Volcano Pacaya as seen from Antigua, Guatemala.

The president and his supporters say they want to solve illegal immigration by building an immense wall along our southern border, turning local police into immigration agents, and applying “severe vetting” to immigrants from certain countries—all of which are predominantly Muslim.

Opponents say these proposals suffer from over-simplification and racism. But there’s an even bigger problem: These “fixes” fail to understand that we can’t address immigration if we continue to deny the science of climate change, because increasingly, climate change is driving global human migration.

Let’s first acknowledge that our border with Mexico is a place of hardship, violence and injustice. Let’s also recognize the wrenching reality that many of those pressed against our border are children.

In fiscal year 2016, nearly 60,000 unaccompanied children were apprehended at our southern border. Even as the president and his supporters lump them together with “murderers and rapists,” the U.S. Border Patrol reports that they’re kids 17 and under, who, by a 4-to-1 margin, are from Guatemala, Honduras and El Salvador—not Mexico. Nearly 75,000 of the other people apprehended in 2016 were members of migrating families, mostly from the same three countries. Overall, Central Americans outnumbered Mexicans apprehended at the border in both 2014 and 2016. This reflects a trend showing fewer Mexicans and single adults illegally entering the Unaited States.

Migration from Central America is a reaction to pervasive violence and extreme poverty. Guatemala, Honduras and El Salvador have some of the world’s highest murder rates, fueled by gangs and drug cartels. For children and families, conditions are terrifying. This drives desperate migration, both internally and externally to Belize, Costa Rica, Nicaragua, Mexico and the United States. It is a regional issue.

Increasingly, climate change worsens existing problems. The Centre for Research on the Epidemiology of Disasters shows that, in the last four decades, Central America has experienced a tenfold increase in extreme heat, drought, forest fires, storms and floods. Among the most affected countries are Guatemala, Honduras and El Salvador, where millions today lack reliable food due to drought-related crop failures. The resulting migration to urban areas stresses already over-burdened housing, education and other services. It worsens gang violence, drug trafficking and corruption, forcing people to flee.

The changing climate threatens yet more instability for Central America. The region’s volcanic soils are prone to massive landslides from increasing storms, and millions of people live beside rising seas. Often, local economies and infrastructure are ill-prepared for disaster.

Evidence also suggests that climate change helped ignite today’s war in Syria. Extreme drought beginning in 2006 withered crops and drove people to cities already swollen with Iraqi refugees and political discontent. The root causes of the war are complex, but we cannot ignore indications that climate played a role, thus contributing to the migration crisis now straining Europe.

For more than a decade, stretching back to the George W. Bush presidency, the U.S. military has warned that climate change will increasingly contribute to unrest and drive potentially massive human migrations that threaten our national security. Similar warnings have come from the International Organization for Migration, the World Bank, the Government Accountability Office (which reports to the U.S. Congress) and the Department of Homeland Security.

Their warnings, and the reality of a refugee crisis in both Syria and at our own southern border, underscore the value of the Paris climate agreement, which Republicans are presently working to undermine. Aside from its impact on reducing carbon emissions, it also provides for climate-change adaptation in Central America and other vulnerable regions. The agreement represents an investment in social stability that can help to relieve immigration.

The last Congress under President Obama saw the value in addressing the seed causes of migration, appropriating $750 million in 2016 for Central American support and aid. Such actions were part of a smart immigration strategy that also included modernizing border security technology, disrupting criminal smuggling outfits, and clear enforcement priorities that greatly increased deportation of convicted criminals.

In contrast, the Trump administration’s broad crackdown on illegal immigrants in this country reeks of xenophobia and prejudice. These emotional reflexes that fuel cries for border walls or bans on Muslim immigrants don’t reflect ethical or realistic thinking. Denial of climate science is a similarly emotional and unhinged response to a complex issue.

As climate and immigration change our physical and cultural landscapes in entwined ways, we must demand rational, science-based responses, not walls or other bad ideas driven by fear.

Tim Lydon is a contributor to Writers on the Range, the opinion service of High Country News, where this first appeared.