Introduction to Carbon Footprinting

Comprehensive practice flashcards covering greenhouse gas theory, carbon footprinting definitions, calculation scopes, and methodology based on the lecture notes.

Which gases are included in the 'Kyoto Basket' of the seven most important Greenhouse Gases (GHHs)?

$CO_2$, $CH_4$, $N_2O$, $SF_6$, HFCs, PFCs, and $NF_3$.

What are the 6 stages of Carbon Footprinting?

1. Emissions source identification: direct and l indirect.

2. Boundary setting: System, geographical, financial temporal, …

3. Selection of emissions calculations methods

4. Data collection: Primary or secondary data

5. Capturing scope 1 and 2 emissions

6. Capturing scope 3 emissions

What was the estimated magnitude of the 2023 methane mega-leak in the Mangistau region of Kazakhstan?

It is estimated that $127,000$ tonnes of the gas escaped during a blowout that raged for over six months.

How much has atmospheric methane ($CH_4$) increased compared to its pre-industrial level as of January 2023?

At $1,930\,ppb$, it has increased by a factor of 2.68 above its $722\,ppb$ pre-industrial level.

What is the definition of radiative forcing?

The difference between insolation (sunlight) absorbed by Earth and energy radiated back to space.

What is the difference between positive and negative radiative forcing?

Positive radiative forcing occurs when Earth receives more incoming energy than it radiates (causing warming), while negative radiative forcing occurs when Earth loses more energy to space than it receives (producing cooling).

How did Wiedman and Minx (2008) define a carbon footprint?

A measure of the exclusive total amount of carbon dioxide ($CO_2$) emissions directly and indirectly caused by an activity or accumulated over the life stages of a product.

How did Wright et al (2011) define a carbon footprint differently than Wiedman and Minx?

Wright et al (2011) defined it as a measure of the total amount of $CO_2$ and $CH_4$ emissions, calculated as $CO_2$ equivalents ($CO_2e$) using the relevant 100-year global warming potential ($GWP100$).

What is Scope 1 emission according to the Greenhouse Gas Protocol?

Emissions that occur as a direct result of, or within, the organizational or geographical boundaries (e.g., fuel combusted in company-owned vehicles or machinery).

What is Scope 2 emission according to the Greenhouse Gas Protocol?

Emissions from energy generation (such as electricity, steam, heating, and cooling) that occur upstream but are purchased for own consumption.

What is Scope 3 emission according to the Greenhouse Gas Protocol?

Indirect emissions that occur as a consequence of activities (like supply chain or product use) but occur outside the organizational or geographic boundaries.

What are the characteristics of the Process Analysis (PA) approach to carbon footprinting?

It is a bottom-up approach suited for environmental assessment of products; it offers high accuracy and transparency but requires significant time and resources.

What is Environmentally Extended Input-output analysis (EEIOA)?

A top-down approach that uses national economic and environmental data to estimate emissions of an industry sector; it is quick and inexpensive but less accurate than process analysis.

What is the standard formula for calculating carbon emissions ($E$)?

$E = AD \times EF$, where $AD$ is activity data and $EF$ is the emission factor.

What characterizes Tier 1 versus Tier 3 emission calculation methods?

Tier 1 uses non-specific data and IPCC default factors (high uncertainty), while Tier 3 uses technology-specific data, metered energy use, or direct monitoring (low uncertainty).

What is the 100-year Global Warming Potential ($GWP100$) of Methane ($CH4$ )?

27.9 or 28-36

What is the 100-year Global Warming Potential ($GWP100$) of ($N_2 O$)

310

What is the 100-year Global Warming Potential ($$of PFCs?

6500-9200

What is the 100-year Global Warming Potential ($GWP100$) of HFCs?

140-11700

What is the 100-year Global Warming Potential ($GWP100$) of Nitrogen trifluoride ($NF_3$)?

$17,200$.

What is the 100-year Global Warming Potential ($GWP100$) of Sulfur hexafluoride ($SF_6$)?

$22,800$.

What constitutes a 'Carbon Sink' or store?

A natural or artificial reservoir that stores Greenhouse Gases ($GHGs$) for an indefinite period, categorized into Soil organic carbon, Biomass, and Man-made products.

According to the Cardiff case study, which waste management activities provided the greatest GHG benefits?

Preparation for reuse, reprocessing (recycling), and Anaerobic Digestion ($AD$).

Why is biogenic carbon from landfills or biomass burning often considered 'carbon neutral'?

Because the $CO_2$ released during decomposition or burning was originally removed from the atmosphere via photosynthesis.