Projections: IPCC vs Mark Bahner

Table 1. Tropospheric temperatures (deg C).

Year	IPCC Projections	Mark Bahner Projections
	50% Probability	50% Probability
1990	0.00	0.00
2000	0.16	0.08
2010	0.34	0.18
2020	0.55	0.27
2030	0.80	0.36
2040	1.10	0.46
2050	1.42	0.58
2060	1.75	0.70
2070	2.17	0.82
2080	2.45	0.94
2090	2.70	1.05
2100	3.06	1.20

Year	IPCC Projections	Mark Bahner Projections
	50% Probability	50% Probability
1990	354	354
2000	369	369
2010	385	385
2020	413	405
2030	438	425
2040	470	455
2050	515	477
2060	560	502
2070	610	527
2080	645	542
2090	685	552
2100	720	558

Year	IPCC Projections	Mark Bahner Projections
	50% Probability	50% Probability
1990	1698	1698
2000	1770	1760
2010	1864	1770
2020	1950	1780
2030	2060	1790
2040	2120	1800
2050	2200	1810
2060	2250	1820
2070	2300	1825
2080	2350	1830
2090	2400	1835
2100	2450	1840

Table 4.  Methane concentrations (ppb)

Year	IPCC Projections	Mark Bahner Projections
	50% Probability	50% Probability
1990	6.0	6.0
2000	6.9	6.7
2010	8.7	7.4
2020	10.3	8.6
2030	13.2	8.8
2040	14.9	8.7
2050	16.0	8.3
2060	16.0	7.8
2070	16.4	7.0
2080	16.4	6.0
2090	17.1	5.0
2100	16.4	4.0

Table 3.  CO2 emissions (Gt as carbon).

Table 2. CO2 concentrations (ppm).