In honor of Earth Day on April 22, here are five ways Nat Geo explorers are protecting the planet! Katey Walter Anthony 1) Global warming is causing permafrost in the Arctic to thaw, which releases methane into the atmosphere, which in turn contributes to global warming. Explorer Katey Walter Anthony is researching this dangerous cycle and hoping to harness methane as a renewable energy source. … Continue reading Every Day is Earth Day for Our Explorers