| sealevel {oce} | R Documentation |
This sample sea-level dataset is the 1999
record from Halifax Harbour
in Nova Scotia, Canada.
The code in read.sealevel was written based on examination of
this and similar files.
data(sealevel)
The data format is as described below, taken from ftp://ilikai.soest.hawaii.edu/rqds/hourly.fmt.
UH SEA LEVEL CENTER/JOINT ARCHIVE FOR SEA LEVEL
'ARCHIVING' FORMAT
FOR HOURLY SEA LEVEL DATA
The hourly data consist of files grouped by year that
have been "zipped" into a single file per time series.
The Info-Zip web site is at: http://www.cdrom.com/pub/infozip
and the software can be directly downloaded from
ftp://ftp.cdrom.com/pub/infozip/. This freeware zip
utility is compatible to most platforms and operating
systems. For MS-DOS systems, use the -aa option
during unzipping. This will add the Carriage Return-
Line Feed end-of-record sequence.
FILE NAME CONVENTION:
Each file is given a name hsssv.dat where sss denotes the
the UHSLC/JASL inhouse station number and v denotes the version.
For example, h003b.dat is the 1987 observed daily data file in
the permanent archive for Baltra-B. Baltra is a station with
more than one independent series due to a station replacement
that is not linked to the bench marks of the original station.
FORMAT DESCRIPTION:
A file exists for all years with data and every hourly value
in the year contains either data or a missing data flag (9999).
If complete years are missing between data values, then all
records for those years are filled with missing data flags, as well.
One header exists at the start of each year. All records are fixed-length,
80-byte.
The unique header for each file is coded as:
field bytes length comment
----------------- ------- ------ ------------------------------------
station number 1-3 3 exactly 3 digits
station version 4 1 letter from A to Z
station name 6-23 18 Abbreviated if necessary
region/country 25-43 19 Abbreviated if necessary
year 45-48 4
latitude 50-55 6 degrees, minutes, tenths
(implied decimal), and hemisphere
longitude 57-63 7 degrees, minutes, tenths
(implied decimal), and hemisphere
GMT offset 65-68 4 time data are related to in terms
of difference from GMT in hours
and tenths (implied decimal) with
East latitudes positive*
decimation method 70 1 Coded as 1 : filtered
2 : simple average of all
samples
3 : spot readings
4 : other
reference offset 72-76 5 constant offset to be added to each
each data value for data to be
relative to tide staff zero or primary
datum in same units as data
reference code 77 1 R = data referenced to datum
X = data not referenced to datum
units 79-80 2 always millimeters, MM
* Data always are in GMT (offset=0000) unless data are relative to a local
time zone that is not an increment of one hour from GMT. For example,
Colombo, Sri Lanka has a GMT offset = 0055 which is 5.5 hours ahead
of GMT.
The data records are coded as:
field bytes length comment
----------------- ------- ------ ------------------------------------
station number 1-3 3 exactly 3 digits
station version 4 1 letter from A to Z
station name 6-9 4 Abbreviated if necessary
year 12-15 4
month 16-17 2 numerical value
day 18-19 2
day record count 20 1 either 1 or 2
sea level data 21-80 60 12 sea level values,
hours 00-11 (1); hours 12-23 (2)
For example:
029A Kapingamarangi Fd St Micronesia 1987 01059N 154466E 0000 1 00000R MM
029A Kapi 1987 1 11 1768 1661 1476 1267 1078 956 914 975 1067 1189 1280 1311
029A Kapi 1987 1 12 1250 1097 975 792 671 610 732 884 1006 1341 1585 1737
029A Kapi 1987 1 21 1829 1768 1692 1494 1219 1036 945 914 1006 1097 1158 1280
029A Kapi 1987 1 22 1341 1219 1097 945 792 701 671 762 884 1067 1341 1554
029A Kapi 1987 1 31 1737 1829 1768 1615 1433 1219 1036 945 914 1006 1036 1189
029A Kapi 1987 1 32 1280 1311 1219 1067 1006 823 732 701 792 884 1097 1372
Dan Kelley Dan.Kelley@Dal.Ca
http://ilikai.soest.hawaii.edu/uhslc/htmld/d0275A.html
The file format given above is verbatim from ftp://ilikai.soest.hawaii.edu/rqds/hourly.fmt