Download Climate Change - San Francisco Recreation and Park

Environmental/Health Concern: Climate change and
heat island effects
Relevant Research
(list/identify articles,
studies, etc.)
1) Meil, J and L Bushi. undated. Estimating the required global warming offsets to achieve a carbon neutral
synthetic field turf system installation. Athena Institute. Results reviewed by Melissa Capria, Climate
Change Coordinator, SF Dept. of the Environment
2) Dickey, Phillip. 2007. Synthetic turf versus natural turf for playing fields. Report commissioned by SF
Dept. of the Environment.
3) McNitt, Andrew S. and Dianne Petrunak. “Evaluation of Playing Surface Characteristics of Various InFilled Systems.” Pennsylvania State University, Department of Crop and Soil Sciences. 2006.
4) Williams, C. Frank, and Gilbert E. Pulley. “Synthetic Surface Heat Studies”, Brigham Young University,
2002.
Main Findings?
1)FINDINGS - CLIMATE CHANGE: 55.6 tons CO2/10 year period emitted for synthetic turf, and more if it is
not recycled. Compared to -16.9 tons/10-years for natural turf. Evidence of heat island impacts from
synthetic turf.
2) RELIABILITY OF DATA:
Athena Institute Study - Thorough report and plausible model but CO2 impact of landfill disposal is not
considered (synthetic turf). Decomposition of grass clippings would add to the CO2 impact of natural turf;
this was not considered either.
Factors to consider in looking at climate impacts of artificial turf vs. grass scenarios:
1. Emissions associated with fuel used in mowing/maintenance equipment.
2. Water usage and associated energy used for pumping.
3. Loss of soil sequestration benefit in the artificial turf scenario.
4. Emissions associated with pesticides and fertilizer in the grass scenario.
5. Any emissions associated with disposal of waste in either scenario (presumably the grass clippings are
being composted which would address this in that scenario)
6. Vehicle emissions associated with increased use of the fields.
7. Energy used for lighting the fields at night if they were not lighted before.
8. On the adaptation to climate change impacts side - ability to absorb stormwater.
9. The urban heat island affect, although this is not such a significant issue for us in our current climate it may
important as things heat up.
3) FINDINGS - HEAT ISLANDS: Initial results showed that the surface temperature of the synthetic field
was, on average, 39 degrees higher than the natural turf and 8 degrees higher than asphalt. At its hottest
point, the synthetic turf was 86.5 degrees hotter than grass. The study also found that cooling the synthetic
turf with water had very little effect on its temperature. Similar results were found by researchers at Penn
State, who examined the surface temperatures of several different brands of synthetic turf. On FieldTurf, the
difference between surface and air temperatures was 37 degrees.
4) RELIABILITY OF DATA: Did not completely assess.
Is this concern
relevant to and/or
significant forSan
Francisco synthetic
playfields? (given
conditions, materials,
typical uses)
CLIMATE CHANGE - RELEVANT. San Francisco has committed itself to ambitious goals for reducing
climate change impacts. If the Athena Institute study is correct and broadly applicable synthetic turf, it
strongly suggests that, unless the greenhouse gas emissions can be offset, the use of synthetic turf should
be minimized and confined to the sites where its other benefits are maximized. It also highlights the need for
recyclable synthetic turf.
HEAT ISLANDS - RELEVANT. It seems clear that there the synthetic turf does absorb considerably more
heat; however, this may not be important in San Francisco's mild climate except during exceptionally hot
spells.
Next Questions? What No further information needed. We know that synthetic turf will have undesirable climate change and heat
island effects. These need to be balanced against the benefits, and suggest that criteria should be
do we still need to
developed for selecting suitable installation sites.
know/ understand?
A larger scale, life-cycle analysis comparing synthetic and natural turf impacts is desirable, but this is well
beyond the scope of this task force, and is not essential for the current decisions being made.