Down in the mud: Arizona researchers probe seabed for clues about monsoons

TUCSON – Thunder and lightning. Dust and wind. Flash floods. These hallmarks of the North American monsoon are well-known to Arizonans, and new research indicates these impressive storms have been a part of the Southwest’s climate for millions of years.

Jessica Tierney, a geologist and associate professor at the University of Arizona, leads a research team that’s analyzing mud samples taken from the seafloor in the Gulf of California.

“What we are interested in knowing about is how the monsoon is going to change in the future, and how we can prepare,” Tierney said. “But in order to do that, we have to actually go back and look in the past.”

It’s impossible to predict when and where monsoon storms will strike. But Tierney and her team’s work could help climatologists better understand the power of the North American monsoon, which hits the Southwest from June through September, and what its intensity may be like in the future.

Deep-sea mud contains chemical signatures that hold secrets about the earth’s past. One area the team is looking at are the waxes that plants secrete to hold in moisture and control evaporation.

“The waxes that are growing on plants that receive more monsoon rain have a special chemical signature versus plants that were growing in times that had more winter rain,” Tierney said.

“By measuring the chemistry of these plant waxes, we can actually go back in the past and tell you how much summer versus winter rain there was.”

Tierney is more interested in summer rain because that’s when Arizona’s monsoon occurs. If her team can get a better idea of how much rain fell during the summer months of the latest ice age, they can conclude how intense the monsoon was back then.

The team has already found that the North American monsoon was suppressed but not completely gone during the latest ice age, which ended more than 11,000 years ago. Tierney said its research also suggests the monsoon has been a persistent feature of the Southwest’s climate.

The research has stirred up the interest of other scientists.

Deep-sea mud contains chemical signatures that hold secrets about the earth’s past. Researchers are studying mud to understand the intensity of the monsoon millions of years ago. (Jordan Evans/Cronkite News)

“If they can go down to deeper layers where it was a warmer period and interglacial, something where we had similar kind of CO₂ that we have now, and they can see how was the monsoon consistent then, was it more intense or was it less intense, that will be very useful information,” said Nancy Selover, Arizona state climatologist.

“Right now, global climate models don’t do a good job predicting precipitation from the monsoon,” she said, noting that the monsoon might be 10 percent wetter or 10 percent drier. “If we can get a good idea of whether the monsoon will be more or less intense, we will really have a good idea of which it will be.”

Tierney, who will be one of the authors of the Intergovernmental Panel on Climate Change report expected in 2021, hopes the study can be useful for policymakers.

“Our work that is done here could be very useful for water resource management. If we have a better idea on the how the monsoon could behave, it could certainly help people in the Southwest plan for future drought.”

The team is looking to collect mud compounds from even deeper layers in the floor of the Gulf of California, also known as the Sea of Cortez. Tierney said that could help them answer how the monsoon acted millions of years ago, when the planet was as warm as it is today.

Monsoons aren’t just felt here in Arizona, but in South America, Africa and Asia. They are classified as a seasonal change in the winds in the upper atmosphere. The North American monsoon can be described as a formation of upper-level clockwise circulation, also known as high pressure, over the mountains of Mexico, New Mexico and west Texas.

This formation creates atmospheric rivers from the Gulf of Mexico and the Gulf of California, which bring in high levels of moisture to the deserts. The mountains across the area lift the intensive heat at the surface into the atmosphere, giving way to enormous thunderstorms.

Is the changing climate making you anxious? You’re not alone.

COLORADO SPRINGS, Colo. – We love our rivers, our mountains, our forests, deserts and wildlife in the West. They’re part of our economies, our lifestyles and our identity. But that very connection makes us vulnerable to a growing mental health problem: climate anxiety.

Wander around any town center or school campus around Colorado Springs and ask people their feelings about climate change and you might hear the words “scared,” “worried,” “dread” or “grief.”

