0)
0
60
50
40
30
20
10
-1 0
- 20
bO
145
I in. t rend sst (deg C/ 10y) 1949-1991
120
1BO
240
300
3bO
- 30~~L-f-~-r~~r-~a,~--~~-r~~~~-+l---r--1-r~~~~~
o
60
120
100
300
360
exp. vdr . ssl re I. lo ssl lre n d
b) 0
bO
120
100
240
300
360
o
60
120
1BO
240
300
360
60
50
40
30
20
10
0
- 10
- 20
- 30
60
50
40
30
20
10
0
- 10
- 20
-30
Figure 31: Spatial distribution of linear trend coefficients of observed SST (degrees 0/
decade) for the period 1949-1991 . b) Variances explained in SST by the linear trends.
From Latif, et al (1996).
6.2 Is the observed surface warming due to the greenhouse effect?
If the analysis in the preceeding section is correct, then the answer to
this question is, in large measure, no. The greenhouse effect is a purely
radiative mechanism, whilst much of the observed warming is, according
to our nonlinear paradigm, the result of changes in large-scale dynamics in
which certain regimes have become anomalously populated. In this picture,
the warming is a property of the anomalous surface temperature associated
with the regimes in Fig lla,c.