Will people or policies save the planet?
Societal changes are needed to avert the climate crisis but the knowledge of individuals is powerful.
We use measurements to determine our starting point, and to assess progress. According to Our World in Data (2017):
- Per capita CO2 emissions: 4.73 tonnes.
- Total CO2: 36.44 billion tonnes of CO2.
- Total CO2e: 49.36 billion tonnes of CO2e (2016).
- World population: 7.55 billion *.
The global carbon budget, published annually, provides an account of the balance between carbon sources - emissions - and sinks. The movement of carbon atoms betweens sinks and sources is called the carbon cycle, and it is perturbations in this cycle which cause global warming. Since 1950 around natural sinks, though at variable rates. Due to carbon fertilisation, and other factors, including increased use of nitrogen, natural sinks have been taking up more carbon dioxide, though this upward trend may not continue.
Negative emissions refer to greenhouse gases, primarily carbon dioxide, removed from the atmosphere, either though biogenic means (including planting trees, and restoring mangrove forests and sea grasses), or by artificial methods such as direct air capture (DAC).
Carbon capture and storage, and carbon offsetting are used, at best, to keep emissions from an activity carbon neutral; they do not reduce carbon already in the atmosphere.
Unfortunately CO2 is not the only greenhouse gas; emissions from methane, nitrous oxide, and Fluorinated gases (F-gases) must also be taken into account. Total emissions are measured using carbon dioxide-equivalents.
The total figure for all greenhouse gas emissions is therefore higher, more than 50 billion tonnes of CO2e.
The climatologist, Michael E Mann, argues that whilst individual action is important, it must not distract from policy. In an article for Time, Lifestyle Changes Aren’t Enough to Save the Planet. Here’s What Could, he writes,
Carbon footprint of societies
Benefits of carbon footprints
- Provide a basic framework for how to think about climate change numbers.
- Show our dependency on fossil fuels.
- Can establish good practices and measurable outcomes e.g. the Ecological Footprint Standards (PDF)
Downsides of carbon footprints
- Individual profiles are primarily based on averages with minimal personal data.For a comparison compare one carbon footprint calculator for UK farmers which takes 30 mins to 2 hours to complete.
- Tracing back carbon emissions is hard; many calculations are derived from assumptions based on figures for large units, usually countries.
- The background or implicit value for the region where the user lives is not separated out, although an average for that region is often given.
- There is no oversight, and no formal process of review; this makes it hard for the public to know which calculators are accurate or reliable.
- Our good intentions can be undone by primary cognitive biases.
Individual carbon footprint calculators
- William Rees and Mathis Wackernagel use the term ecological footprint for the first time in an academic publication.
- BP launches the first carbon footprint calculator and spends millions promoting the concept.
- BP launches a second carbon calculator. It does not receive a favourable reception.
There are numerous carbon footprint calculators. I have listed a few that seem more or less accurate but I would recommend using three or four to obtain an average. Any value should be treated as a rough approximation. As emissions are tied to particular goods and services, we can expect greater accuracy and specificity.
- Global Footprint Network
- UN carbon footprint calculator
- Mossy Earth
- Carbon footprint
- Know Your Carbon footprint (BP)
- The Nature Conservancy (US only)
- Native (US only)
- US Environmental Protection Agency (US only)
- COTAP.org – Carbon Offsets To Alleviate Poverty (US only)
- World Wildlife Fund (UK only)
- giki zero (UK only)
- CarbonClick (NZ & AUS only)
Results from 5 calculators
I used 5 calculators to find my carbon footprint. +
|Global Footprint Network||2.6t CO2e||true||true|
|UN carbon footprint calculator||3.37t CO2e||true||true|
|Mossy Earth||6.54t CO2e||true||true|
|Carbon footprint||2.11t CO2e||false||true|
|Know Your Carbon footprint (BP)||6.35t CO2e||true||true|
Why are there such large discrepancies between footprints?
