In the past few decades Vermont has been affected in numerous ways due to a changing climate. Some notable changes include a warmer and wetter environment leading to increased flooding events and erosion concerns.
Vermont experienced the warmest winter on record this past year (2024). This has has many unrecognized and unintended consequences on the 90 species of freshwater fish and 21,000 species of invertebrates that live in Vermonts many streams.
Climate change is positively correlated with extreme weather events such as hurricanes. To identify macroinvertebrate response to extreme weather events, researchers studied high flow events following Tropical Storm Irene. It was discovered that macroinvertebrate populations significantly declined following this event (Stamp et al., 2020).
Annual Vermont streamflow is on the rise: a threat to the many macroinvertebrates central towards stream ecosystems.
Another study was conducted to determine the factors that limit the biomass of brook trout, a freshwater fish native to the state, in Northeastern Vermont streams. Of the metrics studied it was found that the the warmest area had no Brook Trout, with temperature exceeding 20 degrees celcius (Kratzer et at., 2013). As this study was done more than a decade ago, waters have only continued to warm and will likely continue to affect the biomass of Brook trout and other sensitive fish species.
Additional stream parameters other than temperature are also being affected by climate change such as nutrient levels. One study assessed how changing water flow alters nitrate and dissolved organic carbon (DOC) transport in northeastern forest streams. High concentrations of both of these solutes can have damaging impacts on water quality and health. Data from the study “suggest that runoff and stream solute loadings will shift seasonally due to hydrological changes that occur with anthropogenic climate forcing” (Sebestyn et al., 2009). This increase in water flow is relevant as this can increase solute fluxes in the streams and therefore the overall health of biological communities.
Information from the 2021 Vermont Climate Assessment regarding Water Resources:
- Since the early 1900s, the average annual precipitation in the state has increased by 7.5 inches (a rate of 1.4 inches per decade).
- Vermont air temperature is expected to increase by 0.5C per decade. Summer surface water temperatures have also increased significantly in the past five decades.
- Temperatures in rivers and streams have also increased. This long-term warming has negative effects on the aquatic biota of the streams.
- Climate change will cause increases in overall precipitation and a rise in streamflow.
- Heavy precipitation influences Vermont water quality by contributing to erosion and nutrient loading. These conditions with the addition of warmer water can lead to blooms of cyanobacteria.
Information from Vermont Climate Assessment a report by the Gund Institute for Ecological Economics and the University of Vermont
Additional ways in which increased flooding will impact Vermont:
- Spread of invasive species.
- Increase in turbidity leading to lower light penetration and lower productivity in streams.
- Increased sedimentation in habitats impacting reproduction of fish.
Potential mitigation and adaptation strategies:
- River corridor protection and management strategies.
- Restoration of channel-contiguous wetlands.
Additional ways in which warming temperatures will affect Vermont:
- Lower capacity to hold dissolved oxygen which is especially critical for cold-water species.
- Possible increase in the duration of warm-season stratification.
- Loss of vernal pools, an essential breeding habitat for many species.
Suggestions for living in potential drought and oncoming dry seasons:
- Diversify farming practices to focus on less water consumption.
- Divert surface water to off-stream reservoirs.
- Promote forest canopy and reduce impervious surfaces in areas known for groundwater recharge.