Match!
John J. Yackel
University of Calgary
76Publications
20H-index
1,112Citations
Publications 76
Newest
Abstract Information on the timing of melt onset over sea ice is important for understanding the Arctic's changing climate. The daily temporal resolution of passive microwave brightness temperatures provides the most widely utilized observations to detect melt onset but are limited to a spatial resolution of 25 km. Wide-swath synthetic aperture radar (SAR) imagery provides a much higher spatial resolution (20–100 m) but melt onset detection remains challenging because of i) insufficient temporal...
#1John J. YackelH-Index: 20
#2Torsten GeldsetzerH-Index: 12
view all 7 authors...
This research was funded by Canadian NSERC Discovery grants to John Yackel and Randy Scharien as well as Polar Continental Shelf Project and Polar Knowledge Canada support to C.J. Mundy, Brent Else, Randy Scharien and John Yackel. The APC was funded by Canadian NSERC Discovery grants to John Yackel.
#1Mallik Sezan Mahmud (U of C: University of Calgary)H-Index: 5
#2Torsten Geldsetzer (U of C: University of Calgary)H-Index: 12
Last.Randall K. Scharien (UVic: University of Victoria)H-Index: 13
view all 6 authors...
Synthetic aperture radar (SAR) incidence angle has a significant effect on the microwave backscatter from sea ice. This paper investigates the incidence angle dependence of C- and L-band HH-polarized microwave backscatter coefficient over Arctic first-year sea ice (FYI) and multiyear sea ice (MYI) in winter. Advanced Land Observation Satellite Phased Array type L-band SAR (L-band) and RADARSAT-2 (C-band) images are used to derive ice type-specific incidence angle dependencies calculated using li...
#2Alexander KomarovH-Index: 17
Last.John J. Yackel (U of C: University of Calgary)H-Index: 20
view all 10 authors...
Abstract Estimating sea ice motion from synthetic aperture radar (SAR) imagery at C-band is the most reliable approach because of its high spatial resolution and ever increasing temporal resolution given the multiple current and upcoming SAR platforms. However, there is still uncertainty in SAR derived sea ice motion depending on the ice type and its thermodynamic state. There have been suggestions (mostly theoretical) that use of L-band SAR and its inherent longer wavelength (15–30 cm) and subs...
#1John J. Yackel (U of C: University of Calgary)H-Index: 20
#2Vishnu Nandan (U of C: University of Calgary)H-Index: 4
Last.Torsten Geldsetzer (U of C: University of Calgary)H-Index: 12
view all 6 authors...
Abstract Melt ponds play a significant role in the summer decay of sea ice due to the fact that their albedo is significantly lower than surrounding snow and sea ice surface. Despite its requirement for thermodynamic sea ice modeling, measurement of melt pond areal coverage using satellite remote sensing has proven difficult due to significant spatiotemporal variability in the timing and evolution of melt ponds. Less than optimal results from prior studies employing a spectral mixture analysis (...
#1Vishnu Nandan (U of C: University of Calgary)H-Index: 4
#2Torsten Geldsetzer (U of C: University of Calgary)H-Index: 12
Last.Brent Else (U of C: University of Calgary)H-Index: 19
view all 9 authors...
#1Vishnu Nandan (U of C: University of Calgary)H-Index: 4
#2Torsten Geldsetzer (U of C: University of Calgary)H-Index: 12
Last.Brent Else (U of C: University of Calgary)H-Index: 19
view all 9 authors...
The European Space Agency's CryoSat-2 satellite mission provides radar altimeter data that are used to derive estimates of sea ice thickness and volume. These data are crucial to understanding recent variability and changes in Arctic sea ice. Sea ice thickness retrievals at the CryoSat-2 frequency require accurate measurements of sea ice freeboard, assumed to be attainable when the main radar scattering horizon is at the snow/sea ice interface. Using an extensive snow thermophysical property dat...
12345678