Read a data file holding sea level data. BUG: the time vector assumes GMT, regardless of the GMT.offset value.

read.sealevel(
  file,
  tz = getOption("oceTz"),
  processingLog,
  debug = getOption("oceDebug")
)

Arguments

file

a connection or a character string giving the name of the file to load. See Details for the types of files that are recognized.

tz

time zone. The default value, oceTz, is set to UTC at setup. (If a time zone is present in the file header, this will supercede the value given here.)

processingLog

if provided, the action item to be stored in the log. (Typically only provided for internal calls; the default that it provides is better for normal calls by a user.)

debug

an integer specifying whether debugging information is to be printed during the processing. This is a general parameter that is used by many oce functions. Generally, setting debug=0 turns off the printing, while higher values suggest that more information be printed. If one function calls another, it usually reduces the value of debug first, so that a user can often obtain deeper debugging by specifying higher debug values.

Value

A sealevel object.

Details

This function starts by scanning the first line of the file, from which it determines whether the file is in one of two known formats: type 1, the format used at the Hawaii archive centre, and type 2, the comma-separated-value format used by the Marine Environmental Data Service. The file type is inferred by examination of its first line. If that contains the string Station_Name the file is of type 2. If the file is in neither of these formats, the user might wish to scan it directly, and then to use as.sealevel() to create a sealevel object. The Hawaii archive site at http://ilikai.soest.hawaii.edu/uhslc/datai.html at one time provided a graphical interface for downloading sealevel data in Type 1, with format that was once described at http://ilikai.soest.hawaii.edu/rqds/hourly.fmt (although that link was observed to no longer work, on December 4, 2016). Examination of data retrieved from what seems to be a replacement Hawaii server (https://uhslc.soest.hawaii.edu/data/?rq) in September 2019 indicated that the format had been changed to what is called Type 3 by read.sealevel. Web searches did not uncover documentation on this format, so the decoding scheme was developed solely through examination of data files, which means that it might be not be correct. The MEDS repository (http://www.isdm-gdsi.gc.ca/isdm-gdsi/index-eng.html) provides Type 2 data.

See also