Stretches of calm weather in the mountains might seem harmless, but they can quietly increase avalanche danger over time. And traveling in groups doesn’t always make skiers and snowshoers safer. That’s one of the key takeaways from experts in the Sierra Nevada, where one of the deadliest avalanches in U.S. history recently struck near Lake Tahoe.

The Trump administration is returning to 2012 emission rules, which it says have cut mercury pollution by 90%. Environmentalists say that’s not enough.

Estevan López, New Mexico's water negotiator, said talks resumed March 2, and the upper and lower basin states are using a short-term pitch from Nevada as a starting point.

Record-low snowpack across the Upper Colorado River Basin will likely translate to poor conditions for spring runoff, and could mean emergency action to supplement low water levels in Lake Powell.

Salt lakes in the American West are shrinking — from Utah’s Great Salt Lake to smaller lakes scattered across the Great Basin. In her new book “Salt Lakes: An Unnatural History,” writer Caroline Tracey explores why these unusual landscapes matter, and what their decline reveals about humans’ impact on the environment.

The heat wave comes in the midst of an already challenging winter for the Rocky Mountains, compounding months of warm and dry conditions.

Rusty dust layers can hasten snowmelt and leave farmers, ranchers, and ecosystems with less water during the summer heat. The state’s pure white snow this year is a rare boon that might, or might not, last.

Rain Enhancement Technologies, a private company, is testing a different approach to cloud seeding at a couple of project sites in the Rocky Mountains. The method is known as ionization cloud seeding and doesn't use silver iodide.

Using new data, a team of scientists has assembled one of the first comprehensive analyses of emissions from homes burned in wildfires. What they found is that such pollution is serious, and in some cases can exceed emissions from all other human sources.

Snowpack is often described as the West’s largest natural reservoir, storing water through the winter and slowly releasing it into rivers and reservoirs each spring. But new research suggests the way forests are managed can influence how much of that snow actually becomes part of the water supply.