2,727 research outputs found
Polarimetric phase-sensitive radar measurements at EastGRIP drill site, 2019
No full textPolarimetric phase-sensitive Radio Echo Sounder (PpRES) measurements at EastGRIP drill site on the Northeast Greenland Ice Stream. PpRES_CL are measurements from the science trench next to the core location (CL) roughly 8 m below the surface. The other measurements (PpRES_GRID_C, PpRES_GRID_N, PpRES_GRID_E, PpRES_GRID_S and PpRES_GRID_W) were performed within a 20x20 m^2 grid (named GRID) approximately 360 m from the drill site. The transmitting and the receiving antenna of PpRES_CL were aligned with vertical polarisation (VV) at an azimuthal angle of roughly 258° clockwise to magnetic North (283° true North). The antennas of GRID-measurements were aligned at an azimuthal angle of roughly 168° clockwise to magnetic North (193° true North). The file names include the degree of the measurement representing the orientation of the antennas (clockwise rotation) to the originally pointed angle. The referenzed figure visualises all antenna orientations along with two types of notation. Data were measured in the field by Ole Zeising and Angelika Humbert. Data has been acquired at the EastGRIP camp that kindly hosted this activity as an associate project. EastGRIP is directed and organized by the Centre for Ice and Climate at the Niels Bohr Institute, University of Copenhagen. It is supported by funding agencies and institutions in Denmark (A. P. Møller Foundation, University of Copenhagen), USA (US National Science Foundation, Office of Polar Programs), Germany (Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research), Japan (National Institute of Polar Research and Arctic Challenge for Sustainability), Norway (University of Bergen and Trond Mohn Foundation), Switzerland (Swiss National Science Foundation), France (French Polar Institute Paul-Emile Victor, Institute for Geosciences and Environmental research), Canada (University of Manitoba) and China (Chinese Academy of Sciences and Beijing Normal University). If you have questions, please contact Ole Zeising ([email protected]) or co-authors
Polarimetric Cross-Correlation Method
No full textThese MATLAB scripts apply the polarimetric cross-correlation approach on co-polarised pRES raw data (HH and VV) to analyse the bulk ice fabric asymmetry. It produces the figure 2 and results from Zeising et al. (2023).Please contact [email protected] in case of questions
Time series of autonomous phase-sensitive radar (ApRES) measurements for basal melt rate estimations at location ApRES1 on 79°N Glacier from August 2016 to June 2022
No full textThe dataset consists of raw data from autonomous phase-sensitive radar (ApRES) measurements. The ApRES was operated with two bow-tie antennas on the surface in the ablation zone of the 79°N Glacier in Northeast Grenland since 2016. These Lagrangian measurements allow the estimation of basal melt rates based on estimated vertical displacements of englacial and basal reflections. The ApRES is an autonomous operating frequency-modulated continuous wave (FMCW) radar that transmits a tone sweep – called chirp – ranging from 200 to 400 MHz over a period of one second. In order to improve the signal-to-noise ratio, 20 to 100 chirps were transmitted within a single measurement. These measurements were repeated at time intervals between 15 minutes and 6 hours. A raw data file contains up to 4 measurements. Background of the pRES-system is published by Nicholls et al. (2015). The processing of the data is described in Zeising et al. (2024)
Time series of autonomous phase-sensitive radar (ApRES) measurements for basal melt rate estimations at 79°N Glacier
No full textThe dataset consists of raw data from autonomous phase-sensitive radar (ApRES) measurements. The ApRES was operated with two bow-tie antennas on the surface in the ablation zone of the 79°N Glacier in Northeast Grenland since 2016. These Lagrangian measurements allow the estimation of basal melt rates based on estimated vertical displacements of englacial and basal reflections. The ApRES is an autonomous operating frequency-modulated continuous wave (FMCW) radar that transmits a tone sweep – called chirp – ranging from 200 to 400 MHz over a period of one second. In order to improve the signal-to-noise ratio, 20 to 100 chirps were transmitted within a single measurement. These measurements were repeated at time intervals between 15 minutes and 6 hours. A raw data file contains up to 4 measurements. Background of the pRES-system is published by Nicholls et al. (2015). The processing of the data is described in Zeising et al. (2024)
