Papers by Alexey Naumenko
Surveys in Geophysics, 2008
We show how the studies of ice and snow cover of continental water bodies can benefit from the sy... more We show how the studies of ice and snow cover of continental water bodies can benefit from the synergy of more than 15 years-long simultaneous active (radar altimeter) and passive (radiometer) observations from radar altimetric satellites (TOPEX/Poseidon, Jason-1, ENVISAT and Geosat Follow-On) and how this approach can be complemented by SSM/I passive microwave data to improve spatial and temporal coverage. Five largest Eurasian continental water bodies—Caspian and Aral seas, Baikal, Ladoga and Onega lakes are selected as examples. First we provide an overview of ice regime and history of ice studies for these seas and lakes. Then a summary of the existing state of the art of ice discrimination methodology from altimetric observations and SSM/I is given. The drawbacks and benefits of each type of sensor and particularities of radiometric properties for each of the chosen water bodies are discussed. Influence of sensor footprint size, ice roughness and snow cover on satellite measurements is also addressed. A step-by-step ice discrimination approach based on a combined use of the data from the four altimetric missions and SSM/I is presented, as well as validation of this approach using in situ and independent satellite data in the visible range. The potential for measurement of snow depth on ice from passive microwave observations using both altimeters and SSM/I is addressed and a qualitative comparison of in situ snow depth observations and satellite-derived estimates is made.
Jetp Letters, 1997
The real and imaginary parts of the surface impedance Z s =R s +iX s of YBa2Cu3O6.95 single cryst... more The real and imaginary parts of the surface impedance Z s =R s +iX s of YBa2Cu3O6.95 single crystals are measured at a frequency ω/π=9.4 GHz. The quantities R s (T) and X s (T) are linear functions of temperature for TT c (T c =93.5 K). A maximum of R s (T) and a plateau of X s (T) are observed in the interval 35TR s (T) in YBa2Cu3O6.95 single crystals in the temperature range 0TT c , are described well in a two-fluid model which assumes electron-phonon scattering of quasiparticles.
Uploads
Papers by Alexey Naumenko