Lesson 2 - Impacts

During late medieval and early modern times, agriculture in the Nordic countries was very sensitive to the weather and the cycle of the seasons (see Lesson 3). The generally colder, less predictable seasons of the LIA were worse for most farmers. Nevertheless, the risks to agriculture depended a lot on local practices and conditions. Colder summers and shorter growing seasons reduced grain harvests all across the Nordic countries, but especially in more northern, inland, and upland regions. In these regions, crops were at more risk from early and late frosts as well as shorter summers and longer winters, which didn’t leave enough time to gather sufficient hay for animals. In warmer regions, particularly southern Sweden, summer drought could also be a risk.

First, when people and animals are together indoors during the winter, they are more likely to spread diseases. We see that effect even today when colds, influenza, COVID and other respiratory diseases infect more people during the winter “flu season.” During late medieval and early modern times, people could also infect each other through shared fleas and lice, which spread diseases such as typhus. This was often the case when poorer people had to live in cramped conditions or needed to huddle together for warmth, welfare or shelter. Second, the LIA affected food production (see above). When people are malnourished or face vitamin deficiencies, their immune systems are weaker. Cold and malnourished people during bad years of the LIA were therefore more likely to fall sick from common infections. Third, this was a period before refrigeration and other modern forms of food storage. People used techniques such as smoking, salting, pickling, and fermenting. Nevertheless, long winters without fresh produce meant more risk of sickness from moldy, rotting, or contaminated foods. Finally, during years of famine, people were more likely to move in search of help. These famine refugees faced terrible circumstances including poor clothing, lack of shelter, and lack of sanitation. The worst outbreaks of diseases such as typhus, typhoid, dysentery, and plague during early modern times were often spread by these famine conditions. The fact that some of these famines occurred during wars made the impacts even worse (see Lesson 4).

Probably not. Although cooling was an especial hardship for people in the North, what really made the LIA such a challenge was change and unpredictability. It took a long time before people in the Nordic countries developed the science, technologies, and institutions they needed to better understand climate and weather and to develop effective policies and responses (see Lesson 5). As late as the 1800s, the LIA could still deliver unexpected disasters.

Today, modern science, technologies, and institutions mean that we are better able to respond to challenges of climate change and even take advantage of some aspects of global warming. Warmer summers could help boost grain production and support new crops. Arctic shipping lanes will open, generating new economic opportunities.

Nevertheless, on balance, global warming will almost certainly do more harm than good, even in the North. Nordic countries will need to build and adapt expensive infrastructures for hotter summers, stronger precipitation and rising seas. We’ll face new hazards, including more invasive pests and weeds, heavier storms and hail, and more forest fires. Changing seasons will threaten our cultural heritage and seasonal traditions. Moreover, the Nordic countries will face the effects of disasters related to climate change around the world: overseas famines, conflicts, displaced populations, as well as economic and political turmoil will have impacts here, too. (See Lesson 6 for more on this topic.)