Some of the global forms of climate change develop rapidly and can be difficult to detect. New, diverse situations may develop imperceptibly and unexpectedly. The effects of climate change can be unpredictable, escalate rapidly or occur over a long period, due to the complex mechanisms involved. The impacts on societal functions can be direct or indirect, or they may have ripple effects. It is often difficult to control spill-over effects and anticipate exposure to risks, because they are caused by complex chains of events.

As droughts increase, forest fires and wildfires become more frequent, grain yields decrease, and food shortages grow. Large areas may turn into uninhabitable deserts. The ice cover provided by continental glaciers and the Arctic Ocean is melting. In addition, thermal expansion is occurring in seawater. Together, these factors will cause sea levels to rise by up to one metre by the end of this century. This is a growing threat for coastal settlements, especially lowland settlements on all continents (Bangladesh in Asia is a compelling example). The very existence of some of the small island states located in the Pacific Ocean is in danger.

The worst consequences of climate change are occurring in countries with rapid population growth – for example, in Africa. Climate refugees are people who are forced to leave their homes because of the effects of climate change. The driving factors can be natural catastrophes, such as floods or storms, or a slow, but steady deterioration in living conditions. While most climate refugees move within their home countries, some go further. According to the World Bank, 140 million people have already been displaced by the consequences of climate change in Africa, Asia, and Latin America. This number is projected to grow strongly over the next 30 years.

According to the UN Human Rights Committee, climate refugees cannot be obliged to return to their home countries, and the United Nations High Commissioner for Refugees (UNHCR) affirms that they have the right to international protection. The migration of millions of people poses considerable challenges for border management, migration management and the maintenance of public order in the destination areas.

The effects of climate change exacerbate existing crises. For example, one of the root causes of the so-called Arab Spring (2011), as well as many conflicts in Africa, is the prolonged drought in the region, partly caused by global warming. Likewise, the Syrian civil war was exacerbated by an exceptional drought in the region. It complicated farming, causing people to move to cities, raising food prices, stoking tensions and leading to a large-scale exodus to Europe. Environmental changes in the Sahel region of Africa have raised tensions between farmers and nomads. When drought deprives farmers of their livelihoods, the temptation to join criminal organisations and terrorist groups becomes even more attractive.

Forest fires, storms and heavy rainfall require constant readiness on the part of territorial and maritime rescue services. In California and Australia, for example, large-scale wildfires are an annual phenomenon – made only more intense by relentless climate change.

The northernmost parts of the globe are warming faster than the rest of the globe – up to four times faster. The Arctic is rich in natural gas, crude oil, minerals and fish reserves that have not been exploited so far, due to both the harsh climatic conditions and the economic unviability. However, the reduction of sea ice and glaciers, as well as the melting of permafrost, will make it possible to both open arctic sea routes and utilise the available natural resources. On the other hand, the control of the maritime areas and continental shelves of the Arctic Ocean, and the natural resources therein, remains partly unresolved, and is therefore a potential source of serious disputes.

Read more in the menu The Security Political Significance of the Security of the Arctic region (link).

The increase in extreme weather phenomena will also have security-related consequences in developed countries such as Finland. Droughts, severe storms, heavy rainfall and floods are increasing, and are threatening the critical infrastructure of societies. Global warming is also affecting primary production and the exploitation of natural resources, as well as the viability of residential areas whose economic structure is sensitive to the effects of climate change, such as coastal areas and archipelagos.

In Finland, the civil service has been assessing the risk factors caused by climate change for many years. “The National Risk Assessment 2023” published by the Ministry of the Interior identifies the main risk factors that apply to society. According to the Assessment, Finland must prepare not only for the effects of extreme weather phenomena, but also for those risks that originate outside the country’s borders – that increase the likelihood of large-scale immigration, and that will affect industrial operations and the security of supply, for example.