New Hampshire Climate Impacts and Costs

The report details how climate change is increasing the frequency and severity of extreme weather in New Hampshire, leading to significant infrastructure damage and economic losses. It highlights a 12% increase in annual precipitation since 1901, a 2°F rise in average annual temperature since 1971, and a 7-inch rise in sea level since 1950. The document outlines necessary adaptation costs across public health, infrastructure, and local planning to mitigate risks to the state's winter recreation industry, coastal properties, and public school systems.

• New Hampshire has seen a significant increase in precipitation and extreme storm events. Annual precipitation rose by 12% when comparing 1901-1960 to 1991-2020, and the number of days with over 5 inches of rain has doubled over the last 64 years. Extreme precipitation events in the northeastern United States increased by over 50% between 1996-2014 compared to 1901-1995.
• Rising temperatures are impacting New Hampshire's economy and public health. The average annual temperature has increased by approximately 2°F since 1971, contributing to a decrease in snowpack—over 90% at one Lake Winnipesaukee watershed station—and shorter winters. This threatens the ski industry, which generates about $500 million annually and supports 10,000 jobs, and has already seen the loss of 172 ski areas.
• Extreme heat is increasing, affecting education and health. The number of extreme heat days (heat index above 90°F) has doubled since 1980, rising from 8 to 15 days per year. This has led to school closures in Manchester and other parts of the state due to lack of air conditioning, and an increase in vector-borne illnesses like Lyme disease.
• Sea level rise poses a substantial threat to New Hampshire's 13-mile coastline. Sea levels have risen 7 inches since 1950 and may rise up to 5 feet by 2100. Approximately 4,500 people and 1,900 homes valued at around $622 million are at risk. Vulnerable infrastructure in Seabrook includes a nuclear power station, wastewater treatment plant, and schools.
• The state faces significant infrastructure adaptation costs to manage flooding and heat. Necessary projects include floodproofing municipal buildings, elevating roads and bridges above base flood elevation, installing cooling centers, and upgrading school air conditioning. The report also notes that current infrastructure was not designed for current or projected precipitation patterns.

APA

Center for Climate Integrity (2025). New Hampshire Climate Impacts and Costs. https://climateintegrity.org/uploads/media/CCI_New_Hampshire_Impacts_Costs_2024.pdf

Chicago

Center for Climate Integrity. New Hampshire Climate Impacts and Costs. 2025. https://climateintegrity.org/uploads/media/CCI_New_Hampshire_Impacts_Costs_2024.pdf.

Wikipedia

{{cite report |author=Center for Climate Integrity |title=New Hampshire Climate Impacts and Costs |date=2025 |url=https://climateintegrity.org/uploads/media/CCI_New_Hampshire_Impacts_Costs_2024.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{centerforclimateintegrity2025new, author = {{Center for Climate Integrity}}, title = {{New Hampshire Climate Impacts and Costs}}, institution = {Center for Climate Integrity}, year = {2025}, url = {https://climateintegrity.org/uploads/media/CCI_New_Hampshire_Impacts_Costs_2024.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }