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This dataset is part of a project studying the effects of wildfire on the Illilouette Creek Basin, a watershed within Yosemite National Park. Three temporary weather stations were installed under distinct types of vegetation cover. Each station measures air temperature, relative humidity, rainfall (the rain gage is not heated, so only the portion of snowfall that melts within the gage is measured), wind speed and direction, solar radiation, and both soil moisture and temperature at three depths. These measurements are recorded every 10 minutes, beginning in the summer of 2015 through June 2021. Snow depths and percent cover were estimated from time lapse imagery up to four times per day, and field measurements of snow depth and density were conducted up to two times each winter. The west-facing hillside where these stations are located most recently burned in 2004 and 2017 (Empire Fire). Photos are included of the stations both before and after the Empire Fire. For descriptions of the data format and units, see the included WeatherStnMetadata.xlsx file. 

Abstract Reducing the risk of large, severe wildfires while also increasing the security of mountain water supplies and enhancing biodiversity are urgent priorities in western US forests. After a century of fire suppression, Yosemite and Sequoia-Kings Canyon National Parks located in California’s Sierra Nevada initiated programs to manage wildfires and these areas present a rare opportunity to study the effects of restored fire regimes. Forest cover decreased during the managed wildfire period and meadow and shrubland cover increased, especially in Yosemite’s Illilouette Creek basin that experienced a 20% reduction in forest area. These areas now support greater pyrodiversity and consequently greater landscape and species diversity. Soil moisture increased and drought-induced tree mortality decreased, especially in Illilouette where wildfires have been allowed to burn more freely resulting in a 30% increase in summer soil moisture. Modeling suggests that the ecohydrological co-benefits of restoring fire regimes are robust to the projected climatic warming. Support will be needed from the highest levels of government and the public to maintain existing programs and expand them to other forested areas. 

Abstract The complexity of forest structures plays a crucial role in regulating forest ecosystem functions and strongly influences biodiversity. Yet, knowledge of the global patterns and determinants of forest structural complexity remains scarce. Using a stand structural complexity index based on terrestrial laser scanning, we quantify the structural complexity of boreal, temperate, subtropical and tropical primary forests. We find that the global variation of forest structural complexity is largely explained by annual precipitation and precipitation seasonality (R² = 0.89). Using the structural complexity of primary forests as benchmark, we model the potential structural complexity across biomes and present a global map of the potential structural complexity of the earth´s forest ecoregions. Our analyses reveal distinct latitudinal patterns of forest structure and show that hotspots of high structural complexity coincide with hotspots of plant diversity. Considering the mechanistic underpinnings of forest structural complexity, our results suggest spatially contrasting changes of forest structure with climate change within and across biomes.