<HTML>
  <HEAD><TITLE>Oulu Neutron Monitor Data Base</TITLE></HEAD>
   <BODY BACKGROUND="red">
<h2 align=center>Data base of Oulu Neutron Monitor</h2>

Database contents of Oulu neutron monitor data starting from April 1964:
Hourly since April 1964, 5-min since 1968, 1-minute data since 1996
(9NM-Supermonitor). 
The interval of accumulation: Database updating goes in real
time. An interactive access is possible to this database and FTP
as well. <h3>Interactive access</h3> Data in this regime are
available in graphical and in digital presentation as well. All
graphical plots are given relative to "February 1987".
<h3>Access by FTP</h3>
One-minute data are in directory ftp_NM1, hourly data in
directory ftp_NM. Ground Level Enhancement (GLE) data are in the
GLE directory. One-type data are presented in their own Format:
hourly data in format C, 1-minute data in W format, and GLE data
in GLE format.
<p> There are three types of 1-minute data: neutron
monitor data corrected for atmospheric pressure (C), atmospheric
pressure (P), and neutron monitor data uncorrected for atmospheric
pressure (U).

Hourly data are presented uncorrected
(U) and corrected for atmospheric pressure (P).
Pressure corrected hourly data are kept as original (O)
and corrected (C).
<!-- Corrected data firstly are the same as original data, but they may be
corrected in future e.g. for the snow effect, for the possible
long time jumps, when the sweing is required, slow drift, and, at
last, cleaning data for the occasional mistakes.
The special
programs are closed in the corresponding folders to look through
data in the grafical regime. They should be replaced on your
computer to be used. Thus, to look through 1-minute and hourly
data the program Plot_DAT should be used, and for GLE data use
Plot_GLE program. After the corresponding Folder is  opened by
command OPEN, the following sort should be done: all type ( *.w1u,
*.w1p, *.w1c) - select and plot 1-minute data, all type (*.?0u,
*.?0p, *.?0o, *.?0c) - select and plot hourly data. --> </BODY>
</HTML>