Observing Daily Thermal Inversion Cycles of a Mountain Valley in the North Yuba River Watershed
Alaina Ross
School of the Environment
Faculty Supervisor: Alexander Stine
Mountain Meteorology is a complex problem within meteorology due to the steep topography that drives rapid changes in wind speed, direction, temperature. The day-night solar heating cycle creates even further complexity as the uneven heating of the terrain throughout the day creates up-valley and down-valley wind flow regimes. At night, the descending cool air pools in the valley floor, building a vertical thermal inversion where the air temperature at the bottom of the valley is colder than higher up the valley walls. My research focuses on a mountain valley in the North Yuba River watershed in California’s Sierra Nevadas during Summer 2025. We deployed a series of 8 temperature and humidity sensors across a mountain valley in a pattern designed to measure the vertical temperature structure of the air inside the valley throughout the diurnal cycles, including any differences between north-facing and south-facing sidewalls. Each sensor is placed along the sidewalls in 50 meter vertical intervals, logging average temperature and humidity at 10 minute intervals. Using this dataset, I describe fine scale microclimate features at high temporal resolution.