A Bayesian Network Modeling Approach to Forecasting the 21st Century Worldwide Status of Polar Bears - Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications - page 254

Table C2. (continued)

Node Mutual Information Node Title

Test 10: Sensitivity of Node L2—Vital Rates

l1 1.04302 adult female survival

l 1.04048 juvenile survival

F2 0.93484 factor a: habitat threats

k 0.92047 adult body condition

V1 0.64819 cub production per event

U 0.34420 reproduction

M 0.04217 ecoregion

N 0.01843 shelf distance change (km)

APPENDIX D: INPUT VAlUES USED IN ThE
BAyESIAN NETWORk POlAR BEAR POPUlATION
STRESSOR MODEl FOR EACh OF FOUR POlAR
BEAR ECOREGIONS

each of four polar bear ecoregions. Separate input values
were provided for each time period projected and for the en-
semble mean of general circulation model outputs as well as
for individual GCMs that projected the maximum and mini-
mum sea ice remaining in each time period.

Tables D1a and D1b present input data values used in the
Bayesian network polar bear population stressor model for

Table D1a. Input Data Values for Nodes B, C, N, S1, R3, R2, and F Used in the Bayesian Network Polar Bear Population Stressor Model
for Each of Four Polar Bear Ecoregions

Node and Variable Name b

B:
Foraging
habitat
Quantity
Change
(%)

C:
Foraging
habitat
Absence
Change

N:
Shelf
Distance
Change c
(km)

S1:
Foraging
habitat
Character

R3:
Alternative
Prey
Availability

R2:
Relative
Ringed Seal
Availability

F:
Alternative
Regions
Available

Sea Ice Data
Source Time Period a

Seasonal Ice Ecoregion

year -10 Satellite data 17.14 -0.7 NA more_optimal decrease increase yes

year 0 Satellite data 0.00 0.0 NA same_as_now same_as_now same_as_now yes

year 25 GCM minimum -4.17 0.1 NA same_as_now same_as_now decrease yes

year 50 GCM minimum -10.36 1.0 NA same_as_now decrease decrease yes

year 75 GCM minimum -31.89 2.5 NA less_optimal decrease decrease yes

year 95 GCM minimum -32.11 2.7 NA less_optimal decrease decrease yes

year 25 Ensemble mean -4.65 0.3 NA same_as_now same_as_now decrease yes

year 50 Ensemble mean -14.62 1.0 NA same_as_now decrease decrease yes

year 75 Ensemble mean -25.75 1.6 NA less_optimal decrease decrease yes

year 95 Ensemble mean -27.83 1.8 NA less_optimal decrease decrease yes

year 25 GCM maximum -0.05 0.1 NA same_as_now same_as_now decrease yes

year 50 GCM maximum -6.71 0.7 NA same_as_now decrease decrease yes

year 75 GCM maximum -21.16 1.3 NA same_as_now decrease decrease yes

year 95 GCM maximum -21.69 1.7 NA same_as_now decrease decrease yes

Archipelago Ecoregion

year -10 Satellite data 3.21 -0.5 NA less_optimal same_as_now decrease no

year 0 Satellite data 0.00 0.0 NA same_as_now same_as_now same_as_now no

year 25 GCM minimum -6.16 0.6 NA more_optimal same_as_now increase no

year 50 GCM minimum -13.79 1.1 NA more_optimal increase increase no

year 75 GCM minimum -20.71 2.0 NA same_as_now decrease decrease no