Vermont Forest Indicators Dashboard


Score for 2017:
Long-Term Trend:
Scores are 
While mild, short-term droughts are not an uncommon event in Vermont, with higher temperatures resulting from continued climate change, we may see more severe or longer duration droughts. Lack of water, particularly during the growing season, can result in short-term changes in our forests, for example, a tree will halt photosynthesis and growth until there is sufficient water. But droughts can also result in more serious consequences to forests, like lack of a viable seed crop or large die offs of vulnerable species, locations, or age classes. Seedlings are particularly vulnerable to drought due to their shallow root systems. Further, droughts can increase the chance of forest fire -- a condition to which many of our tree species are not adapted. Insect pest outbreaks can also be more destructive when they occur with or following drought. Here, we used an pre-computed index of drought called the Standardized Precipitation Evapotranspiration Index (SPEI), which incorporates both rainfall, temperature, and plant water requirements12. We set the target for the dataset as the long-term mean with the understanding that droughts are a natural phenomenon, but changes in the frequency or duration of seasonal droughts could pose serious threats to forests as we know them. Annual scores were computed as the deviation from the data target, scaled from 0-1.
1Vicente-Serrano S.M., Beguería S., López-Moreno J.I., 2010: A Multi-scalar drought index sensitive to global warming: The Standardized Precipitation Evapotranspiration Index – SPEI. Journal of Climate 23(7), 1696-1718, DOI: 10.1175/2009JCLI2909.1.--
2Vicente-Serrano S.M., Beguería S., López-Moreno J.I., Angulo M., El Kenawy A. (2010) A global 0.5° gridded dataset (1901-2006) of a multiscalar drought index considering the joint effects of precipitation and temperature. Journal of Hydrometeorology 11(4), 1033-1043, DOI: 10.1175/2010JHM1224.1.--
FEMC Archive Resources
Dataset: Vermont Growing Season SPEI