ICE STORMS are an important natural disturbance in forest ecosystems of the "ice belt" that covers a broad area extending from east Texas to New England. These glazing events (defined as 0.25 in. of ice accretion or more) are often perceived as rare occurrences, even though the return interval is as short as 2-5 years in the most ice storm prone northeastern U.S. In this region, ice storms are a major cause of forest disturbance. Despite their influential role in shaping forest ecosystems and the services they provide, knowledge of ice storms and their impacts remains relatively limited, largely because these storms remain hard to predict and scientists don't know when or where they will next occur. A new study at the Hubbard Brook Experimental Forest, NH, is using a suite of tools, including creating artificial ice storms, to study the impacts of these storms on northern hardwood forests. This research will provide the scientific community, land managers and the concerned public greater insight on the impacts of these powerful, frightening, and curiously aesthetic extreme winter weather events on ecosystem dynamics in northern hardwood forests.
This new study follows the first-ever controlled, experimental ice storm manipulation in a forest ecosystem, conducted at Hubbard Brook during February 2011. Water was pumped out of Hubbard Brook and sprayed over the forest canopy during subfreezing conditions to simulate a glaze ice event. The falling water froze on contact, resulting in 0.4 in. of ice accumulation, which is comparable to measurements at Hubbard Brook during the major ice storm of 1998 that affected much of the northeastern US and Canada. This initial experiment provided proof of concept that a controlled ice storm experiment could be done, and evaluated forest damage and effects on carbon sequestration. Read more in Rustad, Lindsey E.; Campbell, John L. 2012. A novel ice storm manipulation experiment in a northern hardwood forest. Canadian Journal of Forest Research. 42: 1810-1818.