Units, conversions

k : Abbreviation of kilo, corresponding to a factor $10^3=1\,000$
M : Abbreviation of mega, corresponding to a factor $10^6=1\,000\,000$
G : Abbreviation of giga, corresponding to a factor $10^9=1\,000\,000\,000$
T : Abbreviation of tera, corresponding to a factor $10^{12}=1\,000\,000\,000\,000$
P : Abbreviation of pert, corresponding to a factor $10^{15}=1\,000\,000\,000\,000\,000$
E : Abbreviation of exa, corresponding to a factor $10^{18}=1\,000\,000\,000\,000\,000\,000$

The energies related to oil combustion are only approximate

J : Joule (kJ = kilojoule, MJ = megajoule, GJ = gigajoule, EJ = exajoule)
Wh (watthour) : 3600 J or 3.6 kJ
kWh : kilowatthour = 3.6 MJ
MWh : mégawatthour = 3.6 GJ = 0.086 toe
Twh : terawatthour = 0.0036 EJ. We use the convenient conversion 1000 Twh = 3.6 EJ.
toe : ton of oil equivalent, around 11.63 MWh or 41.89 GJ.
Mtep : megaton of oil equivalent, around 11.63 TWh
Barrel of oil : 159 liters of oil (42 US galons…), whose combustion gives 1.59 MWh or 5.73 GJ.
1 liter of oil de pétrole, or 0.00086 tep, releases 10.0 kWh.
1 m³ of oil : 1000 liters of oil, equivalent to 0.86 teoe, yielding 10.0 MWh.

GtCO2 : 1 billion tons de CO₂
GtC : 1 billion de tons of carbon (corresponding to 3.667 GtCO2 after combustion)
ppm : parts per million, or 0.0001%. A concentration of 1ppm for a given gas, means that one molecule on 1 million molecules is of that specific gas type.
ppb : parts per pillion, or 0.0000001%. A concentration of 1ppm for a given gas, means that one molecule on 1 billion molecules is of that specific gas type.