Calculators accept a variety of information, and differ as to external baseline data and assumptions; this does not necessarily make one better than another; all of these calculators are well researched, and independently valuable, but direct comparison between them is not possible. Discrepancies are a cautionary reminder that, when dealing with climate change figures, it is more constructive to think in terms of ranges than specific figures, and that the ranges themselves fluctuate. The value of our footprint is seductive, an effective means of engagement; how the number was derived is more valuable.
Calculators are necessarily constrained by the information we provide, but whilst certain inferences can be made from the data we do provide, they are agnostic as to some important factors that affect our behaviour and options; wealthier people have more choice as to where they live, and how they live. Nor do these calculators take into account our work which may have a footprint at odds with our private one. The reason for this is to avoid double counting emissions - if you make cars, the car owners are responsible for those emissions, not the manufacturer; but since these are personal emissions calculators, this limits their value.
And finally, they are snapshots, which don't take into account our history, or future plans. If we assume that carbon emissions must peak, and decline, in order to meet the goals set in Paris in 2015, the effect on individual lifetime carbon budgets is startling.
- Do not offer the option to share the results of footprints because they are free of important context, and are not comparable; but do share the calculator itself.
- Show workings and explain assumptions.
- Follow, or reference, Ecological Footprint Standards (PDF).
- Indicate the implicit, background carbon footprint.
- Include and explain carbon dioxide-equivalents.
Carbon footprints are sometimes used as a proxy for individual acts, which are then placed in opposition to political or social acts, limiting choice to one or the other, either/or.
One reason for this polarity is that fossil fuel companies have promoted the idea that emissions reduction is the responsibility of individuals, and one of the tools they have used is the carbon footprint; not only was BP the first to popularise the concept, they have released carbon footprint calculators twice, in 2006 and 2020, to coincide with campaigns defending or stating their green credentials.
Do individual acts detract from systemic changes that might be more productive?
Two recent studies provide evidential support that we keep a tally of our moral acts, and are quick to call in our debt; acceptance of one tax, even at the lower end of a range, lessens acceptance of further taxation. A paper in Nature that looked at how small changes might adversely affect willingness to accept larger ones, concluded,
The choice, however, is ours, we can save electricity and water, become a vegan and run for office. If we think we can combine personal and political action, then we should, and trust others to do the same.
What of the actions themselves, do they have intrinsic value? Does knowing the average emission of a transatlantic flight, or the carbon dioxide-equivalent per kilo of beef mean anything?
A decision which may involve inconvenience, loss of income, or the forfeit of a pleasure, is sustained more readily when it has solid foundations, for then the reason behind, and the need for, the change, is clear, even if any ultimate benefit that accrues is indiscernible.
It is against the grain for most to forego gratification or gain, but it is hard to ignore that which is right to do, when that right has been established and understood. We may call this conscience, sense of duty, or moral imperative; and we may discover that acting in accordance with our beliefs and our understanding, is less disruptive, and more sustaining, than we imagined.
Carbon footprint calculators have value as an introduction to the consequences of our choices, and as a starting point for examining our interdependency, lack of autonomy, and the limits pertaining to personal action.
Footprints would be improved by making the implicit cost of services explicit. This intrinsic, background value for a society is the floor below which individual action cannot take us, and which can only be breached by direct, participatory action that brings about policy change.
* There is a discrepancy hidden in these figures:
+ My profile
- No meat, cheese, eggs most days, no milk
- 40% fresh, 60% packaged (pasta, beans, coffee, oats, oat milk, wine)
- 80% local food (within 320k)
- Living in a city centre
- Country: Portugal
- One occupant in 66m2 flat in multi-storey concrete, steel and glass building
- Well-insulated building in maritime climate; low electricity use, no air conditioning
- Electricity & Gas 166kWh per month, 50% renewable
- Rubbish: relatively low, little waste, recycle
- Eat out once a week
- No car, or bike, etc. Rent rarely.
- 10 kilometres per week bus
- 10 kilometres per week train
- 4 hours flying per year