Hidden underneath the hilly grasslands studded with ocotillos and mesquite trees in southeastern Arizona lies a world shrouded in perpetual darkness: Kartchner Caverns, a limestone cave system renowned for its untouched cave formations, sculpted over millennia by groundwater dissolving the bedrock and carving out underground rooms, and passages that attract tourists from all over the world.
As the world starts feeling the effects of increasing atmospheric carbon dioxide and consequent global temperature rise, researchers are looking for a Plan B to mitigate climate change.
You approach the Tucson mountain retreat by a 500-foot path through saguaro cactus and palo verde. The squat, earth-colored structure looks a little bunker-like at first, but from closer up the walls turn out to be not concrete but rammed earth, with a rich layering of warm colors.
Deserts are stark environments where extreme heat, cold, and lack of moisture mean only the hardiest of species can survive there.
Big solar was the biggest driver in the record-breaking U.S. solar gains made last year, with utility-scale plants accounting for more than half – 1,752 megawatts – of the 3,313 MW of newly installed capacity.