Changes to forest tree species composition include shifts from the current maple-dominated community composition to a community dominated by species better adapted to warmer climate, such as pines and hardwoods. Additional risk from more frequent and severe forest wildfires will be increased by hotter, drier climate. An overall loss of forested lands in Connecticut is estimated 30%-60% by the end of the current century.
Loss of wildlife and habitat as a result of climate changes and shifting geographical range threatens the $833 million annually received by the state in the form of hunting, fishing, and wildlife viewing tourism.
Agricultural crop yield is heavily reliant on temperature, moisture and day-to-day weather and are especially vulnerable to climate change. Major regional shifts will be necessary to continue current production and ensure a high quality of food commodities. It is predicted that crop production will shift northward, making adaptation for farmers difficult. Initial increases in forest and crop growth may be observed in response to elevated levels of atmospheric CO2, but within a short amount of time plants will begin to be adversely affected by high amounts of ground-level ozone. Ground-level ozone is damaging to trees and plants. Milder winters will increase the likelihood the weeds, pests, and pathogens previously unable to persist in the climate of the Northeast will invade, increasing the cost of pest control as well as costly damages. As winters become milder, the number of freezing days required for crops such as apples and Concord grapes will no longer be met in the next several decades in either high or low emission scenarios. Other fruits at risk are blueberries, raspberries and pears. Overall crop yield for hay and silage is expected to decrease as much as 40% by the year 2100, with the number of acres farmed unchanged, and a decrease in the average farm income of approximately 50%.
Livestock production is expected to decline as the cost of feed and ventilation for indoor animals increases, and as limitations to crop production limit forage resources. Increased temperatures may also cause direct stress to animals, causing decreases in growth and a projected 20% or more decrease in milk production.
An increase in the amount of precipitation received during downpours is expected to increase flooding, increasing damages to infrastructure and causing human health problems, especially in cities where heavy rains can overwhelm drainage systems and water treatment facilities, increasing the likelihood of waterborne diseases and associated heath care costs.
Increases in sea level are projected to cause additional economic damage to property values, including loss of property, destruction of property, and erosion of the coastline by increasing flooding and storm surge. What has been considered a once-per-century flood in New London and Groton is projected to occur every 17 years under high-emissions scenarios. By the year 2100, sea level is projected to rise approximately 22 inches. The cost of protecting and maintaining the coastline and sand replenishment is expected to cost $1 million-$3 billion through the end of the century.
With risks to human health expected as a result of climate change, it is also expected that availability of health insurance will be reduced, and the cost of insurance will increased. With rising sea levels and expected increases in severity and frequency of storm events on the Atlantic coast, insurance on property may also become difficult to obtain, and will likely become more expensive. Some major insurers have already withdrawn from the coastal areas in recent years.
As sea levels rise, there is an increased risk for saltwater intrusion into freshwater drinking supplies, which is difficult to stop and costly to repair. The risk of saltwater intrusion is exacerbated by predictions of increasingly frequent and severe storms. Increased sea levels also pose a serious risk to transportation agencies, with the potential for damage to roadways, bridges, railways and other utility systems from more frequent and severe storm events, as well as flooding and structural failure in high heat conditions.
The Long Island lobster population has long been in decline, with nearly 70% of the population lost due largely to warmer waters. It is projected that in both high and low-emission scenarios that the lobster fishery will collapse completely, as water temperatures will have surpassed the critical threshold for heat stress.