Transcript Climate Change in VERMONT - Vermont Agency of Natural

MODULE #2:
Climate Change &
Global Warming
…Science & Sources of Greenhouse
Gas (GHG) Emissions
Weather - the short term state of the atmosphere at a specific time
and place, including the temperature, humidity, cloud coverage,
precipitation, wind, etc.
Climate - the long-term “average weather” pattern of an area,
including temperature, precipitation, and wind.
Some useful definitions …
Climate Change - any long-term significant change in the “average
weather” that a given region experiences. These changes can be caused
by dynamic processes on Earth, external forces including variations in
sunlight intensity, and more recently by human activities.
Global warming - the increase in the average measured temperature of
the Earth's near-surface atmosphere and oceans since the mid-twentieth
century, and its projected continuation.
Is the Earth’s climate changing?
Yes, it is constantly changing due to natural forcings
(intensity of the sun, volcanic activity, etc.),
but more recently as a result of human activites.
Is the Earth getting warmer?
The United States recorded its
warmest year ever in 2006
2.2°F above the 20th Century ave.
2006
2007
Source: NASA
Yes.
The Earth’s
20 Hottest
Years on
Record
Source: Union of Concerned Scientists
Why is the Earth getting warmer ?
There is overwhelming evidence to show that
our climate is changing
in response to our actions!
•
Thousands of peer-reviewed scientific
research publications provide clear &
convincing evidence for warming caused
by humans (anthropogenic GHG
emissions)
•
Greenhouse Gas concentrations
have increased dramatically since
the industrial revolution. Prior to
this, levels stayed relatively stable
for thousands of years. Human
activities are adding more GHGs to
the atmosphere & boosting the
Greenhouse Effect that we learned
about in MODULE #1
• Temperature is increasing as
concentrations of CO2 (& other
GHGs) increase in Earth’s
atmosphere
U.S. Industrial
Revolution begins
Source: IPCC Report: Summary for Policy Makers,
Climate Change 2001: The Scientific Basis
… CO2 levels have now reached unprecedented highs,
and continue to rise steadily every year …
Graph courtesy of NASA. Data Source: Vostok ice core data/NOAA
How can we tell that the recent, rapid warming is caused by
human (anthropogenic) activity rather than natural cycles?
But when GHG emissions from human activities are included in the computer models, the
results match what scientists are seeing (temperature increasing)… so we are a key part of
the equation!
If scientists only consider Natural climate forcings (like solar & volcanic activity),
then computer models tell them Earth should’ve been cooling down over the past
30 years (gray line)… but that’s not what is happening in the real world (red line)
Why is this problem uniquely caused by us?
After all…
we humans live along with countless other species on planet Earth, and like all species
… change our environment to a greater or lesser degree.
… And change is inevitable.
…BUT the rate (and magnitude) of change we have caused since the industrial
revolution is much too great for the natural cycles to maintain a balance!
As the American Geophysical Union recently concluded: "It is scientifically inconceivable that
- after changing forests into cities, putting dust and soot into the atmosphere, putting millions
of acres of desert into irrigated agriculture, and putting greenhouse gases into the
atmosphere - humans have not altered the natural course of the climate system."
Let’s take a look at the major sources
of GHG emissions in Vermont…
Can you guess which 2 sources below are responsible
for nearly ¾ of Vermont’s Greenhouse Gas Emissions?
Industry?
Agriculture? Transportation?
Heating our homes
and businesses?
Electricity
generation / use?
Landfills?
Heating our homes
& businesses
Transportation
Vermont’s
Greenhouse
Gas
Emissions
27%
44%
11%
4% 6%
Electricity (1- 5%)
Landfills / Waste 3%
Industrial
processes
Agriculture
Industrial
fuel use
How does Vermont’s “emissions
profile” compare to the
entire United States?
GHG Emissions by
Source Category
(2000)
Transportation
26%
Residential /
Commercial
Fuel Use
9%
Agriculture
7%
Industrial Fuel
Use
14%
Electrictiy
32%
Landfills / Waste
4%
United States
Industrial
Processes
8%
Vermont
How do these 2 pie charts differ?
Can you think of reasons why
Vermont’s GHG emissions profile
looks different?
Please go on to MODULE #3 to learn about how GHG emissions are
changing things around the globe…