This post relates to a challenge posed by Gavin at Real Climate, to better depict the long term history of temperature. Gavin linked to datasets ranging from instrumental (150 years) to Phanærozoic (540 M yrs). I have been experimenting with user-adjustable graphs (see also gallery). The big changes of scale are a challenge, but I thought it was worth a try. The current version is rough, but I'll put in more data, with selectable axes.
The graph initially shows the last 200 years or so, but with a temperature scale big enough to cover the whole period. You can adjust the scales as follows:
- Translation - by mouse dragging in the plot space. However, zero time (before 2014) is fixed to the origin.
- Temp scale - by dragging vertically in the space to the left of the y-axis.
- Time scale - this is the critical one. You can make fine adjustments by dragging below the x-axis. But faster is to click in the region with <...>, blue, bottom left. < shrinks the scale (longer times), and the response is proportional to how far you click from the centre (about double per <).
| Period | Reference | Data download |
| 0-600 Mya | Veizer et al (2000), Royer et al (2004) (updated Royer (2014)) | Veizer d180, Royer04 Temp, Royer14 CO2 |
| 0-65 Mya | Zachos et al (2008), Hansen et al (2010) | Zachos/Hansen |
| 0-5.3 Mya | Lisiecki and Raymo (2005) | LR04 Stack |
| 0-800 kya | EPICA Dome C | Temperature Reconstruction |
| 0-125 kya | NGRIP/Antarctic analog? | NGRIP 50yr |
| 0-12 kya | Marcott et al (2013) | MEA12 stack (xls) |
| 0-2 kya | Mann et al (2008), Ljungqvist (2010) | MEA08 EIV, Ljungqvist10 |
| 1880-2013 CE | GISTEMP | GISTEMP LOTI |
| 1850-2013 CE | HadCRUT4 | HadCRUT4 Global annual average, Cowtan&Way (infilled) |
| 1850-2013 CE | Berkeley Earth | Land+Ocean annual mean |
I have currently done HadCRUT4, GISTEMP LOTI, Ljungqvist10, Marcott et al (2013), EPICA Dome C,Lisiecki and Raymo (2005), Zachos and Hansen, Veizer d180. L&R is d190O data, so I scaled to to match Z&H over the first 5 million years. Veizer is ocean bottom temperature, so I used a faint color - I'm currently just trying to get the scaling to work well. So here is the plot:
Update: As Gavin at RC noted, I had L&R upside (d18O). Fixed now.
Other imperfections
I haven't been careful with anomaly base - the data is as is. I tried adjusting sequentially by overlaps, but there is noise, and for the moment, I don't think it adds value.I have smoothed and sampled opportunistically. Epica was smoothed by three boxcar filterings, length 5, and then sampling every fifth. Zachos was smoothed once and sampled every fifth. L&R was sampled. With smoothing, end regions were included unsmoothed.
I'll surely find more.
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