Geographic varia-on in weather suitability for mountain pine beetle a8acks 1
1
2
Polly C. Buo*e , Jeffrey A. Hicke , and Haiganoush K. Preisler 1 Department of Geography, University of Idaho; 2 USFS Pacific Southwest Research StaMon Ø  Calculate historical and future weather suitability for beetle aAacks 1500
2000
500
1000
1500
2000
500
1000
1500
20
15
10
0
5
April-Aug T
-5
20
0
0
15
20
15
20
Fall T
0
log-odds of tree mortality
-5
0
5
10
15
20
April-Aug T
-4
-2
15
April-Aug T
0
2000
100 200 300 400 500 600
0
Previous summer precip (mm)
4-year summer precip (mm)
-5
0
5
10
April-Aug T
100 200 300 400 500 600
0
Previous summer precip (mm)
100 200 300 400 500 600
Previous summer precip (mm)
0 10000
Frequency
Previous summer precip (mm) 60000
Frequency
6000
Frequency
4-year summer precip (mm)
15000
Frequency
10
-4
0
4-­‐year summer precip (mm) 0
500
1000
1500
2000
4-year summer precip (mm)
0
500
1000
1500
2000
4-year summer precip (mm)
0
500
1000
1500
0
2000
100 200 300 400 500 600
0
-3
15000
5000
0
1940
1960
1980
2000
2
1
0
0
-1
-2
2050
2100
2050
2100
2050
2100
2
0
-2
-4
-6
1950
2000
2
3
Northern Rockies Northern
Rockies
1
25000
0.5
0.0
-0.5
-1.0
-1.5
1920
2000
Sierra Nevada Sierra
Nevada
2000
Northern Rockies Northern Rockies
1900
1950
0
1980
Previous summer precip
-1
1960
Fall/Spring-summer T
4-year summer precip
-2
1940
Combined weather
Winter T min
-3
1920
Previous summer precip (mm)
-8
-2
200
-1
400
0
1
600
2
800
SSierra
ierra Nevada
Nevada 1900
Previous summer precip (mm)
100 200 300 400 500 600
Cascades Cascades
2000
Weather suitability index
1980
Weather suitability index
1960
Area with mortality (km2)
1940
Area with mortality (km2)
1920
0
-3
0 500
-2.0
1900
Weather suitability index
1500
2500
Previous summer precip
-1.0
0.0 0.5 1.0
CCascades
ascades Fall/Spring-summer T
4-year summer precip
100 200 300 400 500 600
1950 – 2099 GCM data Area with mortality (km2)
1900 – 2009 PRISM data Combined weather
Winter T min
0
Previous summer precip (mm)
4-year summer precip (mm)
0
0
0
0
3b. Results for weather suitability: Historical and future drivers vary among regions Weather suitability
red = mortality 5
Frequency
2
0
log-odds of tree mortality
0
Frequency
1
0
-1
-2
-3
0
15
-5
0
4-year summer precip (mm)
10
80000
1000
5
Fall T
Frequency
500
0
Fall T
Frequency
0
-5
10 15 20
0
5
10 15 20
5
10
5 CCascades
ascades -5 Sierra evada Northern
N-5. R0ockies Sierra N
Nevada
Rockies Fall T
-5
20
Frequency
0
Winter T min (C)
-4
log-odds of tree mortality
1
0
-1
-2
-3
-5
-4
log-odds of tree mortality
1
0
-1
-2
-3
-4
-5
log-odds of tree mortality
Sierra Nevada 20
20
15
10
5
0
-5
-5
0
15
0
-5
10
4
-10
4
2
Winter T min (C)
-15
5
Fall T
Phloem thickness -20
0
Fall T
0
0
-5
Frequency
0
2
-5
20
-2
-10
15
-4
-15
10
log-odds of tree mortality
-20
Winter T min (C)
2
0
0
5
4
-5
0
6000
-10
10
-5
0
2
-5
0
-10
Winter T min (C)
2
-15
5
0
-5
-15
40000
Frequency
10000
April-Aug T
-20
Cascades Sierra evada NNorthern
. Rockies Cascades
SierraN
Nevada
Rockies -20
April-Aug T
15
0
-2
-5
Frequency
-10
0
-15
WinterTT min
(C) (C) Winter min Tree drought stress 20
3
2
1
0
-1
-3
-20
Frequency
0
Frequency
-5
CCascades
ascades Sierra evada Northern
N. Rockies Sierra N
Nevada
Rockies -2
log-odds of tree mortality
3
2
1
0
-1
-3
-10
4000
-15
Winter T min (C)
0
-2
log-odds of tree mortality
3
2
1
0
-1
-2
-3
-20
Frequency
Northern Rockies AdapMve seasonality (1 year life cycle and mass emergence) Cascades
SierraN
Nevada
Rockies Cascades Sierra evada NNorthern
. Rockies Weather suitability
Ø  Explanatory processes represented by a suite of poten@al variables Ø  Select best variable for each process using AIC Beetle winter mortality Weather suitability
Here we used sta@s@cal modeling to compare the following across 3 geographic regions: • climate-­‐beetle rela@onships • historical and future weather suitability for beetle aAacks 2. Methods Ø  Es@mate the probability of tree mortality using a logis@c generalized addi@ve model 3a. Results for climate-­‐beetle rela,onships: Some exhibit geographic variability log-odds of tree mortality
1. Introduc,on Since 1997 mountain pine beetles have killed roughly 17% of the area of lodgepole pine in the western United States. Our previous work in whitebark pine and other studies in lodgepole pine suggest spa@al variability in the weather condi@ons that promote beetle aAacks. 1950
2000
4. Conclusions Ø  Climate-­‐beetle rela@onships, and historical and future weather suitability paAerns vary substan@ally across geographic regions Ø  Vulnerability assessments should consider geographic variability in sensi@vity 5. Acknowledgements: This work was funded by the USDA NIFA Forest Mortality, Economics, and Climate (FMEC) Project, the USGS Northwest Climate Science Center, and the USGS Western Mountain Ini@a@ve