How Climate Change has Impacted the Frequency and Severity of California Wildfires Scott Robleski CLIMATE IN CRISIS (NRES-104) Professor Low

2 xxxxxxx Introduction

3 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. Greenhouse Gases

4 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. Monthly Climates

5 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. Effects of Monthly Climate Change

6 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. Reasons Why Fires Have Increased

7 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 (254,000 acres). The number of fires and size of all of the largest fires have increased. Historical Data

8 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.

9 Conclusions