Climate change won't just mean rising sea levels: It will mean more heatstroke, more diseases, more sewer overflows and less zinc.
Wait a minute — zinc?
Yes, zinc. It seems that when you grow staple crops like wheat, rice and soybeans in an atmosphere high in carbon dioxide, they have less of several key minerals like iron, zinc and calcium than the same plants grown today. That could lead to more people facing dietary deficiencies in a warmer future, even if they can grow the same amount of food, said Sam Myers, a Harvard researcher who has documented that effect in recent studies.
"If we'd sat down 10 years ago and tried to think of what the effects of anthropogenic CO2 emissions on health would be, one effect no one would have anticipated was it would make our food less nutritious," Myers said.
That was one of the potential consequences of a warmer world that was being discussed Thursday at a conference on climate change and health, revived after a post-election cancellation by the U.S. Centers for Disease Control and Prevention. Former Vice President Al Gore, whose Climate Reality Project cosponsored the event with the American Public Health Association, said the potential effects of climate change on public health need more attention.
Those consequences include not only greater odds of deadly heat waves or the potential spread of tropical diseases like the once-obscure zika virus, but greater stress on basics like public sewers as torrential downpours become more common, fueling the risk of waterborne disease, scientists and doctors said Thursday. But Gore and other speakers said efforts to cut the carbon emissions driving climate change can also pay health benefits, such as fewer heart and lung problems from people breathing smoggy, sooty air.
"Hope is justified," Gore said. "We are going to win this. We have solutions that are readily available."
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The conference was a shortened version of one previously planned by the Atlanta-based CDC. The health agency pulled the plug on the event after November's election of Donald Trump, who came to power calling climate change a "hoax" and vowing to bring back the sagging U.S. coal industry. But Georges Benjamin, executive director of the APHA, said state and local health authorities are still trying to head off that future even if the federal government pulls back.
"When we woke up on November 9, other than the fact the leadership had changed, most of the hardworking scientists and federal officials are the same people we've been working with for years," Benjamin said. "We'll certainly re-engage them, recognizing that there may be some additional barriers, because their new bosses may not have as sharp a focus. Some may not be opposed to it, it just may not be their focus. And we'll just have to continue to push them until we get their attention."
Dr. Ashsih Jha, director of the Harvard Global Health Institute, said that when the feds have dropped back in the past, "civil society organizations step in to fill that void. That's what's happening here."
"No one organization, even one as big as the federal government, gets to control the entire debate. Sending that signal was very important," Jha told reporters.
And for many in the public, highlighting the health hazards of climate change may be a better way to illustrate the problem than something as abstract as warmer summers or rising oceans — but there is a lot of data that still needs to be collected.
"Gathered today are probably most of the leading experts on climate and health," he said. "This is the most important issue facing the health of humanity over the next 50 years, and we're fitting them all into one room."
That room was at the Carter Center, the nonprofit democracy-promotion and public health effort launched by former President Jimmy Carter. The 92-year-old Carter got a standing ovation when he popped into the conference hall, saying climate-driven shortages of clean water in the developing world will make his organization's job harder.
"When those things happen, the poorest people are the ones who suffer from worms in their bodies and going blind," he said. "We want to be part of this process as much as possible."
Carter said that while the CDC "has to be a little cautious politically, the Carter Center doesn't." He added, tongue-in-cheek, "I have Secret Service protection."
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Even in the developed world, a warmer climate can mean higher risk for diseases. Small increases in sea surface temperatures can raise the odds of contracting illnesses from seafood like vibriosis and ciguatera, said Glenn Morris, director of the Emerging Pathogen Institute at the University of Florida. Warmer weather as fueled algae outbreaks not only in Florida, but as far north as Alaska, he said.
Another understudied issue several speakers noted was the effect climate change may have on mental health, particularly in the wake of extreme weather events and wildfires.
"When the place you call home is burned down, blown away, dried up or flooded; when you lose your possessions or your pets, your livelihood, your community; and see injuries, illness and death, the mix of fear, anger, sorrow and trauma can easily send a person to the breaking point," said Lise Van Susteren, a psychiatrist who has studied the subject. "Mental health professionals are seeing a range of psychiatric disorders – PTSD, major depression, generalized anxiety, a rise in the use of drugs and alcohol, domestic violence and child abuse."
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Editor's Note: This story was corrected to reflect that Georges Benjamin is the executive director of the APHA, not its president.