Solar White Light Faculae Data (All ftp)

Solar White Light Faculae are areas of bright plages on the solar disk. These were routinely measured at the Royal Greenwich Observatory in the UK from 1874 to 1976, producing a record of over 100 years of continuous monitoring of this solar phenomenon. Detailed positions and areas of sunspots and faculae for each day in the year are available. As part of a data rescue effort in 1999, NOAA had these analog records keyed into digital form.

The record includes the time when the photograph was taken, the station observing (includes Greenwich, Cape of Good Hope, Kodaikanal, and Mauritius), a group number, the position of the spot group and/or faculae, the area of the spots, and the faculae area for each group. The dark sunspot group areas block the solar radiation from the Sun. The bright white light faculae enhance the solar radiation from the Sun. Models of the total solar irradiance include both these opposing forces of dark sunspot group areas and the bright white light faculae areas.

These Greenwich data are also available at the NGDC Solar Sunspot Regions web page in a different format. That database was compiled by Fred Ward, USAF AFCRL, in the 1960s and later updated by Doug Hoyt in the 1990s. The Greenwich data books have two sections and the data are somewhat different between the two sets of data.

• Description of the data and format (text)
  • Listings of Daily values by group in annual tables
    • 1874 1875 1876 1877 1878 1879
    • 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889
    • 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899
    • 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909
    • 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919
    • 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929
    • 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939
    • 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949
    • 1950 1951 1952 1953 1954 1955
    
    
  • Footnotes for the related Group Numbers

• Format of the summary data (text) -- with daily projected umbral area and total sunspot area, daily projected faculae area for Eastern hemisphere, daily projected faculae area for the Western hemisphere, corrected umbral and total sunspot area, and corrected faculae areas for the Eastern and Western hemisphere
  • Daily values in annual files
    • 1956 1957 1958 1959
    • 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969
    • 1970 1971 1972 1973 1974 1975 1976

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