A Test of the Active-Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity
The method of active-day fraction (ADF) was proposed recently to calibrate different solar observers to standard observational conditions. The result of the calibration may depend on the overall level of solar activity during the observational period. This dependency is studied quantitatively using...
Gespeichert in:
| Veröffentlicht in: | Solar physics 2018-04, Vol.293 (4), p.1-6, Article 69 |
|---|---|
| Hauptverfasser: | , , |
| Format: | Artikel |
| Sprache: | eng |
| Schlagworte: | |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | 6 |
|---|---|
| container_issue | 4 |
| container_start_page | 1 |
| container_title | Solar physics |
| container_volume | 293 |
| creator | Willamo, T. Usoskin, I. G. Kovaltsov, G. A. |
| description | The method of active-day fraction (ADF) was proposed recently to calibrate different solar observers to standard observational conditions. The result of the calibration may depend on the overall level of solar activity during the observational period. This dependency is studied quantitatively using data of the Royal Greenwich Observatory by formally calibrating synthetic pseudo-observers to the full reference dataset. It is shown that the sunspot group number is precisely estimated by the ADF method for periods of moderate activity, may be slightly underestimated by 0.5 – 1.5 groups (
≤
10
%
) for strong and very strong activity, and is strongly overestimated by up to 2.5 groups (
≤
30
%
) for weak-to-moderate activity. The ADF method becomes inapplicable for the periods of grand minima of activity. In general, the ADF method tends to overestimate the overall level of activity and to reduce the long-term trends. |
| doi_str_mv | 10.1007/s11207-018-1292-7 |
| format | Article |
| fullrecord | <record><control><sourceid>proquest_cross</sourceid><recordid>TN_cdi_proquest_journals_2024342162</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>2024342162</sourcerecordid><originalsourceid>FETCH-LOGICAL-c382t-a4ac2fe48be0f82048abbc48a64c8ce6e0756c1e5eafd08a6c287f16ea1466503</originalsourceid><addsrcrecordid>eNp1kM1OwzAQhC0EEqXwANwscTasnT-XW1VoQSpwoEjcLMfd0FRpHOykqG-PQ5A4cVnvWvPNaoeQSw7XHCC78ZwLyBhwybiYCJYdkRFPsojBJHo_JiOASPa9PCVn3m8BeioZka8pXaFvqS1ou0E6NW25R3anD3TudBhsTZ-w3dh1r3jtat_Yli6c7Rr63O1ydHSmqzJ3upfe0jtssF5jbZAGsndc4h6rH9hW2g0LyvZwTk4KXXm8-H3H5G1-v5o9sOXL4nE2XTITSdEyHWsjCoxljlBIAbHUeW5CTWMjDaYYjkgNxwR1sYbwbYTMCp6i5nGaJhCNydXg2zj72YVL1dZ2rg4rlQARR7HgqQgqPqiMs947LFTjyp12B8VB9UmpIV8V8lV9vioLjBgYH7T1B7o_5_-hb8_PfcA</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>2024342162</pqid></control><display><type>article</type><title>A Test of the Active-Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity</title><source>SpringerLink Journals - AutoHoldings</source><creator>Willamo, T. ; Usoskin, I. G. ; Kovaltsov, G. A.</creator><creatorcontrib>Willamo, T. ; Usoskin, I. G. ; Kovaltsov, G. A.</creatorcontrib><description>The method of active-day fraction (ADF) was proposed recently to calibrate different solar observers to standard observational conditions. The result of the calibration may depend on the overall level of solar activity during the observational period. This dependency is studied quantitatively using data of the Royal Greenwich Observatory by formally calibrating synthetic pseudo-observers to the full reference dataset. It is shown that the sunspot group number is precisely estimated by the ADF method for periods of moderate activity, may be slightly underestimated by 0.5 – 1.5 groups (
≤
10
%
) for strong and very strong activity, and is strongly overestimated by up to 2.5 groups (
≤
30
%
) for weak-to-moderate activity. The ADF method becomes inapplicable for the periods of grand minima of activity. In general, the ADF method tends to overestimate the overall level of activity and to reduce the long-term trends.</description><identifier>ISSN: 0038-0938</identifier><identifier>EISSN: 1573-093X</identifier><identifier>DOI: 10.1007/s11207-018-1292-7</identifier><language>eng</language><publisher>Dordrecht: Springer Netherlands</publisher><subject>Astrophysics and Astroparticles ; Atmospheric Sciences ; Calibration ; Observers ; Physics ; Physics and Astronomy ; Solar activity ; Solar physics ; Space Exploration and Astronautics ; Space Sciences (including Extraterrestrial Physics ; Sunspots</subject><ispartof>Solar physics, 2018-04, Vol.293 (4), p.1-6, Article 69</ispartof><rights>Springer Science+Business Media B.V., part of Springer Nature 2018</rights><rights>Solar Physics is a copyright of Springer, (2018). All Rights Reserved.