Carbon Emission Numbers for Consumers to Know but Centered on Aaron and San Francisco

44 billion t
max in 2020 if we are to avoid catastrophe
In order to limit the rise in average global temperatures to 2 degrees Celsius by 2100, the UN-affiliated Emissions Gap Report of 2013 "recommends that emissions should reach a maximum of 44 gigatonnes of CO2 by 2020, falling to 40 gigatonnes by 2025 and further to 22 gigatonnes by 2050."1

40 billion t
max in 2025 if we are to avoid catastrophe

37 billion t
world total emissions in 20172

20 billion t
max in 2050 if we are to avoid catastrophe

20 t
annual average per American3
Includes 8.5 t due to government services when equally divided between all Americans. Another source says the the total is 16.4 t.4

7.56 t
flying SF to London business class nonstop round trip5
This uses a radiative forcing factor. Without radiative forcing, it's 4.00 t.

4.9 t
annual average per human
Assuming 7.5 billion humans in March 2018.6

4.41 t
annual gas consumption of my home
Assuming 0.0061 t per therm for PG&E,7 and assuming that our gas usage in Feb 2018 was 50% more than monthly average. EPA suggests national average is 0.0053 t per therm.8

4.37 t
driving SF to FB HQ round trip by every weekday for a year9
28 MPG, 28 miles x 2. One trip is 0.017 t.

2.61 t
flying SF to London economy class nonstop round trip5
This uses a radiative forcing factor. Without radiative forcing, it's 1.38 t.

1.75 t
driving SFO to JFK round trip9
28 MPG, 2939 miles x 2

1.35 t
annual electricity consumption of my home
Assuming 0.0197 t per MWh for PG&E,10 and assuming that our electricity usage in Feb 2018 was equal to the monthly average. EPA suggests national average is 0.0744 t per MWh.8

1.15 t
flying SFO to JFK economy class nonstop round trip5
This uses a radiative forcing factor. Without radiative forcing, it's 0.61 t.

0.52 t
eating 1 lb beef per week for a year
Assuming 0.022 t per kg beef.11 Average American beef consumption was 1.07 lb per week in 2016.12

0.23 t
driving SF to Caltech round trip9
28 MPG, 387 miles x 2

0.15 t
flying SFO to LAX economy class nonstop round trip5
This uses a radiative forcing factor. Without radiative forcing, it's 0.08 t.

0.12 t
driving SF to Yosemite Valley round trip9
28 MPG, 194 miles x 2

0.10 t
drinking 1/2 gallon cow milk per week for a year
Assuming 0.001 t per kg milk.13 Re-calculating with numbers from a different source, total is 0.12 t to 0.15 t per year.14 Assumes 1 gallon of milk weighs 8.6 pounds.

0.084 t
drinking 1/2 gallon soy milk per week for a year
Well, calculating with numbers from source 14, the total is 0.079 t to 0.089 t per year.

0.029 t
driving SF to San Jose round trip9
28 MPG, 48.5 x 2 miles

1https://ourworld.unu.edu/en/carbon-emissions-must-be-cut-significantly-by-2020-says-un-report
2https://news.nationalgeographic.com/2017/11/climate-change-carbon-emissions-rising-environment/
3https://www.sciencedaily.com/releases/2008/04/080428120658.htm
4https://calculator.carbonfootprint.com/calculator.aspx?tab=8
5https://calculator.carbonfootprint.com/calculator.aspx?tab=3
6https://www.census.gov/popclock/
7https://www.pge.com/includes/docs/pdfs/about/environment/calculator/assumptions.pdf
8https://www.epa.gov/energy/greenhouse-gases-equivalencies-calculator-calculations-and-references
9https://calculator.carbonfootprint.com/calculator.aspx?tab=4
10https://www.pge.com/en_US/about-pge/environment/what-we-are-doing/fighting-climate-change/fighting-climate-change.page
11https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2535638/
12https://www.usatoday.com/story/money/2017/07/03/americans-eat-more-beef-and-meat-trend-thats-expected-continue/435331001/
13https://www.sciencedirect.com/science/article/pii/S002203021731069X
14https://crueltyfreelife.wordpress.com/2013/06/14/sustainability-of-dairy-milk-vs-soy-milk/

Units are metric tons of CO2 equivalents
Compiled by Aaron Gabriel Feldman in April 2018