The cold temperatures was an effect of wheather at scandinavia, where a high pressure zone has transported very warm air masses to the arctic circle with temperatures of around 0° Celsius this winter. At Spitzbergen it -1Celsius at present. Normally it is below -20°Celsius in the winter most around -40^Celsius.
The high pressure zone transported the hot air from Europe to the arcticle circle and the cold air masses of the arctic circle to Northamerica leading to extreme low temperatures in the USA and to warm up the arctic region more than ever in history.
Ice in the arctic region will melt faster than expected. New York and Miami will be under water by the end of this century and Wall Street, too...
Arctic sea ice was only lower in 2017, the ice melting is accelerating now.