One of the perks of my job is answering emails from high school and junior high students doing their first research projects on climate change science, policy, and politics.
A little while back, I got an email from a 14 year-old Virginia middle-schooler named Emily, who was working on a debate project about global warming. She asked me the six good questions below, and I thought I'd answer them via this post. But first, my apologies to Emily for taking so long - her debate probably has already taken place. I hope these responses will help some other students with their assignments.
- As an environmentalist, what actions do you go out of your way to take to on a regular basis to help out the environment?
Emily, our personal choices and habits matters. Mine aren't perfect, but here are a few things I do and don't do. I drive a hybrid car, and I bike to work when the weather is mild (good exercise). In our home, I have installed energy-efficient heating and cooling systems, EnergyStar appliances (like our refrigerator and dishwasher) and energy-efficient LED and compact fluorescent lights. All those things help us use less energy, and using less energy creates less pollution--less carbon emissions from burning gasoline in our car, and less carbon emissions from burning coal and natural gas in the power plants that supply electricity to our house. I'm also a regular recycler, which the city's once-a-week pick-up makes easy--it takes just a fraction of the energy to make new cans from old empties, and to make new newsprint from yesterday's papers. Using less energy means we put less carbon pollution into our atmosphere, warming the planet and disturbing our fragile climate system.
Individual consumers have a lot of power, and when they demand more efficient cars, lighting, appliances, etc., companies respond by making those products. But we're all busy doing our day jobs, and taking care of our families or going to school - and just looking for an hour a day to relax. It's too much to ask everyone to bone up on what's the most efficient product, and to do the dollars-and-cents calculations about whether the payback in lower gasoline or electric bills makes the extra front-end cost for this or that product worthwhile.
That's why it makes sense to have energy efficiency standards that make it easier for people to protect their pocketbooks and the earth we all depend on. Let me give you an example: Energy-efficient light bulbs can help us save a huge amount of electricity and money. Still, for decades, the lighting industry kept making the same kind of bulbs that Thomas Edison invented more than 100 years ago. And those bulbs waste most of their energy making heat, rather than light.
So in 2007, Congress passed the Energy Independence and Security Act that set efficiency standards for light bulbs, with support from both Democratic and Republican representatives in Congress, and from President George W. Bush, who signed the bill into law. Companies have responded by making LED and other kinds of bulbs, in every shape and size, that give off just as much light for a fraction of the electricity. (They don't waste power turning it into useless heat.) The lightbulb standards in this law will save Americans a total of $13 billion a year and avoid the amount of pollution that would have poured out of 30 large power plants. And the light they produce - for a lot less electricity - is just as pleasing as from Edison's old incandescent bulb.
Same story for our cars. In recent years, under the Clean Air Act and the Energy Independence law mentioned above, the federal government has set standards for new cars that will double how far they go on a gallong of gas and cut their carbon pollution in half -- all while saving car owners thousands of dollars at the pump.
That's how our clean air and clean energy laws can help us go beyond our individual actions, to help out the environment and save money at the same time.
- What would make you change your beliefs on global warming--make you believe it is a natural process or not a problem to be dealt with?
I gotta go with scientists. You hear from some TV pundits and politicians that the science is uncertain, or that global warming is an out-and-out hoax. But I listen to the climate scientists. More than 97 percent of the world's climate scientists tell us that by polluting the atmosphere with carbon dioxide, methane and other greenhouse gases, we're heating up the planet and changing our climate.
One of the best summaries of climate science comes from the American Association for the Advancement of Science - the publishers of this country's pre-eminent science magazine, Science. Their summary of climate science is called What We Know: The Reality, Risks and Response to Climate Change..
And we don't have the opportunity for do-overs. Unlike ordinary air pollutants, which disappear from the air in just a few days, carbon dioxide and other heat-trapping pollutants stick around in the atmosphere for very long times. Carbon dioxide, for example, stays there for more than 100 years. It just keeps building up, like continuing to fill a bathtub with a really slow drain. Which means your generation will have to live not only with the carbon pollution you emit in your lifetime, but also with the pollution your parents and grandparents put up there too.
Bottom line: Climate scientists are as sure that carbon pollution causes global warming as medical scientists are sure that smoking causes cancer. And increasingly, climate scientists are getting really alarmed. They know time is running out to head off the worst impacts, and they are as frustrated as can be by the political forces that keep the public confused.
So, to answer your question: If the vast majority of climate scientists were to say these changes weren't happening, or were just part of a natural process, I would believe them. Unfortunately, that's not what they say.
Here's the good news, though: If we act now, there are still lots of things we can do to help protect your generation, and the ones to follow you, from the worst impacts.
- What will be the harshest effects of global warming in the future? In how long will these effects take place?
