Response of ice cover on shallow lakes of the North Slope of Alaska to contemporary climate conditions (1950–2011): radar remote-sensing and numerical modeling data analysis

摘要: Abstract. Air temperature and winter precipitation changes over the last five decades have impacted timing, duration, thickness of ice cover on Arctic lakes as shown by recent studies. In case shallow tundra lakes, many which are less than 3 m deep, warmer climate conditions could result in thinner covers consequently, a smaller fraction freezing to their bed winter. However, these not yet been comprehensively documented. The analysis 20 yr time series European remote sensing satellite ERS-1/2 synthetic aperture radar (SAR) data numerical lake model were employed determine response (thickness, bed, phenology) North Slope Alaska (NSA) six decades. Given large area covered regional weather related regime shifts lakes. Analysis available SAR from 1991 2011, sub-region NSA near Barrow, shows reduction that freeze late This finding is good agreement with decrease simulated Canadian Lake Ice Model (CLIMo), lower frozen corresponding cover. Observed show trend toward increasing floating fractions greatest change occurring April, when grounded declined 22% (α = 0.01). results indicate 18–22 cm (no-snow 53% snow depth scenarios, α 0.01) during 1991–2011 period 21–38 0.001) 1950 2011. longer (1950–2011) also duration ~24 days consequent later freeze-up dates 5.9 0.1) earlier break-up 17.7–18.6 0.001).