Q: What is global warming?
A: Here's a simple definition of global warming. (And yes, it's really happening.) Over
the past 50 years, the average global temperature has increased at the fastest rate in
recorded history. And experts see the trend is accelerating: All but one of the 16 hottest
years in NASA’s 134-year record have occurred since 2000.
Climate change deniers have argued that there has been a “pause” or a “slowdown” in
rising global temperatures, but several recent studies, including a 2015 paper published
in the journal Science, have disproved this claim. And scientists say that unless we curb
global-warming emissions, average U.S. temperatures could increase by up to 10
degrees Fahrenheit over the next century.
Q: What causes global warming?
A: Global warming occurs when carbon dioxide (CO2) and other air pollutants and
greenhouse gases collect in the atmosphere and absorb sunlight and solar radiation
that have bounced off the earth’s surface. Normally, this radiation would escape into
space—but these pollutants, which can last for years to centuries in the atmosphere,
trap the heat and cause the planet to get hotter. That's what's known as the greenhouse
effect.
In the United States, the burning of fossil fuels to make electricity is the largest source
of heat-trapping pollution, producing about two billion tons of CO2 every year. Coal-
burning power plants are by far the biggest polluters. The country’s second-largest
source of carbon pollution is the transportation sector, which generates about 1.7 billion
tons of CO2 emissions a year.
Curbing dangerous climate change requires very deep cuts in emissions, as well as the use of
alternatives to fossil fuels worldwide. The good news is that we’ve started a turnaround: CO2
emissions in the United States actually decreased from 2005 to 2014, thanks in part to new,
energy-efficient technology and the use of cleaner fuels. And scientists continue to develop new
ways to modernize power plants, generate cleaner electricity, and burn less gasoline while we
drive. The challenge is to be sure these solutions are put to use and widely adopted.
Q: How is global warming linked to extreme weather?
A: Scientists agree that the earth’s rising temperatures are fueling longer and hotter
heat waves, more frequent droughts, heavier rainfall, and more powerful hurricanes. In
2015, for example, scientists said that an ongoing drought in California—the state’s
worst water shortage in 1,200 years—had been intensified by 15 percent to 20 percent
by global warming. They also said the odds of similar droughts happening in the future
had roughly doubled over the past century. And in 2016, the National Academies of
Science, Engineering, and Medicine announced that it’s now possible to confidently
attribute certain weather events, like some heat waves, directly to climate change.
The earth’s ocean temperatures are getting warmer, too—which means that tropical
storms can pick up more energy. So global warming could turn, say, a category 3 storm
into a more dangerous category 4 storm. In fact, scientists have found that the
frequency of North Atlantic hurricanes has increased since the early 1980s, as well as
the number of storms that reach categories 4 and 5. In 2005, Hurricane Katrina—the
costliest hurricane in U.S. history—struck New Orleans; the second-costliest, Hurricane
Sandy, hit the East Coast in 2012.
The impacts of global warming are being felt across the globe. Extreme heat waves
have caused tens of thousands of deaths around the world in recent years. And in an
alarming sign of events to come, Antarctica has been losing about 134 billion metric
tons of ice per year since 2002. This rate could speed up if we keep burning fossil fuels
at our current pace, some experts say, causing sea levels to rise several meters over
the next 50 to 150 years.
Q: What are the other effects of global warming?
A: Each year, scientists learn more about the consequences of global warming, and
many agree that environmental, economic, and health consequences are likely to occur
if current trends continue. Here’s just a smattering of what we can look forward to:
Melting glaciers, early snowmelt, and severe droughts will cause more dramatic water
shortages and increase the risk of wildfires in the American West.
Rising sea levels will lead to coastal flooding on the Eastern Seaboard, especially in
Florida, and in other areas such as the Gulf of Mexico.
Forests, farms, and cities will face troublesome new pests, heat waves, heavy downpours,
and increased flooding. All those factors will damage or destroy agriculture and fisheries.
Disruption of habitats such as coral reefs and Alpine meadows could drive many plant and
animal species to extinction.
Allergies, asthma, and infectious disease outbreaks will become more common due to
increased growth of pollen-producing ragweed, higher levels of air pollution, and the
spread of conditions favorable to pathogens and mosquitoes.
Causes
Water vapor. The most abundant greenhouse gas, but importantly, it acts as a
feedback to the climate. Water vapor increases as the Earth's atmosphere
warms, but so does the possibility of clouds and precipitation, making these
some of the most important feedback mechanisms to the greenhouse effect.
