Declining rock movement at Racetrack Playa, Death Valley National Park: An indicator of climate change?

• Summarizes documented trail formation events from the literature
• Uses Monte Carlo formalism to establish significant decline in rate of events
• Nearby meteorological records show decline in winds and in ice formation conditions

We have inspected Racetrack Playa at Death Valley over the last 7 years and have not observed major episodes of rock movement and trail generation. We compare this null observation with the literature record of the rock movement using a Monte Carlo method and find 4-to-1 odds that the rock movement probability has systematically declined. This statistically significant drop in movement rate may indicate a change in the probability of the required conditions for movement: we note decline in the occurrence of strong winds and in ice-forming cold in nearby weather records. Rock movement and trail formation may serve as an indicator of climate change.