The crown jewel of Colorado, Rocky Mountain National Park, is struggling under the impacts of climate change. "From bark beetle infestations to changes to wildlife habitat, Rocky Mountain National Park alone has undergone changes due in part to rising temperatures," reads a statement by U.S. Senator Mark Udall, a Colorado Democrat, who will join Senator John McCain, an Arizona Republican, today for a field hearing at the Estes Park Town Hall (170 MacGregor Avenue) to discuss climate issues (via The Colorado Independent). Udall, who is chairman of the Energy and Natural Resources Subcommittee on National Parks, joined McCain (pictured) yesterday morning on 9News' Your Show to highlight the problems. "I think the evidence is overwhelming that climate change is taking place, and it is damaging our national parks," McCain says. The hearing will include several experts and officials, including Alice Madden, Colorado's climate change coordinator. Prior to the hearing, the senators plan to tour park areas affected by climate change or pollution, writes the Denver Business Journal. The RMNP and 15 other national parks around the country are grappling with increased ammonium deposits from declining air quality, which could have ill effects on aquatic plants and animals, notes the Fort Collins Coloradoan.