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Evidence indicates that an increase in temperature and greater moisture stress will lead to increases in these kinds of stressors, but research to date has examined only a few species. Invasive species are already a persistent and growing challenge across much of the United States. Changes may exacerbate this problem, as warmer temperatures may allow some invasive plant species, insect pests, and pathogens to expand their ranges farther north. Northern Minnesota may lose some of the protection offered by a traditionally cold climate and short growing season.

Evidence at both global and local scales indicates that growing seasons have been getting longer, and this trend is projected to become even more pronounced over the next century. As seasons shift so that spring arrives earlier and fall extends later into the year, phenology may shift for plant species that rely on temperature as a cue for the timing of leaf-out, reproductive maturation, and other developmental processes. Longer growing seasons could also result in greater growth and productivity of trees and other vegetation, but only if balanced by available water and nutrients.

In the Upper Midwest, the duration of frozen ground conditions suitable for winter harvest operations has already shortened by 2 to 3 weeks in the past 70 years. Cold-season soil temperatures are projected to increase between 1.8 and 5.4 °F by the end of the century, and total frost depth is projected to deline by 40 percent across northern Minnesota by the end of the century. These conditions could increase water infiltration into the soil and reduce runoff, but they may also lead to greater soil water losses through increased evapotranspiration.

A variety of models project that across the Upper Midwest, more winter precipitation will be delivered as rain, more snow will melt between snowfall events, and the snowpack will not be as deep or consistent. Lake-effect snowfall may increase in the short-term, but these events may convert to rain as temperatures increase.

Northern Minnesota has already warmed more than 1.5 degrees since the first half of the 20th century, which is one of the fastest rates of warming across the country. All global climate models project that temperatures will increase with continued increases in atmospheric greenhouse gas concentrations. More warming is projected under a high climate scenario (RCP 8.5) and more moderate warming is projected under a moderate climate scenario (RCP 4.5).