On a regular basis, Minnesota has insect plagues. The most famous is the locusts that would look like an incoming snowstorm. This year we may have the tent caterpillar invasion. Our cold spring may have saved us this year, although there is just enough seed population that the tent caterpillar invasion will happen one of these years. Just to give you an idea of the cycles, here is a chart published by the Minnesota DNR.
Tent caterpillars flourish until they eat everything. If they eat everything before they mature then there are no seed sacs for future years. Otherwise they form seed sacs that survive very cold winters. The good news is that in any case, they die off half way through the summer. However, trees that are already stressed also die off. A defoliated forest is very ugly.
With climate change, I am expecting that trees are more stressed. There are more droughts, more heavy rains, and generally more bad weather. So when this tent caterpillar invasion happens, I think it will have a more significant impact.