get_nc_online: get_nc_online

In RetoSchmucki/climateExtract: Extract Climate Data From a Local or online NETCDF

get_nc_online

Description

Download and connect climate data from NetCDF file (.nc) retrieved from https://surfobs.climate.copernicus.eu/dataaccess/access_eobs.php

Usage

get_nc_online(
  first_year = first_year,
  last_year = last_year,
  sml_chunk = sml_chunk,
  clim_variable = clim_variable,
  statistic = statistic,
  grid_size = grid_size,
  ecad_v = ecad_v
)

Arguments

first_year	a numeric value defining the first year of the time period to extract, 1950 if NULL, default=NULL
last_year	a numeric value defining the last year of the time period to extract, 2014 if NULL, default=NULL
sml_chunk	a character string for specific time period to be downloaded. Chunk available are "2011-2024", "1995-2010", "1980-1994", "1965-1979", and "1950-1964"
clim_variable	a character string defining the daily climate variable to retrieve and extract; "mean temp", "max temp", "min temp", "precipitation", "sea level pressure", "relative humidity", "global radiation", default="mean temp"
statistic	a character string defining the metric to retrieve, "mean" or "spread", where the mean is computed across 100 members of the ensemble and is provided as the "best-guess" fields. The spread is calculated as the difference between the 5th and 95th percentiles over the ensemble to provide a measure indicative of the 90% uncertainty range (see details)
grid_size	numeric, measured in degree defining the resolution of the grid, 0.25 (ca. 27 kilometres in latitude) or 0.1 (ca. 11 kilometres in latitude), default=0.25
ecad_v	ECA&D data version, default = package version.

Details

This function access online ECAD data portal to download the climate ".nc" file to local disk. This is an internal function used within the 'extract_nc_value' function, but can be used independently if needed. If first_year and last_year are not provided, the function extract the full data set. Smaller chunks of about 15 years of the most recent version of the E-OBS dataset can be specified for download can be specified directly with the argument "sm_chunk" (period available are 2011-2022, 1995-2010, 1980-1994, 1965-1979, 1950-1964). For more details about the mean and the spread metric see Cornes et al. (2018) and the guidance on how to use ensemble datasets available from http://surfobs.climate.copernicus.eu/userguidance/use_ensembles.php

Value

A connection via the ncdf4 package to a ".nc" file downloaded to the local disk

Author(s)

Reto Schmucki

RetoSchmucki/climateExtract documentation built on July 3, 2025, 11:39 p.m.