The concentrations of CO₂ and CH₄ considered here correspond to the year 2000 and differ slightly from those considered in Chapter 6 which used the values corresponding to the year 1998 (as appropriate for the time frame when Chapter 6 began its preparation). The resulting difference in the computed present day forcings is about 3% in the case of CO₂ and about 2% in the case of CH₄. For N₂O, the difference in the computed forcings is negligible. In the case of tropospheric ozone, the forcing for the year 2000 given here and that in Chapter 6 are the results of slightly different scenarios employed which leads to about a 9% difference in the forcings. For the halogen containing compounds and aerosols, the difference in forcings between here and Chapter 6, if any, are inconsequential (note: numbers are rounded off in Chapter 6).

ISAM model (reference) - CO2 radiative forcing (Wm-2)
Year	A1B	A1T	A1FI	A2	B1	B2	A1p	A2p	B1p	B2p	IS92a	IS92a/SAR
2000	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.56
2010	1.82	1.80	1.80	1.81	1.78	1.78	1.85	1.82	1.78	1.81	1.81	1.85
2020	2.21	2.10	2.17	2.17	2.10	2.05	2.27	2.19	2.07	2.13	2.14	2.18
2030	2.62	2.46	2.64	2.59	2.42	2.32	2.71	2.61	2.32	2.43	2.50	2.53
2040	3.04	2.82	3.18	3.03	2.73	2.61	3.13	3.05	2.58	2.72	2.87	2.88
2050	3.47	3.15	3.81	3.47	3.01	2.90	3.53	3.50	2.83	2.99	3.23	3.24
2060	3.86	3.43	4.44	3.93	3.24	3.18	3.91	3.96	3.11	3.27	3.58	3.59
2070	4.21	3.65	5.06	4.42	3.40	3.46	4.25	4.44	3.37	3.54	3.95	3.93
2080	4.54	3.81	5.65	4.93	3.52	3.74	4.56	4.93	3.59	3.81	4.32	4.29
2090	4.82	3.91	6.20	5.46	3.60	4.02	4.82	5.46	3.78	4.09	4.71	4.66
2100	5.07	3.95	6.69	6.02	3.64	4.30	5.05	6.02	3.92	4.38	5.11	5.05

ISAM model (low) - CO2 radiative forcing (Wm-2)
Year	A1B	A1T	A1FI	A2	B1	B2	A1p	A2p	B1p	B2p	IS92a
2000	1.50	1.50	1.50	1.50	1.50	1.50	1.50	1.50	1.50	1.50	1.50
2010	1.71	1.69	1.69	1.70	1.67	1.67	1.74	1.71	1.67	1.70	1.70
2020	2.01	1.92	1.99	1.97	1.92	1.87	2.07	2.00	1.88	1.95	1.96
2030	2.36	2.19	2.37	2.32	2.16	2.08	2.43	2.35	2.08	2.17	2.25
2040	2.71	2.49	2.84	2.69	2.41	2.30	2.78	2.71	2.27	2.40	2.53
2050	3.06	2.76	3.40	3.06	2.64	2.53	3.12	3.09	2.48	2.62	2.83
2060	3.39	2.99	3.97	3.47	2.81	2.76	3.43	3.49	2.69	2.84	3.13
2070	3.69	3.15	4.52	3.90	2.92	2.99	3.72	3.91	2.91	3.05	3.44
2080	3.95	3.26	5.05	4.34	2.99	3.21	3.96	4.35	3.09	3.28	3.76
2090	4.18	3.31	5.54	4.83	3.03	3.45	4.18	4.83	3.21	3.51	4.10
2100	4.38	3.31	5.99	5.35	3.03	3.69	4.35	5.35	3.32	3.76	4.46

ISAM model (high) - CO2 radiative forcing (Wm-2)
Year	A1B	A1T	A1FI	A2	B1	B2	A1p	A2p	B1p	B2p	IS92a
2000	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51	1.51
2010	1.91	1.87	1.87	1.88	1.87	1.85	1.92	1.89	1.85	1.89	1.89
2020	2.35	2.23	2.30	2.30	2.23	2.17	2.40	2.32	2.18	2.26	2.28
2030	2.81	2.64	2.82	2.76	2.60	2.49	2.89	2.80	2.50	2.61	2.69
2040	3.28	3.04	3.42	3.26	2.96	2.83	3.36	3.29	2.80	2.94	3.12
2050	3.75	3.42	4.09	3.76	3.29	3.16	3.82	3.78	3.10	3.27	3.54
2060	4.20	3.75	4.77	4.27	3.56	3.49	4.25	4.29	3.42	3.58	3.96
2070	4.59	4.03	5.43	4.79	3.78	3.81	4.63	4.80	3.73	3.91	4.39
2080	4.96	4.23	6.06	5.34	3.94	4.13	4.99	5.35	3.99	4.22	4.80
2090	5.30	4.39	6.64	5.90	4.06	4.46	5.30	5.90	4.21	4.54	5.23
2100	5.59	4.48	7.17	6.49	4.14	4.79	5.58	6.49	4.41	4.87	5.68

