Skip to main content

Advertisement

Table 1 Likelihoods of staying below specific temperature targets for various emission concentration pathways

From: 1.5°C or 2°C: a conduit’s view from the science-policy interface at COP20 in Lima, Peru

CO 2 -eq Concentration in 2100 (CO 2 -eq) * Category label (conc. range) Subcategories Relative position of the RCPs * Change in CO 2 -eq emissions compared to 2010 (in %) * Likelihood of staying below a specific temperature level over the 21st century (relative to 1850–1900) *
2050 2100 1.5°C 2°C 3°C 4°C
<430 Only a limited number of individual model studies have explored levels below 430 ppm CO2-eq*
450 (430 to 480) Total range* RCP2.6 −72 to −41 −118 to −78 More unlikely than likely Likely Likely Likely
500 (480 to 530) No overshoot of 530 ppm CO2-eq   −57 to −42 −107 to −73 Unlikely * More likely than not
Overshoot of 530 ppm CO2-eq   −55 to −25 −114 to −90 About as likely as not
550 (530 to 580) No overshoot of 580 ppm CO2-eq   −47 to −19 −81 to −59 More unlikely than likely *
Overshoot of 580 ppm CO2-eq   −16 to 7 −183 to −86
580 to 650 Total range RCP4.5 −38 to 24 −134 to −50
(650 to 720) Total range −11 to 17 −54 to −21 Unlikely * More likely than not
(720 to 1,000)* Total range RCP6.0 18 to 54 −7 to 72 Unlikely * More unlikely than likely
>1,000* Total range RCP8.5 52 to 95 74 to 178 Unlikely * Unlikely More unlikely than likely
  1. Source: IPCC AR5 Synthesis Report, 2014 [3]. *Footnotes explained in the original.