Guest “A funny thing happened on the way to the Anthropocene” by David Middleton

I’ve been studying a recent Holocene climate reconstruction (Kaufman, D., McKay, N., Routson, C. et al., 2020)… and I noticed a funny pattern…

Figure 1. “A funny thing happened on the way to the Anthropocene.”
  • I chose the “composite plus scale” version because it was the funniest.
  • I included a 100-yr average of HadCRUT4 and atmospheric CO2 from two Antarctic ice cores.
    • The resolution of the reconstruction is ~100-140 years.
    • The Law Dome ice core is high resolution, compatible with instrumental data.
    • They claim that the EPICA Dome C ice core is high resolution, but it isn’t.
  • I included the official Holocene subdivisions to show how the Anthropocene fits in.

Another funny thing happened on the way to the Anthropocene… All of this was likely to have been natural:

Figure 2. Look Ma… No SUV’s!

Why do I say this was likely to have been all natural?

Figure 3. Modeled human climate forcing compared to three instrumental records (see Terando for specifics)

I thought about writing a long post about the paper and the concept of resolution… and maybe I will later.

The full text and data of Kaufman, D., McKay, N., Routson, C. et al., 2020 are available online. It’s actually very well done.


Kaufman, D., McKay, N., Routson, C. et al. Holocene global mean surface temperature, a multi-method reconstruction approach. Sci Data 7, 201 (2020).

MacFarling Meure, C., D. Etheridge, C. Trudinger, P. Steele, R. Langenfelds, T. van Ommen, A. Smith, and J. Elkins. 2006. “The Law Dome CO2, CH4 and N2O Ice Core Records Extended to 2000 years BP”. Geophysical Research Letters, Vol. 33, No. 14, L14810 10.1029/2006GL026152. LINK Data

Monnin, E., et al.. 2004. EPICA Dome C Ice Core High Resolution Holocene and Transition CO2 Data.
IGBP PAGES/World Data Center for Paleoclimatology. Data Contribution Series # 2004-055.
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.

Terando, A., Reidmiller, D., Hostetler, S.W., Littell, J.S., Beard, T.D., Jr., Weiskopf, S.R., Belnap, J., and Plumlee, G.S., 2020, Using information from global climate models to inform policymaking—The role of the U.S. Geological Survey: U.S. Geological Survey Open-File Report 2020–1058, 25 p.,

And the inspiration for the post’s title…

via Watts Up With That?

March 23, 2021 at 08:46AM