Hydropower, wind, and solar together accounted for 24.5 percent of the country's total power generation in 2015. The grid wasn't quite ready for the new technology, though—due to congestion, some of the clean electricity was wasted, and many installed wind turbines sat unused. Bloomberg
A new study finds that the number of mussels along the Gulf of Maine fell by more than 60 percent in the last 40 years. Warming waters, invasive species, and overharvesting have all likely played a role in the die-off. Associated Press
There's plenty to celebrate on the 100th anniversary of the National Park Service, but the park system faces plenty of problems, too—including misbehavior like wildlife harassment, illegal camping, and vandalism from an increasing number of visitors. In July, rangers at the 10 most visited national parks dealt with more than 11,000 incidents. Associated Press
Drifting smoke from Sumatra caused air pollution to hit unhealthy levels in Singapore Friday. Annual forest fires caused by illegal slash-and-burn agriculture have become increasingly intense, and neighboring countries are getting fed up with the government's lack of action against the companies responsible for the blazes. Reuters
The president is quadrupling the size of Hawaii's Papahānaumokuākea Marine National Monument—from 139,797 square miles to 582,578 square miles. The expansion will make the monument the largest marine protected area on the planet! Huffington Post
The Central American country got 100 percent of its electricity using a combination of wind, solar, and geothermal energy. The best part? The streak isn’t over yet! Keep up the good work, C.R.! Inhabitat
An analysis of tree growth, corals, lake sediments, and air from Antarctic ice cores finds evidence of temperature changes in the tropical oceans and the Arctic nearly 200 years ago. Until now, scientists thought climate change caused by human activity began in the 20th century. Reuters
The NPS is celebrating its 100th birthday today. The idea dates back even further, though—Yellowstone, the world’s first national park, was established in 1872. USA Today
Just in time for the National Park Service's centennial, the president has set aside more than 87,500 acres of forest to create Katahdin Woods and Waters National Monument. The region is known for its biodiversity, geology, and abundant recreational opportunities—and the White House says the protected area will help bolster the landscape's resilience to climate change. Portland Press Herald
Climate change has hit previously successful coffee plantations with drought, coffee borer beetles, and other business breakers. So some farmers are switching to cocoa, which is cheaper to grow, sells well on the international market, and can benefit the environment by protecting local water basins and wildlife. Reuters