Estimating lake ice thickness in Central Ontario

Abstract

Lakes are a key geographical feature in Canada and have an impact on the regional climate. In the winter, they are important for recreational activities such as snowmobiling and ice fishing and act as part of an important supply route for northern communities. The ability to accurately report lake ice characteristics such as thickness is vital, however, it is underreported in Canada and there is a lack of lake ice thickness records for temperate latitude areas such as Central Ontario. Here, we evaluate the application of previously developed temperature models and RADARSAT-2 for estimating lake ice thickness in Central Ontario and provide insight into the regions long term ice thickness variability. The ALS Environmental Science Shallow Water Ice Profiler (SWIP) was used for validation of both temperature and radar-based models. Results indicate that the traditional approach that uses temperatures to predict ice thickness during ice growth has low RMSE values of 2.3 cm and correlations of greater than 0.9. For ice decay, similar low RMSE values of 2.1 cm and high correlations of 0.97 were found. Using RADARSAT-2 to estimate ice thickness results in R2 values of 0.6 (p < 0.01) but high RMSE values of 11.7 cm. Uncertainty in the RADARSAT-2 approach may be linked to unexplored questions about scattering mechanisms and the interaction of radar signal with mid-latitude lake ice. The application of optimized temperature models to a long-term temperature record revealed a thinning of ice cover by 0.81 cm per decade.

Ice processes on medium‐sized north‐temperate lakes

“…April 2017 was 4.3°C warmer than April 2016 and had ~7 cm more ice, yet despite this, WCI was only 3 days different between the years. No SWIP data were available for the 2015–2016 season; however, Murfitt, Brown, and Howell () estimate maximum 2015–2016 ice thickness for MacDonald Lake to be 44.7 cm, based on accumulated freezing degree days, which is close to the final measured thickness of 41.3 cm on March 4. Using the maximum measured thickness for the 2015–2016 season and duration to WCI returns a (linear) melt rate of 0.8 cm day −1 .…”

“…Even with a slightly thicker ice cover, warmer April temperatures in 2017 resulted in a more rapid melt rate of 1.8 cm day −1 (near‐linear melt seen in the SWIP data after the brief regrowth period March 15–26). The ice thickness models for MacDonald Lake, developed by Murfitt et al (), were based on accumulated freezing and thawing degree days, and a combined model for the full seasonal evolution of the ice cover was in strong agreement with the SWIP ice thickness measurements (index of agreement = 0.93), clearly highlighting the strong connection between air temperature and ice formation/decay. The nearby Haliburton weather station data were used as input to the degree day models for the last nine ice seasons (2008–2017).…”

“…The nearby Haliburton weather station data were used as input to the degree day models for the last nine ice seasons (2008–2017). Melt rates in terms of cm of melt per accumulated thawing degree days (ATDDs) were determined from the ice thickness decay model, which show melt rates of −0.50 cm/ATDD in 2016 and −0.53 cm/ATDD in 2017 (Murfitt et al, ). These rates indicate that more melt occurred per degree day in 2017 than 2016, which was likely a result of increased solar radiation received during April versus March, as melt onset commenced earlier in 2016.…”

Remote Sensing of Environmental Changes in Cold Regions: Methods, Achievements and Challenges

“…Their study obtained ice thickness estimates with RMSE of 33 cm when compared to in-situ measurements obtained at GSL. Murfitt et al [90] evaluated RADARSAT-2 data for estimating lake ice thickness in Central Ontario, Canada. They reported RMSE values of 11.7 cm and attributed the uncertainty to unexplored questions about scattering mechanisms and the interaction of the radar signal with lake ice having complex structure within the ice layer and at the ice-water interface.…”

The ice regime of Lake Ostrzyckie (Kashubian Lakeland, northern Poland)

“…Gradually increasing air temperature is a good indicator of ongoing changes in climate, it also visibly affects ice phenomena observed on lakes located in the temperate climate zone, including water bodies in the Kashubian Lakeland. Changes in air temperature may also affect economic and leisure activities taking place in areas dependent on ice cover (Murfitt et al 2018). Climate change is reflected by changes in the ice regimes of numerous lakes in other regions of Poland (Borowiak and Barańczuk 2004;Marszelewski and Skowron 2009;Barańczuk et al 2017;Ptak et al 2019).…”