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An ancient river dries up, unearthing a historic artifact submerged for centuries. Don't expect Indiana Jones to swing in with his whip to prevent it from falling into the hands of nefarious actors. This very real scenario is playing out around the world. In a Czech town near Germany's border, stone carvings dating back to the 1600s emerged as severe drought evaporated the Elbe River. In Serbia, the Danube's waters receded to reveal Nazi warships sunken in World War II.

"It's very strange, but it's a great time to be an archaeologist or a forensic anthropologist," says Dr. Lisa DeChano-Cook, professor in the Department of Geography, Environment and Tourism. It's also ominous and indicative of a more dire dilemma: Weather extremes are impacting humans at an increasingly continuous clip as climate change intensifies.

"The Colorado River used to flow all the way to the Pacific Ocean. It doesn't even hit Yuma, Arizona, anymore. And Lake Mead, with the Hoover Dam, is drying up," she says. "We're in a land of extremes at this point because of what we've done to our climate, and now we're seeing the effects of it."

While it's not uncommon to hear about natural disasters from time to time, it's the magnitude and frequency of extreme weather events that we should all be taking note of, DeChano-Cook says. Prescribed burns in April in drought-parched New Mexico grew out of control into the largest wildfire in state history. Record-breaking summer heat in the United Kingdom caused roads, runways and railways to buckle. But it's important to remember that climate change is much more than global warming.

"When we're talking about global warming, we're only talking about the temperature going up. When we're talking about global climate change, we're talking about the temperature going up and all the impacts that has, such as sea levels rising, melting of glaciers, acidification of the oceans and so on. Global warming is just a piece of global climate change. People use them interchangeably—and that's not correct."

The warming air also intensifies precipitation, because warmer air holds moisture better than cooler air. It's contributing to widespread, disastrous flooding all across the Northern Hemisphere. In perhaps the most extreme scenario to date, weeks of torrential rains paired with glacial melting left more than a third of Pakistan under water in August.

"For 40 days and 40 nights, a biblical flood poured down, smashing centuries of weather records, challenging everything we knew about disaster and how to manage it,'' Pakistan's Prime Minister Shehbaz Sharif told the United Nations General Assembly.

A similar story, on a smaller scale, is playing out in several areas across the United States. In September, Hurricane Ian roared ashore in Florida as one of the most powerful storms to hit the state in decades, devastating infrastructure and sparking a 500-year flood event. In July and August, areas of Kentucky, Missouri, Illinois and even Death Valley in eastern California—the hottest and driest place in North America—saw 1,000-year rain events.

"The storm systems that we're getting are producing these floods in different areas where a system wouldn't normally have done that," DeChano-Cook says.

In addition to the immediate threat to life, these extreme weather events come at an increasing cost. Cargo ships can't navigate rivers that have dried up, sending supply chains into chaos; floods and droughts are decimating agriculture; clean drinking-water sources are evaporating; and supercharged typhoons and hurricanes are turning neighborhoods into piles of wood splinters and concrete dust.

The National Oceanic Atmospheric Administration records what it refers to as billion-dollar weather and climate disasters. In 2021, 20 events—ranging from severe weather to wildfires to drought—caused more than $152 billion in damages. The increase in severity is apparent when comparing averages over decades: In the 1980s, the U.S. recorded about 3 billion-dollar events per year; the average jumped to 5.5 annually in the 1990s; there were nearly 7 events per year in the 2000s; and the number nearly doubled to about 14 billion-dollar disasters in the 2010s.

It's a pattern, says DeChano-Cook, that reflects a dire escalation in the Earth's climate cycles due to carbon emissions and other human activity.

"Without some strict guidance from governments across the world, it's not going to get better fast," she says, acknowledging the United Nations Paris Climate Agreement as a start. "We've gone through global warming; we've gone through global cooling. Now we're on this trajectory of warming where we're going up and up and up and up and up. And there's going to come a point of no return if something doesn't happen drastically fairly soon."