Session A13
Paper 6230
Disclaimer — This paper partially fulfills a writing requirement for first year (freshman) engineering students at the
University of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is
based on publicly available information and may not be provide complete analyses of all relevant data. If this paper is used
for any purpose other than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering
students at the University Of Pittsburgh Swanson School Of Engineering, the user does so at his or her own risk.
THE ROLE OF GREEN ROOFS IN REDUCING ENVIRONMENTAL HAZARDS
Ashley Dacosta, asd63@pitt.edu, Mahboobin 4:00, Isaiah Spencer-Williams, ims17@pitt.edu, Mahboobin 4:00
Revised Proposal — This paper outlines the advantages
of utilizing green roofs urban communities with a heavy
concentration of grey infrastructure. Green roofs are
vegetative surfaces laid on top of roofs to provide shade and
remove heat from the air, along with a myriad of other
benefits. These benefits include the restoration of some of
nature’s natural processes, improvements to ecosystem
services, profound effects on the water cycle, moderation of
weather and climates, and carbon sequestration. The
benefits of green roofs provide possible solutions to the
excessive amounts of runoff pollutants that cause health
concerns, as well as aquatic life concerns, the concern of
CSO (greenhouse gases) emissions, and the urban heat
island effect.
As a constantly developing society, we are a huge factor
in the overall progression of these concerns. As we continue
to advance our technologies to make them more efficient, we
also contribute to the excessive amounts of pollutants in
existence. This then leads to our environmental facilities
having to pick up the slack and work twice or even three
times as hard to account for all the environmental concerns.
For example, authorities such as PWSA (Pittsburgh Water
and Sewage Authority) and ALCOSAN (Allegheny County
Sanitary Authority) struggle to clean and efficiently process
storm water runoff when the city of Pittsburgh receives
heavy amounts of rainfall. Furthermore, this leads agencies
such as the National Energy Technology Laboratory (NETL)
to employ the usage of carbon sequestration to filter out the
harmful carbon dioxide gases (CO2) that contribute to the
pollution in the air through costly plans such as their
Carbon Sequestration Program. Carbon sequestration is
defined as the assimilation and storage of atmospheric
carbon in vegetation, soils, woody products, and aquatic
environments. In other words, carbon sequestration is the
use of plants and water to absorb CO2 gases out of the
environment. Although this process proves to be a grand
solution to fixing problems posed by pollution, it takes
companies such as NETL years to make the technologies
commercially available. Currently, large scale projects are
being developed in which the CO2 gas that is captured from
the air will be pumped deep underground, away from the
purified, green air. On the other hand, the problem with
these projects is that it is costly to create the machines
efficient and safe enough to perform this process, especially
University of Pittsburgh Swanson School of Engineering 1
2016/01/29
in a heavy populated area. However, another method to
capture carbon is to incorporate carbon sequestration with
green roofs, using sedum and other plants to capture the
gases inside the plant itself, as well as in the biomass in the
soil.
Additionally, we plan to highlight the mitigation of the
urban heat island effect. According to the Environmental
Protection Agency (EPA), a heat island is defined as “built
up areas that are hotter than nearby rural areas. The annual
mean air temperature of a city with 1 million people or more
can be 1.8–5.4°F (1–3°C) warmer than its surroundings”
[1]. These heat islands can cause increases in peak energy
demand, air pollution and greenhouse gas emissions, heatrelated illness and mortality, and water quality. Overall, the
goal of this paper is to highlight the beneficial effects that
green roofs provide to our society and to demonstrate that
we, as a society, have the potential to improve the quality of
our environment.
REFERENCES
[1] EPA. (2015). "Heat Island Effect.". Environmental
Protection Agency. (Website). http://www.epa.gov/heatislands
ANNOTATED BIBLIOGRAPHY
T.L. Daniels. (2010). "Integrating Forest Carbon
Sequestration Into A Cap-And-Trade Program To Reduce
Net CO2 Emissions." Journal Of The American Planning
Association 76.4: p. 463-475. (Online Article).
http://search.ebscohost.com/login.aspx?direct=true&db=aph
&AN=53921306&site=ehost-live
This article, from the Journal of the American Planning
Association, details the usage of forests in the lowering of
net CO2 emissions. This article describes forestry
management practices, how they can be implemented into
green roofs, and the Regional Greenhouse Gas Initiative,
which is a program to reduce CO2 emissions from coal-fired
power plants. Information from this article will help us
identify and discuss an important element of green roof
implementation and its effects on CO2 emissions.
Ashley Dacosta
Isaiah Spencer-Williams
J.C. DeNardo, A.R. Jarrett, H.B. Manbeck, D.J. Beattie,
R.D. Berghage (2005). “Stormwater mitigation and surface
temperature reduction by green roofs.” Trans ASAE, 48 (4).
(Online Article).
http://web.a.ebscohost.com/ehost/command/detail?sid=9388
ae0c-0296-4760-be5965857da17792%40sessionmgr4002&vid=29&hid=4212
This article from the American Society of Agricultural
and Biological Engineers outlines and discusses an
evaluation of a certain type of green roof and analyzes the
mitigation effects provided by green roofs. This article also
analyzes the surface temperature reduction aspects of the
green roof based on the different types of layers that can be
used when constructing it. Information from this article will
aid us in discussing what actually goes into the making of a
green roof and how those components affect mitigation and
stormwater runoff capture rates.
this article will help us in defining a green roof and what
purpose it serves, while giving us limiting information on
cost variability.
