Geoscience Reference
In-Depth Information
The chemical changes ( Fig. 13.6A , marked with
X) are measurable and happening now; the chemis-
try is very well known with good agreement
amongst datasets and experts, so certainty is high.
However, there is little evidence for biological
impacts ( Fig. 13.6A marked with
) of current ocean
acidii cation (and therefore little agreement and low
certainty) but that may be because there are no long-
term databases that look at this, or it could be
because current changes have had no impact. Thus,
as research in this area continues this assessment
could rapidly change.
Assessment of what could happen in the future to
ocean chemistry (Fig. 13.6B, marked with X) is
based on good understanding of ocean carbonate
chemistry and good agreement from circulation
models and dependent on the rate of future CO
2
emissions to the atmosphere. Assessment of what
could happen to biology in the future (Fig. 13.6B,
marked with
) is based on recent projections
(A)
What is already happening?
X
H
M
L
L
M
H
Amount of evidence (theory/observations/models)
What could happen from the increasing
acidification of the oceans in the future?
(B)
X
H
M
L
L
M
H
Amount of evidence (theory/observations/models)
High
Medium
Low
Figure 13.6
The Marine Climate Change Impacts Partnership (MCCIP) assessment of certainty based on level of agreement or consensus and the
amount of evidence for (A) what is happening now in terms of ocean acidii cation and (B) what could happen in the future. Assessments for current and
future chemical changes (X) are more certain than those for impacts now and in the future (
). See text for a detailed explanation (Turley et al. 2010b ).