</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c382t-a4ac2fe48be0f82048abbc48a64c8ce6e0756c1e5eafd08a6c287f16ea1466503</citedby><cites>FETCH-LOGICAL-c382t-a4ac2fe48be0f82048abbc48a64c8ce6e0756c1e5eafd08a6c287f16ea1466503</cites><orcidid>0000-0001-8227-9081</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://link.springer.com/content/pdf/10.1007/s11207-018-1292-7$$EPDF$$P50$$Gspringer$$H</linktopdf><linktohtml>$$Uhttps://link.springer.com/10.1007/s11207-018-1292-7$$EHTML$$P50$$Gspringer$$H</linktohtml><link.rule.ids>314,777,781,27905,27906,41469,42538,51300</link.rule.ids></links><search><creatorcontrib>Willamo, T.</creatorcontrib><creatorcontrib>Usoskin, I. G.</creatorcontrib><creatorcontrib>Kovaltsov, G. A.</creatorcontrib><title>A Test of the Active-Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity</title><title>Solar physics</title><addtitle>Sol Phys</addtitle><description>The method of active-day fraction (ADF) was proposed recently to calibrate different solar observers to standard observational conditions. The result of the calibration may depend on the overall level of solar activity during the observational period. This dependency is studied quantitatively using data of the Royal Greenwich Observatory by formally calibrating synthetic pseudo-observers to the full reference dataset. It is shown that the sunspot group number is precisely estimated by the ADF method for periods of moderate activity, may be slightly underestimated by 0.5 – 1.5 groups (
≤
10
%
) for strong and very strong activity, and is strongly overestimated by up to 2.5 groups (
≤
30
%
) for weak-to-moderate activity. The ADF method becomes inapplicable for the periods of grand minima of activity. In general, the ADF method tends to overestimate the overall level of activity and to reduce the long-term trends.</description><subject>Astrophysics and Astroparticles</subject><subject>Atmospheric Sciences</subject><subject>Calibration</subject><subject>Observers</subject><subject>Physics</subject><subject>Physics and Astronomy</subject><subject>Solar activity</subject><subject>Solar physics</subject><subject>Space Exploration and Astronautics</subject><subject>Space Sciences (including Extraterrestrial Physics</subject><subject>Sunspots</subject><issn>0038-0938</issn><issn>1573-093X</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2018</creationdate><recordtype>article</recordtype><sourceid>ABUWG</sourceid><sourceid>AFKRA</sourceid><sourceid>AZQEC</sourceid><sourceid>BENPR</sourceid><sourceid>CCPQU</sourceid><sourceid>DWQXO</sourceid><sourceid>GNUQQ</sourceid><recordid>eNp1kM1OwzAQhC0EEqXwANwscTasnT-XW1VoQSpwoEjcLMfd0FRpHOykqG-PQ5A4cVnvWvPNaoeQSw7XHCC78ZwLyBhwybiYCJYdkRFPsojBJHo_JiOASPa9PCVn3m8BeioZka8pXaFvqS1ou0E6NW25R3anD3TudBhsTZ-w3dh1r3jtat_Yli6c7Rr63O1ydHSmqzJ3upfe0jtssF5jbZAGsndc4h6rH9hW2g0LyvZwTk4KXXm8-H3H5G1-v5o9sOXL4nE2XTITSdEyHWsjCoxljlBIAbHUeW5CTWMjDaYYjkgNxwR1sYbwbYTMCp6i5nGaJhCNydXg2zj72YVL1dZ2rg4rlQARR7HgqQgqPqiMs947LFTjyp12B8VB9UmpIV8V8lV9vioLjBgYH7T1B7o_5_-hb8_PfcA</recordid><startdate>20180401</startdate><enddate>20180401</enddate><creator>Willamo, T.</creator><creator>Usoskin, I. G.</creator><creator>Kovaltsov, G. A.</creator><general>Springer Netherlands</general><general>Springer Nature B.V</general><scope>AAYXX</scope><scope>CITATION</scope><scope>3V.</scope><scope>7TG</scope><scope>7XB</scope><scope>88I</scope><scope>8FD</scope><scope>8FE</scope><scope>8FG</scope><scope>8FK</scope><scope>ABUWG</scope><scope>AEUYN</scope><scope>AFKRA</scope><scope>ARAPS</scope><scope>AZQEC</scope><scope>BENPR</scope><scope>BGLVJ</scope><scope>CCPQU</scope><scope>DWQXO</scope><scope>GNUQQ</scope><scope>H8D</scope><scope>HCIFZ</scope><scope>KL.</scope><scope>L7M</scope><scope>M2P</scope><scope>P5Z</scope><scope>P62</scope><scope>PQEST</scope><scope>PQQKQ</scope><scope>PQUKI</scope><scope>Q9U</scope><orcidid>https://orcid.org/0000-0001-8227-9081</orcidid></search><sort><creationdate>20180401</creationdate><title>A Test of the Active-Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity</title><author>Willamo, T. ; Usoskin, I. G. ; Kovaltsov, G. A.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c382t-a4ac2fe48be0f82048abbc48a64c8ce6e0756c1e5eafd08a6c287f16ea1466503</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2018</creationdate><topic>Astrophysics and Astroparticles</topic><topic>Atmospheric Sciences</topic><topic>Calibration</topic><topic>Observers</topic><topic>Physics</topic><topic>Physics and Astronomy</topic><topic>Solar activity</topic><topic>Solar physics</topic><topic>Space Exploration and Astronautics</topic><topic>Space Sciences (including Extraterrestrial Physics</topic><topic>Sunspots</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Willamo, T.</creatorcontrib><creatorcontrib>Usoskin, I. G.</creatorcontrib><creatorcontrib>Kovaltsov, G. A.