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Carbon footprints for
climate change mitigation
By: Divya Pandey and Madhoolika
Agrawal*
Global
warming is real and human beings are expected to get burns sooner or later if
significant actions are not taken to control the rising temperatures
immediately. The increase in temperatures is due to the enhanced greenhouse
effect due to anthropogenic release of greenhouse gases (GHGs) into the
atmosphere. Of these, the Kyoto gases i.e. carbon dioxide (CO2),
methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs),
perfluorocarbons (PFCs) and sulphur hexafluoride (SF6) are the
biggest contributors. For this reason, relevant steps have been taken at local
to national levels worldwide in the forms of carbon and energy taxes; adoption
of alternative energy sources including wind, hydro, geothermal and nuclear
energy; promotion of terrestrial, oceanic and geologic carbon sequestration; and
generating funds for GHG mitigation projects through carbon market. It has
become one of the most popular topics in the public domain. Contributions to the
public concern towards the issue came from famous books like “The End of Nature
(Bill McKibben, Random House, 1989)”, The Two-Mile Time Machine (Richard Alley,
Princeton University Press, 2000), “The Revenge of Gaia (James Lovelock, Allen
Lane, 2006)”, “Six Degrees (Lynas, Fourth Estate, 2007)” and movies like “An
Inconvenient Truth”; activities of non government organizations and media
covering political negotiations regarding the issue. Besides these, a renowned
term which has played an important role in proliferating awareness regarding the
individual responsibilities to limit GHGs and hence global warming, particularly
in developed world is “carbon footprint” (CF). Originally as a part of
“ecological footprint”, CF was an estimate of biologically productive land and
sea area required to absorb as much carbon dioxide as was generated during the
lifetime of an individual, or an activity. In lieu its importance in greenhouse
gas accounting and representations, CF became independent and increasingly
popular although its native form entirely got modified. The definition of carbon
footprint is still not uniform among the studies, however there is an apparent
nexus that it refers to the amount of GHGs emitted into or removed from the
atmosphere in terms of carbon dioxide equivalents, over a specified time period
from a well defined set of activities for which the entity is responsible. For
this relatively new concept, calculation methodologies are still evolving but it
has proven assistive in taking mensuration of greenhouse gas emissions to
households in an easily conceivable manner. Its use therefore has increased
among the businesses besides encouraging personal carbon calculating facilities
commercially. This article presents a brief introduction of carbon footprint,
its calculation and significance. An attempt has been made to analyze how
commercial businesses have responded to this technique of emission
quantification and representation.
Carbon
footprint calculations
In order
to estimate the net contribution of any activity to global warming, all the
relevant GHG emissions or removals, whether direct or indirect have to be
identified and accounted. In other words, it involves the complete life cycle
assessment of the product or activity with respect to GHGs. To address
complexities in such analyses, guidelines have been formulated. Important
resources are GHG protocol of World Resource Institute and World business
council for sustainable Development, Guidelines to National GHG inventories 1996
and 2006 of IPCC and ISO
14064 (part 1 and 2). Besides these, methods have been developed by government
and non government organizations, as well as by those involved in carbon
footprinting business. UK DEFRA, USEPA, The Climate Registry, and Carbon Trust
are few to name.
There are
three basic steps in CF calculation:
-
Identification of all relevant phases through which the product, event or activity has passed and
with which GHG emissions are associated.
-
Estimation of GHGs emitted at each identified phase.
-
Calculation of net
GHGs released or removed, in terms of CO2-e (usually at 100 year time horizon).
Life
cycle analyses helps identifying the relevant stages of the product, while
emissions and removals are calculated through direct measurements or utilizing
emission factors and models. Practically, only direct emissions (technically
called Tier I) such as in transportation and fossil fuel burning in boilers, and
emissions embodied in energy (Tier II) are included in CF calculations. For
realistic estimates however, tier III i.e. emissions associated with use and
disposal of a product should also be considered. Due to complexity and because
neither these emissions are considered in carbon markets nor are mandatory under
GHG accounting guidelines, this phase is left out in most of the studies. But as
more and more carbon footprinting studies will calculate end use emissions,
sector specific emission factors can be developed to cover broader boundaries
with reduced chances of error.
Popularity of carbon footprint
There exists a long list of activities for which CF have been
calculated. Be it an individual, our daily activities, consumer products, big
events, organizations, cities and countries, utilities or natural systems; CF is
widely employed as a quantitative indicator of climate friendliness.
Hundreds
of individual and household carbon calculators have surged the internet, which
yield CFs within minutes based on few inputs. Scientific comparisons indicate
that these calculators yield variable results and hence it becomes difficult to
select the appropriate one. Similarly, online calculators can yield CF of food
and travelling, particularly the air travels. The business of carbon offsetting
i.e. supporting GHG emission reduction or sequestration facilities financially
has given a boost to such calculators. These calculators compel their customer
to offset footprints. However, few of them are verified to make sure that
emission reduction could not have occurred if not supported financially through
offset sale. Offsets are usually generated through afforestation programs in the
third world countries and supporting renewable energy options. Big events like
conferences and sports events too get their CF calculated and take necessary
actions to manage their CF. An example to quote is the forthcoming London
Olympics 2012, for which CF calculations are going on. The estimated CF will be
reduced as much as possible. FIFA world Cup 2006 was declared as carbon neutral
through purchasing offsets for its CF of 1.0 x 105 t CO2-e.
While the
World Bank, UNO and UNESCO declared that they will calculate and reduce their
CFs, educational institutions are not lagging behind. Carbon footprints of
University of British Colombia and University of Pennsylvania have been
estimated to be 8.2750 x 104 and 3.0 x 105 t CO2-e
respectively. These were calculated using the emission factors derived from
respective resources, and it was found that for such institutions, emissions
embodied in purchased electricity contribute the largest to CF. A scoping study
has already been conducted to carry out carbon footprinting of schools in UK.
