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Tropical cyclones are expected to intensify under a warming climate, with uncertain effects on tropical forest ecosystems. One key challenge to predicting how more intense storms will influence these ecosystems is to attribute hurricane impacts specifically to storm meteorological characteristics rather than differences in forest characteristics. Here we compare tree damage data collected in the same forest in Puerto Rico after Hurricanes Hugo (1989, category 3), Georges (1998, category 3), and María (2017, category 4). María killed twice as many trees as Hugo, and for all but two species, broke 2- to 12-fold more stems than the other two storms. Species with low density wood were particularly vulnerable to uprooting and breakage. Extensive tree inventories and a wind exposure model allow us to attribute these differences in impacts to storm meteorology. A better understanding of risk factors associated with tree species susceptibility to severe storms is key to predicting the future of forest ecosystems under climate warming.
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Analytical fragility curves for trees subject to ice loading in a changing climate
Campos, Richard & Harvey, P. & Hou, Guangyang. (2023). Analytical fragility curves for trees subject to ice loading in a changing climate. 10.1080/23789689.2023.2202962. Recent severe ice storms across the United States severely damaged trees resulting in extensive electrical power outages. Furthermore, trees and branches can fall on nearby roads, blocking traffic flow and reducing the safety of drivers. In this study, trees subjected to ice loads were analyzed using the finite element method and Monte Carlo simulation to develop analytical fragility curves. Two-dimensional, fractal trees were constructed with randomly generated geometric and mechanical parameters for four deciduous tree species: Acer saccharum, Tilia americana, Fagus grandifolia, and Quercus alba. Two load case scenarios were considered – with and without the effects of leaves – which were then subjected to varying ice accumulation thicknesses. The resulting fragility curves suggest that leaves have a substantial impact on tree branch damage under ice loads, which is significant because of the increase in unseasonably early ice storms due to climate change.
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- Award ID(s):
- 1946093
- PAR ID:
- 10493979
- Publisher / Repository:
- www.tandfonline.com/journals/tsri2
- Date Published:
- Journal Name:
- Sustainable and Resilient Infrastructure
- Volume:
- 8
- Issue:
- 6
- ISSN:
- 2378-9689
- Page Range / eLocation ID:
- 555 to 571
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1080/23789689.2023.2202962
