Hoz, Cesar; Thrane, Eivind (Journal article; Tidsskriftartikkel; Peer reviewed, 2011-02-25)
      We present the first observations, to our knowledge, of a new class of high‐latitude mesosphere‐stratosphere‐troposphere radar echoes from the E region as observed with the Arctic Lidar Observatory for Middle Atmosphere Research wind radar during the period 2004–2008. These echoes occur primarily during the summer months and in the altitude range from 93 to 114 km, with a pronounced peak of maximum ...

    • Long-term studies of mesosphere and lower-thermosphere summer length definitions based on mean zonal wind features observed for more than one solar cycle at middle and high latitudes in the Northern Hemisphere 

      Jaen, Juliana; Renkwitz, Toralf; Chau, Jorge L.; He, Maosheng; Hoffmann, Peter; Yamazaki, Yosuke; Jacobi, Christoph; Tsutsumi, Masaki; Matthias, Vivien; Hall, Chris (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-20)
      Specular meteor radars (SMRs) and partial reflection radars (PRRs) have been observing mesospheric winds for more than a solar cycle over Germany (∼ 54◦ N) and northern Norway (∼ 69◦ N). This work investigates the mesospheric mean zonal wind and the zonal mean geostrophic zonal wind from the Microwave Limb Sounder (MLS) over these two regions between 2004 and 2020. Our study focuses on the ...

    • Zonal Wave Number Diagnosis of Rossby Wave-Like Oscillations Using Paired Ground-Based Radars 

      He, Maosheng; Yamazaki, Yosuke; Hoffmann, Peter; Hall, Chris; Tsutsumi, Masaki; Li, Guozhu; Chau, Jorge L. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-03)
      Free traveling Rossby wave normal modes (RNMs) are often investigated through large-scale space-time spectral analyses, which therefore is subject to observational availability, especially in the mesosphere. Ground-based mesospheric observations were broadly used to identify RNMs mostly according to the periods of RNMs without resolving their horizontal scales. The current study diagnoses zonal ...

    • Zonal wavenumber diagnosis of Rossby-wave-like oscillations using paired ground-based radars 

      He, Maosheng; Yamazaki, Yosuke; Hoffmann, Peter; Hall, Chris M.; Tsutsumi, Masaki; Li, Guozhu; Chau, Jorge Luis (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-03)
      Free traveling Rossby wave normal modes (RNMs) are often investigated through large‐scale space‐time spectral analyses, which therefore is subject to observational availability, especially in the mesosphere. Ground‐based mesospheric observations were broadly used to identify RNMs mostly according to the periods of RNMs without resolving their horizontal scales. The current study diagnoses zonal wave ...