WASHINGTON — Federal scientists said the winter maximum level of Arctic sea ice was the smallest they have seen, citing extraordinarily warm temperatures.
The National Snow and Ice Data Center said Monday that sea ice spread to a maximum of 5.607 million square miles in 2016. That’s 5,000 square miles less than the old record set in 2015 — a difference slightly smaller than the state of Connecticut.
This winter’s biggest sea ice extent was 431,000 miles less than the 30-year average. That’s the size of Texas and California combined.
Center scientist Julienne Stroeve said winter temperatures over the North Pole were 16 degrees warmer than normal, while it was 4 to 11 degrees warmer than normal elsewhere over the Arctic.
In a separate development, scientists said they may soon be able to predict likelihood of extreme heat in the Eastern United States as much as 50 days in advance, according to a new study.
A team of scientists looking for links between heat waves and the water temperatures in the north central Pacific found a correlation strong enough they said it could be used to make ‘‘skillful prediction’’ of extra warm and dry weather about seven weeks before the temperatures rise.
And they will start trying to forecast Eastern heat waves starting in May, said National Center for Atmospheric Research climate scientist Karen McKinnon, lead author of a study published Monday in Nature Geoscience.
Such warnings can help farmers, utilities, and cities prepare for periods when they’ll need more irrigation, more electrical power generation, and more cooling centers, experts said.