Impacts of Climate Change in Vermont

from vtclimate.org/vts-changing-climate

Policy & Community Development: Vermonters value climate change action and generally support current legislation to reduce greenhouse gas emissions 50% by 2028 and source 90% of energy from renewable sources by 2050. Closer to home, every single county in the state of Vermont announced FEMA disaster declarations in response to flooding events in 2011. This vulnerability is exacerbated by the state’s mountainous, rural geography and small communities with limitations existing in transportation routes and communication systems.

Total energy use in Vermont, divided by fuel type. Source: Vermont Comprehensive Energy Plan, 2011.

Energy:  Net energy demand is expected to increase .7% annually through 2030. The increased use of air conditioning will likely outweigh the reduced energy demand for winter heating. An increase in major storm events threatens both Vermont’s energy infrastructure (e.g., energy outages) and supply of fossil fuels from coastal regions. To strengthen Vermont’s energy system, two things must be pursued simultaneously—the increase in use of renewable, local energy sources and gains in energy efficiency and conservation through behavioral change.

Ice jam on the Lewis Creek in Charlotte floods the Lewis Creek Road and Spear Street Extension and adjacent residence during a January 2010 thaw. Photo credit: Kristen Underwood

Water resources: Vermont’s waters and snowpack are thawing earlier as spring temperatures arrive earlier. Annual average stream flows are increasing as precipitation increases. There is an 80% increase in the likelihood of high stream flows (and flooding) in coming decades, particularly in the winter months as snow shifts to rain or freezing rain. In contrast to other New England states, Vermont rivers have sustained flow over recent decades in summer months, however, climate projections show increased potential for short-term dry spells this century.

Forests: The lengthened growing season will increase the geographic range suitable for certain Vermont tree species like oak, hickory, and red maple, but decrease suitable range for cold-tolerant species like spruce and fir. The early growing season results in earlier bud burst and flowering periods that make certain trees more susceptible to pests and pathogens. Wetter winters and extended summer dry spells will place more stress on important species such as sugar maple and red spruce that have already experienced periods of decline.

Hemlock woolly adelgid (HWA; Adelges tsugae), a scale-like insect introduced from Japan, has attacked and caused widespread mortality of eastern hemlock trees (Tsuga canadensis) in North America. Milder winters will allow more infestation of HWA in Vermont. HWA kills trees within 6 years.

As the time between last and first frost lengthens, so does the growing season. Source: VCA 2014, NWS 2014

Agriculture: An extended growing season will increase overall crop productivity and create new crop opportunities. Increasing CO₂ in the atmosphere may enhance crop growth to some extent. Conversely, these conditions can increase weed growth, disease outbreaks, and pest infestations. For Vermont livestock operations, enhanced growing conditions could increase pasture and forage productivity although this may be offset by small decreases in livestock productivity due to summer heat stress and increasing costs of production inputs (e.g., feed, energy).

Vermont visitor spending (US$ Millions; left) and Person Trips (Millions; right) in 2011(Chmura Economics and Analytics 2011).

Recreation and Tourism: Over the next 25 years, snowfall in mountainous areas may increase with increasing winter precipitation (a climate change “sweet spot”), bringing a positive impact on winter-related recreation and tourism. Within 30-40 years, most winter precipitation will fall as rain and result in shorter-lasting snowpack and snowfall. There are opportunities to compensate for winter losses—1) more tourists are expected as the summer season lengthens and states to the south experience increased temperatures combined with higher humidity; and 2) fall recreational and tourism opportunities will lengthen with extended warmer temperatures.