Northeast US States NIACS Unit Street trees Residential Multi-family residential Commercial/ Industrial Park Cemetery Golf course Agriculture Vacant Institutional Utility Water Transportation Other Crop Range Pasture Agricultural facilities and infrastructure Agricultural tree plantations Associated agricultural lands Non-agricultural rural developed land Non-agricultural designated protected area Riparian Infrastructure Wetland State Connecticut Delaware Maine Maryland Massachusetts New Hampshire New Jersey New York Pennsylvania Rhode Island Vermont West Virginia Vulnerability Assessment National Climate Assessment (2018) - Northeast Climate Impact Statements Temperatures in the Northeast are projected to increase between 3°F to 10°F by the end of the century. By mid-century, the southern portion of the Northeast will experience 18-21 more days exceeding 95°F per year. By mid-century, the northern Northeast region will experience fewer days below 10°F, perhaps as much as 21 fewer days per year. Over this century, winter and spring seasons in the Northeast will be wetter, with 5-20% more precipitation occurring during these seasons. The frequency of heavy downpours is projected to continue to increase across the Northeast. The winter season will be shorter and milder, with less precipitation falling as snow and reduced snow cover and depth. By mid-century, spring stream flow is expected arrive 4 to 9 days earlier, and the probability of high-flow events may increase as much as 80% for some areas of the Northeast. The growing season in the Northeast is expected to increase by at least 19 days or more by the end of the century, due to fewer days with a minimum temperatures below 32°F Systems that are limited to particular environments will have less opportunity to migrate in response to climate change. Southern or temperate tree species in the Northeast will be favored by climate change. Northeast forest productivity may increase due to climate change during this century. Timing of critical biological events, such as spring bud burst, emergence from overwintering, and the start of migrations, has shifted in the Northeast. Many invasive plant species, insect pests, and pathogens in the Northeast will increase or become more damaging due to climate change. North Atlantic hurricanes will increase in frequency, and intensity during 21st century. As sea levels rise, the Chesapeake Bay region is expected to experience an increase in coastal flooding and inundation of estuarine wetlands. Sea levels along the Northeast Atlantic coast are expected to rise by 7 to 23 inches by the end of the century. Low-diversity systems are at greater risk from climate change. Species in fragmented landscapes will have less opportunity to migrate in response to climate change. Systems that are more tolerant of disturbance have less risk of declining on the landscape The urban heat island effect can exacerbate the effects of increasing temperatures. Impervious cover can exacerbate the effects of increased heavy precipitation events in urban areas. Forest composition will change across the landscape Tree regeneration and recruitment will change Forest productivity will increase during the next several decades in the absence of significant stressors Surface water temperatures are expected to rise due to warming air temperatures Inland lakes are warming, and continued warming will decrease seasonal mixing of stratified lakes and reduce available dissolved oxygen Seasonal variation in soil moisture and altered precipitation may influence the magnitude and duration of flood events. Low streamflow events may become more frequent and deliver lower water volumes
