John J. Yackel
University of Calgary
GeologySea iceArctic ice packSnowRemote sensing
What is this?
Publications 76
Uncertainty in snow properties impacts the accuracy of Arctic sea ice thickness estimates from radar altimetry. On first-year sea ice (FYI), spatiotemporal variations in snow properties can cause the Ku-band main radar scattering horizon to appear above the snow/sea ice interface. This can increase the estimated sea ice freeboard by several centimeters, leading to FYI thickness overestimations. This article examines the expected changes in Ku-band main scattering horizon and its impact on FYI th...
1 CitationsSource
#1Michael Kern (ESA: European Space Agency)H-Index: 7
#2Robert Cullen (ESA: European Space Agency)H-Index: 9
Last. Rolv Midthassel (ESA: European Space Agency)H-Index: 2
view all 26 authors...
Abstract. One of the candidate missions in the evolution of the Copernicus Space Component (CSC) is the Copernicus polaR Ice and Snow Topography ALtimeter (CRISTAL). The aim of this mission is to obtain high-resolution sea-ice thickness and land ice elevation measurements and includes the capability to determine the properties of snow cover on ice to serve Copernicus’ operational products and services of direct relevance to the Polar Regions. The evolution of the CSC is foreseen in the mid-2020s...
#1Woosok MoonH-Index: 6
#2Vishnu Nandan (U of C: University of Calgary)H-Index: 4
Last. Brent Else (U of C: University of Calgary)H-Index: 19
view all 12 authors...
#2David Small (UZH: University of Zurich)H-Index: 16
Last. Michael BradyH-Index: 3
view all 6 authors...
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 resoluti...
2 CitationsSource
#1John J. YackelH-Index: 20
#2Torsten GeldsetzerH-Index: 5
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.
#1Saroat RamjanH-Index: 1
#2Torsten GeldsetzerH-Index: 5
Last. John J. YackelH-Index: 20
view all 4 authors...
#1Randall K. ScharienH-Index: 13
#2Rebecca SegalH-Index: 3
Last. Sasha NasonovaH-Index: 2
view all 5 authors...
1 CitationsSource
#1Mallik Sezan Mahmud (U of C: University of Calgary)H-Index: 5
#2Torsten Geldsetzer (U of C: University of Calgary)H-Index: 5
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...
3 CitationsSource
#2Alexander KomarovH-Index: 21
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...
3 CitationsSource
#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: 5
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 (...
1 CitationsSource