Climate Research

AMC climate research has evolved from decades of air quality research and builds on long-term monitoring across the region, including the White Mountains, Maine, and the Northeast. In the White Mountains, we study alpine plant phenology (seasonal timing of plant life cycles) and coordinate with Mount Washington Observatory to evaluate long-term records of weather and climate on the Northeast’s highest peak. In Maine, we study mountain ponds that record environmental changes like acid rain, recovery from acidification, and shifting climate. In the Northeast region, we assess how changing winter conditions affect people, natural resources, and recreational opportunities.

Changing Winters

AMC’s region is warming faster and experiencing more extreme events—like heavy precipitation and intense storms—than the rest of the nation. In particular, our winters are changing dramatically. We studied 100 years of weather data across the region, along with AMC’s own Pinkham Notch long-term monitoring site and the results are clear:

• We are losing the cold. Even at mid- and high- elevations in the White Mountains, winter and spring are warming faster than other seasons—though all seasons are indeed warming.
• We are losing the snow. With 21 fewer days of snow cover at Pinkham Notch most of that shift is happening at the end of winter where snowmelt is shifting earlier by nearly 2 weeks.
• And in the Northeast, winters have become 3 weeks shorter over the past 100 years. But even within winter, we are seeing dramatic back-and-forth shifts in weather conditions, like the record-breaking warmups followed by a return to more normal cold conditions. These “winter weather whiplash” events can set us up for major flooding, can harm crops and vegetation, and cause problems for winter recreation.

Mountain Climate and Air Quality

The science underpinning our understanding of how, when, and where climate is changing relies, in large part, on long-term monitoring. AMC has been tracking ozone, acid rain, and haze in the Northeast mountains for decades. The good news is the Clean Air Act is working, reducing emissions and resulting in less air pollution in our region. We need to retain the strength of this important policy tool rather than relax the rules and slip backwards, allowing more pollution. There are still impacts from more than half a century of acid rain—despite enacting policies that have reduced acid rain, ecosystem recovery lags behind. And the same smokestacks and tailpipes that emit nitrogen, sulfur, organic toxins, and heavy metals also emit carbon dioxide—the major cause of climate change.

Vegetation Shifts and Phenology

AMC has monitored and mapped alpine and montane plants communities in the Northeast to document baseline conditions and detect potential changes from climate and seasonality shifts. By tracking the timing of plants’ life history events, like flowering times and leaf-out, we can evaluate how changing climate affects AMC’s priority landscapes. Our work used modeling and found that three alpine plants are flowering earlier since the 1930s, but only by one to two days. We are continuing to build on that study by collecting additional alpine phenology observation in part by using community science. Northeast Alpine Flower Watch volunteers make plant phenology observations with the iNaturalist app in Northeast Mountains.