The sounding rocket released bright puffs of tri-methyl aluminum, which scientists track from the ground to study winds near the lower boundary of space. The streak on the bottom right is formed by chemicals that have been moved and distorted by winds and turbulence.

Photo Courtesy Carl Andersen

On a clear, cold night two winters ago in Fort Yukon, Carl Andersen watched a rocket he helped design pierce the upper atmosphere. He and three other scientists shot pictures as the rocket ejected bright puffs of chemicals in an inverted V formation more than 60 miles up.

“They were the brightest things in the sky,” Andersen said from his office at the University of Alaska Fairbanks.

The healthy April snowpack in interior Alaska.

Photo by Ned Rozell.

An April snowstorm whirling outside my window today seems to be announcing the postponement of spring. As I sit here watching the show, it makes me think back to the shortest summer ever.

In 1992, it snowed more than 9 inches on May 12th. A string of 70-degree days that followed ate that up in a hurry, but the snow returned in early fall. By September 13th, more than one foot of snow cushioned the ground, and leafed birch trees arced under the weight of ice crystals. Twenty-one years later, some trees still bow to that memory.

Lightning strikes the hills northwest of the Yukon River.

Photo by Ned Rozell.

Forty years ago, an Army helicopter pilot flying over a tundra plateau saw a group of caribou. Thinking something looked weird, he circled for a closer look. The animals, dozens of them, were dead.

The pilot reported what he saw to the Alaska Department of Fish and Game. The caribou, 48 adults and five calves, were lying in a group. The way their carcasses rested showed no signs that the animals had been running from a predator.

Fairbanks, seen here at minus 40 during January 2012, is one of many Alaska places that — unlike most of the world — leaned to the cold side during the first decade of the 2000s.

Photo by Ned Rozell.

This just in: 2012 was the coldest year of the new century in Fairbanks, and the second coldest here in the last 40 years.

Fairbanks isn’t the only chilly place in Alaska. Average temperatures at 19 of 20 long-term National Weather Service stations displayed a cooling trend from 2000 to 2010, according a recent study written up by Gerd Wendler, Blake Moore and Lian Chen of the Alaska Climate Research Center.

Duane Froese of the University of Alberta in forest of stumps smothered by the White River Ash around the year 843 AD. Froese is pictured in the Yukon Territory close to the Alaska border and Natazhat Glacier in an area downwind of the great White River eruptions, which spewed from somewhere near Alaska’s Mount Churchill.

Photo courtesy Duane Froese.

The White River Ash, blasted from giant eruptions somewhere in today’s Wrangell-St. Elias Mountains, drifted as far away as Ireland and Germany, said experts who attended the December 2012 Fall Meeting of the American Geophysical Union, held in San Francisco.