The recently released 2007 IPCC Statement for Policymakers (SPM) has received extensive media coverage, while a range of television shows (e.g. see) and even a Hollywood movie (An Inconvenient Truth) have promoted gloomy forecasts of the climate in coming decades.
We need an unambiguous litmus test which can be accepted by all credible climate scientists, however, to assess the magnitude of global warming on which these alarmist forecasts are based. As discussed in the paper
Pielke Sr., R.A., C. Davey, D. Niyogi, S. Fall, J. Steinweg-Woods, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim, H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, R.T. McNider, and P. Blanken, 2007: Unresolved issues with the assessment of multi-decadal global land surface temperature trends. J. Geophys. Res. in press,
the global average surface temperature trend has serious uncertainty and bias issues and is not the appropriate metric to use to assess global warming.
As discussed on Climate Science and Scitizen (e.g. see and see), the underlying reason for this aggressive campaign to focus on the human emissions of carbon dioxide from fossil fuels as the main culprit is to promote energy policy changes, not to develop an appropriate comprehensive climate policy.
There is a major risk, of course, in making CO2 the only villain in climate change, and in making definitive forecasts of what the climate will do in the coming decades. The risk is that if the IPCC forecasts do not occur as projected, then the credibility of the climate science community will be lost for a long time. This would be tragic as we need an effective climate policy to deal with the threats that climate variability and change pose to society.
Climate Science was launched in order to provide an alternative view on climate issues, which, if the IPCC projections fail, than there is a basis to move forward with a new direction, which Climate Science has proposed be a resource-based vulnerability framework; see
Pielke Sr., R.A., J.O. Adegoke, T.N. Chase, C.H. Marshall, T. Matsui, and D. Niyogi, 2007: A new paradigm for assessing the role of agriculture in the climate system and in climate change. Agric. Forest Meteor., Special Issue, 132, 234-254.
This weblog presents a global warming litmus test which can be used over the next several years to compare with the IPCC projections; the question is
What is the magnitude ocean heat storage changes each year?
For global warming to occur, the heat, as measured in Joules, needs to increase each year.
The heat accumulation for the period from 2002 to the present and into the future needs to be a high priority. For example to sustain a global warming rate of 1 Watt per meter squared since 2002 for the following ten years requires the accumulation of 1.6 *10**23 Joules within the climate system.
A figure, such as Figure 8 in Willis, J.K., D. Roemmich, and B. Cornuelle, 2004: Interannual variability in upper ocean heat content, temperature, and thermosteric expansion on global scales. J. Geophys. Res., 109, C12036, doi: 10.1029/2003JC002260.
should be widely communicated each year (or more frequently). For example, as a requirement to NOT reject the IPCC claim for global warming, Climate Science proposes that on the scale presented in Figure 3 in Willis et al, the left axis in their Figure 8 must exceed the following values in each year
2003 8*10**22 Joules
2004 9*10**22 Joules
2005 10*10**22 Joules
2006 11*10**22 Joules
2007 12*10**22 Joules
2008 13*10**22 Joules
2009 14*10**22 Joules
2010 15*10**22 Joules
2011 16*10**22 Joules
2012 17*10**22 Joules
This is actually quite a conservative test for the IPCC since the radiative imbalance (which includes all radiative forcings and feedbacks; see), and thus the actual ocean heat storage changes should be larger.
With the expected updating of the 2003 up to the present data (see), we should soon be able to present the actual values of global warming (or global cooling) to compare with the hypothesized radiative imbalances presented above.
Will the IPCC and others in the climate community, and those who are using climate trends to promote energy policy adopt and advocate for this diagnostic of global warming? If they are honest climate scientists they would (see also).