Things just got even scarier with the United Nations’ latest report on climate change. It said the world had already reached a 1 degree Celsius increase above pre-industrial averages and that, “Limiting global warming to 1.5ºC would require rapid, far-reaching and unprecedented changes in all aspects of society.”

This news alone is enough to make anyone anxious. And such groups as the American Psychological Association and the American Psychiatric Association are paying attention. They’re publishing reports on how the fear of climate change can harm mental health.

Sabrina Helm, a researcher at the University of Arizona, wanted to find out who among us is the most vulnerable. She did a survey of several hundred people and found that “people who have a concern about nature and the environment in general, plants and animals, those are the ones who also report highest ecological stress. Unfortunately, also depression,” she said.

Helm believes people in the deserts of the West are especially sensitive because they “are very aware about how fragile the natural environment is. It doesn’t rain one year, and the changes are tremendous,” she said.

For Helm, who moved from Germany to the desert West some years ago, all of this hits home.

“It seems very dire to me,” she said. “If you read so much of the research, which paints not such a nice picture of future developments. … It affects researchers as well.”

In fact, based on Helm’s research, people who study the environment may actually be among the most affected by climate anxiety.

That includes Michael Lucid, a conservation biologist in northern Idaho. A few years ago, Lucid and his wife discovered a new species of slug, only to find it’s vulnerable to climate change.

Michael Lucid, a conservation biologist in northern Idaho, says climate change is part of his everyday reality as a scientist. (Photo courtesy of Michael Lucid)

He said it was disorienting to add a creature to the known world and simultaneously fear for its future. But climate change is part of his everyday reality as a biologist, as a parent and as a mountain dweller, he said.

“The last two summers in August have just been horrific smoke,” said Lucid, “and that has really gotten people talking about climate change.”

He said it makes him sad, but it also motivates him to work harder to find solutions for wildlife to survive and adapt.

This positive attitude fits with Helm’s research, which found that people who are the most stressed or depressed about global warming also tend to be the most proactive about finding solutions.

Laura Schmidt is a perfect example of this. She’s a recent environmental humanities graduate from the University of Utah.

Schmidt said the more she learned about the environment in graduate school, the more her anxiety increased. “And then I realized, you have to do something,” she said.

So she started convening support groups in Salt Lake City for people to talk about their climate anxieties. The groups became what she now calls the Good Grief Network. She said climate anxiety is something mainstream psychotherapy just hasn’t addressed head-on yet.

“Seeing the world around us come crashing down or be changed in ways we can’t even imagine,” Schmidt said, “is definitely going to have a psychological toll on us.”

So she’s growing the Good Grief network beyond Utah, and even into Canada and Europe. While developing the program, Schmidt interviewed scientists, activists, and writers about how they cope during hard times.

“Almost everybody said that they had some sort of spiritual practice,” she said. For some people, it was taking a walk in the forest.

For some people, it could be their church. Tom Trinidad is the pastor at the Faith Presbyterian Church in Colorado Springs. He said he has a number of congregants who are deeply concerned about the environment.

Tom Trinidad, pastor at Faith Presbyterian Church in Colorado Springs, says many of his congregation are worried about climate change. (Photo by Ali Budner/91.5 KRCC)

“Some folks come to the church and they just want to be able to unburden their concerns and their hearts,” said Trinidad. “And that’s all we can do sometimes. But if you only say ‘Just trust God and there’s nothing you can do about it’ then that also robs them of the dignity of their human responsibility. And so we try to do a little bit of both.”

He noted Pope Francis’ lengthy treatise on actively dealing with climate change and said “all of us need to be talking about this.”

For Schmidt, it boils down to a simple choice.

“You can see this as a great opportunity for connection and for meaning and for community building,” she said. “Or you can sort of shut down and look the other way.”

This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Boise State Public Radio in Idaho, Yellowstone Public Radio in Montana, KUER in Salt Lake City and KRCC and KUNC in Colorado.