Global environmental change: A clear and present danger

Last July, shortly after president Trump announced the U.S. withdrawal from the Paris Climate accord, I wrote a piece for The News bemoaning the slow progress that has been made in addressing global climate change and controlling greenhouse gas emissions.

Since I wrote that column, Scott Pruitt, the current EPA administrator, has followed through on the president’s threat to roll back the Clean Power Plan reducing carbon emissions from coal fired power plants, announced plans to delay rules aimed at setting fuel efficiency standards for cars and trucks, attacked rules limiting methane emissions from oil and gas wells and attacked efforts to set appliance efficiency standards. This has occurred with little if any adverse political consequences for the protagonists and only a tepid response from environmentalists and public health advocates.

Yet survey after survey show that roughly 70 percent of the U.S. population believes global warming is happening. Of those, 50 percent attribute it mostly, or in part, to human activity. Here in Chittenden County the proportions are 76 and 60 percent respectively. (See Yale Climate Change Maps.)

What explains the lack of political urgency?
The answer is that, while most Americans perceive global warming as a threat, it’s a distant threat. Only 41 percent believe they will be personally harmed (38 percent in Vermont). Especially telling and important is that very few Americans (only six percent) are optimistic that humans can, and will, act to reduce the rate of global warming. While future generations may suffer, the perils are seen as far in the future. Of far greater significance is the fact that many Americans believe that reversing these trends is beyond their control.

If the goal is to mobilize and empower people, we have to abandon the default option of always talking about future risks. Threats to the Greenland and Antarctica ice sheets and to Pacific coral, as well as shifts in the migratory patterns of bird populations, are remote concerns for many. Instead of talking about temperature rises of 1 or 2 degrees C. (numbers no one understands), we need to focus on how changes already happening to the environment affect people’s health today.

A few examples

Fossil fuels
External costs associated with the extraction and transport of fossil fuels, such as land degradation and pollution of lakes and streams, are relatively easy to see and understand. But for those not living close to gas wells, coal mines or rail transport lines, the associated risks may seem remote. In addition to releasing carbon dioxide when burned, these fuels emit other gas products, such as sulphur dioxide and nitrogen oxides, agents closely associated with asthma, bronchitis and other pulmonary diseases. What’s not commonly known is that, along with these gaseous products, fine and ultrafine particles are also produced. Ultrafine particles can penetrate deep into the lungs and subsequently be distributed via the blood stream to the heart, kidneys and other organs.

In the last two months, two carefully conducted studies have been published, one in The New England Journal of Medicine and one in The Lancet, showing serious long-term health effects from these particulates. Other studies have also linked particle exposure to chronic systemic infection as measured by elevated C-reactive protein (CRP). Two things are worth noting: First, these studies were done on people over 65, so the effects on young adults and children are not known. Second, you don’t need to live near a power plant or smelter to be exposed—fine particles are also produced by car exhaust, lawn mowers and tractors.

Heat, drought and extreme weather events
The recent spate of cataclysmic weather events—California wildfires, 10 named hurricanes in the Atlantic this season, and drought spreading throughout the Midwest—are not all coincidence. While it’s impossible to pinpoint the direct cause of any one of these, it’s clear that the number and magnitude of such events is more than a statistical fluke. The warming of the oceans and the laws of thermodynamics suggest that these events will increase in frequency and magnitude over time.

But the indirect effects of global warming are also profound. Disease vectors such as mosquitoes, rodents, ticks and some species of birds are appearing in places, including Vermont, rarely seen before. The result? We are seeing higher rates of diseases such as Lyme disease, anaplasmosis, giardia and rabies than ever before. In addition, as we saw this past summer, we are seeing increased incidence of blue-green algae blooms (cyanobacteria) in our ponds and lakes.

In a fascinating article in Harvard Public Health (Fall 2017), Dr. John Spengler describes how changes in the outdoor environment (temperature, ozone concentrations, particulates) can cause changes in our home environments. Higher temperatures increase “off-gassing” from volatile organic compounds that leach out of common materials found in the home. For those of us living in places such as Vermont where extremes of cold (and heat) may cause us to spend additional time indoors, these risks are not trivial.

Crops and soils
Finally, the impacts of climate change on crops and soils are clearly of special interest to Vermonters. Average annual precipitation has increased by almost seven inches in the last 50 years, with the frequency of heavy rains (greater than one inch) having also increased. This means more runoff, more pesticides and heavy metals in our streams, and more fertilizers and animal waste products finding their way into our aquifers. But what crop scientists are only just beginning to understand is that as global CO2 levels rise (an increase of 40 percent is predicted by 2100) there is a shift in the micronutrient chemistry of staple crops like maize and soybeans that in turn may lead to serious adverse health consequences for both humans and animals that rely on them.

The Vermont Department of Health is one of 10 states to receive funding from the U.S. Centers for Disease Control and Prevention to alert residents of the state to the impact and implications of many of these environmental changes. This program, called Building Resilience Against Climate Effects (BRACE), provides a great source of information for Vermonters seeking additional information on the local effects of global environmental change.

Where does this leave us?
We need to reorient our thinking about global climate change and focus on how it impacts our lives today. These threats are real, immediate and, at least partially, solvable. To paraphrase Gina McCarthy, former EPA administrator: The harm inflicted by climate change happens daily regardless of where you live, your lifestyle, race, education or how fat your wallet is. Hopefully, if we focus the discussion on effects occurring today, apathy will give way to action.

Jim Hyde is associate professor emeritus at the Tufts University School of Medicine. He lives in Charlotte.