The defence and security forces of any country have plenty to contend with. Budgets are shrinking, price tags are climbing and threats are growing in complexity. At the same time, the world is heating up, meaning that the environment to which a force is deployed is going to be hotter and more extreme with each passing year. Climate change is already creating instability, elevating risks of violence and disaster that require armed forces to restore order. This trend will grow, adding to the burden of military budgets. Simultaneously, many militaries are under pressure to reduce their own environmental impact, which requires greater co-operation with civilian industry at all levels. Failure to address these issues in good time will have consequences for every society. In a defence context, it is not simply about reducing carbon emissions for the sake of meeting net-zero targets, or a matter of great-power competition. It is about preparing to deploy to more extreme environments, for example, extremely hot or dry, without risking human lives or compromising fighting ability. Of course, there are moral benefits, but militaries will always prioritise fighting capabilities above all else. Until recently, climate change was not understood to have played a role in shaping capability requirements. Science suggests that current patterns of global warming will result in rising sea levels, increased resource insecurity, more regular natural disasters and mass migration. In many cases, armed forces will be used to manage the response. In 2016, riots erupted in the Indian city of Bengaluru over water disputes with a neighbouring state. Businesses were ransacked, and people were killed and injured. A severe drought in 2019 led to protests in the Indian city of Chennai, and in 2022, both India and Pakistan suffered a long and hot summer with droughts and floods. These events are growing in frequency around the world, giving rise to the potential for conflict or instability – especially in those countries with very high rates of poverty. Though these issues are often seen as factors that might increase the potential for conflict, they are often communicated as either a national security risk or a defence risk, but not always both. It is increasingly clear that it is perhaps impossible to separate the two. Jordan is currently experiencing the effects of water insecurity, and recognises the increased potential for conflict, with Jordan’s former minister of water and irrigation, Hazim El Naser, recalling that a number of Arab uprisings of 2011 “came about in part because of water scarcity”. Drought-induced food insecurity can also contribute to political upheavals, creating stressors that increase the potential for war, as in Syria. Support to manage such insecurities has the potential to improve interstate relations generally, particularly in the Middle East and North Africa. With militaries continuing to contribute to international disaster relief, we are seeing a shift in the way nations and national armies view the threats that climate change presents. China has long recognised climate change as an urgent threat within its official security policy, in acknowledgement of the risk to its water, food security and energy. In June 2022, Nato released its “Climate Change and Security Impact Assessment” report, describing climate change as an “overarching challenge of our time” that will only “worsen as the world warms further”. Nato Secretary General Jens Stoltenberg describes the need to reduce emissions as vital to ensure that his organisation is able to remain ready to deploy at any chosen time while maintaining operational effectiveness. As such, it seems likely that governments will continue to demand more from their militaries to manage and protect resources and respond to domestic or international disasters, and so expenditure on climate-related solutions will increase regardless of political support for net-zero. In the defence space, climate change is not just about responding to the threats that the environment poses to security, it is also about armed forces limiting their impact upon the environment; particularly air forces, as planes typically emit the majority of military emissions. However, it is not all about carbon. For example, in the naval sector, many nations are experimenting with ways to reduce the impact of ships upon the environment, notably Britain, the US and Sweden. The adoption or incorporation of renewable or sustainable energy sources (such as solar panels, wind farms and alternative fuels) also allows for reduced emissions and expenditure on utilities bills, but has the added security benefit of improving military resilience by reducing its dependency on the national grid for power. It is in a state’s interests to “greenify”, with Ukraine, Kosovo and Iraq having shown that it is very easy for a force to target a national grid resulting in mass power outages, even with cyber-attacks. Excessive heat can also cause power outages, as California has recently had to consider. The war in Ukraine stands as a reminder that conflict can occur at any moment. Defence cannot afford to wait for the consequences of climate change to dictate its pace of development. Militaries cannot avoid their obligation to their personnel to provide them with the equipment and capabilities that they need to operate in a climate-changed world. Emissions associated with shelling and destruction are unavoidable, but it is no longer possible to ignore the need to engage with an increasingly volatile environment. Nations are waking up to the rising number of national security risks, and we cannot be sure of the nature or location of conflict or disaster, but we can be certain that a sustained military response will be required.