General Service Administration (2011). “The Benefits and
Challenges of Green Roofs on Public and Commercial
Buildings.” A Report of the United States General Services
Administration. (Online PDF)
http://www.gsa.gov/portal/mediaId/158783/fileName/Th
e_Benefits_and_Challenges_of_Green_Roofs_on_Public_an
d_Commercial_Buildings.action
This report from the United States General Services
Administration goes into detail about the use of green roofs
in urban and suburban environments. This report also
outlines the benefits and drawbacks of two different types of
green roofs in use. Information from this report will aid us in
speaking about the beneficial aspects of green roofs, while
providing us with real figures and statistical information
about green roof usage.
R. Dolesh (2012). “Parks Are Green Infrastructure.” Parks &
Recreation. (Online Article).
http://web.a.ebscohost.com/ehost/detail/detail?vid=82&sid=
9388ae0c-0296-4760-be5965857da17792%40sessionmgr4002&hid=4212&bdata=JnN
pdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=76147552&db=ap
h
This article from Richard Dolesh of the National
Recreation & Park Association looks at the significance and
value of parks and public green spaces as components of
sustainable development in the U.S. It regards resiliency,
which measures the natural systems function over various
conditions and challenges, as the key concept in
understanding the green infrastructure's importance and
value. Information from this article will help us in defining
what resiliency is and how it plays a key role in the
development of the green roof.
Getter, K. L. (2009). “Extensive green roofs: Carbon
sequestration potential and species evaluations” (Online
Article).
http://search.proquest.com/docview/304931533?accounti
d=14709
This dissertation written by Kristin Getter outlines and
details a study of the intrinsic carbon storage properties of
green roofs. This also outlines the importance of plant
choice and substrate depth when implementing a green roof
in terms of the carbon removal properties. Information from
this dissertation will aid us in explaining the different effects
that different plants have on the energy saving and
mitigation properties of green roofs.
K. Merry, et al. (2015). "Estimating Urban Forest Carbon
Sequestration Potential In The Southern United States Using
Current Remote Sensing Imagery Sources." Geographia
Technica 10.2 : 78-89. (Online Article).
http://search.ebscohost.com/login.aspx?direct=true&db=aph
&AN=110646927&site=ehost-live
This article from the University of Georgia and the
United States Department of Agriculture (USDA) outlines
the potential for Urban forestry, or the use of green roofs,
and other green infrastructures based on carbon dioxide
levels in certain areas. With the use of remote sensing
imagery, the USDA and the University of Georgia were able
to determine the availability of plantable areas using land
cover classes from the program Landsat 8. Information from
this will allow us to make sound determinations on whether
the use of a green roof is appropriate in certain areas and
will aid us in discussing location as a limiting factor for the
implementation of green roofs.
EPA . (2015) "Heat Island Effect.". Environmental
Protection Agency. (Website).
http://www.epa.gov/heat-islands
This article from the Environmental Protection Agency
defines the term “heat island.” The article describes the
effects it has on the environment and society. Information
from this article will aid us in defining the urban heat island
effect, as well as to describe the effects green roofs have on
it.
EPA. (2015). "Using Green Roofs to Reduce Heat
Islands." Environmental Protection Agency. (Online
Article).
http://www.epa.gov/heat-islands/using-green-roofs-reduceheat-islands
This article from the Environmental Protection Agency
defines the term “green roof,” and outlines some statistical
data from its usage in the United States. This also describes
the beneficial effects of the green roof and gives some
insight into the cost of implementation. Information from
National Energy Technology Laboratory. (2011).
“Enhancing the success of Carbon Capture and Storage
Technologies”. Technology Program Plan. (Online PDF).
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Ashley Dacosta
Isaiah Spencer-Williams
https://www.netl.doe.gov/File%20Library/Research/Carbon
%20Seq/Reference%20Shelf/2011_Sequestration_Program_
Plan.pdf
This PDF from the National Energy Technology
Laboratory discusses a plan started in 1997 to remove the
excessive levels of carbon emissions from the air. This PDF
also provides statistical analyses of the plan and the affect
that it will have on the environment. Information from this
PDF will aid us in the discussion of why plans such as this
are not sufficient enough in comparison to the
implementation of green roofs.
Yanling, L., & Babcock, J. W. (2014). “Green roof
hydrologic performance and modeling: a review.” Water
Science & Technology, 69(4), 727-738 .(Online article)
http://web.b.ebscohost.com/ehost/command/detail?sid=e036
99b3-bf9f-40fa-ab0e387249236a7a%40sessionmgr120&vid=26&hid=124
This article from the academic journal, Water Science &
Technology, reviews technical literature on green roof
hydrology. It discusses the effectiveness of the green roof
and its substantial variability due to design characteristics
that make performance predictions difficult. It also covers
the major factors affecting green roof hydrology as
precipitation volume, precipitation dynamics, antecedent
conditions, growth medium, plant species, and roof slope.
Information from this article will allow us to accurately
discuss and analyze real data on the performance of green
roofs.
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