There is a clear mismatch between the model predictions reported in the 2005 Science article by Hansen, J., L. Nazarenko, R. Ruedy, Mki. Sato, J. Willis, A. Del Genio, D. Koch, A. Lacis, K. Lo, S. Menon, T. Novakov, Ju. Perlwitz, G. Russell, G.A. Schmidt, and N. Tausnev 2005. “Earth’s energy imbalance: Confirmation and implications” , and the observational results in the Geophysical Research Letters paper by John M. Lyman, Josh K. Willis, and Gregory C. Johnson entitled âRecent Cooling of the Upper Oceanâ?.
The abstract of the Hansen et al article reads,
“Our climate model, driven mainly by increasing human-made greenhouse gases and aerosols among other forcings, calculates that Earth is now absorbing 0.85Â±0.15 W/m2 more energy from the Sun than it is emitting to space. This imbalance is confirmed by precise measurements of increasing ocean heat content over the past 10 years. Implications include: (i) expectation of additional global warming of about 0.6Â°C without further change of atmospheric composition; (ii) confirmation of the climate system’s lag in responding to forcings, implying the need for anticipatory actions to avoid any specified level of climate change; and (iii) likelihood of acceleration of ice sheet disintegration and sea level rise.”
However, the new Lyman et al 2006 study which also is based on the same “precise measurements of increasing ocean heat content” report that the global radiative imbalance for 1993 through 2005, for the entire 13-year period, was an average warming rate of 0.33 Â± 0.23 W/m2 , as a result of the 2003 to 2005 period which has a diagnosed radiative imbalance of -1.0 (+/- 0.3) W/meter squared.
The Comments on the Climate Science weblog with respect to earlier weblogs on the Lyman et al 2006 paper (see and see) include raising the issue on the relationship of this recent cooling to the reported continuing rise in the global average sea level. This is an appropriate scientific question.
However, if the upper ocean heat content data was considered precise in the Hansen et al 2005 study, and was used in that paper to bolster the confidence in their ability to model global climate process, then the same confidence should be placed on the recent diagnosis of observed cooling. The mismatch between the data and the model predictions, however, raises serious questions on the ability of the multi-decadal global climate models to accurately predict even the global average variability and long term trend of the radiative imbalance of the climate system.