Speaker 1: Welcome to brain Stuff production of I Heart Radio. Hey
Speaker 1: brain Stuff, Lauren Vogel Bomb here with a classic episode
Speaker 1: from the podcast archives. Some of the effects of human
Speaker 1: induced climate change are pretty familiar and obvious, changing temperatures
Speaker 1: and weather patterns, But of course those effects have other effects,
Speaker 1: and this episode is about one of them. More storms
Speaker 1: means more sand is getting pulled from some beaches. Here's
Speaker 1: one of the things that researchers are trying to do
Speaker 1: about it. Hey brain Stuff, Lauren Vogel bomb Here. In summer,
Speaker 1: there's nothing like feeling the sun on your face and
Speaker 1: the sand between your toes. But the rising sea levels
Speaker 1: and stronger coastal storms associated with climate change pose a
Speaker 1: threat to the sands that make up our beaches. A
Speaker 1: common approach to combating erosion at US coastlines is beach nourishment,
Speaker 1: which is literally taking sand from one place off and
Speaker 1: off shore and pumping it on to a sand depleted beach.
Speaker 1: The question is can beach nourishment keep up with the
Speaker 1: ever increasing forces of climate change, or, like Sisyphus forever
Speaker 1: pushing his boulder up the hill, is adding sand to
Speaker 1: beaches an expensive temporary fix to a long term problem.
Speaker 1: We spoke with Bonnie Lutka, a post doc at Script's
Speaker 1: Institution of Oceanography at the University of California in San Diego.
Speaker 1: She said, I think there's reason to be concerned, but
Speaker 1: I also think there's still a lot we don't know
Speaker 1: about how long the sand stays where it goes, and
Speaker 1: how much sand you need to place on a beach
Speaker 1: to be effective or learning as we go. A study
Speaker 1: published by Luca in the June issue of the journal
Speaker 1: Coastal Engineering examines exactly what happened to sand deposited on
Speaker 1: four beaches in San Diego County in California. She and
Speaker 1: her colleagues used jet skis, a t v S, and
Speaker 1: other tools to continuously monitor sand levels and sand movement
Speaker 1: at the beaches over a period of about ten years.
Speaker 1: The research received funding from the U. S. Army Corps
Speaker 1: of an Engineers, the California Department of Parks and Recreation,
Speaker 1: the National Science Foundation, and the California Sea Grant. Among
Speaker 1: their findings, the team learned that the entire amount of
Speaker 1: sand added to San Diego's Tory Pines in two thousand
Speaker 1: one was washed away during a single storm. At another beach,
Speaker 1: the addition of a hundred and thirty eight Olympic swimming
Speaker 1: pools worth of sand contributed to the clogging and eventual
Speaker 1: closure of a nearby estuary. Among the team's more positive
Speaker 1: findings was that larger grained sand appeared to have better
Speaker 1: staying power than finer grained sand, and in some cases,
Speaker 1: the amount of sand deposited to a beach by natural
Speaker 1: forces was comparable to any mechanically added sand. Luca said,
Speaker 1: there is quite a bit of natural variability, so it's
Speaker 1: hard to pick out trends, but at our longest recorded site,
Speaker 1: we did see an overall pattern of erosion. The pattern
Speaker 1: of erosion that Luca's team observed at ground level is
Speaker 1: what's alarming to researchers assessing the long term future of
Speaker 1: US beaches. With climate change, sea level has risen about
Speaker 1: eight inches that's twenty since nine, according to the Intergovernmental
Speaker 1: Panel on Climate Change, and could rise three to five
Speaker 1: feet higher that's point nine to one point five meters
Speaker 1: by the end of this century. More frequent coastal storms,
Speaker 1: also associated with climate change, take a further toll on
Speaker 1: beaches by unleashing rough waves that eat away at the shore.
Speaker 1: We also spoke with Michael or Back, Professor emeritus of
Speaker 1: Marine Affairs and Policy at Duke University. He said, any
Speaker 1: beach nourishment is forever. It's like painting a house. Once
Speaker 1: you start it, you have to keep doing it forever
Speaker 1: to maintain. The problem is, with climate change and rising
Speaker 1: sea levels, there's going to be even more demand by
Speaker 1: orders of magnitude because the beaches are going to erode
Speaker 1: more and faster. Western Carolina University's Program for the Study
Speaker 1: of Developed Shorelines hosts an interactive database of beach nourishment
Speaker 1: projects across the US and their costs. As the data show,
Speaker 1: beach nourishment today is not cheap. Or Bach estimates the
Speaker 1: average cost of supplementing, saye that beaches comes out between
Speaker 1: one and two million dollars per mile of sand. As
Speaker 1: the demand for sand four beach nourishment increases, the cost
Speaker 1: will rise even higher. Orbach predicts, he said, in the end,
Speaker 1: there may not be enough sand that's economically recoverable to
Speaker 1: nourish every beach that people want to nourish. There's also
Speaker 1: an ecological cost. Studies have shown that dredging and depositing
Speaker 1: sand is disruptive to creatures living in the sand and
Speaker 1: the animals that eat them. While the research suggests those
Speaker 1: animals tend to recover after eighteen months to two years,
Speaker 1: beaches that undergo repeated nourishment to see significant declines in
Speaker 1: animal life. Despite the economic and ecological costs of beach nourishment,
Speaker 1: it may be among the few available options for preserving
Speaker 1: beaches in the future. Sean Vita, sec, and engineer specializing
Speaker 1: in ocean modeling at the University of Illinois and Chicago,
Speaker 1: points out that natural sources of beach sand, including rivers
Speaker 1: and eroding cliffs, have been suppressed by human built dams
Speaker 1: and protective coverings. Vita Sex served as lead off of
Speaker 1: a March seventeen modeling analysis from the U S Geological
Speaker 1: Survey that concluded that if no measures are taken, up
Speaker 1: to sixty seven percent of California's beaches could be completely
Speaker 1: eroded back to sea cliffs or coastal infrastructure by the
Speaker 1: year twenty one. The U S Geological Survey models showed
Speaker 1: that beach nourishment could protect some larger beaches that have
Speaker 1: undergone nourishment for decades, but that overall beach nourishment will
Speaker 1: have to be stepped up to a much faster pace
Speaker 1: to continue to be at all effective. Vita Sex said,
Speaker 1: if you just dump sand on a beach, that sand
Speaker 1: is not going to stay there forever. The current methodical
Speaker 1: rate of beach nourishment is insufficient against the coming sea
Speaker 1: level rise. Ludca said there is quite some debate about
Speaker 1: how climate change will influence the frequency and intensity of storms,
Speaker 1: and these storms will be more responsible for beach evolution
Speaker 1: than sea level rise. In the next few decades. It
Speaker 1: may become, she says, a matter of choosing between investing
Speaker 1: in ever pricier efforts to preserve beaches or standing back
Speaker 1: and allowing nature's forces to redraw the lines of where
Speaker 1: the ocean meets the land. Today's episode is based on
Speaker 1: the article can adding sand to beaches save them? On
Speaker 1: how stuff Works dot com written by Amanda Onion. Bran
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