Geoscience Reference
In-Depth Information
2500
SRES
Baseline
Mitigation
25
2000
20
15
1500
10
1000
5
500
0
-5
(A)
(B)
0
1000
5
900
4
800
3
700
600
2
500
1
400
(D)
(C)
0
300
3.4
8.2
3.1
8.1
2.8
8.0
2.5
7.9
2.2
7.8
1.9
(E)
(F)
1.6
7.7
1980
2000
2020
2040
2060
2080
2100
1980
2000
2020
2040
2060
2080
2100
Year
Year
Figure 14.2 (A) Annual and (B) cumulative CO 2 emissions prescribed in the Bern2.5CC model and projected (C) atmospheric CO 2 , (D) changes in
global-mean surface air temperature, (E) global average surface saturation with respect to CaCO 3 in the form of aragonite, and (F) global average surface pH
on the total pH scale (pH T ). Baseline scenarios are shown by red lines and mitigation scenarios by blue dotted lines. The SRES high-emissions A2 and
low-emissions B1 marker scenarios are given by black lines. Bars indicate uncertainty ranges for the year 2100 and for the four representative concentration
pathways (RCPs), marked for evaluation by climate modellers in preparation for the IPCC Fifth Assessment Report. The ranges were obtained by combining
different assumptions about the behaviour of the CO 2 fertilization effect on land, the response of soil heterotrophic respiration to temperature, and the
turnover time of the ocean, thus approaching an upper boundary of uncertainties in the carbon cycle, and additionally accounting for the effect of varying
climate sensitivity from 1.5 to 4.5°C (Joos et al. 2001 ).
 
Search WWH ::




Custom Search