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Cosmic rays consist mainly of protons of extremely high energies. They can originate from galactic sources or from the Sun. Cosmic rays are observed indirectly. At the lowest energies able to reach the Earth's surface, this is achieved by a device known as a neutron monitor. When cosmic ray particles enter the Earth's atmosphere they interact with the nuclei of the air molecules to produce secondary radiation. At the lowest accessible energies, this consists of a shower of protons, nuclear fragments and neutrons; whilst at higher energies it is made up of pions (which decay to muons). The neutrons predominate in this secondary radiation because the protons and nuclear fragments, being charged, are more easily attenuated in subsequent travel. The neutron monitor is designed to detect these secondary neutrons. The SWS WDC archives Cosmic Ray data obtained from Kingston in Tasmania, and Mawson in Antarctica. The first Cosmic Ray data file from both Mawson and Kingston is for June 2004. Kingston station closed at the end of 2016. Data frequency: Daily file; less

Ionospheric scintillation is a rapid fluctuation of radio-frequency signal phase and/or amplitude, which is generated as a signal passes through the ionosphere. Scintillation occurs when a radio frequency signal, in the form of a plane wave, traverses a region of small scale irregularities in electron density. The irregularities cause small-scale fluctuations in refractive index and subsequent differential diffraction (scattering) of the plane wave, producing phase variations along the phase front of the signal. As the signal propagation continues, after passing through the region of irregularities, phase and amplitude scintillation develops through interference of multiple scattered signals. The first Ionospheric Scintillation Monitor in Vanimo was installed in 20/08/1999. Data frequency: Daily file; less

The magnetometer data provides a measure of variations of the Earth's magnetic field in 2 or 3 orthogonal directions, typically in the geomagnetic north-south and east-west directions, as well as vertically. Space Weather Services archives the digital magnetometer data recorded from a number of field installations, some of which are collaborative installations with other organizations. The first available Magnetometer data was recorded at Learmonth, WA, Australia : a site jointly managed by SWS (former IPS) and ICSWSE from the 1st of March 1995. The SWS website provides magetometer data recorded from 14 magnetometers at 12 stations. Partners include ICSWSE, AAD (Australian Antarctic Division), and UoN (Uni of Newcastle). SWS also archives some magnetometer data recorded by GA (GeoScience Australia); however, the GA Magnetometer data is only available on the SWS WDC Intranet. Data frequency: Daily file; less

Ionograms are an image of frequency versus time delay (virtual height) of HF echoes from the ionosphere recorded by an ionosonde. An ionosonde is a swept frequency HF pulsed radar used to monitor the ionosphere. SWS WDC has archived ionogram data from 30 stations, 16 of them are still active at present. The most active ionosondes in Space Weather Network (SWN) are IPS 5D ionosonde. The 5D vertical sounding ionosondes normally sweep in frequency from about 1 to 21.5 MHz. Frequency step resolution for the 5D is 5kHz, with up to 4095 steps available. The step interval is variable, becoming more coarse at higher frequencies as ionograms are generally displayed on a logarithmic scale. Every five minutes, a Ionogram data file is recorded, cleaned and the cleaned ionogram is transfered to SWS Sydney head office for autoscaling and further analysis. The raw ionogram file is recorded in a DVD monthly, which will be posted to Sydney SWS head office every month. SWN also operates a few other digital ionosondes, they are IPS 4D in SCott Base, Antarctic, Canadian Advanced Digital Ionosonde (CADI) in Casey, Macquarie Island and Mawson, Lowell digisonde in Davis station. In the past, the former IPS also used IPS 4c, 4d, 5a and 5c ionosondes. SWS WDC archives all raw digital ionogram files and cleaned ionogram files. The clean ionogram data is available since 1991, and digital raw ionogram data since 1992. The scaled hourly ionospheric data include parameters of foF2, foF1, FoE, foEs, fbEs, fmin, fxl, f'scaling F/s, M(3000)F2, h'F2, h'F, h'E, h'Es, h'Scaling R/S and Type Es. They are avalable since 1938. The median data of foF2 and M(3000)F2 are also available since 1938. Data frequency: every 5 minutes file; less

The SWS WDC ( World Data Centre ) archives Riometer data obtained from Casey, Davis, Mawson and Macquarie Island in Antarctica. The first Riometer data file was obtained on 11/09/1987 from Macquarie Island . Precise start dates per station (as well as the decimal degrees and Glat/Glong) are available from: [ http://www.sws.bom.gov.au/World_Data_Centre/2/4 ]. A riometer (relative ionospheric opacity meter) (30 MHz) is an instrument used to quantify the amount of electromagnetic wave ionospheric absorption in the atmosphere.[1] As the name implies, a riometer measures the "opacity" of the ionosphere to radio noise emanating from distant stars and galaxies. In the absence of any ionospheric absorption, this radio noise, averaged over a sufficiently long period of time, forms a quiet-day curve. Increased ionization in the ionosphere will cause absorption of radio signals (both terrestrial and extraterrestrial), and a departure from the quiet-day curve. The difference between the quiet-day curve and the riometer signal is an indicator of the amount of absorption, and is measured in decibels. Riometers are generally passive radio antenna operating in the VHF radio frequency range (~30 MHz). Previously the cosmic radio noise was typically measured at around 20-50 MHz with wide-beam antennas. Lately, however, a new generation of imaging riometers has appeared. They consist of an array (8 x 8 or so) of wire dipoles forming narrow antenna beams which cover, in total, an area of 100 km x 100 km or more at 90 km altitude. See Detrick and Rosenber (1990) for more discussion on riometer techniques. Data frequency :Daily file; less

