Vapor Pressure Deficit (VPD) is an index that translates into plant stress. The darker the color in these illustrations, the more stressed the vegetation is. The more stressed, the more available to burn. While these levels vary from day to day, overall VPD levels have been on the rise in recent years.
by Dana Skelly These days, there is hardly a wildland firefighter that hasn't said or heard "I've never seen anything like that before." We know that wildfires and the fire environment are more extreme each year. Thinking about a shift from a fire season to a fire year is yesterday's news. Retired Cal Fire Chief…Read more Getting Our Heads Around the New Fire Environment