Extreme high temperatures in the summer stress forests and wildlife. These days increase water loss from transpiration and can damage trees. Additionally, extreme high temperature days increase the risk and severity of wildfires.
To measure extreme high temperature days the FHI looks at temperature measurements from a combination of on-the-ground sensors and satellite data. We count the number of days each summer that exceed 90th percentile in a normal summer about 10 days will meet this criteria.
The number of extreme high temperature days was near average for this watershed.
Forests have evolved with periodic extreme high temperature days. Similar to humans they can withstand these conditions for limited amount of time but persistent extreme heat will begin impacting forests. Forests at the lower end of their elevational range and on south facing slopes are the first to be impacted. Under more extreme conditions high elevation forests and forests on north facing slopes will also be impacted.
Climate change is increasing temperatures across the country. While the average temperature is almost sure to increase, predictions about temperature extremes are more uncertain. In addition to impacting forests extreme temperatures can impact humans. Each year more people in the US die from extreme temperatures than any other natural disaster.