Anomalous Snow Density Values in the North and South Pole

Dear everyone,

I noticed that the snow density values of Antarctica and Arctic are almost 300kg / m ³。

How to explain this phenomenon

I think these measurements are most likely erroneous

as snow densities typically range between 50 and 550 kg /m ³ (Fierz et al., 2009)

The picture is attached

Thank you.