Predicting Melt Pond Fraction on Landfast Snow Covered First Year Sea Ice from Winter C-Band SAR Backscatter Utilizing Linear, Polarimetric and Texture Parameters

Early-summer melt pond fraction is predicted using late-winter C-band backscatter of snow-covered first-year sea ice. Aerial photographs were acquired during an early-summer 2012 field campaign in Resolute Passage, Nunavut, Canada, on smooth first-year sea ice to estimate the melt pond fraction. RADARSAT-2 Synthetic Aperture Radar (SAR) data were acquired over the study area in late winter prior to melt onset. Correlations between the melt pond fractions and late-winter linear and polarimetric SAR parameters and texture measures derived from the SAR parameters are utilized to develop multivariate regression models that predict melt pond fractions. The results demonstrate substantial capability of the regression models to predict melt pond fractions for all SAR incidence angle ranges. The combination of the most significant linear, polarimetric and texture parameters provide the best model at far-range incidence angles, with an R 2 of 0.62 and a pond fraction RMSE of 0.09. Near- and mid- range incidence angle models provide R 2 values of 0.57 and 0.61, respectively, with an RMSE of 0.11. The strength of the regression models improves when SAR parameters are combined with texture parameters. These predictions also serve as a proxy to estimate snow thickness distributions during late winter as higher pond fractions evolve from thinner snow cover.

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Snow Thickness Estimation on First-Year Sea Ice from Late Winter Spaceborne Scatterometer Backscatter Variance

Remote Sensing ◽

10.3390/rs11040417 ◽

2019 ◽

Vol 11 (4) ◽

pp. 417 ◽

Cited By ~ 5

Author(s):

John Yackel ◽

Torsten Geldsetzer ◽

Mallik Mahmud ◽

Vishnu Nandan ◽

Stephen Howell ◽

...

Keyword(s):

Sea Ice ◽

Snow Cover ◽

Winter Season ◽

Late Winter ◽

First Year ◽

Snow Layer ◽

Independent Case ◽

Brine Volume ◽

Snow Thickness

Ku- and C-band spaceborne scatterometer sigma nought (σ°) backscatter data of snow covered landfast first-year sea ice from the Canadian Arctic Archipelago are acquired during the winter season with coincident in situ snow-thickness observations. Our objective is to describe a methodological framework for estimating relative snow thickness on first-year sea ice based on the variance in σ° from daily time series ASCAT and QuikSCAT scatterometer measurements during the late winter season prior to melt onset. We first describe our theoretical basis for this approach, including assumptions and conditions under which the method is ideally suited and then present observational evidence from four independent case studies to support our hypothesis. Results suggest that the approach can provide a relative measure of snow thickness prior to σ° detected melt onset at both Ku- and C-band frequencies. We observe that, during the late winter season, a thinner snow cover displays a larger variance in daily σ° compared to a thicker snow cover on first-year sea ice. This is because for a given increase in air temperature, a thinner snow cover manifests a larger increase in basal snow layer brine volume owing to its higher thermal conductivity, a larger increase in the dielectric constant and a larger increase in σ° at both Ku- and C bands. The approach does not apply when snow thickness distributions on first-year sea ice being compared are statistically similar, indicating that similar late winter σ° variances likely indicate regions of similar snow thickness.

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Arctic summer sea-ice SAR signatures, melt-season characteristics, and melt-pond fractions

Polar Record ◽

10.1017/s003224740001442x ◽

1997 ◽

Vol 33 (185) ◽

pp. 101-112 ◽

Cited By ~ 15

Author(s):

M. O. Jeffries ◽

K. Schwartz ◽

S. Li

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

Late Summer ◽

Beaufort Sea ◽

Early Summer ◽

The Arctic ◽

Late Winter ◽

Melt Pond ◽

Melt Ponds ◽

The Arctic Ocean

AbstractVariations in multiyear sea-ice backscatter from the synthetic aperture radar (SAR) aboard the ERS-1 satellite are interpreted in terms of melt-season characteristics (onset of melt in spring and of freeze-up in autumn, and the duration of the snow-decay period, the melt season, and the melt-pond season) from late winter to early autumn 1992 in two regions of the Arctic Ocean: the northeastern Beaufort Sea adjacent to the Queen Elizabeth Islands in the Canadian high Arctic and the western Beaufort Sea north of Alaska. In the northeastern Beaufort Sea, the onset of melt occurs later, and the periods of snow-cover decay and the occurrence of melt ponds are shorter than in the western Beaufort Sea. These melt-season characteristics of each area are consistent with previous observations that the northeastern Beaufort Sea has one of the most severe summer climates in the Arctic Ocean. A model, which assumes that the backscatter from multiyear floes is the sum of backscatter from bare ice and melt ponds, is used to derive the melt-pond fraction during the summer. The results show that melt-pond fractions decrease from an early-summer maximum of about 60% to a late-summer minimum around 10%. The magnitude of the melt-pond fractions and their decline during the summer is consistent with previous, more qualitative data. The SAR model, which gives melt-pond fractions with lower variability and less uncertainty than previous data, offers an improved approach to the reliable estimation of the areal extent of water on ice floes. Suggestions for further improvement of the model include accounting for the consequences of wind-speed variations, summer snowfall, and freeze/thaw cycles and their effects on melt-pond and ice-surface roughness.

