OUR CHANGING CLIMATE

Is human-caused climate change real?  If so, does it adversely affect Riverwoods?  And if so, what can we do?

The Earth’s climate has changed throughout history, mostly attributable to small variations in the Earth’s orbit or in solar radiation and other natural cycles.  The current warming trend is different. Human activities such as burning fossil fuels, cultivating crops, raising livestock, and clearing forests are releasing greenhouse gases into the atmosphere.  This increase in the amount of greenhouse gases has been rapid. The atmospheric concentration of carbon dioxide has increased by more than 40% over the last few hundred years following the widespread use of coal and petroleum as fuel.  Chemical fingerprinting indicates human activity as the cause.

FIRST, WHAT IS “CLIMATE CHANGE”?

IT’S REAL.  Scientists specializing in climate science are almost unanimous on the subject.  Based on their research, about 97% of climate scientists believe human-caused climate change exists and that it’s adversely affecting our planet.  Yes, there are contrarians. Few of them are climate scientists; they’re meteorologists, astrophysicists or others not directly involved in the rigorous study of climate.  The fact that most climate scientists believe human-caused climate change exists, and the breadth of their evidence, is compelling.

The current level of atmospheric carbon dioxide is higher than it has been in at least 800,000 years.  Ice cores from Greenland, Antarctica, and various glaciers show that the Earth’s climate is responding to changes in greenhouse gas levels.  Corroboration is found in tree rings, ocean sediments, coral reefs, and sedimentary rocks.

Evidence of the Earth’s adverse response to this higher level of carbon dioxide includes:

  • current warming is roughly 10 times faster than the average warming following the ice age
  • sea levels have risen approximately 6.7 inches in the last century, about double from the prior century  
  • global surface temperatures – air and water – have risen since 1880, and especially since the 1950’s
  • ice sheets and sea ice have been shrinking rapidly
  • ocean acidification has been increasing

Most warming has occurred in the last 35 years, and 16 of the 17 warmest years on record have occurred since 2001.  The year 2016 was the warmest year on record globally – the third year in a row to set a new warming record. However, it’s important to understand that climate change is not simply global warming.  It’s climate disruption – some areas getting warmer, some cooler, some wetter and some drier. And it’s climate unpredictability, with increasing storm events. Climate change affects housing, agriculture (and thus food supplies), and all species of animals and plants on the planet.

IT’S A BIG PROBLEM.   The Earth is very sensitive to even small temperature changes.  The global temperature during the last ice age was only 5 to 9 degrees F. cooler than today.  Even a few degrees increase in the planet’s average temperature can result in large changes in local climate, creating risks to public safety, health, water resources, and food sources.  The climate process is global, but the effects are regional.

More extreme weather is becoming the norm, with more frequent storms, flooding and droughts.  Heat waves have become more frequent and prolonged in the US, drying soil and challenging agriculture.  Extreme temperatures degrade air quality, aggravating respiratory and cardiovascular problems. Warmer temperatures create a more hospitable environment for food and water-borne pathogens and for disease-causing insects such as mosquitoes and ticks.  Wildfires have increased. Everyone will be impacted by increasing global warming, especially the most vulnerable groups such as the young, the elderly, and those living in poverty.

Because carbon dioxide remains in the atmosphere for hundreds or thousands of years, the climate will continue to warm for at least the next several decades, regardless of what we do.  Many climate scientists believe we are rapidly approaching a climate tipping point, beyond which further change will accelerate regardless of what we do. In that circumstance, they predict that humans will have great difficulty adapting.  

WHAT CAN WE DO?  Climate scientists tell us that it’s imperative to substantially reduce greenhouse gas emissions.  To do so will require greater energy efficiency, shifting to cleaner energy sources, significant waste reduction, and slowing deforestation.  In addition, communities must identify local vulnerabilities and incorporate climate change into planning and development.

CARBON FOOTPRINT CALCULATION.  The U.S. Environmental Protection Agency (EPA) website includes an interactive carbon footprint calculator (https://www3.epa.gov/carbon-footprint-calculator/) that allows people to estimate the carbon footprints in their homes and on the road, and to compare individual footprints to US averages.  The website includes suggestions for improvement and allows people to estimate how changes in lifestyle would affect their carbon footprint, e.g., increasing recycling or changing thermostat settings.   An additional tool for calculating your carbon footprint is www.carbonindependent.org.  (For an analysis of several carbon calculator tools, see http://www.ethicalconsumer.org/default.aspx?TabId=422.)   4/17