Solar Radio DataAlternate Views: Get Data, FAQ, ISO Rubric, DOI Rubric, CSW, HTML, Components, XML
Solar Radio Data
Scientists monitor the structure of the solar corona, the outer most regions of the Sun’s atmosphere, using radio waves. The surface of the Sun is 6,000 degrees Kelvin, while the high corona can reach several million degrees Kelvin. Solar radio emissions at different frequencies allow us to observe radiation from different heights in the atmosphere. The lower the frequency, the higher the height of origin. The frequency, like the electron density, decreases uniformly outwards: 245 MHz originates high in the corona, while 15,400 MHz originates in the low corona. The 5 MHz emission corresponds to about 10 solar radii height. For a detailed review, see McLean and Labrum (1985)Solar Radiophysics.Radio bursts are associated with solar flares. The delay at Earth of the different radio frequencies during burst events is due to the outward movement of the source. Bursts can have temperatures of 10xE12 degrees Kelvin. Large bursts last 10 to 20 minutes on average. Longer radio noise storms of persistent and variable high levels of radiation originate in sunspot groups, areas of large, intense magnetic fields. These storms are strongly circularly polarized due to the intense magnetic fields.The microwave wavelength 2800 MHz daily radio flux correlates highly with the daily sunspot number and the two databases are used interchangeably. The 2800 MHz, or 10.7 cm, responds to the same conditions that produce changes in the visible and X-ray wavelengths. Schmahl and Kundu (1995) find that the solar radio fluxes in the spectral range 1000-9400 MHz correlate well with the total solar irradiance. The intermediate frequencies (at 2800 and 3750 MHz) are produced mainly by free-free gyroresonance emission from sunspot structures, while 1000 and 9400 MHz flux are produced mainly by free-free processes from structures associated with plages. They can distinguish plage-associated emission from spot-associated emission in the time series of microwave flux, both contributing opposing effects on the total solar irradiance.

Get the Data
AccessFormat(s)Distributor(s) / Contact InfoInstructions / Constraints
http://www.ngdc.noaa.gov/stp/SOLAR/ftpsolarradio.html
ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_RADIO
http://www.ngdc.noaa.gov/stp/SOLAR/ftpsolarradio.html
ftp://ftp.ngdc.noaa.gov/STP/SOLAR_DATA/SOLAR_RADIO
ASCII
Format version: (version is unknown)
Solar Data Manager
DOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce
Contact Data Center
303.497.6133 or 303.497.6323
7:30 - 4:30 Mountain
Fees
$100.00/$75.00 plus handling and shipping outside the USA

Ordering Instructions
Ordering Instructions: Product may be ordered directly from our online store via: http://ols.nndc.noaa.gov/plolstore/plsql/olstore.prodspecific?prodnum=G01254-CDR-A0001 Custom Order Process: Contact data center for information

Legal Constraints
Access
otherRestrictions

Use Limitation
otherRestrictions

Other
Access Constraints: No Constraints Use Constraints: None Distribution Liability: While every effort has been made to ensure that these data are accurate and reliable within the limits of the current state of the art, NOAA cannot assume liability for any damages caused by any errors or omissions in the data.