Influences of climate trends on
snowpack and wildfire in the
West
Philip Mote, Univ. of Washington
Alan F. Hamlet, Univ. of Washington
Ze’ev Gedalof, Univ. of Guelph
McKenzie, Gedalof, Peterson, and Mote, 2004: Climatic change, wildfire, and
conservation. Conservation Biology, 18, 890-902.
Mote, Hamlet, Clark, and Lettenmaier, 2005: Declining mountain snowpack
in western North America. BAMS, in press, to appear January 2005.
Payne et al., Clim Chg 2004
Ron Neilson, USFS/OSU
At almost every
USHCN station,
winters warmed
+ signs: warming
but not statistically
significant
Fire-Climate Regression
Log10(Area)(t)=aTT(t)+aPP(t)+(t)
June-July-August T & P
for each state
Statewide area burned (various sources)
1916-2002
0.60
MT
2000
1988
0.57
OR
2002
0.51
WY
1988
0.48
WA
0.42
AZ
2002
Snow-climate regression
SWE(t)=aTT(t)+aPP(t)+(t)
November-March T & P
for each snow course (Apr 1)
Data from NRCS, BC, CA
Correlations between
Nov-Mar climate and Apr
1 SWE
X-direction: precip
Y-direction: temp
Coldest locations
insensitive to temperature
Cascades very sensitive
aP<P>
April 1 SWE trends, 1950-2002
aT<T>
aP<P> + aT<T>
Trends in Simulated Average APR 1 SWE for the Cascades in WA and OR (1950-1995)
600
Effects of TMP and PCP -54%
SWE (mm)
500
400
1-Apr
300
Linear (1-Apr)
200
100
y = -3.3822x + 365.25
450
995
992
989
986
Effects of PCP -28%
450
400
350
350
300
300
250
1-Apr
Linear (1-Apr)
200
1-Apr
250
Linear (1-Apr)
200
150
150
y = -1.6073x + 319.11
995
992
989
986
980
983
977
974
968
962
959
956
953
950
995
992
989
986
983
980
977
974
968
971
962
965
0
959
0
956
50
953
50
971
y = -1.7927x + 337.32
100
965
100
950
SWE (mm)
983
500
Effects of TMP -26%
400
980
977
974
971
968
965
962
959
956
953
950
0
Conclusions
Warming has caused, and will cause,
substantial declines in western
snowpack and increases in area burned
Cascades, N. Calif most temp-sensitive for
snow, AZ, NM, MT, WY most tempsensitive for fire
ftp://ftp.atmos.washington.edu/philip/SNOWPAPER/