Sunday | November 19, 2017
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Carbon dioxide levels on the rise

Before beginning his talk Tuesday night, University of Hawaii at Hilo professor Jason Adolf noted that the crowd wasn’t the usual lineup of graduate students.

“And that’s a good thing,” the marine science department chair told the group gathered for the September meeting of Interfaith Communities in Action. About 25 people attended the meeting, which featured Adolf’s presentation on climate change and its potential effects on Hawaii.

“I think one of the important things to consider is the scope, the sheer magnitude of what’s happening,” Adolf said.

The Big Island has been instrumental in providing the data set documenting climate change. The oldest carbon dioxide monitoring station is at the Mauna Loa Observatory, where data has been collected since the late 1950s.

Adolf presented what is known as the Keeling curve, a graph of the observatory’s data. The curve shows not only the annual rise and fall in atmospheric carbon dioxide levels (these vary seasonally, and are akin to the planet “breathing,” Adolf said), but also the steady climb in baseline levels.

“If we were at equilibrium, this (graph) would be flat,” Adolf said. “It wouldn’t be rising. As the planet’s breathing, the total amount of carbon dioxide is going up.”

In 2013, the observatory recorded atmospheric carbon dioxide levels of 400 parts per million, a level that had not been seen in the Homo sapiens era. On Tuesday, the daily level measured at Mauna Loa was 396.99 ppm.

Historic levels of carbon dioxide going back 800,000 years have also been calculated, using samples from air bubbles trapped in Antarctice ice cores. Placed on a graph, these levels fluctuate up and down over the millennia, never passing 300 ppm, before they begin a steep, nearly vertical rise.

The jump visualized on the graph “really puts in perspective more than anything for me,” Adolf said.

“There really is no question it’s increasing primarily because of humans burning fossil fuels,” he said. The Intergovernmental Panel on Climate Change, a body of 195 member nations created in 1988, released a report in 2013 in which climate scientists expressed 95 percent certainty the current global warming was a human-caused phenomenon.

Typically, climate scientists speak in terms of predictions for the next 50 or 100 years. But many predicted changes have already come to pass, including rises in average sea level.

“This is a huge factor for island communities,” Adolf said.

Average surface temperatures in the ocean have risen, which in turn affects air temperatures and the strength of the trade winds. Rising ocean temperatures and increased levels of carbon dioxide create acidification, which affects “anything that makes a shell out of calcium carbonate,” Adolf said. It also leads to coral bleaching.

And changing temperatures can lead to certain diseases, such as dengue fever, being spread more easily as conditions become more favorable for their insect vectors.

Still, the solution isn’t easy or straightforward, given how dependent the world is on fossil fuels.

“It would really be a bad thing if we didn’t have oil all of a sudden,” Adolf said. “Although we know we have to get away from fossil fuels and toward renewables…we’re not prepared to do it at this point.”

That’s particularly true for Hawaii, he said, where “we depend absolutely on oil-based transport of goods.”

Pre-European contact, Hawaiians were wholly self-sustaining, using farming and fishing practices that supported a population of about 623,000, according to a recent UH-Manoa study.

“Hawaiian sustainability relied very heavily on the ocean,” Adolf said. But the ocean “has been impacted for so long that most people don’t know what it’s supposed to look like anymore.”

Small changes, like recycling more (“It’s such an easy thing to do,” Adolf said) combined with institutional ones, like colleges divesting from their fossil fuel holdings, add up over time. But ultimately, change must come on a much larger scale.

One of the attendees was Mina Alessio, 10, who raised questions about the climate change’s impact on extinctions and animal migration patterns.

Alessio’s questions were inspiring to Adolf.

“It’s a generational thing,” he said. “They institute the changes.”

Email Ivy Ashe at iashe@hawaii tribune-herald.com.

 

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