Assessing Coastal Forest Impacts and Resource Management Implications following Hurricane Sandy
Science Center Objects
Tropical storms and hurricanes wreak havoc with coastal forests where damage can vary with wind speed and approach from isolated treefalls to wide-area blowdowns of whole forests.
The Science Issue and Relevance: Tropical storms and hurricanes wreak havoc with coastal forests where damage can vary with wind speed and approach from isolated treefalls to wide-area blowdowns of whole forests. More often forest damage is somewhat diffuse and distributed over a large area given typical storm expanse and waning wind speeds with distance away from the eye of the storm. The direction of windfall also differs with site location relative to storm path whether on the backside or foreside of the storm track. Department of the Interior (DOI) land managers require information on the full extent of forest damage to clear roads and trails and to plan salvage operations, research or restoration efforts. Aerial surveys are necessary to capture the whole landscape perspective and a proper assessment of spatial aspects of forest impact, whether light or heavy, in guiding decisions about recovery, research, and restoration.
Methodology for Addressing the Issue: Aerial videography was filmed from low-altitude overflights by seaplane above primary study sites where forest damage was most extensive. Associated ground surveys were conducted to georeference each treefall along with notation of species, size and compass azimuth of treefall orientation. Single frame analysis of video tracks and field transect measurements were used to classify degree of forest damage and angle of treefall to estimate the spatial extent of damage and to elucidate causal relations with peak winds and storm surge inundation. Overlay maps were created to associate treefall field data with aerial image determinations to validate and relate observations from both observation sets.
Future Steps: The project will produce an understanding of the interaction of storm surge tides on soil liquefaction and wind force and direction that can be applied in explicit landscape simulation models to improve predictive modeling of future ecosystem consequences under climate change and increasing hurricane frequency and intensity.