PALMODutils

example R code to interact with the PALMOD 130k marine palaeoclimate data synthesis version 2 (to be released soon). The contents of version 1 of the data product are described in detail in https://doi.org/10.5194/essd-2019-223. Version 1 data are available for download at https://doi.pangaea.de/10.1594/PANGAEA.908831. The links to the data and the data descriptor for version 2 will be mentioned here in due time. This code cannot be used to anymore to query previous versions of the data product (use the initial commit instead).

Querying the data

The function queryPALMOD() allows querying of the data by:

• geographical range
• ocean basin
• parameter
• parameter detail
• sensor species
• age range
• minimum lenght (within the age range)
• minimum number of data points
• maximum time between data points
• minimum number of age control points

The function searches within calendar age expressed as ka BP or kyr.

A complete parameter list can be found in Table 4 of https://doi.org/10.5194/essd-2019-223. Specifying parameter detail makes most sense when filtering near surface temperature estimates (using for instance: MgCa, UK37 or planktonic foraminifera assemblage).

The function either returns TRUE/FALSE indicating whether the query criteria are met when extract_data = FALSE (default) or a tibble with the (meta)data when extract_data = TRUE

queryPALMOD() should be applied over a vector that contains the location of the individual files, which can be created with:

PALMOD130k_V2_0_0 <- list.files("path", full.names = TRUE)

example to query the data

source("queryPALMOD.R")
meetsCrit <- queryPALMOD(sites = PALMOD130k_V2_0_0,
                         Parameter = "planktonic.d18O",
                         ParameterDetail = NULL,
                         SensorSpecies = NULL,
                         lat_min = -90,
                         lat_max = 90,
                         lon_min = -180,
                         lon_max = 180,
                         ocean_basin = NULL,
                         age_min = 0,
                         age_max = 2,
                         min_n_obs = 50,
                         min_duration = 0, 
                         max_sample_interval = Inf, 
                         min_n_tiepoint = 3,
                         extract_data = TRUE
                         )

Uncertainty estimate of near sea surface temperature

The function nsst_joint_uncertainty calculates time series of near sea surface temperature including the joint uncertainty of age and calibration. It randomly selects n_ens_pairs from the 10⁶ possible combinations of the age and temperature ensembles and calculates summary statistics for age (median) and near sea surface temperature. The output is a tibble with details about the proxy sensor and the calibration and the 5%, 25%, 50%, 75% and 95% quantiles of nsst.

example to estimate uncertainty of near sea surface temperature

source("nsst_joint_uncertainty.R")
nsst_joint_uncertainty(PALMOD130k_V2_0_0[1], n_ens_pairs = 1e3)