Time series of autonomous phase-sensitive radar (ApRES) measurements for basal melt rate estimations at location ApRES4 on 79°N Glacier from July 2017 to July 2022
No full textThe dataset consists of raw data from autonomous phase-sensitive radar (ApRES) measurements. The ApRES was operated with two bow-tie antennas on the surface in the ablation zone of the 79°N Glacier in Northeast Grenland since 2016. These Lagrangian measurements allow the estimation of basal melt rates based on estimated vertical displacements of englacial and basal reflections. The ApRES is an autonomous operating frequency-modulated continuous wave (FMCW) radar that transmits a tone sweep – called chirp – ranging from 200 to 400 MHz over a period of one second. In order to improve the signal-to-noise ratio, 20 to 100 chirps were transmitted within a single measurement. These measurements were repeated at time intervals between 15 minutes and 6 hours. A raw data file contains up to 4 measurements. Background of the pRES-system is published by Nicholls et al. (2015). The processing of the data is described in Zeising et al. (2024)
Time series of autonomous phase-sensitive radar (ApRES) measurements for basal melt rate estimations at location ApRES2a on 79°N Glacier from August 2016 to July 2018
No full textThe dataset consists of raw data from autonomous phase-sensitive radar (ApRES) measurements. The ApRES was operated with two bow-tie antennas on the surface in the ablation zone of the 79°N Glacier in Northeast Grenland since 2016. These Lagrangian measurements allow the estimation of basal melt rates based on estimated vertical displacements of englacial and basal reflections. The ApRES is an autonomous operating frequency-modulated continuous wave (FMCW) radar that transmits a tone sweep – called chirp – ranging from 200 to 400 MHz over a period of one second. In order to improve the signal-to-noise ratio, 20 to 100 chirps were transmitted within a single measurement. These measurements were repeated at time intervals between 15 minutes and 6 hours. A raw data file contains up to 4 measurements. Background of the pRES-system is published by Nicholls et al. (2015). The processing of the data is described in Zeising et al. (2024)
Time series of autonomous phase-sensitive radar (ApRES) measurements for basal melt rate estimations at location ApRES2b on 79°N Glacier from July 2018 to February 2020
No full textThe dataset consists of raw data from autonomous phase-sensitive radar (ApRES) measurements. The ApRES was operated with two bow-tie antennas on the surface in the ablation zone of the 79°N Glacier in Northeast Grenland since 2016. These Lagrangian measurements allow the estimation of basal melt rates based on estimated vertical displacements of englacial and basal reflections. The ApRES is an autonomous operating frequency-modulated continuous wave (FMCW) radar that transmits a tone sweep – called chirp – ranging from 200 to 400 MHz over a period of one second. In order to improve the signal-to-noise ratio, 20 to 100 chirps were transmitted within a single measurement. These measurements were repeated at time intervals between 15 minutes and 6 hours. A raw data file contains up to 4 measurements. Background of the pRES-system is published by Nicholls et al. (2015). The processing of the data is described in Zeising et al. (2024)
Time series of autonomous phase-sensitive radar (ApRES) measurements for basal melt rate estimations at location ApRES3 on 79°N Glacier from July 2017 to September 2023
No full textThe dataset consists of raw data from autonomous phase-sensitive radar (ApRES) measurements. The ApRES was operated with two bow-tie antennas on the surface in the ablation zone of the 79°N Glacier in Northeast Grenland since 2016. These Lagrangian measurements allow the estimation of basal melt rates based on estimated vertical displacements of englacial and basal reflections. The ApRES is an autonomous operating frequency-modulated continuous wave (FMCW) radar that transmits a tone sweep – called chirp – ranging from 200 to 400 MHz over a period of one second. In order to improve the signal-to-noise ratio, 20 to 100 chirps were transmitted within a single measurement. These measurements were repeated at time intervals between 15 minutes and 6 hours. A raw data file contains up to 4 measurements. Background of the pRES-system is published by Nicholls et al. (2015). The processing of the data is described in Zeising et al. (2024)
Ole Miss Faculty and Staff Retirees Invited to Presentation
No full textLocal historian and author Jack Mayfield to speak at Inn at Ole Mis
Ole Miss Faculty and Staff Retirees Invited to Presentation
No full textLocal historian and author Jack Mayfield to speak at Inn at Ole Mis
- …
