Snow Albedo Seasonality and Trend from MODIS Sensor and Ground Data at Johnsons Glacier, Livingston Island, Maritime Antarctica

The aim of this work is to investigate whether snow albedoseasonality and trend under all sky conditions at Johnsons Glacier (Livingston Island, Antarctica) can be tracked using the Moderate Resolution Imaging Spectroradiometer(MODIS) snow albedodaily product MOD10A1. The time span is from December 2006 to February 2015. As the MOD10A1 snow albedoproduct has never been used in Antarctica before, we also assess the performance for the MOD10A1 cloud mask. The motivation for this work is the need for a description of snow albedounder all sky conditions (including overcastdays) using satellite data with mid-spatial resolution. In-situ albedowas filtered with a 5-day windowed moving average, while the MOD10A1 data were filtered using a maximum filter. Both in-situ and MOD10A1 data follow an exponential decay during the melting season, with a maximum decay of 0.049/0.094 day−1 (in-situ/MOD10A1) for the 2006–2007 season and a minimum of 0.016/0.016 day−1 for the 2009–2010 season. The duration of the decay varies from 85 days (2007–2008) to 167 days (2013–2014). Regarding the albedotrend, both data sets exhibit a slight increase of albedo, which may be explained by an increase of snowfall along with a decrease of snowmeltin the study area. Annual albedoincreases of 0.2% and 0.7% are obtained for in-situ and MOD10A1 data, respectively, which amount to respective increases of 2% and 6% in the period 2006–2015. We conclude that MOD10A1 can be used to characterize snow albedoseasonality and trend on Livingston Island when filtered with a maximum filter.