Katie Hirschboeck, a University of Arizona climatology professor and a Roman Catholic, share four main points from Pope Francis' encyclical on the environment.Johanna Willett / Arizona Daily Star 2015
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Readers express opinions on Charleston shooting, gun violence, Pope's climate change encyclical.
Tucsonans escape the heat with road trips, sweet getaways, pool parties.
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Readers sound off on McCain's Iraq war comment, county justice costs.
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Mary Robinson’s talk is presented in conjunction with the Tucson Festival of Books.
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Arizona will be hit harder than most states, a new report says.
The Southwest is heating faster than the rest of the country. Sea levels are rising. Oceans are acidifying. The North Atlantic’s hurricanes are intensifying. Piñon and lodgepole pines are dying.
The U.S. energy advantage is under attack. The shale-gas revolution has spurred billions in new investments and resurrected industries that had left the country.
A University of Arizona researcher is heading a team that wants to learn how climate change affected the evolution of humanlike species.
A Washington, D.C.-based advocacy group has sued the University of Arizona demanding the release of a cache of documents — including two professors’ emails — related to climate change and global warming.
Earlier this year, scientists at the NOAA Mauna Loa Observatory in Hawaii announced a major threshold in the Earth system had been crossed: the concentration of the greenhouse gas carbon dioxide in Earth’s atmosphere has now passed a level not seen in the last 3 million years.