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Comparison of Ascat Estimated Snow Thickness on First-Year Sea Ice in the Canadian Arctic with Modeled and Passive Microwave Data

IGARSS 2020 - 2020 IEEE International Geoscience and Remote Sensing Symposium ◽

10.1109/igarss39084.2020.9323947 ◽

2020 ◽

Author(s):

John J. Yackel ◽

Torsten Geldsetzer ◽

Mallik Mahmud ◽

Rory Armstrong ◽

Vishnu Nandan ◽

...

Keyword(s):

Sea Ice ◽

Canadian Arctic ◽

Passive Microwave ◽

First Year ◽

Snow Thickness ◽

Microwave Data

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Albedo of Young and First-Year Antarctic Sea Ice

Annals of Glaciology ◽

10.1017/s0260305500008909 ◽

1990 ◽

Vol 14 ◽

pp. 331 ◽

Cited By ~ 2

Author(s):

Richard Brandt ◽

Ian Allison ◽

Stephen Warren

Keyword(s):

Sea Ice ◽

Radiation Flux ◽

Open Water ◽

First Year ◽

Spectral Measurements ◽

Antarctic Sea Ice ◽

Antarctic Expedition ◽

Downward Radiation ◽

Radiation Measurements ◽

Snow Thickness

Reflection of solar radiation was studied in the seasonal sea-ice zone off East Antarctica on a cruise of the Australian Antarctic Expedition, October-December 1988. Spectral and total albedos were measured for grease ice, nilas, young grey ice, grey-white ice, snow-covered ice, and open water. Spectral measurements covered the region 400–1000 nm wavelength. For ice too thin to support our weight, the radiometers were mounted at the end of a 1.5 m rod extended out the door of a helicopter or from a basket hung from the ship's crane, using a positioning and leveling rack. Corrections had to be applied to the downward radiation flux because the helicopter or the crane was in the field of view of the cosine-collector. The fractional coverage of each of the ice types (and open water) was estimated hourly for the region near the ship, as well as the thickness of each ice type, and the snow thickness. Observations were carried out continuously during the four weeks the ship was in the ice, supplemented by occasional helicopter surveys covering larger areas. These observations, together with the radiation measurements, make possible the computation of area-average albedo for the East Antarctic sea-ice zone in spring.

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A Field Study of Brine Drainage and Oil Entrainment in First-Year Sea Ice

Journal of Glaciology ◽

10.3189/s0022143000014477 ◽

1979 ◽

Vol 22 (88) ◽

pp. 473-502 ◽

Cited By ~ 5

Author(s):

Seelye Martin

Keyword(s):

Sea Ice ◽

Growth And Development ◽

Salt Transport ◽

First Year ◽

Field Observations ◽

Melt Pond ◽

Ice Surface ◽

Melt Ponds ◽

Brine Channel ◽

Horizontal Layers

AbstractFrom field observations this paper describes the growth and development of first-year sea ice and its interaction with petroleum. In particular, when sea ice initially forms, there is an upward salt transport so that the ice surface has a highly saline layer, regardless of whether the initial ice is frazil, columnar, or slush ice. When the ice warms in the spring, because of the eutectic condition, the surface salt liquifies and drains through the ice, leading to the formation of top-to-bottom brine channels and void spaces in the upper part of the ice. If oil is released beneath winter ice, then the oil becomes entrained in thin lenses within the ice. In the spring, this oil flows up to the surface through the newly-opened brine channels and distributes itself within the brine-channel feeder systems, on the ice surface, and in horizontal layers in the upper part of the ice. The paper shows that these layers probably form from the interaction of the brine drainage with the percolation of melt water from surface snow down into the ice and the rise of the oil from below. Finally in the summer, the oil on the surface leads to melt-pond formation. The solar energy absorbed by the oil on the surface of these melt ponds eventually causes the melt pond to melt through the ice, and the oil is again released into the ocean.

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Investigation of spatiotemporal variability of melt pond fraction and its relationship with sea ice extent during 2000–2017 using a new data

10.5194/tc-2019-208 ◽

2019 ◽

Author(s):

Yifan Ding ◽

Xiao Cheng ◽

Jiping Liu ◽

Fengming Hui ◽

Zhenzhan Wang

Keyword(s):

Sea Ice ◽

Arctic Basin ◽

Beaufort Sea ◽

Arctic Sea Ice ◽

Spatiotemporal Variability ◽

First Year ◽

Spatial And Temporal Variability ◽

Sea Ice Extent ◽

Melt Pond ◽

Melt Ponds

Abstract. The accurate knowledge of variations of melt ponds is important for understanding Arctic energy budget due to its albedo-transmittance-melt feedback. In this study, we develop and validate a new method for retrieving melt pond fraction (MPF) from the MODIS surface reflectance. We construct an ensemble-based deep neural network and use in-situ observations of MPF from multi-sources to train the network. The results show that our derived MPF is in good agreement with the observations, and relatively outperforms the MPF retrieved by University of Hamburg. Built on this, we create a new MPF data from 2000 to 2017 (the longest data in our knowledge), and analyze the spatial and temporal variability of MPF. It is found that the MPF has significant increasing trends from late July to early September, which is largely contributed by the MPF over the first-year sea ice. The analysis based on our MPF during 2000–2017 confirms that the integrated MPF to late June does promise to improve the prediction skill of seasonal Arctic sea ice minimum. However, our MPF data shows concentrated significant correlations first appear in a band, extending from the eastern Beaufort Sea, through the central Arctic, to the northern East Siberian and Laptev Seas in early-mid June, and then shifts towards large areas of the Beaufort Sea, Canadian Arctic, the northern Greenland Sea and the central Arctic basin.

