<<  <  >  >>

Table 6

Ecological Indicators

Unit of

Base

Indicator

Measurement

1990

A1FI

A2

B2

B1

CO2 concentration (in 2100)

ppm

353

970

856

621

549

Net carbon sink capacity with

climate change (in 2100)

Pg C/yr

0.7

5.8

5.9

3.1

2.4

Area of cropland with climate change

% of global

(in 2100)

land area

11.6

5.0

NA

13.7

7.8

Losses of coastal wetlands due to sea

% of

level rise alone (1990­2085)

current area

5­20

3­14

3­15

4­16

Losses of coastal wetlands due

% of

to other causes (1990­2085)

current area

32­62

32­62

11­32

11­32

Combined losses of coastal

% of

wetlands (1990­2085)

current area

35­70

35­68

14­42

14­42

Sources: Nigel W. Arnell et al., "The Consequences of CO2 Stabilization"; Indur M. Goklany and David A. King,

"Climate Change and Malaria," Letter, Science 306 (2004); Robert J. Nicholls, "Coastal Flooding and Wetland Loss in

the 21st Century: Changes under the SRES Climate and Socio-Economic Scenarios," Global Environmental Change

14, no. 1, (2004): 69­86; and P. E. Levy et al., "Modeling the Impact of Future Changes in Climate, CO2 Concentration

and Land Use on Natural Ecosystems and the Terrestrial Carbon Sink," Global Environmental Change 14, no. 1 (2004):

21­30.

variability, and its health effects are

wetland losses are much higher for the A1FI

confounded by simultaneous changes

scenario than for the B1 and B2 scenarios, but

in many other influences on popula-

this is due mainly to the assumption that

tion health. . . . Empirical observation

under A1FI, societies would take fewer or less

of the health consequences of long-

effective measures to alleviate non-climate-

term climate change, followed by for-

change-related subsidence which, as noted, is

suspect.54

mulation, testing and then modifica-

tion of hypotheses, would therefore

require long time-series (probably sev-

Is Climate Change

eral decades) of careful monitoring.

the Most Important

While this process may accord with the

canons of empirical science, it would not pro-

Environmental Problem for

vide the timely information needed to

the Foreseeable Future?

inform current policy decisions on GHG

emission abatement, so as to offset possible

health consequences in the future.56

A review paper in Nature claims that glob-

al warming may have been responsible for

about 0.17 million deaths worldwide in

In other words, the 0.17 million estimate

2000.55 This estimate is based on an analysis

should be viewed with skepticism since science

was admittedly sacrificed in hot pursuit of a

which was put out under the auspices of the

predetermined policy objective. But, absent

World Health Organization. However, the

One cannot base

serendipity, one cannot base sound policy on

authors of that analysis acknowledge that

poor science.

sound policy on

Nevertheless, for the purposes of this

climate change occurs against a back-

poor science.

paper, I will accept this problematic estimate

ground of substantial natural climate

12