Peter O'Dowd

Warmer temperatures, drought and disease are putting stress on native tree species in Minnesota. Some trees are dying, but researchers are finding ways to help others adapt to a warmer climate.

Intel planned to open a massive chip plant in Arizona, and President Obama even visited it and called it "an example of an America that's within our reach." But demand for PCs has slowed, and the company is rethinking its next moves.

For the first time in decades, interest rates for jumbo home loans are lower than rates for a typical mortgage. And because of that, the luxury market is the fastest growing sector of home loans. In Phoenix, sales of homes that cost more than $500,000 are up 64 percent.

On a summer night in Phoenix, city dwellers can watch a line of head lamps inch up Piestewa Peak. The mountain rises sharply more than 1,200 feet above the neighborhoods of Central Phoenix. It's the most popular outdoor trek in the city. But in July and August the sun turns deadly there and hikers wait until it's safely below the horizon to begin their ascent. At the top, the view unfolds like magic every time — a desert city of four million people that glows red, white and orange.

Some of Sen. Jeff Flake's constituents in Arizona are still livid over his recent vote against expanded background checks for gun sales. They say the Republican is ignoring their calls for a public meeting.

One of the busiest airports in the country is in the midst of a major upgrade that will bring local restaurants into a space typically reserved for mega-corporate chains. Nearly two dozen Phoenix culinary landmarks have landed space at Sky Harbor. But there is a cost. Rent at the airport is 10 times more expensive in some cases, and some small businesses have gone into a lot of debt to get their foot in the door.

A group of Phoenix charter schools is facing criticism for using a teaching tool based on the work of L. Ron Hubbard, best known for founding the Church of Scientology. The tool has concerned parents in other schools, but the Phoenix schools' leader insists it has nothing to do with the church.

The Chinese solar manufacturer Suntech has announced it is closing down its factory in Goodyear, Ariz. — the only one it has in the United States. The company says recent U.S. tariffs have made it too difficult to maintain its presence here.

With consecutive days of subfreezing temperatures, homeless shelters say they're short on supplies and their budgets are stretched. Meanwhile, farmers are working to fight freezing temperatures that could affect the size and quality of this year's crops.

Democrat Kyrsten Sinema, 36, is a former social worker who spent part of her childhood living in an abandoned gas station. To win her district, made up of almost equal parts Republicans, Democrats and independents, she had to focus on voters in the middle.