Bulletin of the Atomic Scientist, April 20th 2026

Posted: 20th April 2026

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April 20, 2026

Looking out towards the La Plata and San Juan mountains in Colorado’s Mesa Verde National Park in January. (Allie Mazurek/Colorado Climate Center, Colorado State University/High Country News)

What the historically low snowpack in the American West means for water and wildfire this summer

“Mountain snowpack is the West’s largest reservoir, providing water for 100 million people and diverse ecosystems,” writes Anna Marija Helt. “The amount of water stored in the snowpack historically peaks around April 1. But this year, the snowpack in many places was absent, or nearly so, by then—the lowest level in the 45 years since automated measurements began.” Read more.

Taking a sledgehammer to the nuclear nonproliferation regime

“President’s Trump’s disdain for the rules is endangering world order in many ways,” write Frank N. von Hippel and Seyed Hossein Mousavian. “We cannot leave defense of the nonproliferation regime for later, however. If we do, we may find ourselves in a nuclear-armed crowd.” Read more.

UPCOMING VIRTUAL EVENT

Expertise on Demand: AI in Journalism, Academia, and Thought Leadership

Evidence of AI usage is increasingly occurring in peer-reviewed academic works, and databases are starting to show evidence of AI hallucinations. At what point does algorithmic assistance become an intellectual liability? How can the public distinguish between expertise built on a career of education and experience, against an armchair expert using AI tools?

This Wednesday, April 22, join us as we explore these questions and more. Register here.

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How to counter health misinformation when it’s coming from the top

“Overall, health misinformation is most harmful when it is being spread by individuals with power and through well-resourced campaigns,” writes Lisa Fazio. “In other words, exactly what is happening within the Trump administration now.” This Bulletin magazine article is available to all readers for a limited time.

The AI Power Trip

Almost three years after its launch into the public sphere, generative artificial intelligence has permeated nearly every crevice of human life.

“The AI Power Trip” is a year-long Bulletin project examining how those developing AI applications are gaining control of the world’s governance, information ecosystems, energy resources, military-industrial complex, and more. This project is supported by the Future of Life Institute. If you haven’t yet, explore the series here.

Recent articles

• ‘It’s just madness’: Trump administration to close three-quarters of Forest Service research stations
• It seems Washington needs to be reminded of the Nuclear Non-Proliferation Treaty
• Python Cave tours? The ways disease jumps from animals to humans are evolving
• What this Norwegian ‘close call’ says about a world without New START
• When the war in Iran comes home: Why the US isn’t ready for increasing hybrid threats

QUOTE OF THE DAY

[Why can’t the US get comfortable with nuclear waste storage, like Finland or Sweden?] “It’s because we have a much longer and more complicated history with nuclear. How to reckon with that history is actually what a lot of communities are asking, rather than just going forward.”

— Jennifer Richter, associate professor at Arizona State University’s School for the Future of Innovation in Society, “Wyoming communities want time to consider embracing nuclear energy, as feds rush to expand industry,” The Washington Post

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