Center for Urban Forest Research
Urban Forests and Climate
Science
Jim Simpson
Center for Urban Forest Research
Pacific Southwest Research Station
U.S.D.A. Forest Service
Davis, CA
http://cufr.ucdavis.edu
Understanding the Urban Forest
Structure
Management
needs
Function
Value
Center for Urban Forest Research
Methods Flow Chart
Vegetation
Structure
Tree locations
Canopy Cover
Leaf Area
Biomass
Growth
Mortality
Diversity
Health
Site
Climate
Solar radiation
Air temperature
Wind speed
Precipitation
Building
Data
Energy
heating
cooling
Sequestration
CO2 released
& other
program costs
Structure
Stormwater
Runoff
Interception
Air Quality
Data
NOx, SOx
O3 , PM10
Aesthetics and
other Benefits
Dry
Deposition
Fire-safe
Landscapes
BVOCs
Isoprenes
Monoterpenes
Emission
Factors
Avoided
Emissions
CO2, NOx,
SOx, O3 , PM10
Energy & CO2
Center for Urban Forest Research
Air Quality
Improvement
Air Quality
Pavement
Durability
Other
Hydrology/Fire/other
Energy Conservation
How do trees influence energy use?
z
Trees Þ Climate
– Solar radiation (shade)
– Air temperature
– Wind speed
z
Climate Þ Energy use
– Cooling- electricity
– Heating- natural gas, etc.
z
Energy use Þ Air quality
– Criteria pollutants
– CO22
Center for Urban Forest Research
Effects on Peak Demand
Shade Tree Effects on Peak Electricity Demand
75,000
No trees
70,000
MW
65,000
177 M
60,000
50 M
55,000
101 M
112 M
50,000
154 M
45,000
2001
2003
2005
No Existing Trees
All Resid
Center for Urban Forest Research
2007
2009
Exist Trees
Res and Com/Ind
2011
2013
Resid E and W
All Sites
2015
Cost-Effectiveness of Shade
Tree Programs by Region
z
Best Case
Scenario
Present Value of Benefits per Tree Planted ($)
$0
North Coast
z
Heating Costs
and Cooling
Savings
Central Coast
South Coast
South Valleys
Inland Empire
North Ctr Valley
Mid Ctr Valley
z
25% Mortality
South Ctr Valley
High Desert
Low Desert
z
5% Discount
Rate
Center for Urban Forest Research
Mountains
$50
$100
$150
$200
Air Quality and CO2
z
Criteria Pollutants
– Uptake (dry deposition)
– Avoided Emissions at
Power Plants
z
Carbon Dioxide
– Sequestered
– Avoided
– Released
z
z
BVOC Emissions
Parking Lots
Center for Urban Forest Research
Desert Southwest, Phoenix
54
57
18
55
54
60
120
58
89
114
86
96
70
52
35
56
62
84
103
32
14
25
13
37
Net savings
(shade+climate)
5
Net loss
Units: kg CO 2/tree
California Coast
Pacific NorthWest, Seattle
22
43
22
43
21
22
42
41
13
14
13
18
34
15
22
17
37
29
15
22
22
44
49
25
38
10
43
47
Medium Deciduous
31
Net savings
(shade only)
-6
4
43
49
52
6
North Central, Detroit
E
S
69
52
45
34
8
61
W
19
post-1980 vintage
52
58
57
24
161
120
83
67
18
26
59
131
N
18
74
166
153
19
56
82
Regional Guidelines
Southeast, Atlanta
17
9
7
12
1914
8
10
14
-16
-30
-10
4
-4
14
5
-22 -16
2
5
-0
14
15
14
22
-5
-2
14
-14
-4
-20
-2
3
-6
Ecosmart
z
z
z
WaterWise –
minimize urban
runoff, water
conservation
EnergyWise –
energy
conservation
FireWise –
reduce chance
for structural
ignition
Center for Urban Forest Research
Landscape evaluation and design tool
STRATUM
Street Tree Resource Analysis Tool for Urban Forest Managers
Conduct sample inventory
Calculate structural
attributes
City zonation
Categorize estimated tree numbers by species
and DBH class
Tree numbers
Establishment of uniform sampling units
Species composition
Determine number of trees sampled per
zone segment
Relative age
Determine inventory protocols
