Albedo and Depth of Melt Ponds on Sea-Ice

Abstract

For a 1‐month period during the spring–summer season, over 500 in situ measurements of the albedo, depth and selected properties of melt ponds were made at four sea‐ice sites in the Canadian Arctic Archipelago. There are three aims of the investigation: to examine the variation in spectral reflectance of melt ponds in relation primarily to clouds, pond depth, and ice type; to compute and assess with reliability, and for the first time, the statistical properties of pond depth; and to derive pond albedo parameterizations for implementation in sea‐ice model simulations. It was found that pond reflectance curves vary significantly with cloud cover, pond depth, and ice type. A simple univariate statistical analysis showed that surface ice morphology controls pond depth. Application of the Kruskal–Wallis test evidenced that differences between first‐year ice, multi‐year ice, and landfast ice‐pond‐depth distributions are statistically significant. Lastly, calibrated non‐linear regression functions show that visible and near‐infrared pond albedos decrease exponentially with depth until some critical depth value is exceeded. The relationship is weakest in the visible spectrum, particularly under cloudy sky conditions.

A model of melt pond evolution on sea ice

“…The most informative diagnostic of the simulations is the maximum melt pond depth. This is because it can be directly compared to observations and is routinely measured in field studies of melt ponds [e.g., Eicken et al , 1994; Morassutti and LeDrew , 1996; Perovich et al , 1999]. The pond depth is also crucial in determining the albedo of melt pond covered sea ice and is utilized in parameterizations of melt pond albedo [e.g., Ebert and Curry , 1993; Morassutti and LeDrew , 1996].…”

A physical algorithm to measure sea ice concentration from passive microwave remote sensing data

“…Because of low albedo they absorb multiple times greater short-wave radiation than the rest of the snow and ice cover (Grenfell and Perovich, 1984;Tschudi et al, 2008). The depth of melt ponds can vary from a few centimeters to 1.5 meters (Morassutti and Ledrew, 1996;Perovich et al, 2003). Their horizontal size can reach hundreds of square meters (Polashenski et al, 2012;Tucker et al, 1999).…”

Changes in the modeled ice thickness distribution near the Surface Heat Budget of the Arctic Ocean (SHEBA) drifting ice camp

“…The albedo algorithm is based on the Ebert and Curry [1993] albedo parameterization with an improved pond parameterization as reported by Schramm et al [1997]. The improvements are based on the pond albedo observations reported by Morassutti and LeDrew [1996]. The model includes five surface types (dry snow, melting snow, bare ice, melt ponds, and open water) and four spectral bands (0.25–0.69, 0.69–1.19, 1.19–2.38, and 2.38–4.00 μm).…”