Understanding the role of the ocean in climate change and
making decadal climate forecasts will be greatly enhanced by observations planned as part of an international Global Ocean Observing System.
Not exact matches
Specifically, he addressed a claim
made by Will Happer, a Princeton professor, that no models demonstrate
decadal variability in trends (which was not the case), and explored in depth the signal to noise ratio in determining
climate trends much more comprehensively than had been done previously.
«What's really been exciting to me about this last 10 - year period is that it has
made people think about
decadal variability much more carefully than they probably have before,» said Susan Solomon, an atmospheric chemist and former lead author of the United Nations»
climate change report, during a recent visit to MIT.
One notable point is that I received no pushback from anyone for my statements on the value of the 21st century
climate models to support water decision
making, and the usefulness of the PDO and AMO on
decadal time scales.
Julia Slingo
makes it clear that the BBC report confused the public with their headline because it conflated a
decadal prediction with
climate change.
I agree that the ambition to
make (regional)
climate predictions even at
decadal or longer time scales can not be supported by the current apparent feasibility, given the studies that demonstrate the lack of predictive skill.
However, direct attribution of these changes to
climate change is
made difficult by long - term patterns of variability that influence productivity of different parts of the Ocean (e.g., Pacific
Decadal Oscillation).
When using
climate information to support decision
making on
decadal to century timescales, we are in a situation of «deep uncertainty;» see the previous post on Can we
make good decisions under ignorance?
The key is accurately representing the large - scale ocean circulation and associated heat transport in the
climate models used to
make the
decadal predictions.
Girma; the point we are
making is that
climate models DO N'T predict the timing of short term (
decadal) pauses or accelerations.
But VTG's numbers indicate that you
made that statement even when the paper you was in the process of getting published indicates that ACO2 in fact dominated
climate on a
decadal scale over the past 6 decades or so.»
But VTG's numbers indicate that [Judith]
made that statement even when the paper [she co-authored and] was in the process of getting published indicates that ACO2 in fact dominated
climate on a
decadal scale over the past 6 decades or so.»
Unforced variability of global temperature is great, as shown in Figure 4, but the global temperature trend on
decadal and longer time scales is now determined by the larger human -
made climate forcing.
There is currently less skill in predicting precipitation and other variables compared to temperature although progress is expected to be
made as a consequence of the
Decadal Climate Prediction Project (DCPP) and other projects and investigations.
* Bearing in mind the accommodation with nature that humans need to
make with even relatively short periods of «different to normal» weather, perhaps it might be more useful for the authorities to consider «noticeable»
climate change as covering
decadal rather than 30 year periods
The NSF program on
climate dynamics has
made over 200 awards, most if not all seasonal to
decadal.
The authors commented «This implies that the current [
climate] models are ill - suited to localised
decadal predictions, even though they are used as inputs for policy
making.»»
A myopic tropopsheric focus on «
climate» sensitivity, especially on anything less than
decadal average timeframes, simply does not
make sound scientific sense.
At this point it is possible to attempt a full forecast of the
climate since 2000 that is
made of the four detected
decadal and multidecadal cycles plus the corrected anthropogenic warming effect trending.