At least 30 people have died and millions of Americans are still without power as the polar vortex that’s brought record snowfall and dramatic sub-zero temperatures this week hindered recovery efforts. While states including Oklahoma, Louisiana, Mississippi and Arkansas are among those struggling to deal with the icy chill, the worst hit has been Texas where almost 2 million people are still without power. The state’s deregulated power market – the only one in the country – has been blamed for the widespread blackouts. Some weather types attribute the unusual cold snap to climate change and warn that Arctic warming will push freezing weather events further south in coming years. The coldest place in the US last night was in Alaska with -62C, but that doesn’t count… Next coldest was Rogers Pass in Montana (on the Canadian border) with -56.7C…