### Chronology

*In these uncertain times... we need better statistics.*

- Cristi Proistosescu developed a framework to better understand when orbital tuning should help improve the accuracy of a chronology (2012).
- Another topic is how time uncertainty affects spectral analysis or marine proxy records (2004) and Martian polar layer deposits (2009). Basically, time errors smear the energy in spectral peaks across frequency. Andy Rhines showed, however, that timing errors do not much affect estimates of power-law distributions (2011).
- Eddie Haam developed an order statistics method to test for covariance between time-uncertain records (2010).
- Oded Aharonson and I showed that finding eccentricity-like amplitude modulation in tuned records is a poor test of time accuracy (2010). It turns out that imposing the frequency modulations found in climatic precession through tuning and then filtering tends to give eccentricity-like amplitude modulation. Dynamically, this is because the stability of the phase of precession depends upon the magnitude of eccentricity.
- Also of interest has been developing chronologies of Pleistocene glaciation that are independent of orbital assumptions (2004, 2007).

### References

- Proistosescu, Huybers and Maloof
*To Tune or not to Tune: Detecting Orbital Variability in Oligo-Miocene Climate Records*, Earth and Planetary Science Letters, 2012. pdf - Rhines and Huybers,
*Estimation of spectral power laws in time-uncertain series of data with application to the GISP2 delta-18O record*, Journal of Geophysical Research, 2011. pdf - Huybers and Aharonsen,
*Orbital tuning, eccentricity, and the frequency modulation of climatic precession*, Paleoceanography, 2010. pdf - Perron and Huybers,
*Is there an orbital signal in the polar layered deposits on Mars?*, Geology, 2009. pdf - Haam and Huybers,
*A test for the presence of covariance between time-uncertain series of data with application to the Dongge Cave speleothem and atmospheric radiocarbon records*, Paleoceanography, 2010. pdf - Huybers,
*Glacial variability over the last 2Ma: an extended depth-derived agemodel, continuous obliquity pacing, and the Pleistocene progression*, Quaternary Science Reviews, 2007. pdf and (supplemental material posted at NCDC) - Huybers and Wunsch,
*A depth-derived Pleistocene age-model: uncertainty estimates, sedimentation variability, and nonlinear climate change,*Paleoceanography, 2004. pdf

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