Another example from Climate Science:
The 2007 IPCC Statement for Policymakers has a significant error that I have yet to see discussed. The
SPM reports on a “Total Net Anthropogenic” global average radiative
forcing for 2005 of +1.6 [0.6 to 2.4] Watts per meter squared. When one
converts the units, this means that the Earth’s climate system should
be accumulating Joules at a rate of 2.61*10**22 Joules per year
[0.98*10**22 Joules to 3.91*10*22 Joules per year] in 2005. The
data, however, show quite a different accumulation of Joules in recent
years, and in 2005 in particular. We have often argued that the ocean
data has been shown to be an effective way to diagnose the radiative
imbalance (see and see).
Jim Hansen, for example, has used the accumulation of heat in the upper
oceans in the 1990s to bolster his claim of multi-decadal global
climate prediction skill (see), where Jim Hansen wrote, “The
Willis et al. measured heat storage of 0.62 W/m2 refers to the decadal
mean for the upper 750 m of the ocean. Our simulated 1993-2003 heat
storage rate was 0.6 W/m2 in the upper 750 m of the ocean. The decadal
mean planetary energy imbalance, 0.75 W/m2, includes heat storage in
the deeper ocean and energy used to melt ice and warm the air and land.
0.85 W/m2 is the imbalance at the end of the decade.” He further writes with respect to the radiative forcing record, “As
the record lengthens, the energy imbalance will provide an invaluable
metric defining the task that humanity faces if it wishes to stabilize
global climate.” Well the radiative forcing data record is now
longer, and it presents quite a different perspective than a
more-or-less monotonic increase in the global radiative forcings as
claimed by Jim Hansen. As shown in Lyman, J. M., J. K. Willis, and G. C. Johnson (2006), Recent cooling of the upper ocean, “We
observe a net loss of 3.2 (±1.1) × 10**22 J of heat from the upper
ocean between 2003 and 2005. Using a broad array of in situ ocean
measurements, we present annual estimates of global upper-ocean heat
content anomaly from 1993 through 2005. Including the recent downturn,
the average warming rate for the entire 13-year period is 0.33 ± 0.23
W/m2 (of the Earth’s total surface area)….” See their Figure 1 where the accumulation and loss of heat as measured in Joules for the period 1993 to mid-2005 is shown. This
loss of heat from the upper oceans is also consistent with little if
any heating in the troposphere over the last several years (e.g. see the last several years in Figure 7
where the trends in the global average tropospheric and stratospheric
temperatures are essentially zero). Even if the heat has been
transported deeper into the ocean than the about 700m depth analyzed by
Lyman et al, the radiative forcing that is available to alter the
global average surface temperature trend is much less than reported in
the 2007 IPCC SPM, and, indeed, for at least the period from 2003 to
2005 is a negative forcing! Thus, the data indicate a very different
picture than presented by the IPCC. The global average surface temperature trend in the 2007 SPM (see Figure SPM-3 top in the IPCC SPM) continues to show warming, but as has been summarized in Pielke
Sr., R.A., C. Davey, D. Niyogi, K. Hubbard, X. Lin, M. Cai, Y.-K. Lim,
H. Li, J. Nielsen-Gammon, K. Gallo, R. Hale, R. Mahmood, S. Foster, J.
Steinweg-Woods, R. Boyles, S. Fall, 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, there is a significant warm bias in the construction of a global average surface temperature trend. What
these observations mean is that the statement in the IPCC SPM that
there is a positive radiative forcing of 1.6 [0.6 to 2.4] Watts per
meter squared in 2005 (when this was not true based on real
data) is a particularly egregious error. Rather than relying solely on
model based estimates to calculate a global radiative forcing, the
authors of the IPCC Report should have also used real world data for
the assessment of the net radiative forcing. A claim that a
time period of several years is too short to assess the radiative
heating is spurious as long as the sampling of the ocean heat content
is sufficiently dense. As discussed in Pielke Sr., R.A., 2003: Heat storage within the Earth system. Bull. Amer. Meteor. Soc., 84, 331-335, “A
snapshot at any time documents the accumulated heat content and its
change since the last assessment. Unlike temperature, at some specific
level of the ocean, land, or the atmosphere, in which there is a time
lag in its response to radiative forcing, there are no time lags
associated with heat changes.” The IPCC finding that the total
2005 net anthropogenic radiative forcing has a best estimate of +1.6
Watts per meter squared and that the total 2005 net radiative forcing
has a best estimate of +1.72 Watts per meter squared is inconsistent
with the observed changes in upper ocean heat content. The omission of
a discussion of the conflict between real world observations and the
model estimates of radiative forcing is a serious error in the IPCC SPM.
Geophys. Res. Lett., 33, L18604, doi:10.1029/2006GL027033.