Our present ecocrisis drives human insecurity. Single weather events killed hundreds in 2024, even in wealthy countries such as the United States or Spain. And beyond that staggering toll in human lives lurk staggering amounts of money required to repair and rebuild. In the United States alone, inflation-adjusted disaster-attributable costs have reached on average $153 billion each year. These factors and others make global environmental change a severe risk to human security.

Yet these profound risks are manifold and unevenly distributed. For example, it makes a serious difference whether extreme weather hits a region that is prepared or unprepared—a fact that renders local vulnerability to environmental change “fundamentally a matter of political economy.”

To elaborate on this point, I recently conducted a study of two Pacific Island territories: The sovereign archipelago of Vanuatu and the unincorporated organized US territory of Guam (which some deem a US colony). While the ecocrisis brings significant risks to each of the islands, the impacts on residents are dependent upon their unique economic and political contexts. My comparison reveals two very different stories of human insecurity.

Vanuatu: A Vulnerable Archipelago and Climate Change

Climate impacts are ubiquitous in Vanuatu, and they are experienced by residents in ways both direct and indirect.

Climate change’s direct impacts on Vanuatu’s ecosystems and society are clear: sea-level rise, altered weather patterns, and an increase in the frequency and intensity of extreme weather events. Coral reef destruction results in reduced food security. Extreme weather damages the archipelago’s often fragile transport infrastructure which endangers the provision of basic necessities and the island’s economy—which relies substantially on international tourism.

The direct effects of environmental change contribute to human insecurity in Vanuatu. But beyond them, the nation’s political and economic contexts intensify the role climate impacts play in making its people insecure.

Vanuatu’s harmful colonial past initiated rapid (and often informal) urbanization and a self-reinforcing drive towards modern consumer lifestyles. This process contributed to its inhabitants’ climate vulnerability by challenging the design of urban climate adaptation, incentivizing less healthy diets and motivating locals to engage in controversial temporary work schemes in which Vanuatu residents migrate to Australia or New Zealand to provide labor for the food industry before returning to their homeland.

Understanding this context of a colonial past, contemporary economic struggles, and ongoing, rapid lifestyle changes gives a fuller sense of how climate change has become a danger to human security in Vanuatu

Guam: Overdevelopment and Militarization Create Environmental Vulnerabilities

More than 4,000 kilometers to the north, Guam is another island that faces climate change impacts—including rising temperatures, precipitation increases, and sea-level rise.

Yet unlike Vanuatu, Guam is a dependent, overseas territory of the United States—a part of that nation but with a lesser status than a full state in the union. This status limits the political rights of Guam’s inhabitants, can render them to be “forgotten Americans”. Yet being in the US, even as a dependent territory, also has brought economic (over-) development and introduced a more monetized economy than that of Vanuatu—or most, if not all, other Pacific islands.

Environmental change still poses a serious risk to human security on Guam, but this peril looks significantly different due to the context in which it takes place. Guam’s GDP per capita is more than ten times higher than that in Vanuatu. And while extreme weather events such as Typhoon Mawar in 2023 still hit the island severely, Guam’s economic development has reduced the accompanying climate-related dangers to its inhabitants. Severe heat waves are mitigated by the availability of air-conditioning, and it requires more severe downpours to undermine concrete-paved highways.

There are many other differences as well. Both island territories experience coral reef bleaching as a consequence of ocean warming, with subsequent impacts on human security. But while bleaching is primarily a food-related concern on Vanuatu (with a fishery that remains an important source of nutrition), its effects on Guam endanger a tourism industry that makes up a major share of the island’s economy.

While economic development enables Guam’s inhabitants to better cope with climate change, it has created new and complex pathways that translate environmental risks into human insecurity. Guam’s economy is founded upon the presence of the U.S. military and tourists, yet both tourism and militarization have damaged the island’s environment. Moreover, a study published in 2020 found Guam to bear “a disproportionate number of green criminal activity.” Invasive species such as the Coconut Rhinoceros Beetles and the Browntree Snake have also arrived in the wake of development, causing extensive damage to the islands ecosystems. The latter invasion is likely responsible for the extinction of birdlife on Guam, rendering the island’s forests eerily quiet and endangering their survival.

It’s All About Context: Climate Adaptation Must Be Comprehensive

While Guam and Vanuatu are two Pacific islands that face climate change, contextual factors alter both the substance and intensity of the impact. Vanuatu’s inhabitants experience a full range of climate-related human insecurity. Communities on Guam face different environmental challenges. Economic and political contexts play a key role in how our present ecocrisis unfolds on these two islands.

These significant differences also holds three insights that matter far beyond the specific case studies of Pacific islands. First, it is insufficient to protect human security by addressing climate change without considering other processes of global environmental change. A second insight is that how environmental change impacts human security is fundamentally linked to local political and economic contexts. And, finally, any adaptation to environmental change will fail if political and economic circumstances are not addressed within that process.