Step 1: Read & annotate each of the 3 following
articles
Step 2: Re-read, then summarize and list the
main points of each article in the table on page
4 (You may draw your own table, or print page 4 ONLY)
Article 1
Today's Climate Change
More than 100 years ago, people around the world started burning large amounts of coal, oil, and
natural gas to power their homes, factories, and vehicles. Today, most of the world relies on these
fossil fuels for their energy needs. Burning fossil fuels releases carbon dioxide, a heat-trapping gas,
into the atmosphere, which is the main reason why the climate is changing.
Heat-trapping gases are also called greenhouse gases. They exist naturally in the atmosphere, where
they help keep the Earth warm enough for plants and animals to live. But people are adding extra
greenhouse gases to the atmosphere. These extra gases are causing the Earth to get warmer, setting
off all sorts of other changes around the world—on land, in the oceans, and in the atmosphere. And these
changes affect people, plants, and animals in many ways.
Learn more about carbon dioxide and other greenhouse gases and how they are changing the Earth's
climate:
Article 2:
The Earth's Climate in the Past:
Today's Climate Change Is Different!
Today's climate change is different from past climate change in several important ways:
1.
2.
3.
Natural causes are not responsible.None of the natural causes of climate change, including variations in the sun's energy and
the Earth's orbit, can fully explain the climate changes we are seeing today.
People's activities are the main cause. By burning lots of fossil fuels like coal, oil, and natural gas, people are overloading
the atmosphere with carbon dioxide and adding to the greenhouse effect. People are also adding other heat–trapping greenhouse
gases, such as methane and nitrous oxide, to the atmosphere.
Greenhouse gases are at record levels in the atmosphere. For hundreds of thousands of years, the concentration of carbon
dioxide in the atmosphere stayed between 200 and 300 parts per million. Today, it's up to nearly 400 parts per million, and the
amount is still rising. Along with other greenhouse gases, this extra carbon dioxide is trapping heat and causing the climate to change.
The Earth was formed about 4.5 billion years ago—that's a very long time ago! It's hard to say exactly
what the Earth's daily weather was like in any particular place on any particular day thousands or
millions of years ago. But we know a lot about what the Earth's climate was like way back then because
of clues that remain in rocks, ice, trees, corals, and fossils.
These clues tell us that the Earth's climate has changed many times before. There have been times
when most of the planet was covered in ice, and there have also been much warmer periods. Over at
least the last 650,000 years, temperatures and carbon dioxide levels in the atmosphere have
increased and decreased in a cyclical pattern. Can you see this pattern in the graph below?
These graphs are based on the Vostok ice core from Antarctica. They do not include the most recent
increases in carbon dioxide and temperature caused by humans. Notice the strong connection between
carbon dioxide and temperature. Source: EPA's Climate Change Indicators (2010) and Petit et al. (2001).
People didn't cause the climate change that occurred thousands or millions of years ago, so it must
have happened for other natural reasons.
Scientists around the world agree that today's global climate change is mainly caused by people's activities.
Article 3:
Sun's Shifts May Cause Global Warming
FROM THE JULY 2007 ISSUE
Sun's Shifts May Cause
Global Warming
Physicist says carbon dioxide's no big deal
By Marion Long|Monday, June 25, 2007
Most leading climate experts don’t agree with Henrik Svensmark, the 49-year-old director
of the Center for Sun-Climate Research at the Danish National Space Center in Copenhagen.
In fact, he has taken a lot of blows for proposing that solar activity and cosmic rays are
instrumental in determining the warming (and cooling) of Earth. His studies show that
cosmic rays trigger cloud formation, suggesting that a high level of solar activity—which
suppresses the flow of cosmic rays striking the atmosphere—could result in fewer clouds
and a warmer planet. This, Svensmark contends, could account for most of the warming
during the last century. Does this mean that carbon dioxide is less important than we’ve
been led to believe? Yes, he says, but how much less is impossible to know because climate
models are so limited.
There is probably no greater scientific heresy today than questioning the warming role of
CO2, especially in the wake of the report issued by the United Nations Intergovernmental
Panel on Climate Change (IPCC). That report warned that nations must cut back on
greenhouse gas emissions, and insisted that “unless drastic action is taken . . . millions of
poor people will suffer from hunger, thirst, floods, and disease.” As astrophysicist ?Eugene
Parker, the discoverer of solar wind, writes in the foreword to Svensmark’s new book, The
Chilling Stars: A New Theory of Climate Change, “Global warming has become a political
issue both in government and in the scientific community. The scientific lines have been
drawn by ‘eminent’ scientists, and an important new idea is an unwelcome intruder. It
upsets the established orthodoxy.
NAME:______________________________________DATE:______PERIOD:__
Use the table below to list the main points from each article:
“Today’s Climate Change”
“Earth’s Climate in the
Past”
“Sun’s shifts may cause
global warming”
Conclusion: Using evidence from the articles, make an argument for what you
believe. Do you believe that the Sun’s activity is contributing to global warming?
(use links, below, if needed to help you)
Solution link: http://discovermagazine.com/2007/jul/the-discover-interview-henrik-svensmark#.UQwLx3AeSo
Link #2:
http://know.climateofconcern.org/index.php?option=com_content&t
ask=article&id=67