Carbon dioxide (CO2). A minor but very important component of the atmosphere,
carbon dioxide is released through natural processes such as respiration and
volcano eruptions and through human activities such as deforestation, land use
changes, and burning fossil fuels. Humans have increased atmospheric
CO2 concentration by more than a third since the Industrial Revolution began.
This is the most important long-lived "forcing" of climate change.
Methane. A hydrocarbon gas produced both through natural sources and human
activities, including the decomposition of wastes in landfills, agriculture, and
especially rice cultivation, as well as ruminant digestion and manure
management associated with domestic livestock. On a molecule-for-molecule
basis, methane is a far more active greenhouse gas than carbon dioxide, but also
one which is much less abundant in the atmosphere.
Nitrous oxide. A powerful greenhouse gas produced by soil cultivation practices,
especially the use of commercial and organic fertilizers, fossil fuel combustion,
nitric acid production, and biomass burning.
Chlorofluorocarbons (CFCs). Synthetic compounds entirely of industrial origin
used in a number of applications, but now largely regulated in production and
release to the atmosphere by international agreement for their ability to contribute
to destruction of the ozone layer. They are also greenhouse gases.
Effects
Global climate change has already had observable effects on the environment.
Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal
ranges have shifted and trees are flowering sooner.
Effects that scientists had predicted in the past would result from global climate
change are now occurring: loss of sea ice, accelerated sea level rise and longer,
more intense heat waves.
Solutions
Nations around the world are upping their game in the fight against climate change,
even as President Trump recently announced the U.S.'s withdrawal from the Paris
Agreement. And despite this reckless move, American mayors, state leaders, county
officials, governors, major companies, and millions of citizens across our country have
pledged that they're "still in" when it comes to the agreement, and supporting the goal of
limiting future warming to well below 2 degrees Celsius.
Even better, a new initiative by former New York City mayor Michael Bloomberg gives
the urban layer of this movement a boost. He’s asked mayors from the 100 most
populous cities in the country to share their plans for making their buildings and
transportation systems run cleaner and more efficiently. The 20 that show the greatest
potential for cutting the dangerous carbon pollution that’s driving climate change will
share a total of $70 million in technical assistance funding provided by Bloomberg
Philanthropies and partners.
It’s important to remember the equally vital contributions that can be made by private
citizens—which is to say, by you. “Change only happens when individuals take
action,” Aliya Haq, deputy director of NRDC’s Clean Power Plan initiative, says.
“There’s no other way, if it doesn’t start with people.”
The goal is simple. Carbon dioxide is the climate’s worst enemy. It’s released when oil,
coal, and other fossil fuels are burned for energy—the energy we use to power our
homes, cars, and smartphones. By using less of it, we can curb our own contribution to
climate change while also saving money. Here are a dozen easy, effective ways each
one of us can make a difference:
1. Speak up!
What’s the single biggest way you can make an impact on global climate change? “Talk
to your friends and family, and make sure your representatives are making good
decisions,” Haq says. By voicing your concerns—via social media or, better yet, directly
to your elected officials—you send a message that you care about the warming world.
Encourage Congress to enact new laws that limit carbon emissions and require
polluters to pay for the emissions they produce. “The main reason elected officials do
anything difficult is because their constituents make them,” Haq says. You can help
protect public lands, stop offshore drilling, and more here.
2. Power your home with renewable energy.
Choose a utility company that generates at least half its power from wind or solar and
has been certified by Green-e Energy, an organization that vets renewable energy
options. If that isn’t possible for you, take a look at your electric bill; many utilities now
list other ways to support renewable sources on their monthly statements and websites.
3. Weatherize, weatherize, weatherize.
“Building heating and cooling are among the biggest uses of energy,” Haq says. Indeed,
heating and air-conditioning account for almost half of home energy use. You can make
your space more energy efficient by sealing drafts and ensuring it’s adequately
insulated. You can also claim federal tax credits for many energy-efficiency home
improvements.
4. Invest in energy-efficient appliances.
Since they were first implemented nationally in 1987, efficiency standards for dozens of
appliances and products have kept 2.3 billion tons of carbon dioxide out of the air.
That’s about the same amount as the annual carbon pollution coughed up by nearly 440
million cars. “Energy efficiency is the lowest-cost way to reduce emissions,” Haq says.
