When ConocoPhillips won federal approval last year to explore for oil in the Alaskan Arctic, environmental groups warned the proposal was rushed through without adequate protections. Last week, an oil rig toppled onto the tundra as it was on its way to drill for that effort, igniting a fire and spilling diesel fuel onto the snow-covered land. Last month, the advocacy group Sovereign Iñupiat for a Living Arctic and two environmental organizations challenged the exploration’s approval in a lawsuit. Rosemary Ahtuangaruak, a former mayor of Nuiqsut and longtime critic of the oil industry, said the warmth can weaken the tundra. “I did not know that I had really strong feelings about what happened to our people until I got into this work,” Simmonds said.