Immigration has been a touchstone of the U.S. political debate for decades, as policymakers have weighed economic, security, and humanitarian concerns. However, Congress has not agreed on comprehensive immigration reform for years, effectively moving some major policy decisions into the executive and judicial branches of government and fueling debate in the halls of state and municipal governments.
The twice impeached and now indicted former president, Donald Trump, placed the immigration issues at the center of public debate with his unprecedented efforts to curb immigration and reshape asylum policy. President Joe Biden pledged to reverse Trump’s actions and reform the system, but the ongoing COVID-19 pandemic and an ever-increasing influx of migrants have complicated his plans.
Over the past century, the Earth’s climate patterns have shifted, leading to more frequent and intense weather events such as hurricanes, heat waves, and droughts. The Intergovernmental Panel on Climate Change (IPCC) has predicted that if current trends continue, the global temperature will likely rise by 1.5°C above pre-industrial levels sometime between 2030 and 2052. While this may seem like a slight increase, it will have far-reaching consequences on ice sheets, ecosystems, and agriculture that will fundamentally change the Earth’s livability. Moreover, the effects will not be uniform, with high latitudes warming twice as fast as the rest of the world and arid regions expanding.
The climate can be viewed as the overarching framework within which all economic activities occur. The alterations in climate could have substantial implications for modern society, whether in low- or high-income contexts. However, humans possess the capacity to adapt and exercise free will. Thus, it is essential to be cautious not to adopt a form of environmental determinism that establishes a direct connection between projected climate shifts and subsequent migration. Instead, environmental factors are just one of several drivers that influence the decision of an individual or community to migrate. These drivers may interact with each other, and policy initiatives or personal circumstances could moderate their impacts.
An article by Alex de Sherbinin at Migration Policy Institute draws on growing evidence that increased migration results from environmental change. The evidence includes case studies, advanced statistical analyses, modeling, and the UK’s influential 2011 Foresight Report, Migration and Global Environmental Change.
Given the complexity of how climate factors impact migration, it is helpful to start with some general observations and definitions. Migration scholars have identified various “stylized facts” that explain how, why, and when people move. For example, push and pull factors in origin and destination areas drive migration flows, while barriers such as travel costs and border restrictions can limit movement. Migration tends to increase over time, and people are more likely to migrate to places with social connections. Selectivity also plays a role, as some demographic groups may be more prone to migration than others. Finally, economic motives often drive migration decisions. Environmental factors can and do influence all of these factors.