When shopping for refrigerators, washing machines, and other appliances, look for
the Energy Star label. It will tell you which are the most efficient.
5. Reduce water waste.
Saving water reduces carbon pollution, too. That's because it takes a lot of energy to
pump, heat, and treat your water. So take shorter showers, turn off the tap while
brushing your teeth, and switch to WaterSense-labeled fixtures and appliances. The
EPA estimates that if just one out of every 100 American homes were retrofitted with
water-efficient fixtures, about 100 million kilowatt-hours of electricity per year would be
saved—avoiding 80,000 tons of global warming pollution.
6. Actually eat the food you buy—and make less of it meat.
Approximately 10 percent of U.S. energy use goes into growing, processing, packaging,
and shipping food—about 40 percent of which just winds up in the landfill. “If you’re
wasting less food, you’re likely cutting down on energy consumption,” Haq says. And
since livestock products are among the most resource-intensive to produce, eating
meat-free meals can make a big difference, too.
7. Buy better bulbs.
LED lightbulbs use up to 80 percent less energy than conventional incandescents.
They’re also cheaper in the long run: A 10-watt LED that replaces your traditional 60-
watt bulb will save you $125 over the lightbulb’s life.
8. Pull the plug(s).
Taken together, the outlets in your home are likely powering about 65 different
devices—an average load for a home in the U.S. Audio and video devices, cordless
vacuums and power tools, and other electronics use energy even when they're not
charging. This "idle load" across all U.S. households adds up to the output of 50 large
power plants in the U.S.So don't leave fully charged devices plugged into your home's
outlets, unplug rarely used devices or plug them into power strips and timers, and adjust
your computers and monitors to automatically power down to the lowest power mode
when not in use.
9. Drive a fuel-efficient vehicle.
Gas-smart cars, such as hybrids and fully electric vehicles, save fuel and money. And
once all cars and light trucks meet 2025’s clean car standards, which means averaging
54.5 miles per gallon, they’ll be a mainstay. For good reason: Relative to a national fleet
of vehicles that averaged only 28.3 miles per gallon in 2011, Americans will spend $80
billion less at the pump each year and cut their automotive emissions by half. Before
you buy a new set of wheels, compare fuel-economy performance here.
10. Maintain your ride.
If all Americans kept their tires properly inflated, we could save 1.2 billion gallons of gas
each year. A simple tune-up can boost miles per gallon anywhere from 4 percent to 40
percent, and a new air filter can get you a 10 percent boost.
11. Rethink planes, trains, and automobiles.
Choosing to live in walkable smart-growth cities and towns with quality public
transportation leads to less driving, less money spent on fuel, and less pollution in the
air. Less frequent flying can make a big difference, too. “Air transport is a major source
of climate pollution,” Haq says. “If you can take a train instead, do that.”
12. Shrink your carbon profile.
You can offset the carbon you produce by purchasing carbon offsets, which represent
clean power that you can add to the nation’s energy grid in place of power from fossil
fuels. But not all carbon offset companies are alike. Do your homework to find the best
supplier.
Change a light
Replacing one regular light bulb with a compact fluorescent light bulb will save 150
pounds of carbon dioxide a year.
Drive less
Walk, bike, carpool or take mass transit more often. You'll save one pound of carbon
dioxide for every mile you don't drive!
Recycle more
You can save 2,400 pounds of carbon dioxide per year by recycling just half of your
household waste.
Check your tires
Keeping your tires inflated properly can improve your gas mileage by more than 3
percent. Every gallon of gasoline saved keeps 20 pounds of carbon dioxide out of the
atmosphere.
Use less hot water
It takes a lot of energy to heat water. Use less hot water by taking shorter and cooler
showers and washing your clothes in cold or warm instead of hot water (more than 500
pounds of carbon dioxide saved per year).
Avoid products with a lot of packaging
You can save 1,200 pounds of carbon dioxide if you reduce your garbage by 10
percent.
Adjust your thermostat
Moving your thermostat down just 2 degrees in winter and up 2 degrees in summer
could save about 2,000 pounds of carbon dioxide a year.
Plant a tree
A single tree will absorb one ton of carbon dioxide over its lifetime.
Turn off electronic devices
Simply turning off your television, DVD player, stereo, and computer, when you're not
using them, will save you thousands of pounds of carbon dioxide a year.
Ice ages are prominent examples. Climate change is any significant long-termchange in the
expected patterns of average weather of a region (or the whole Earth) over a significant period
of time. Climate change is about abnormal variations to theclimate, and the effects of these
variations on other parts of the Earth.
