The “trick” has not benign, given it consisted of pretty blatant data cooking.
DISCLAIMER: literally the only thing I know about this is the code on the linked page.
I’m not sure thats true. The code you linked to seems to be implementing this correction pretty much directly from the literature:
Briffa, K.R., Schweingruber, F.H., Jones, P.D., Osborn, T.J., Shiyatov, S.G. and Vaganov, E.A., 1998
“Reduced sensitivity of recent tree growth to temperature at high northern latitudes.”
Nature 391, 678-682 (R)
(I found it by taking the name of the file briffa_sep98 and googling for a few minutes). I know nothing about tree-rings, but its a nature paper, so I assume the authors know about tree-rings. I can’t verify how correctly its implemented because I’m not going to trace the code leading into this routine to check the units for the tree ring thickness being adjusted..
The code in question seems to output a line on a graph labled “Northern Hemisphere MXD corrected for decline.”
So as far as I can tell there isn’t a lot of scientific misconduct going on- they took a data-correction from the literature (anyone know if its a standard correction?), coded it up, and labled the line on the graph as implementing the correction. The uncorrected line is also output by the code on to the same graph.
Or are we considering that the Briffa correction itself is cooking the data? If so shouldn’t the discussion center around the published paper and where it goes wrong?
The “trick” (“Mike’s Nature trick”) refers to a technique for plotting reconstructed temperatures (from tree rings) together with recent direct measurements, apparently simply by drawing them in different colours. The code you linked above is a separate technique (labelled “hiding the decline”), a correction for an anomalous decline in tree ring growth, which before 1960 had been closely correlated with temperature. It is speculated that the decline in tree ring growth is due to air pollution or other anthropogenic causes. See here for more detail.
The “trick” has not benign, given it consisted of pretty blatant data cooking.
DISCLAIMER: literally the only thing I know about this is the code on the linked page.
I’m not sure thats true. The code you linked to seems to be implementing this correction pretty much directly from the literature:
Briffa, K.R., Schweingruber, F.H., Jones, P.D., Osborn, T.J., Shiyatov, S.G. and Vaganov, E.A., 1998 “Reduced sensitivity of recent tree growth to temperature at high northern latitudes.” Nature 391, 678-682 (R)
(I found it by taking the name of the file briffa_sep98 and googling for a few minutes). I know nothing about tree-rings, but its a nature paper, so I assume the authors know about tree-rings. I can’t verify how correctly its implemented because I’m not going to trace the code leading into this routine to check the units for the tree ring thickness being adjusted..
The code in question seems to output a line on a graph labled “Northern Hemisphere MXD corrected for decline.”
So as far as I can tell there isn’t a lot of scientific misconduct going on- they took a data-correction from the literature (anyone know if its a standard correction?), coded it up, and labled the line on the graph as implementing the correction. The uncorrected line is also output by the code on to the same graph.
Or are we considering that the Briffa correction itself is cooking the data? If so shouldn’t the discussion center around the published paper and where it goes wrong?
The “trick” (“Mike’s Nature trick”) refers to a technique for plotting reconstructed temperatures (from tree rings) together with recent direct measurements, apparently simply by drawing them in different colours. The code you linked above is a separate technique (labelled “hiding the decline”), a correction for an anomalous decline in tree ring growth, which before 1960 had been closely correlated with temperature. It is speculated that the decline in tree ring growth is due to air pollution or other anthropogenic causes. See here for more detail.