Returning to campus from Spring Break, some students did not pack away their flip-flops, suntan lotion, and shorts. As temperatures were unseasonably high from the Midwest to the Northeast, students in Cambridge enjoyed 70-degree Fahrenheit weather—a remarkable 30 degrees above the typical monthly average.

Highs of 77 degrees Fahrenheit on Wednesday and 75 degrees on Friday neared previous record highs, while Thursday’s 78 degrees temperature broke the previous record.

“It’s a beautiful day to be outside,” Charlotte M. J. Friedrichs, a visiting student from Germany, said on Friday. “This is my second semester here, and the weather has always been the opposite of what I expected.”

Many students spent time in sunbathing, studying, or eating meals outside on the campus lawns.

“There is an overall mood of happiness on campus, when the weather is nice,” said Peter M. Riley ’14, who had his lunch outside the Science Center last Friday.

According to Earth and Planetary Sciences professor Peter J. Huybers, March temperatures have risen for a combination of factors.

“March temperatures have steadily increased due to an increase in greenhouse gases—a warmer climate and maybe a more veritable climate has led to the likelihood of higher temperatures,” Huybers said. “But these temperature extremes go beyond what we would experience from that.”

Huybers added that this additional extremity is due to an abnormal variation in the jet stream, which swung further down south than usual.

“It reached down to latitudes of the Gulf of Mexico and sent hot air from south to north,” Huybers said.

This hot air from the South had a significant impact on temperatures in the Northeast as well as in the Midwest and Great Lakes region, Huybers said. In Burlington, Vermont, the temperature hit 81 degrees on Wednesday, breaking the previous record of 68 degrees. The same day Bangor, Maine, reached 83 degrees, breaking the city’s previous record high of 64 degrees. In Marquette, Michigan, the temperature reached 81 degrees, leaping past the previous record of 49 degrees.

“The Gulf [jet] stream set up and moved very slowly,” Huybers said. “And because of that slow movement there was more time to direct hot air from south to north.”

This aberration led to day-after-day warm weather in Cambridge—and in other cities like Chicago, where the temperature reached 80 degrees on eight out of nine days.

According to Huybers, these variations in the jet stream are common at this time of year, but overall climate change has combined with abnormally large variations to produce record-breaking temperatures.

“To put it succinctly,” Huybers said, “climate change is loading the dice, and now we are tending to get higher numbers.”