The rapid melting of sea ice in some parts of the Arctic could unleash phenomena that result in extraordinary North American cold spells, scientists have found — including the one that paralyzed Texas in February , causing an estimated $90 billion in losses. A study led by Judah Cohen, director of seasonal forecasting at Atmospheric and Environmental Research, a part of risk analytics firm Verisk, is the first to find a connection between the Arctic warming and extreme winter weather events. The paper, published Thursday in Science , combines observational data over the past four decades with new climate models. Researchers analyzed the role of the polar vortex, a low-pressure system near the North Pole that helps keep cold air trapped in the Arctic. When some other event weakens it or when it’s disrupted, cold spills down toward southern latitudes. “Melting sea ice across northwestern Eurasia, coupled with increased […]