TrenchNoise: Trench noise spectrum

In EarthSystemDiagnostics/proxysnr: Separate Signal and Noise in Climate Proxy Records

Trench noise spectrum

Description

Internal function to obtain estimates of the noise spectrum at the local scale at EDML using the available isotope data from the shallow trench profiles from Münch et al. (2017). To convert the trench depth axis into a time axis, a constant accumulation rate with a given uncertainty is assumed.

Usage

TrenchNoise(
  acc.rate = 25,
  sigma.acc.rate = 5,
  res = 3,
  neff = 19,
  df.log = 0.1
)

Arguments

acc.rate	assumed mean accumulation rate at the trench site [cm/yr]
sigma.acc.rate	assumed uncertainty of the accumulation rate [cm/yr]
res	depth resolution of the trench data; defaults to 3 cm.
neff	effective number of trench records to account for the spatial autocorrelation of the stratigraphic noise; defaults to 19 for the total available number of 22 profiles (Münch et al., 2017).
df.log	Gaussian kernel width in log space to smooth the spectral estimate; defaults to 0.1.

Value

A list of the three components, each of class "spec":

noise.lower:

spectral object list with the estimated trench noise spectrum for the assumed lower bound of the accumulation rate.

noise.mean:

as previous but for the assumed mean accumulation rate.

noise.upper:

as previous but for the assumed upper bound of the accumulation rate.

Author(s)

Thomas Münch

References

Münch, T. and Laepple, T.: What climate signal is contained in decadal- to centennial-scale isotope variations from Antarctic ice cores? Clim. Past, 14, 2053–2070, https://doi.org/10.5194/cp-14-2053-2018, 2018.

EarthSystemDiagnostics/proxysnr documentation built on Sept. 15, 2024, 7:47 a.m.