Aspen—The man killed in an avalanche on Monday morning near the Markley Hut in the Castle Creek Valley has been identified as Arin Trook. The California native and Stanford graduate was well-known for his love of the outdoors and passion for teaching and sharing his knowledge of environmental science. Trook was in his sixth year as the Education Director at the renowned Aspen Center for Environmental Studies. According to reports from the Pitkin County Sheriff’s Office, Trook and one other person were skiing about 900 yards from the hut when the avalanche occurred. Trook’s companion was able to dig him out and begin CPR right away but to no avail. Authorities with the Colorado Avalanche Information Center say the 400-foot-wide, two-foot deep slide broke loose at just over 11,000 feet in elevation. The avalanche danger was rated as considerable by the center. In addition to his leadership at the ACES, Trook’s environmental science programs were part of the curriculum at Roaring Fork Valley schools from Aspen to Carbondale. Trook is survived by his wife and two children.