The problem: Carbon pollution is fueling global warming

 The science of global warming starts with the burning of fossil fuels, specifically in vehicles fueled by Big Oil and at coal-fired power plants owned by companies like Constellation Energy.  When we burn fossil fuels like coal, oil or natural gas, carbon dioxide is emitted into the air.  This carbon pollution collects in the atmosphere, where it traps heat from the sun that would otherwise escape into space.  That causes the earth’s temperature to rise, which triggers a variety of mostly negative results for Maryland and the planet. 

And temperatures are definitely rising.  Already, March 2012 was the hottest March on record for the continental U.S., 2010 tied for the hottest year, and the decade of 2001-2010 was the hottest 10-year period on record.  The evidence that humans are warming the globe is only strengthening; in the words of a recent report from the U.S. National Academy of Sciences: “Some scientific conclusions or theories have been so thoroughly examined and tested, and supported by so many independent observations and results, that their likelihood of subsequently being found to be wrong is vanishingly small…This is the case for the conclusion that the Earth system is warming and that much of this warming is very likely due to human activities.”    

The results: Extreme weather, air pollution and more

As the planet warms, experts warn that Maryland will likely experience a variety of negative consequences:

•    Extreme storms & hurricanes:  Higher temperatures lead to more major rainstorms and heavy snowstorms for two reasons.  First, warmer temperatures lead to greater evaporation, so more water in our lakes and oceans becomes airborne.  Second, warmer air can hold more water vapor.  This means that when it rains, the atmosphere will have more moisture to work with and so heavy downpours and more intense hurricanes are more likely—as is more of the flooding that often results from these storms.  Already, the number of extreme precipitation events increased 24 percent over the continental U.S. between 1948 and 2006, and at least 14 weather-related disasters causing at least $1 billion in damage hit the U.S. in 2011 alone, many of which involved devastating floods. 

•    Smog pollution:  Ozone “smog” pollution is the pollution that hangs over our cities on many of the hottest summer days.  Since heat is a key ingredient in the formation of smog (pollution from cars, trucks and power plants is the other), which triggers asthma attacks and a variety of other respiratory problems, scientists predict that we’ll see even more smog in a warming world.  In fact, a study by the Union of Concerned Scientists predicts that higher levels of ground-level ozone due to rising temperatures in 2020 could lead to 2.8 million more asthma attacks and other respiratory problems, leading to 900,000 additional missed days of school. That’s bad news for all of us, but especially the 322,649 adults and 139,336 kids in Maryland who suffer from asthma.

•    Heat waves: Just as we can expect average temperatures to rise in a warming world, we can also expect to see more intense and longer-lasting heat waves in Maryland and across the country. Winter in 2012 was peppered with strangely warm days, many of which reached 80 degrees. These heat waves can threaten the health and well-being of even healthy individuals, as happened in 2011 when at least six high school football players and one coach died during or shortly after practices held in southern states during a period of extreme summer heat.  

•    Drought: Even though we’re likely to see more precipitation fall when it does rain or snow, it’s also the case that a warming world will likely result in longer dry spells in between rainfalls for some parts of the country.  Combined with high temperatures, these dry spells can lead to drought.  During the second half of the 20th century, drought became more common in parts of the northern Rockies, the Southwest and the Southeast, and less common in parts of the northern Plains and Northeast.  Droughts can wreak havoc in many ways, from lower crop yields for farmers to the threat of dangerous wildfires.

•    Sea level rise: As warming temperatures cause a thermal expansion of sea water as well as the melting of glaciers and ice caps, sea level rises.  Sea level has risen by nearly 8 inches since 1870, with the rate of sea level rise increasing in recent years.  One recent study projects that by 2100 the rise could reach between 2.5 and 6 feet.  This rise in sea level not only threatens to inundate the many low-lying communities and thousands of acres of land along our coasts and tidally influenced rivers, but also increase the punch packed by hurricanes and other coastal storms. Sea level is expected to rise by more than a foot in Maryland by 2050 and potentially by 3.4 feet by the end of the century, which could submerge hundreds of square miles of land.

The solution: Cut carbon pollution, promote clean energy

Thankfully, we know what we have to do to slow and stop global warming.  To give ourselves the best chance of protecting future generations from the worst consequences of global warming, scientists have said the U.S. and other developed countries need to cut our carbon emissions so that by 2020 we’re emitting 25-40 percent less carbon into the air than we were in 1990.  

That’s a steep goal, but in Maryland and across the country, we’re already starting to move in the right direction.  We know we can reduce emissions of the carbon pollution by cutting down on energy waste through energy efficiency measures, and developing cleaner, renewable energy sources like wind and solar power.  We can make our buildings much more energy efficient so that they’re demanding less energy from coal-fired power plants.  We can make our cars go farther on a gallon of gas, and expand public transportation systems so that more people can get where they’re going without using their cars at all. Here in Maryland, a state law passed in 2009 requires the state to slash global warming pollution by 2020. The law’s centerpiece specified that by the end of 2012, Maryland agencies were required to come up with a plan and comprehensive regulatory framework to achieve ambitious reductions.

Together, all of these things add up.  A recent Environment Maryland Research & Policy Center report, The Way Forward on Global Warming, found that by adopting a suite of clean energy policies at the local, state and federal levels, the U.S. could reduce carbon emissions by as much as 20 percent by 2020 and 34 percent by 2030 (compared to 2005 levels)—representing a significant down payment toward the pollution reductions called for by scientists.