Allow yourself to think of everything that pops into your mind, without judgment and without emotions of sadness or anger. Accept the thought, allow it to reach its conclusion, and then just let it go.
With the changing of environmental policies, national monuments shrinking and under review, and threats of federal lands being sold for oil drilling and logging, it is more important than ever in these chaotic and ever-changing times that we do everything we can to protect our environment and our national parks.
Try this exercise in your mind. Think about the things that worry or scare you. Consider the worst possible scenario. Now find a solution for that scenario.