This story highlights a current research project at the Hubbard Brook Experimental Forest. To read more about research projects at HBEF, visit Current Research page. Check back regularly to learn about new research projects.
An Ice Storm Manipulation Experiment in a Northern Hardwood Forest

 

  Contact Info:
  Lindsey Rustad
USDA Forest Service Northern Research Station
271 Mast Road, Durham, NH 03824
phone: (603) 397-7406
email: lrustad@fs.fed.us
John Campbell
USDA Forest Service Northern Research Station
271 Mast Road, Durham, NH 03824
phone: (603) 868-7643
email: jcampbell@lternet.edu

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) 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 among the most prominent natural disturbances. Despite their influential role in shaping forest ecosystems and the services they provide, knowledge of ice storms and their impacts remains relatively limited. Emerging questions about how climate change may be altering the frequency and severity of ice storms have heightened the need for information. Research at the Hubbard Brook Experimental Forest in New Hampshire is beginning to address some of these topics using a multi-faceted approach that involves field experiments, long-term data, and modeling.

  1998 Ice Storm

What appears to be the first-ever controlled, experimental ice storm manipulation in a forest ecosystem, was conducted 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. The goal of this initial experiment is to evaluate forest damage and effects on carbon sequestration, and plans are underway to build on the success of this approach.

  1998 Ice Storm

The other aspect of this research is an evaluation of how climate change may alter ice storms in the future. Recent emphasis on linkages between climate change and extreme weather events (e.g., heat waves, hurricanes, floods) has raised questions about trends in ice storms over time. As part of this investigation, climate change projections are being used to evaluate potential changes in the probability, duration and extent of freezing rain events. The approach involves identifying the complex climatic conditions associated with past ice storms to make future projections. In total, this research is providing much needed insight on ice storms that will better prepare land managers, industry, policy makers, and the public.

Date Prepared: July 2012