The Centers for Disease Control and Prevention (CDC) organized a three-day conference on climate and health. As the Trump administration took power, the conference was abruptly cancelled. So former Vice President Al Gore and his Climate Reality Project, former President Jimmy Carter, the American Public Health Association (APHA), public health expert Dr. Howard Frumkin, and others stepped in to fill the gap, putting on a one-day summit at the Carter Center in Atlanta last week.
Gore and leading scientists discussed key areas where climate change is expected to cause major human health impacts (due to time constraints, they left out discussing animal and plant health). In the first part, we covered the first four — infectious diseases, heat stress, air pollution, and allergens; here, below, are the rest:
Mental Health: Gore said except for Dr. Lise Van Susteren, with the Center for Health and the Global Environment, Harvard T.H. Chan School of Public Health, few seem to be studying the mental health impacts of climate change.
Dr. Van Susteren gave perhaps the most powerful speech of the conference, as so much of what she said hasn’t been in the spotlight before. She said the most negative weather impacts of climate change — flooding, storms — result not only in injuries and property loss, but a sense of displacement, which leaves an incredible “emotional toll.”
Shifts in temperatures also have a mental health impact. In higher temperatures, studies have found, there is a “40 percent increase in conflict, and 14 percent jump in conflict between groups.” There is increased unrest among all ethnic groups. She imagined a future with higher temperatures and more refugees resulting in increased conflict worldwide.
And in societies facing an influx of refugees, there has been a “sharp turn to the far right.” In a time of peril, “people regress and give up on their values.” In a state of anger and aggression, “systems can be easily overwhelmed. Faith in government can fail.”
More deeply, she wondered what happens to people’s unconscious psychological states when “the place they call home goes away,” when they can’t return to a place that has been irreversibly changed. She argued that the “fear, anger, sorrow, and trauma” of that experience can “push people to the breaking point” and result in “abuse, drugs, and violence.” She said more and more communities are experiencing this type of nostalgia for lost, damaged lands.
Furthermore, we will feel the loss of the natural world. With some scientists estimating that 30-50 percent of species could go extinct in the coming decades, “we will lose that the awe and wonder we get from biodiversity. The cost is our souls.”
Many people not currently directly impacted by climate change yet may still have “climate anxieties.” A group of climate Cassandras see “future disasters coming,” which takes a psychological toll. She point to children in Australia who are having a hard time focusing due to fears associated with drought and climate change. It has become so common it’s considered a new condition. In a startling statement, she then equated climate change with child abuse, and burning fossil fuels with aggression that puts people in harm’s way.
Food: Important food crops are heat sensitive. Each day corn is above 84 degrees Fahrenheit, there is a 0.7 percent loss in yield, Gore explained. With wheat, there is a 20 percent drop with a 1 degree increase. All those crops also need water, which is becoming increasingly scarce in many places. And another little known effect of rising carbon dioxide in the atmosphere is the reduction of nutrient levels in important grains. Zinc, copper, magnesium levels drop by 10 percent of more in common grains as CO2 levels rise, Gore said. This bodes ill for the world’s poor who rely on these grains for these nutrients and can’t afford supplements.
Dr. Samuel Myers, an expert on climate and food at Harvard University, took a step back to look at the big picture. He said “food demand is the highest in history, but climate change is affecting all food systems, threatening the quality, quantity of food and where it’s produced.” Some scientists have posited climate change could have a helpful fertilizing effect by raising temperatures and humidity, but the positive impact will be “smaller than thought,” and be likely far outweighed by the negative impacts.
With rising temperatures, the tropics can expect a 15-25 percent drop in yields. On top of that, more heat is “incompatible with long outdoor labor.” Fisheries peaked about a decade ago and their capacity is falling about 1 percent a year. Fisheries will also now move further towards the north and south poles. Water scarcity threatens livestock. With all these changes, Myers predicts the world will become increasingly dependent on food trade. This hits the poor the hardest, as they are “most susceptible to food price shocks.”
Crops will have less nutritional value. A group of scientists around the world have been growing 41 cultivars over 10 years in open-field conditions, but have been circling them in a ring of carbon dioxide at the levels of 550 parts per million (ppm), which is the level expected in 50 years. The scientists found that with all C3 crops, which include beans, rice, wheat, potatoes, there has been a drop in iron and zinc values along with protein levels. “These deficiencies are already a huge problem today in the world’s population. The effect of climate change may be that 200 million more people will have a new onset of zinc deficiency, and 1 billion people will have an existing deficiency exacerbated. There will be a similar effect with iron and protein, particularly in Africa and South Asia.”

Myers argued said just a decade ago, “scientists didn’t know that food would have less nutritional value. These complex unknown effects are worrying.”