Scientists warn of climate change food impact

Dianne Anderson
By Dianne Anderson
For business
Overfishing is one culprit, but climate change also is a problem.

It seems like such a simple dinner order: Grilled salmon, side of rice and corn, with the wheat artisan sourdough – hold the micronutrients. But scientists warn that menues will likely get shorter in the coming decades. The villain: Climate change.

Great fisheries are shrinking from de-oxygenation and warming waters. One-fourth of the land surface has been degraded to a point of non-productivity. As the bees die out, food supplies will also tighten, resulting in projected annual global crops pollinator loss at $577 billion. That’s with a “B.”

What sounds like just another dystopian cult classic comes, in reality, from recent warnings by the United Nations of how human-caused climate change is destroying the planet. Given the current trajectory, there will not be enough food to support 10 billion people in the next 30 years, even as available food staples become less nutritious.

Douglas Rader, and Ph.D. and chief oceans scientist at the Environmental Defense Fund, explains that precarious patterns already are in play.

In the world today, he says, more than a billion people experience direct health impacts from loss of access to health-determining micronutrients associated solely with failing fisheries management.

What’s at stake? Protein and micronutrients

Overly intensive fishing is partly to blame. But climate warming is a major threat to the world’s oceans. Rader asserts that without effective management, the fish population’s ability to reproduce will continue to collapse. “By about 2030, between 80-90 percent of all the important fish that people eat around the world will be severely depleted if fisheries management doesn’t turn around,” he says.

If fisheries management reform happens, the best case scenario, he explains, is that total fish populations could be increased by about 30 percent and the ocean’s ability to feed people can increase significantly from where it is today.

However, those estimates – from the first paper on fishery reform that he co-authored in the proceedings of the National Academy of Scientists – don’t actively factor in climate impact. In more recent findings, he and co-authors looks at what happens with climate change and whether the food supply actually can improve under current warming conditions.

The answer: It all depends on how hot it gets.

NASA reports that 2016 was the warmest year since 1880, and that the ten warmest years in the 139-year record all have occurred since 2005, with the five warmest years being the five most recent years.

If it begins now, Rader says, proper fishery management with no more than 1.5-2 degrees increase in warming can help the ocean keep feeding people for the short term. If the warming increases and if emissions are not kept low, he notes the ocean’s ability to sustain life support systems declines fairly quickly.

Projections by the UN are that world fisheries will be in serious trouble by 2030.

More CO2 means more ocean acidification

As carbon dioxide increases and the earth warms, fish experience changes in their ability to survive the acidifying ocean, and they are migrating from the tropics toward the poles, especially in the northern hemisphere.

“You have sea level rise going on and bigger storms, you have this joker in the deck of acidification. We don’t know how the acidification part of this equation will affect the underlying ecology of the system,” Rader says.

But, he cautions, with overfishing and climate warming, the big fish already are disappearing, pointing to the East China Sea, Japan, and Korea.

“Nothing there is more than a year old,”  he adds. “In the short term, they may be able to keep harvesting – like a cornfield in Iowa.”

Scientists also question effective fisheries management, called “fixing fishing” as the best short term solution to overfishing and deal with long term climate impacts. If implemented, he explains, about half of the ocean’s protected endangered species, threatened species, could be restored.

Aquaculture, or fish farms, may be an option. However, in its current form, that’s too simplistic. Given the worst case scenario, the world has to effectively manage fisheries and improve fish farming methods. “There is no free lunch,” he says. “Fish farming requires feeds and chow to come from both plants and wild-caught fish to grow fast enough to get to market to feed the people.”

Scientists worldwide have sounded the alarm for many years about coral reefs dying, the loss of sea grasses, and other vulnerable coastal habitats. As the water warms and sea levels rise, the storms intensify.

Grains and rice face an uncertain future

Nathan Mueller, assistant professor of Earth system science at the University of California, Irvine, co-authored a beer study showing how drought-impacted areas have put barley at risk, but that’s just one of several major hits to grain supplies. There is a significant, or continuing, depletion of nutrients to other world food staples, including wheat, rice, and maize.

He warns that climate change can influence both the quantity and quality of the grains produced. Often, there are concerns about the quantity; however, he notes that decreased grain yields are expected in certain regions with warmer temperatures and more extreme events.

“Less commonly appreciated is the fact that rising carbon dioxide, one of the key greenhouse gases that drive changes in the climate, also appears to directly have an influence on the magnitude of protein and important minerals in grains. These declines could exacerbate malnutrition in some regions – for example through zinc deficiency,” he adds.

Global emissions of carbon dioxide had appeared to plateau for several years, but since his beer study, he said CO2 has also ticked up in the past year. The bottom line: More efforts at mitigation will be needed.

In light of stubbornly persistent use and support for fossil fuels in the U.S. and worldwide, he believes climate impact can be mitigated with support for farmers as they try to adapt to changing conditions. “New cultivars, changes in planting dates, adopting irrigation, and so on that could help ease the impact of climate change,” he adds, however, with another important caveat.

“Extreme events are going to be more difficult to adapt to than just average changes in climate,” he says.

Dianne Anderson covers education, health, and city government stories with an eye on legislative impacts to diverse communities. She has received awards from the American Cancer Society – Inland Empire, and the Southern Poverty Law Center. Over the years, she has reported for the Long Beach Leader and the Inland Valley Daily Bulletin and been a contributor to the Pasadena Weekly.

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