Transcript climate presentation v2-1bbbx

How Climate Change has Impacted the
Frequency and Severity of California Wildfires
Scott Robleski
CLIMATE IN CRISIS (NRES-104)
Professor Low
Introduction
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Greenhouse Gases
• California is warming since the 1950’s is due to increased
levels of greenhouse gases (GHG) in the atmosphere.
• These gases warm the Earth’s surface by trapping heat.
• These gases include carbon dioxide, methane, nitrous oxide,
halocarbons and ozone.
• In California, vehicle emissions, electrical power generation
and industry account for over 80% of GHG emissions.
• Warming of the climate has increased the frequency and
severity of wildfires in California.
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Monthly Climates
• Between the months of October and March, snow
accumulates in the Sierra Nevada mountain range in
California. During Spring, the 'run-off' from the snow
supplies much of California’s annual water supply.
• Spring run-off to the Sacramento River has decreased
by 9% over the last century.
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Effects of Monthly Climate Change
• Lower run-off volumes may mean:
 Warmer winters where there is more rain instead of
snow.
 Earlier Springtime warming.
 Drought and more severe drought.
• All of which have severe implications increasing the
threat of wildfire.
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Reasons Why Fires Have Increased
• With the amount of greenhouse gases going into the
atmosphere the planet has started to warm.
• With the warming of the planet, grass and other natural
materials have become drier and thus more flammable
or likely to catch fire.
• Drier materials make it easier for fires to spread and
harder for responders to contain or put out the fire.
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Historical Data
• The three largest California fire years since 1950 have
occurred in the past decade (2003, 2007 and 2008).
• Annual acre average burnt since 2000 is 598,000,
which is almost twice that for the period of 1950-2000
(254,000 acres).
• The number of fires and size of all of the largest fires
have increased.
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Study Data
• American Geophysical Union study (need to put year
study was done here - its mentioned in the NBC News
article Dad forwarded to you).
• Data included both public and private land starting in
1984, totaling more than 6,000 fires.
• Regional causes and treatment of fires.
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Conclusions
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