Rising CO2 Levels Helping Create A Different World

The staggering amount of carbon dioxide dumped annually into the atmosphere continues unabated. In 2012 alone, emissions rose 1.4%, reaching a record high of 31.6 gigatons, according to a report released last week by the Paris-based International Energy Agency. It’s hard to fathom the magnitude of how much carbon dioxide that is -- just one gigaton is equal to one billion tons. One billion tons is about twice the weight of all seven billion people on earth—twice. 

This comes on the heels of news last month that we were inching ever closer to a potentially dangerous threshold: the Mauna Loa Observatory in Hawaii reported that for time since CO2 level measurement began in 1958, atmospheric concentration of the compound nearly topped 400 parts per million (ppm). "Today's rate of increase is more than 100 times faster than the increase that occurred when the last ice age ended," according to a National Oceanic & Atmospheric Administration (NOAA) press release about the readings. 

NOAA asserts this based on ice core data from the Antarctic that demonstrates over the past 800,000 years, CO2 has varied between 180 ppm in ice ages to about 280 ppm when the Earth went through warmer periods. Global CO2 averaged about 280 ppm before we began dumping carbon dioxide into the atmosphere when the Industrial Revolution began in the 18th century. In the absence of meaningful mitigation strategies, the EPA predicts that the U.S. is on track for temperature increases of four to 11 degrees Fahrenheit by century’s end and CO2 ppm counts up to 1000, shrouding cities under a suffocating carbon dome that would surpass Beijing on its worst air days.

So why is this happening, and why do scientists believe that burning fossil fuels and the rising level of carbon dioxide are the culprits behind a hotter planet, rather than just part of the Earth’s temperature cycle? The short answer is that carbon dioxide -- as well as methane and nitrous oxide -- is a greenhouse gas. These gases absorb extra solar radiation in the upper atmosphere and then release that excess heat into the lower atmosphere. This limits the planet’s natural cooling mechanisms and creates a hothouse environment under the canopy of carbon that amplifies temperatures on the Earth’s surface.  Many scientists are convinced this is due to the burning of fossil fuels, which began when coal came into widespread during the Industrial Revolution.

Much has been written about the overall impacts of climate change. Still, there is a big chunk of the story that’s under-reported, yet it may have the most immediate and profound impact on our lives:  how rising temperatures, higher C02 levels and the corresponding changes in ecosystems can have a serious effect on our health. The Lancet’s webpage dedicated to research on the topic says, “climate change could be the biggest global health threat of the 21st century.”

In the coming decades, a warmer climate could bring about higher levels of ozone pollution in the air we breathe, killer heat waves and outbreaks of deadly tropical diseases as vectors migrate to newly warmed locales. The likelihood of more extreme weather events --  droughts, floods, hurricanes, fires -- could spell disaster for people and agriculture alike. Because hot air holds more water, torrential rains, more ferocious hurricanes, and more dry spells because of heat-induced changes in rainfall patterns are all distinct possibilities. According to the Interagency Working Group on Climate Change and Health (IWGCCH), specific health challenges that could result include, increasing rates of asthma, allergies, severe respiratory infections, heart and lung disease, cancer, infectious diseases and even dementia and depression. The IWGCCH also says a harsher climate will increase the prospect of debilitating injuries and deaths, dislocation, the loss of social cohesion and lack of continuity in medical care in the aftermath of weather related calamities.

The spread of mosquito-borne dengue fever provides a foreshadowing of how infectious disease cases stand to increase with a hotter planet, and how warmer weather triggers a chain reaction of changes in delicately calibrated ecosystems. When the weather is warmer, the breeding cycles of the mosquitoes shorten, which means the bugs can reproduce multiple times instead of once or twice.  Heat also speeds up the incubation of the dengue virus inside the bugs, so it becomes infective much faster, which means it has a longer window in which to sicken someone during its three-to-four week life span. Plus, female mosquitoes bite more frequently when it’s hotter, boosting the capacity to transmit the virus.

Over the past half-century, dengue’s incidence has spiked 30-fold, according to the World Health Organization, and it now causes an estimated 50 million to 100 million infections annually in more than 100 countries. Rising temperatures have created an incubator for transmission because the mosquitoes that spread dengue are now able to survive in places that were once too cold. Epidemic outbreaks through Central and South America and the Caribbean, in Brazil, Mexico, Honduras, Paraguay and Cuba, now affect up to a million people every year, especially in densely populated and developing megacities in the tropical belt.

In the upcoming weeks, I’ll also address how heat waves and fires can become a toxic mix; what happens to the public health system after natural disasters; the long lasting effects of malnutrition and famine on the next generation; how increasingly foul air is causing permanent developmental damage and deaths; super-charged hoodlum weeds and the skyrocketing rates of allergies and asthma; and what smart cities are doing to smooth the transition to a hotter, dryer future.    

Linda Marsa's book FEVERED will be available on August 6, 2013, wherever books and e-books are sold.