How Do Humans Contribute to Global Climate Change?
Throughout most of human history, and certainly, before human beings emerged
as a dominant species throughout the world, all climate changes were the direct
result of natural forces like solar cycles and volcanic eruptions. Along with
the Industrial Revolution and an increasing population size, humans began
altering climates with ever-growing influence, and eventually surpassed natural
causes in their ability to change the climate. Human-caused global climate
change is primarily due to the release, through our activities, of greenhouse
gases.
Greenhouse gases are released into the air, where they persist for a long period at
high altitude and absorb reflected sunlight. They then warm the atmosphere, the
surface of the land, and the oceans. Many of our activities contribute greenhouse
gases to the atmosphere.
Fossil Fuels Carry Much of the Blame
The process of burning fossil fuels releases various pollutants, as well as an
important greenhouse gas, carbon dioxide. We know that the use of gasoline and
diesel to power vehicles is a large contributor, but overall transportation only
accounts for approximately 14% of total greenhouse gas emissions. The single
largest culprit is electricity production by coal, gas, or oil-burning power plants,
with 20% of all emissions.
It's Not Only About Power and Transportation
The various industrial processes that use fossil fuels are also to blame. For
example, large quantities of natural gas are needed to produce the synthetic
fertilizers used in conventional agriculture.
Just the process of extracting and processing coal, natural gas, or oil involves the
release of greenhouse gases -- those activities make up 11% of the total emissions.
This includes natural gas leaks during the extraction, transportation, and delivery
phases.
Non-Fossil Fuel Greenhouse Gas Emissions
Cement production hinges on a chemical reaction that releases massive
amounts of carbon dioxide.
Land clearing (for agriculture or other types of land use) exposes the soil
which allows the release of carbon dioxide.
Deforestation, especially associated with burning, allows a lot of the carbon
stored in tree roots, branches, and leaves to be released into the
atmosphere. It's not a trivial amount: together, land clearing and burning
account for 10% of all greenhouse gas emissions.
Methane (the main constituent in natural gas) is produced in large
quantities by microorganisms present in rice fields, making rice production
a significant contributor to climate change. And it's not just rice: lots of
methane is also produced by cattle and other herbivorous livestock.
Temperatures are warming especially fast in Arctic regions, and there the
thawing permafrost is releasing both carbon dioxide and
methane. By 2100, it is estimated that 16 to 24% of the permafrost will
have thawed, entering a vicious feedback loop: as permafrost thaws, it
releases stored carbon dioxide and methane, which further warms the
climate, melts more permafrost and releases more greenhouse gases.
Just as we create greenhouse gases, we can also take steps to reduce those
emissions. It should become clear from reading this list that a whole suite of
solutions is necessary to tackle climate change, beginning with the switch to
renewable energy. Responsible stewardship also means encouraging sustainable
agricultural and forestry practices.
How to outline
Example of Topic Outline
Several aspects must be considered in writing a topic outline.
Recall that all headings and subheadings must be words or phrases, not sentences.
Also, the wording within each division must be parallel.
Finally, as in any outline, remember that a division or subdivision cannot be divided into one
part; therefore, if there is an "A" there must be a "B," and if there is a "1" there must be a "2."
I. Family Problems
A. Custodial: Non-custodial Conflicts
B. Extended Family
C. Adolescent's Age
II. Economic Problems
A. Child Support
B. Women's Job Training
C. Lower Standard of Living
D. Possible Relocation
1. Poorer Neighborhood
2. New School
III. Peer Problems
A. Loss of Friends
B. Relationships with Dates
Topic OutlineExample: Thesis:
The abuse of alcohol and drugs
can affect a person
economically, psychologically,
and physically. I. Economical
effects (Main idea) A. Alcohol
(Sub-idea) 1. Cost of alcohol
purchases (Detail of A) 2. Cost
of DUIs (Detail of A) B. Drugs
(Sub-point) 1. Cost of drug
purchases (Detail of B) 2. Cost
of drug arrest (Detail of B) II.
Psychological effects A.
Alcohol 1. Mental impairment
2. Mental addiction B. Drugs 1.
Mental impairment 2. Mental
addiction III. Physical effects A.
Alcohol 1. Liver disease 2.
Alcohol poisoning B. Drugs 1.
Brain damage 2. Drug overdose
