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Given that warmer temperatures and seasonal changes in precipitation are expected across the region, it is reasonable to expect that soil moisture regimes will also shift. Longer growing seasons and warmer temperatures would generally be expected to result in greater evapotranspiration losses and lower soil-water availability later in the growing season, thereby increasing moisture stress on forests. Further, increases in extreme rain events suggest that greater amounts of precipitation may occur during fewer precipitation events, resulting in longer periods between rainfall.

Some national and global studies suggest that conditions favorable for wildfire will increase, but few studies have specifically looked at wildfire risk in the Mid-Atlantic region. The duration of the fire season in the Mid-Atlantic region is closely linked with increases in average temperature during the summer (Liu et al. 2010). If drought or prolonged dry periods increase in this region as expected, fire risk will increase in both forests and local communities.

Warmer temperatures can lead to decreased soil moisture even without an associated decrease in precipitation, resulting in a temporary inability for a tree to meet water demand.

Numerous studies have tried to project the effects of climate change on forest productivity and carbon balance through modeling simulations and manipulative experiments. Studies of CO2 fertilization indicate that productivity may generally increase across the Upper Midwest. Warmer temperatures may speed nutrient cycling and increase photosynthetic rates for most tree species. Longer growing seasons could also result in greater growth and productivity of trees and other vegetation, but only if sufficient water and nutrients are available.

Impact models agree that many temperate species will experience increasing suitable habitat and biomass across northern Wisconsin and western Upper Michigan, and that longer growing seasons and warmer temperatures will lead to productivity increases for temperate forest types. The list of species projected to increase includes shagbark hickory, black cherry, bur oak, white oak, and a variety of minor southern species. Models also indicate that deciduous forest types have the potential for large productivity increases across the Upper Midwest.

Impact models agree that boreal or northern species will experience reduced suitable habitat and biomass across the Upper Midwest, and that they may be less able to take advantage of longer growing seasons and warmer temperatures than temperate forest communities. Across northern latitudes, it is generally expected that warmer temperatures will be more favorable to species that are located at the northern extent of their range and less favorable to those at the southern extent.

At a global scale, the scientific consensus is that fire risk will increase by 10 to 30 percent due to higher summer temperatures. For the early part of the 21st century, there is low agreement in this trend across climate models. By the end of the century, however, most models project an increase in wildfire probability, particularly for boreal forests, temperate coniferous forests, and temperate broadleaf forests. Studies from southern Canada also project more active wildfire regimes in the future.

Large variation exists for projected changes in precipitation for the Upper Midwest. Although individual model projections may differ, there is general agreement that annual precipitation is expected to increase slightly (2 to 4 inches) during the 21st century. Models also tend to agree that precipitation patterns between seasons may shift substantially. Averages across multiple climate models indicate that winter and spring may experience 20-30% more precipitation by the end of the century, while summer precipitation is projected to decrease by less than 10%.

Heavy precipitation events have been increasing in number and severity in the upper Midwest in general and for Minnesota in particular, and many models agree that this trend will continue over the next century. For example, storms in the 99th-percentile category incrased by 42% from 1958 to 2016 across the Midwest. Large storms are also expected to deliver more rainfall as well. In the Midwest, 20-year return storms are projected to deliver 11 to 20% more rainfall by the end of the century. Most heavy precipitation events occur during summer in the Upper Midwest.

Soil moisture is expected to change in response to warmer temperatures and seasonal changes in precipitation. Changes are likely to vary seasonally as well as geographically. More intense and prolonged precipitation events would be expected to create wetter soil conditions, while increased temperatures and less frequent rainfall events would lead to drier soils .