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First-Year and Multiyear Sea Ice Incidence Angle Normalization of Dual-Polarized Sentinel-1 SAR Images in the Beaufort Sea

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing ◽

10.1109/jstars.2020.2977506 ◽

2020 ◽

Vol 13 ◽

pp. 1540-1550 ◽

Cited By ~ 2

Author(s):

Wiebke Aldenhoff ◽

Leif E. B. Eriksson ◽

Yufang Ye ◽

Celine Heuze

Keyword(s):

Sea Ice ◽

Incidence Angle ◽

Beaufort Sea ◽

First Year ◽

Sar Images ◽

Dual Polarized

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Monitoring evolution of melt ponds on first-year and multiyear sea ice in the Canadian Arctic Archipelago with optical satellite data

Annals of Glaciology ◽

10.1017/aog.2020.24 ◽

2020 ◽

Vol 61 (82) ◽

pp. 154-163

Author(s):

Qing Li ◽

Chunxia Zhou ◽

Lei Zheng ◽

Tingting Liu ◽

Xiaotong Yang

Keyword(s):

Sea Ice ◽

Canadian Arctic ◽

Arctic Sea Ice ◽

First Year ◽

Landsat 8 ◽

Canadian Arctic Archipelago ◽

Melt Pond ◽

Melt Ponds ◽

Validation Experiment ◽

Multiyear Ice

AbstractThe evolution of melt ponds on Arctic sea ice in summer is one of the main factors that affect sea-ice albedo and hence the polar climate system. Due to the different spectral properties of open water, melt pond and sea ice, the melt pond fraction (MPF) can be retrieved using a fully constrained least-squares algorithm, which shows a high accuracy with root mean square error ~0.06 based on the validation experiment using WorldView-2 image. In this study, the evolution of ponds on first-year and multiyear ice in the Canadian Arctic Archipelago was compared based on Sentinel-2 and Landsat 8 images. The relationships of pond coverage with air temperature and albedo were analysed. The results show that the pond coverage on first-year ice changed dramatically with seasonal maximum of 54%, whereas that on multiyear ice changed relatively flat with only 30% during the entire melting period. During the stage of pond formation, the ponds expanded rapidly when the temperature increased to over 0°C for three consecutive days. Sea-ice albedo shows a significantly negative correlation (R = −1) with the MPF in melt season and increases gradually with the refreezing of ponds and sea ice.

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First-year sea ice melt pond fraction estimation from dual-polarisation C-band SAR – Part 1: In situ observations

The Cryosphere ◽

10.5194/tc-8-2147-2014 ◽

2014 ◽

Vol 8 (6) ◽

pp. 2147-2162 ◽

Cited By ~ 15

Author(s):

R. K. Scharien ◽

J. Landy ◽

D. G. Barber

Keyword(s):

Sea Ice ◽

Climate Model ◽

Morphological Changes ◽

Weather Forecast ◽

Equation Model ◽

Arctic Sea Ice ◽

First Year ◽

Ice Melt ◽

Melt Pond

Abstract. Understanding the evolution of melt ponds on Arctic sea ice is important for climate model parameterisations, weather forecast models and process studies involving mass, energy and biogeochemical exchanges across the ocean–sea ice–atmosphere interface. A field campaign was conducted in a region of level first-year sea ice (FYI) in the central Canadian Arctic Archipelago (CAA), during the summer of 2012, to examine the potential for estimating melt pond fraction (fp) from satellite synthetic aperture radar (SAR). In this study, 5.5 GHz (C-band) dual co- (HH + VV – horizontal transmit and horizontal receive + vertical transmit and vertical receive) and cross-polarisation (HV + HH – horizontal transmit and vertical receive + horizontal transmit and horizontal receive) radar scatterometer measurements of melt-pond-covered FYI are combined with ice and pond properties to analyse the effects of in situ physical and morphological changes on backscatter parameters. Surface roughness statistics of ice and ponds are characterised and compared to the validity domains of the Bragg and integral equation model (IEM) scattering models. Experimental and model results are used to outline the potential and limitations of the co-polarisation ratio (VV / HH) for retrieving melt pond information, including fp, at large incidence angles (≥35°). Despite high variability in cross-polarisation ratio (HV / HH) magnitudes, increases at small incidence angles (<30°) are attributed to the formation of ice lids on ponds. Implications of the results for pond information retrievals from satellite C-, L- and P-band SARs are discussed.

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