</creatorcontrib><collection>CrossRef</collection><collection>ProQuest Central (Corporate)</collection><collection>Meteorological & Geoastrophysical Abstracts</collection><collection>ProQuest Central (purchase pre-March 2016)</collection><collection>Science Database (Alumni Edition)</collection><collection>Technology Research Database</collection><collection>ProQuest SciTech Collection</collection><collection>ProQuest Technology Collection</collection><collection>ProQuest Central (Alumni) (purchase pre-March 2016)</collection><collection>ProQuest Central (Alumni Edition)</collection><collection>ProQuest One Sustainability</collection><collection>ProQuest Central UK/Ireland</collection><collection>Advanced Technologies & Aerospace Collection</collection><collection>ProQuest Central Essentials</collection><collection>ProQuest Central</collection><collection>Technology Collection</collection><collection>ProQuest One Community College</collection><collection>ProQuest Central Korea</collection><collection>ProQuest Central Student</collection><collection>Aerospace Database</collection><collection>SciTech Premium Collection</collection><collection>Meteorological & Geoastrophysical Abstracts - Academic</collection><collection>Advanced Technologies Database with Aerospace</collection><collection>Science Database</collection><collection>Advanced Technologies & Aerospace Database</collection><collection>ProQuest Advanced Technologies & Aerospace Collection</collection><collection>ProQuest One Academic Eastern Edition (DO NOT USE)</collection><collection>ProQuest One Academic</collection><collection>ProQuest One Academic UKI Edition</collection><collection>ProQuest Central Basic</collection><jtitle>Solar physics</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Willamo, T.</au><au>Usoskin, I. G.</au><au>Kovaltsov, G. A.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>A Test of the Active-Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity</atitle><jtitle>Solar physics</jtitle><stitle>Sol Phys</stitle><date>2018-04-01</date><risdate>2018</risdate><volume>293</volume><issue>4</issue><spage>1</spage><epage>6</epage><pages>1-6</pages><artnum>69</artnum><issn>0038-0938</issn><eissn>1573-093X</eissn><abstract>The method of active-day fraction (ADF) was proposed recently to calibrate different solar observers to standard observational conditions. The result of the calibration may depend on the overall level of solar activity during the observational period. This dependency is studied quantitatively using data of the Royal Greenwich Observatory by formally calibrating synthetic pseudo-observers to the full reference dataset. It is shown that the sunspot group number is precisely estimated by the ADF method for periods of moderate activity, may be slightly underestimated by 0.5 – 1.5 groups (
≤
10
%
) for strong and very strong activity, and is strongly overestimated by up to 2.5 groups (
≤
30
%
) for weak-to-moderate activity. The ADF method becomes inapplicable for the periods of grand minima of activity. In general, the ADF method tends to overestimate the overall level of activity and to reduce the long-term trends.</abstract><cop>Dordrecht</cop><pub>Springer Netherlands</pub><doi>10.1007/s11207-018-1292-7</doi><tpages>6</tpages><orcidid>https://orcid.org/0000-0001-8227-9081</orcidid></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0038-0938 |
| ispartof | Solar physics, 2018-04, Vol.293 (4), p.1-6, Article 69 |
| issn | 0038-0938 1573-093X |
| language | eng |
| recordid | cdi_proquest_journals_2024342162 |
| source | SpringerLink Journals - AutoHoldings |
| subjects | Astrophysics and Astroparticles Atmospheric Sciences Calibration Observers Physics Physics and Astronomy Solar activity Solar physics Space Exploration and Astronautics Space Sciences (including Extraterrestrial Physics Sunspots |
| title | A Test of the Active-Day Fraction Method of Sunspot Group Number Calibration: Dependence on the Level of Solar Activity |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-01-18T10%3A15%3A21IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_cross&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=A%20Test%20of%20the%20Active-Day%20Fraction%20Method%20of%20Sunspot%20Group%20Number%20Calibration:%20Dependence%20on%20the%20Level%20of%20Solar%20Activity&rft.jtitle=Solar%20physics&rft.au=Willamo,%20T.&rft.date=2018-04-01&rft.volume=293&rft.issue=4&rft.spage=1&rft.epage=6&rft.pages=1-6&rft.artnum=69&rft.issn=0038-0938&rft.eissn=1573-093X&rft_id=info:doi/10.1007/s11207-018-1292-7&rft_dat=%3Cproquest_cross%3E2024342162%3C/proquest_cross%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=2024342162&rft_id=info:pmid/&rfr_iscdi=true |