Australia has made major contributions to research in solar physics for several decades. Solar images are a major kind of record of solar activities. The SWS has monitored and archived solar activity images from Culgoora and Learmonth for more than two decades. Images from Culgoora include H-Alpha (2003-2014) and White Light(2004-2013) images. A new single mounted, three telescopes structure has been installed at Culgoora. Culgoora solar image data is available for 02/01/2003 onwards. Learmonth Solar Observatory is jointly operated by Bureau of Meteorology - Space Weather Network and the US Air Force. The Learmonth observatory is the site of one of six solar velocity imagers in the world-wide GONG (Global Oscillation Network Group) network operated by NSO (US National Solar Observatory). Images from Learmonth include H-Alpha(2004-2009), GONG H-Alpha (since 2013), GONG White Light(since 2010)and GONG Magnetogram(since 2010) images. Learmonth solar image data is available for 31/05/2004 onwards. Data frequency: Every 60 seconds; less

The discrete frequencies Solar Radio data, also known as Radio Interference Monitoring Sets (RIMS), is obtained from Learmonth Solar Observatory, Western Australia. Equipment: A radio telescope with three parabolic dish antennae to monitor solar radio flux on 8 discrete frequencies in the range 245-15400 MHz. The three parabolic dish antennae feed eight, single frequency, radio telescopes. The largest antenna - 28 feet (8.5 meters) in diameter, is used to monitor 245, 410 and 610 MHz. An 8 feet (2.4 meters) dish is used to monitor the microwave frequencies of 1415, 2695, 4995 and 8800 MHz. A small 3 feet (1 meter) dish monitors the high microwave frequency of 15400 MHz. Radio telescope outputs are digitised (1 Hz sampling rate), collected by computer and transferred to Sydney SWS head Office WDC for processing and archiving. Observers in Learmonth also send DVDs with RIMS (2 DVD per year) to SWS as backup for the ftp data. To date, four different formats of RIMS data have been archived : SRD (from 2005), APL(1999-2008), LSR(1991-2006) and rdata(2003-2005). All of the above formats are available on the SWS FTP server and SWS website. All of the data files are online, plottable, and downloadable. Data frequency: Daily file; less

Culgoora and Learmonth Observatories' dynamic spectrogram plots display frequency in MHz on the vertical axis and time in UT on the horizontal axis. Each plot spans local daylight hours, with time resolution of 3 seconds. The frequency range is 18 - 1800 MHz for Culgoora spectrograms, and 25 - 180 MHz for Learmonth spectrograms. The intensity values are color coded, and are expressed as relative logarithmic units (0 to 255). The Culgoora spectrograms consist of 4 frequency bands: 18-57, 57-180, 180-570 570 -1800 MHz; and Learmonth has 2 bands: 25-75, 75-180 MHz. The two Learmonth bands are each divided into 400 frequency steps. Culgoora spectrograph data is available for November 1992 onwards, Learmonth data for June 2000 onwards. Data frequency :Daily file; less

The SWS sunspot number tables are based on the observed (definitive and provisional) monthly mean sunspot numbers from WDC-SILSO, Royal Observatory of Belgium, Brussels (sidc.oma.be/silso/home). The observed values are smoothed using a 13 month running filter (the first and last values have half weighting). Estimated values have an "e" suffix and are calculated from observed monthly and predicted smoothed sunspot numbers. Observed smoothed values precede the estimated values, while predicted smoothed values follow the estimated values. The 10.7 cm solar radio flux values, including the "observed" values, are obtained from sunspot numbers using a statistical conversion. They are therefore described as "equivalent" solar radio flux values. SPECIAL NOTE In June 2015, WDC-SILSO, Royal Observatory of Belgium, Brussels, adjusted their original observed sunspot numbers (Version 1.0) to a Version 2.0 series in which the sunspot numbers are higher. In the Version 1.0 data series, some of the sunspot numbers were weighted. The new (Version 2.0) sunspot numbers are unweighted sunspot number counts (for more information see: www.sidc.be/silso/home). The Bureau of Meteorology SWS solar cycle prediction is now based on the Version 2.0 values. As a result of the WDC-SILSO recalibration, the observed monthly sunspot numbers are higher. This is also reflected in the tables of smoothed sunspot numbers and equivalent 10.7 cm solar flux and the solar cycle graph. Data frequency :Daily figure; less