Emily, it's hard to say which effects of global warming will be the harshest. They all sound pretty bad--increased heat waves, wildfires and droughts. More severe hurricanes. Disruptions to agriculture, making food more scarce and expensive. The poorest countries and the poorest people are already suffering the most. But impacts are already happening everywhere, and all of us will feel climate change's effects.
And in this interconnected world, the poorest countries don't suffer in isolation. When a hurricane hits the Philippines, we see it on TV, and it touches us all. But it's not just on our TV screens. The Pentagon has identified climate change as a "threat multiplier," because it undermines countries' stability and aggravates the conditions that in too many places lead to refugee crises, civil unrest, and even war. Leading scholars and journalists, such as Tom Friedman of the New York Times, argue that higher grain prices, brought about by droughts and floods in places as remote as Russia and Australia, helped trigger the unrest across the Middle East that we call the Arab Spring.
If we keep polluting at our current rate, over the next several decades, when you'll be in the prime of your life, we'll see a lot more climate disruption. That's why groups like NRDC are working hard at the national, state, local, and international level to make sure governments, businesses, and people everywhere change course--cut pollution, stop cutting down the world's really important forests, and move to cleaner energy. There's still a lot we can do to prevent the most terrible effects.
- What are the most crucial steps to change the temperature of the globe?
The most important thing we can do to keep global temperatures down is to cut the carbon dioxide pollution that comes from burning fossil fuels like coal, oil, and natural gas for electric power, transportation, and industry. Here in the U.S., nearly 40 percent of our global warming pollution comes just from power plants, and another 20 percent from our cars. That's why the EPA's Clean Car Standards and its Clean Power Plan are so important. These are the biggest things we can do right now to cut carbon pollution.
There are lots of great ways to cut power plant pollution. Energy efficiency--using less energy to do the same stuff, like those energy-efficient light bulbs we talked about--is one of them. Here in the U.S., we waste a mind-blowing 60 percent of the energy we use, scientists at Lawrence Berkeley National Laboratory have calculated. We've got the technology and the know-how to do a lot better.
Switching to renewable energy, like wind and solar power, is another great way to keep the earth's temperature down, because wind and solar power don't add to the pollution in our atmosphere.
It's also important to cut down on the amount of methane--the main component of natural gas--that leaks into our air from the pipelines and other oil and gas equipment that brings natural gas to our houses. And that we replace refrigerants called HFCs with new coolants that, when they leak into the air, don't contribute to more climate change. Recently, President Obama announced proposals to get started on both those things. But there's more to do.
Saving forests is extremely important, too. Right now, deforestation--the cutting down of forests--is responsible for 15 percent of the world's greenhouse gas pollution. (When trees are cut down, most of the carbon they contain gets released into the atmosphere.)
- What is the best-supported evidence global warming is taking place and is caused by humans?
You can get the low-down on the science from the What We Know publication I mentioned earlier. It draws on the world's best reports, like those of the Intergovernmental Panel on Climate Change, and the U.S. National Academy of Sciences.
This is not something we discovered only yesterday. Scientists first discovered that carbon dioxide and other greenhouse gases trap heat in our atmosphere in the mid-1800s, before the Civil War. And 50 years ago, President Lyndon Johnson first called on us to curb the carbon dioxide pollution that's causing climate change. Since then, the evidence that global warming is happening and caused by human activity has become so overwhelming that the Intergovernmental Panel on Climate Change, the most authoritative group of scientists from around the world, has said "scientific evidence for warming of the climate system is unequivocal." In other words, science has proved, beyond a reasonable doubt, that global warming is definitely happening and we're causing it.
The climate changes we've witnessed in the last 30 years can't be explained by computer models that describe normal weather patterns and temperatures. Only when greenhouse gas concentrations are factored in do the computer models reproduce the changes scientists and regular people observe.
- Because of how far global warming has gotten, will there be a way to reverse its effects completely? Will we only be able to slow it down? How much time will this take?
Unfortunately, even if we stopped polluting the atmosphere overnight, it would still take a very long time to completely reverse climate change's effects--perhaps a thousand years, given the technologies and natural processes available to us now. As I explained, once in the atmosphere carbon dioxide emissions stay there for more than 100 years, soaking up heat every day. Scientists are researching ways to pull carbon dioxide from the atmosphere. The current best technology for doing that is reforestation--planting new forests. Maybe we can improve on that.
For now, the best thing we can do is to start cutting our carbon pollution now, and transitioning to a clean energy future. That's why NRDC wants to ramp up the use of clean energy and pollution-free cars and trucks fast, both here in the U.S. and around the world. The less pollution we put in the atmosphere now, the more we can slow down the impacts, and the more time we'll have to come up with better ways to get rid of the stuff.
* * *
Emily, I'm so glad you wrote and I hope these answers help other students -- even if they came too late for your debate. There'll be many more chances for you to debate global warming, and what to do about it.