For cities, states and countries, CF is being utilized to guide the areas of
emission reductions. City of Seattle (7.013 x 106 t CO2-e
in 2000), The City of Vancouver, Canada (4.1983 X 107 t CO2-e
2006), Hawaii (2.154 X 107 t CO2-e in 2005) are few
examples. UNDP estimated world’s per capita carbon footprint to be 4.5 t CO2-e
in 2004.
It included only CO2 emissions in CF calculation for nations and
found United Arab Emirates leaving the biggest footprint with 34.1 tonCO2
and smallest by India (1.2 t CO2). The results were found
inconsistent with another study carried out by Edgar and Peters (2009), who made
use of a database “Global Trade Analysis Project” and considered other GHGs
also. Highest
CF and hence lowest carbon consciousness was reported for
Luxembourg (33.8 t CO2-e). Over consumptive behaviour of developed
countries yields higher CF whereas developing countries are unable to afford
emission control measures and cleaner techniques and substitutes. Even then,
their CF has been found to be the lowest. Carbon footprint for Bangladesh,
Mozambique and Uganda is estimates as 1.1t CO2-e.
On the
entire arena of getting prepared for fighting global warming, commercial
businesses hold a unique position as the target points of the laws and
governments when it comes to emission reductions and environmental protection,
but are also equally prone to every change in society and public behavior. At
the same time, they have to reap economic benefits from all the expected or
induced changes. They have sensed that the future will definitely be carbon and
energy constrained and therefore have started conforming accordingly. In Carbon
Disclosure Project 2009, 475 corporate over the world participated to get their
footprints calculated with 83 % revealing their emissions upto tier II only.
However, total
tier 3 emissions of 5.8 x 109 t CO2-e outweighed the
combined emissions of tier I and II (0.6 and 3.6 x 109 t CO2-e,
respectively). It indicates that emissions
beyond tier II have the biggest share in CF except for few biggest known
emitters including thermal power plants and cement manufacturing industries.
Consumer
preferences have shifted towards the products with low carbon content. LEK
consulting (2007) carried out a survey which showed that 44% of the consumers
preferred to buy products providing information about its CF and 43% preferred
to the product with low CF immaterial of its higher price. Therefore, corporates
are in a race to count and cut their CF. News Corporation and internet service
provider Google announced to go carbon neutral whereas others including General
Motors, Oil giant British Petroleum and Virgin Group, declared to invest in
technologies that help reducing their GHG emissions. Regardless of the fact that
natural processes contributing to GHG emissions are beyond our control, CF of
devastation caused by hurricane Katrina on US coast and wildfires have also been
estimated.
Importance of carbon footprints
The word
‘CF’ itself gives an indication that it shows something about the quantity of
carbon or related species. Its obvious cognition makes it popular among the
public as an indicator of one’s contribution towards global warming. An aware
citizen of the world therefore appreciates all possible measures that tend to
reduce CF of humankind. This has resulted in fundamental changes in governance,
people behaviour and businesses. It is clearly visible in the form of carbon
taxes and tariffs, numerous researches going on to evaluate carbon sequestration
options and rapidly growing carbon market. An important and substantial
contribution of CF is that it has compelled businesses to look towards cutting
their GHG emissions, whether or not heavy taxes are imposed by the government.
It is due to the business motivation rather than environmental consciousness
that is generated as more and more consumers tend to shift towards conservative
lifestyle and buy more environment friendly goods and services. When an
organization reveals and takes actions to limit CF, its image is improved
besides adding to its adaptation to expected stricter emission norms and getting
benefits in form of incentives for limiting emissions.
Individual carbon footprinting facilities have generated huge money through sale
of carbon offsets resulting in rise of carbon offsetting business that imparts a
sense of carbon neutrality among its buyers. For this reason,
voluntary carbon market has grown dramatically since 1989.
Ambiguities to be addressed
A vital
point is that, CF has become immensely popular business tool and CO2-e
is now being looked as a commodity, although neither there is a standard method
to verify and compare the CF calculations, nor is to determine the efficacy of
carbon offsets. Variations in sources, rates and periods of
emissions/sequestration amongst different processes and products or events make
comparisons more problematic. There is a need of strict vigilance over the
carbon markets and assets exchanged there. Similarly coherence in CF
calculations is indispensible when it is related to money transactions. Standard
guidelines make tier III optional, which is the known biggest contributor to
total GHGs emitted. Methodologies to include these emissions are thus
essential. CF of consumer products as well as in other carbon calculating
facilities must clearly indicate the extent of emissions covered to avoid
misleading interpretations. An initiative has been taken in the form of carbon
labeling in some countries, but unless it too provides details of the life cycle
stages covered in an understandable manner, its motive will be astray.
Conclusions
Contribution of CF for making GHG accounting illustrious at large scale is
appreciable. It has compelled businesses to cut down their emissions even if not
required so legally through raised public awareness towards eco friendly
products. This reflects its strength if employed in a well regulated way.
Although general public tends to calculate and reduce its CF for aroused sense
of environmental consciousness, there is no control over carbon calculating and
offset sale facilities. The business of carbon offsets is growing uncontested.
This must be checked so as to generate money for actual reductions. As CF is
still evolving, more studies are required in order to account for emissions and
removals beyond tiers I and II for more representative estimates that will guide
in better GHG management and control measures. In addition to these, there is an
urgent need to disseminate information about how to interpret CF, among general
public, so that merely what is shown to them doesn’t misled them.
*Laboratory of Air Pollution
and Global Climate Change, Department of Botany,
Banaras Hindu University, Varanasi-221005, India. |
