Climate and Fire
Regimes
• Lake sediment cores
• Tree-rings
• Contemporary Records
Environmental Influences on
Fire Regimes
• Climate
• Substrate
• Topography
Charcoal Evidence of Fires
---1000s of Years
Cathy Whitlock
Univ. Oregon
Carl Skinner
PSW Redding
Sensitivity of Klamath Forests
to Long-term Changes in
Climate and Fire Regimes
•Pollen
•Charcoal
•Fire Scars
Bluff Lake – Mohr et al. 2000
Things
are often
not as
they at
first
appear.
Charcoal Influx & Fire Events
Mohr et al. 2000
- Climate • Fire
Frequency –
Temperature
• Fire Extent -Moisture
Tree-ring Evidence of Fires
----100s of Years
Alan Taylor
Penn. St. Univ.
Carl Skinner
PSW Redding
- Substrate • Site Productivity
• Ultramafics
• Fuel Breaks
-Topography• Topographic position
• Ridge tops
• Aspect
• Riparian Areas
Fire
Exclusion
Effect
Fire Severity Patterns
Upper Slope
Greater %
High Severity
Mid Slope
Intermediate
Lower Slope
Greater %
Low Severity
Taylor & Skinner 1998
Fire Severity Distribution
Thompson Ridge
South & West
North & East
100%
75%
High
Moderate
Low
50%
25%
0%
r
r
r
le
le
er
e
e
e
d
d
w
w
d
d
pp
pp
i
i
o
o
U
U
L
L
M
M
Taylor & Skinner 1998
Fire Severity Distribution
Typical fire burning under variable, mostly less
than severe, conditions
100%
75%
High
Moderate
Low
50%
25%
0%
2
9
in
a
t
n
u
o
F
it
u
sc
i
B
02
Typical fast moving,
severe fire.
e
7
g
8
k
id
r
R
n
fo
y
o
a
ps
H
m
o
Th
USDA
USDA Forest
Forest Service
Service 2003
2003
Taylor
Taylor &
& Skinner
Skinner 1998
1998
Weatherspoon
Weatherspoon &
& Skinner
Skinner 1995
1995
Fire
Occurrence
Groups
Fires were
limited by
topographic
features
(ridgetops,
streams, aspect
changes, etc.)
Taylor & Skinner 2003
Fire Regimes of the Sierra San
Pedro Martir, Baja California
Scott Stephens
UC Berkeley
Carl Skinner
PSW Redding
Jack Burk
CSU Fullerton (retired)
Climate & Fire Season Severity
Carl Skinner
PSW Redding
Alan Taylor
Penn. St. Univ.
Andrew Carleton
Penn. St. Univ.
Scott Stephens
UC Berkeley
Climate & Fire Season Severity
Focus: Mediterranean
climate area (MCA) of
western North America
32% of national fire
suppression and fuels
management funds
Where does the change set up?
Why?
Climate & Fire Season Severity
Objectives
• Determine how the dominant modes of climatic
th
century fire
circulation are related to 20th
extent.
• Determine how multi-century records of fire
regimes, dominant circulation modes, and fire
danger indices vary within the MCA
• Identify the key variables associated with
circulation modes that can be used to predict
problematic fire seasons months to years in
advance.
Fire
Scar
Sites