Bern-CC model (reference) - CO2 radiative forcing (Wm-2)
Year	A1B	A1T	A1FI	A2	B1	B2	A1p	A2p	B1p	B2p	IS92a	IS92a/SAR
2000	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.53
2010	1.78	1.76	1.76	1.76	1.76	1.74	1.81	1.78	1.74	1.77	1.77	1.82
2020	2.18	2.08	2.14	2.13	2.08	2.03	2.22	2.16	2.04	2.10	2.12	2.16
2030	2.54	2.40	2.56	2.50	2.36	2.27	2.62	2.54	2.27	2.37	2.44	2.50
2040	2.96	2.76	3.09	2.93	2.66	2.55	3.03	2.97	2.52	2.66	2.79	2.87
2050	3.37	3.10	3.70	3.37	2.94	2.84	3.44	3.40	2.78	2.93	3.13	3.21
2060	3.78	3.38	4.33	3.82	3.17	3.13	3.83	3.85	3.05	3.20	3.48	3.56
2070	4.12	3.60	4.96	4.29	3.33	3.39	4.17	4.31	3.30	3.47	3.82	3.91
2080	4.45	3.78	5.56	4.80	3.45	3.67	4.48	4.81	3.52	3.74	4.18	4.26
2090	4.74	3.86	6.12	5.34	3.53	3.94	4.74	5.34	3.70	4.01	4.57	4.63
2100	4.96	3.89	6.62	5.89	3.55	4.21	4.96	5.89	3.83	4.27	4.96	5.01

Bern-CC model (low) - CO2 radiative forcing (Wm-2)
Year	A1B	A1T	A1FI	A2	B1	B2	A1p	A2p	B1p	B2p	IS92a
2000	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49
2010	1.71	1.69	1.69	1.69	1.69	1.67	1.73	1.71	1.67	1.70	1.71
2020	2.04	1.95	2.01	2.00	1.95	1.89	2.09	2.03	1.91	1.97	1.99
2030	2.36	2.19	2.36	2.31	2.17	2.08	2.42	2.35	2.08	2.17	2.26
2040	2.69	2.48	2.83	2.68	2.41	2.30	2.76	2.71	2.27	2.38	2.55
2050	3.04	2.74	3.36	3.05	2.64	2.52	3.10	3.09	2.46	2.60	2.84
2060	3.37	2.96	3.91	3.44	2.81	2.74	3.39	3.46	2.67	2.81	3.14
2070	3.63	3.10	4.43	3.83	2.91	2.94	3.65	3.83	2.87	3.00	3.42
2080	3.89	3.19	4.94	4.27	2.98	3.16	3.89	4.26	3.03	3.21	3.74
2090	4.10	3.23	5.40	4.71	3.00	3.37	4.08	4.71	3.15	3.43	4.05
2100	4.27	3.20	5.81	5.20	2.99	3.59	4.23	5.19	3.24	3.65	4.39

Bern-CC model (high) - CO2 radiative forcing (Wm-2)
Year	A1B	A1T	A1FI	A2	B1	B2	A1p	A2p	B1p	B2p	IS92a
2000	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49	1.49
2010	1.88	1.85	1.85	1.85	1.84	1.84	1.91	1.88	1.84	1.87	1.88
2020	2.41	2.30	2.37	2.35	2.28	2.23	2.47	2.38	2.26	2.33	2.35
2030	2.96	2.78	2.97	2.89	2.73	2.62	3.04	2.94	2.64	2.75	2.82
2040	3.53	3.29	3.67	3.48	3.17	3.04	3.63	3.53	3.01	3.18	3.32
2050	4.11	3.77	4.44	4.09	3.59	3.46	4.20	4.13	3.39	3.59	3.82
2060	4.67	4.20	5.26	4.71	3.97	3.89	4.75	4.75	3.80	4.01	4.33
2070	5.18	4.57	6.04	5.33	4.27	4.29	5.23	5.36	4.19	4.39	4.82
2080	5.63	4.86	6.77	5.97	4.50	4.69	5.67	5.99	4.53	4.79	5.31
2090	6.04	5.07	7.45	6.61	4.67	5.08	6.06	6.62	4.80	5.17	5.80
2100	6.39	5.20	8.03	7.26	4.79	5.44	6.39	7.27	5.04	5.53	6.30

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