From Butterflies to Bristlecones:
Microclimatic and Topoclimatic Range
Adjustments as a Foundation for
Conservation in a Changing Macroclimate
Stuart B. Weiss MtnClim 2010
Andrews Exp. Forest
June 9, 2010

The Climate Near the Ground:
Spatial Hierarchy

Macro climate: 1000 - 20 km
Global Circulation, Synoptic Meteorology
Meso climate: 20 – 0.5 km
Coastal-Inland Carneros - St. Helena
Topo climate: 0.5 km - 10 m solar radiation relative elevation
N-S slopes, cold-air pooling, frost pockets
Micro climate: 100 m – 1 cm vegetation canopies
Organ ism: physiology, behavior

N 30
Flat
S 30

30
25
20
15
10
5
0
Clear-sky insolation is determined by latitude, day of year, aspect, slope, and horizon shading.
S30
S20
S10
FLAT
N10
N20
N30

60
50
40
30
20
10
0 b Nov 11 1992
S 30° S 22° S 12° FLAT N 12° N 22° N 30°
60
50
40
30
20
10
0 c Dec 16
1992
S 30° S 22° S 12° FLAT N 12° N 22° N 30°
60
50
40
30
20
10
0 d Jan 25 1993
60
50
40
30
20
10
0 e Apr 10 1995
S 30° S 22° S 12° FLAT N 12° N 22° N 30° S 30° S 22° S 12° FLAT N 12° N 22° N 30°
Noon surface T vary by 30+ C along N-S slope gradient, measured with IR thermometer, very different than air temperature. Linear function of insolation.

Black, Basking Caterpillars

Start pupation
Larvae grow faster on warmer slopes, up to a
5 week difference in emergence as an adult butterfly
Weiss et al. 1988 Ecology Vol. 69:1486-1496

~21 days from egg laying to diapause

Plant phenology follows topoclimatic gradients
S-slope N-slope g gy
N30°
N22°
N12°
FLAT
S12°
S22°
1990
17.1°C
20-Mar 3-Apr 17-Apr 1-May 15-May 29-May 12-Jun
N30°
N22°
N12°
FLAT
S12°
S22°
1991
14.3°C
20-Mar 3-Apr 17-Apr 1-May 15-May 29-May 12-Jun
N30°
N22°
N12°
FLAT
S12°
S22°
1992
17.6°C
20-Mar 3-Apr 17-Apr 1-May 15-May 29-May 12-Jun
N30°
N22°
N12°
FLAT
S12°
S22°
1993
15.7°C
20-Mar 3-Apr 17-Apr 1-May 15-May 29-May 12-Jun
N30°
N22°
N12°
FLAT
S12°
S22°
1994
15.4°C
20-Mar 3-Apr 17-Apr 1-May 15-May 29-May 12-Jun

Stratified sampling across insolation gradients
Tracks both numbers and spatial distribution
10 person-minute timed searches
Cover hundreds of hectares

1000000
100000
10000
100%
75%
50%
25%
0%
KC Reserve
VW
W
M
C
VC

Negative correlation with growing season (Oct-May) C
0.5
0.0
-0.5
-1.0
12.0
12.5
13.0
13.5
14.0
14.5
15.0
15.5
Oct-May Temp r 2 adj
= 0.35, P = 0.002

Mar-Apr C (-)
0.5
0.0
-0.5
-1.0
12 13 14 15 16
Mar-AprC Leverage, P<.0001
Oct-Nov Precip (+)
17
0.5
0.0
-0.5
-1.0
.0
2.5
5.0
7.5
10.0
12.5
15.0
Oct+Nov Rain Leverage, P=0.0168
Apr Precip (-)
0.5
0.0
-0.5
-1.0
-2.5
.0
2.5
5.0
7.5
10.0
12.5
Apr Rain Leverage, P=0.0005
r 2 adj
= 0.64
Beginning and end of growing season key!

28-May
21-May
14-May
7-May
30-Apr
23-Apr
16-Apr
9-Apr
2-Apr
26-Mar
19-Mar
85 86 87 88 89 90 91 92 93 94 95 96 97 98 99
Phenological Window:
Difference between peak emergence (square) and
Plantago senescence on
Flat (circle)
1
0.5
0
-0.5
-1
5 10 15 20 25
Phenological Window (Flat)
30 35
Timing may not be everything, but it is 63% of everything here.

Population increases = shift toward warmer slopes;
Population decrease = shift toward cooler slopes
Warmer growing season = shift toward cooler slopes
World largest
Thermometer?
1.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-1.0
-0.5
Log Rt
.0
r 2 adj
= 0.38,
P = 0.001
.5
1.5
1.0
0.5
0.0
-0.5
-1.0
-1.5
-2.0
-2.5
-1.5
-1.0
-0.5
.0
.5
1.0
1.5
2.0
2.5
Mean Temp Anomaly r 2 adj
= 0.39,
P = 0.001




Population dynamics driven by phenology – timing of development of larvae and foodplants (very common among animals)
Weather at beginning and end of growing season is most important
Topoclimatic diversity: range of insolation = range of temperatures = range of phenology = resilience


Opposing sides of a row of trees

Cluster here until strong NW winds

Cluster here until strong SW winds

Shift of Aspect: not enough heat

Pinus longaeva
Granite
Clastic
Limestone
Dolomite
White Mtn. Pk.

•35 iButton Thermochrons +/- 1 C (~$20 each)
•Affixed inside 6” lengths of white PVC tubes
•Placed on ground beneath sagebrush
•PVC openings facing north-south
•Recorded hourly temp. Jul. 23-Oct. 6, 2006

1 km

r = 0.0024

R 2 adj
= 0.92,
RMSE = 0.61 C
Extrapolate across the landscape

Downslope Migration: too much cold
Millar, Westfall, Delany, 2007

Local model embedded in an elevation lapse rate model (6 C = 1000m)
Embed in lapse rate from PRISM 800m norms

Mesoclimate: PRISM 800 m
1971-2000 averages

Daly et al. 2007 J. Appl. Met. Clim. 46:1565-1586





Downscale weather and climate to where organisms live
Macro-meso-topo-micro-climate
Local spatial climatic variation = resiliency
Maximum and minimum temperatures do not spatially coincide = fine-scale climatic complexity