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Daily total and hemispheric sunspot numbers

Time range:
1/1/1992 - last elapsed month (provisional values): daily total and hemispheric sunspot numbers

Data description:
Daily total and hemispheric sunspot numbers derived by the formula: R= Ns + 10 * Ng, with Ns the number of spots and Ng the number of groups counted either over the entire solar disk (total), the North hemisphere or South hemisphere (based on the sunspot group heliographic latitude).

The North and South numbers are always normalized to the total number, which is the global scaling reference. The production of the hemispheric numbers together with the international total Sunspot Number started only in 1992.

New scale:
The conventional 0.6 Zürich scale factor is not used anymore and A. Wolfer (Wolf's successor) is now defining the scale of the entire series. This puts the Sunspot Number at the scale of raw modern counts, instead of reducing it to the level of early counts by R. Wolf.

Error values:
Those values correspond to the standard deviation of raw numbers provided by all stations. The error value for the total number is the actual standard deviation of the sample of raw observations used to compute the daily value.
As the actual standard deviations of raw daily hemispheric counts were not archived in the past, we derive an estimate of these standard deviations with the help of the same auto-regressive model based on the Poissonian distribution of actual Sunspot Numbers.

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TXT : all years from 1992 to last elapsed month
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Filename: SN_d_hem_V2.0.txt

Format: plain ASCII text

Contents:
Columns 1-3: Gregorian calendar date
Column 1: Year
Column 2: Month
Column 3: Day
Column 4: Date in fraction of year
Column 5: Daily total sunspot number.
Column 6: Daily North sunspot number.
Column 7: Daily South sunspot number.
Column 8: Standard deviation of raw daily total sunspot data
Column 9: Standard deviation of raw daily North sunspot data
Column 10: Standard deviation of raw daily South sunspot data
Column 11: Number of observations in daily total sunspot number
Column 12: Number of observations in daily North sunspot number (not determined yet: -1)
Column 13: Number of observations in daily South sunspot number (not determined yet: -1)
Column 14: Definitive/provisional marker. A blank indicates that the value is definitive. A '*' symbol indicates that the value is still provisional and is subject to a possible revision (Usually the last 3 to 6 months)

Line format [character position]:
- [1-4] Year
- [6-7] Month
- [9-10] Day
- [12-19] Decimal date
- [22-24] Daily total sunspot number
- [26-28] Daily north sunspot number
- [30-32] Daily south sunspot number
- [35-39] Standard deviation (Total)
- [41-45] Standard deviation (North)
- [46-51] Standard deviation (South)
- [54-56] Number of observations (Total)
- [58-60] Number of observations (North)
- [62-64] Number of observations (South)
- [66] Definitive/provisional indicator
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CSV : all years from 1/1/1992 to last elapsed month
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Filename: SN_d_hem_V2.0.csv
Format: Comma Separated values (adapted for import in spreadsheets)
The separator is the semicolon ';'.

Contents:
Columns 1-3: Gregorian calendar date
Column 1: Year
Column 2: Month
Column 3: Day
Column 4: Date in fraction of year
Column 5: Daily total sunspot number.
Column 6: Daily North sunspot number.
Column 7: Daily South sunspot number.
Column 8: Standard deviation of raw daily total sunspot data
Column 9: Standard deviation of raw daily North sunspot data
Column 10: Standard deviation of raw daily South sunspot data
Column 11: Number of observations in daily total sunspot number
Column 12: Number of observations in daily North sunspot number (not determined yet: -1)
Column 13: Number of observations in daily South sunspot number (not determined yet: -1)
Column 14: Definitive/provisional marker. '1' indicates that the value is definitive. '0' indicates that the value is still provisional and is subject to a possible revision (Usually the last 3 to 6 months)
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LICENSE
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