Future research II: Do
models systematically underestimate ÒobservedÓ ocean
temperature variability?
Time-variability of ÒcompleteÓ ocean
temperature data (¡C)
Source: AchutaRao et al., PNAS (2007)
Models with
volcanoes
Models without
volcanoes
Detecting ÒsignificantÓ climate
change means showing that a given change in climate is unusual relative to
some yardstick that you have of ÒnormalÓ behavior.
If you feel hot, and measure a body
temperature of 102oF, then youÕve ÒdetectedÓ a fever - you know
that that this elevated temperature is outside the limits of ÒnormalÓ body
temperature.
But this measurement doesnÕt give you
the cause of the fever.
To deduce the cause, youÕll probably
need to undergo some more sophisticated tests - perhaps urine and blood
analyses, maybe even x-rays or CAT scans.
Once you have the results from these
tests, itÕs much easier to narrow down the potential causes of the fever.
This is attribution - the process of
establishing cause and effect.