Stocking level
Data collection
Diversity
Match species representing over 1% of
population with those from regional Community
Tree Guide
Group remaining trees into “other” categories
by tree types
Apply resource units to each tree in each zone
segment
Canopy cover
Assess costs
Condition
Planting
Internal
Estimate magnitude of benefits
Pruning
Conflicts
Tree & stump
removal
Pruning needs
Establish prices
Pest & disease
control
Electricity & natural Gas
Calculate net benefits &
benefit-cost ratio
Establishment &
irrigation
Calculate total
costs
Administration
Carbon dioxide
Calculate total
benefits
Stormwater runoff reductions
Inspection/service
requests
Property value
Litter clean up
External
Infrastructure
damage
Determine management needs
Diversity
Litigation &
settlements
Center for Urban Forest Research
Air quality improvement
Canopy cover
Planting &
maintenance
Collaborations
z STRATUM
z The
- Private sector
role of urban forestry programs in
carbon credit markets - Colorado State
Center for Urban Forest Research
Research Needed
z
Optimizing tree placement
– management goals
– multiple benefits and costs - optimum mix
z
Improved management tools
– Individual, landscape professional, planner, policy
makers
z
Expand focus from local/regional to global
scale?
– Local
– regional
– global
– Landscape – urban heat island – global warming
Center for Urban Forest Research
Research Needs (cont)
z Improved
estimates/models of sparse
canopies effects on climate and air
quality
z Deposition models for sparse
canopies/urban species
z BVOC base emission rates models
Center for Urban Forest Research
Questions?
http://cufr.ucdavis.edu
Center for Urban Forest Research
The End
Web-site: http://cufr.ucdavis.edu
Center for Urban Forest Research
EnergyWise
z
Optimize energy
savings via tree
location and
selection
z
Output: Heating
and cooling loads
and costs
– Shade effects
– Climate effects
z air temperature
z wind speed
Center for Urban Forest Research
Parking Lots
Trees and VOC Emissions
z
z
z
z
Lots 3 degrees cooler
Cabin 20-25 degrees
cooler
Gas temp 2-4 degrees
cooler
1 ton/day VOC reduction
with 50% shade
Center for Urban Forest Research
Hydrology
Reducing Runoff and Conserving Water
z
Measuring and
modeling rainfall
interception by trees
z
Scaling up from a
parcel to the
watershed
Center for Urban Forest Research
Aesthetic & Other Benefits
A = (L x T x C) / M
A = Average aesthetic benefit/tree ($)
L = Leaf area increase (m2/yr)
T = Sales price increase by large tree ($)
C = Tree location depreciation (%)
M = Large tree leaf area (m2)
Median home sales prices ($)
Center for Urban Forest Research
Modesto Santa Monica
26.11
64.82
8.9
5.1
900
3,969
78
84
250
250
102,000
450,000
Center Products
z Website
z Newsletter
z Fact
Sheets
z Summaries
z Tree Guides
z Publications
z Training
Center for Urban Forest Research
Regional Tree Guides
•
•
•
•
•
•
•
•
Project benefits & costs for 40years after planting
Yard and street/park trees
San Joaquin Valley
Coastal Southern California
Inland Empire, So. California
Western Washington & Oregon
Northern Mountain & Prairie
Bay Area (In Progress)
Center for Urban Forest Research
Tree Shade and Pavement Durability
Tree shade on streets:
z
z
z
Reduces thermal
loading: shoving,
rutting, aging
Reduces
repaving
frequency
Reduces
pavement
management
costs
Center for Urban Forest Research