2008-08
AUTHORSDavid H. Hathaway, Debi Prasad Choudhary
ABSTRACTWe examine daily records of sunspot group areas (measured in millionths of a solar hemisphere or μHem) for the last 130 years to determine the rate of decay of sunspot group areas. We exclude observations of groups when they are more than 60° in longitude from the central meridian and only include data when at least three days of observations are available following the date of maximum area for a group’s disk passage. This leaves data for over 18 000 measurements of sunspot group decay. We find that the decay rate increases linearly from 28 μHem day−1 to about 140 μHem day−1 for groups with areas increasing from 35 μHem to 1000 μHem. The decay rate tends to level off for groups with areas larger than 1000 μHem. This behavior is very similar to the increase in the number of sunspots per group as the area of the group increases. Calculating the decay rate per individual sunspot gives a decay rate of about 3.65 μHem day−1 with little dependence upon the area of the group. This suggests that sunspots decay by a Fickian diffusion process with a diffusion coefficient of about 10 km2 s−1. Although the 18 000 decay rate measurements are lognormally distributed, this can be attributed to the lognormal distribution of sunspot group areas and the linear relationship between area and decay rate for the vast majority of groups. We find weak evidence for variations in decay rates from one solar cycle to another and for different phases of each sunspot cycle. However, the strongest evidence for variations is with latitude and the variations with cycle and phase of each cycle can be attributed to this variation. High latitude spots tend to decay faster than low latitude spots. More... »
PAGES269-278
http://scigraph.springernature.com/pub.10.1007/s11207-008-9226-4
DOIhttp://dx.doi.org/10.1007/s11207-008-9226-4
DIMENSIONShttps://app.dimensions.ai/details/publication/pub.1040979906
JSON-LD is the canonical representation for SciGraph data.
TIP: You can open this SciGraph record using an external JSON-LD service: JSON-LD Playground Google SDTT
[
{
"@context": "https://springernature.github.io/scigraph/jsonld/sgcontext.json",
"about": [
{
"id": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/0101",
"inDefinedTermSet": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/",
"name": "Pure Mathematics",
"type": "DefinedTerm"
},
{
"id": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/01",
"inDefinedTermSet": "http://purl.org/au-research/vocabulary/anzsrc-for/2008/",
"name": "Mathematical Sciences",
"type": "DefinedTerm"
}
],
"author": [
{
"affiliation": {
"alternateName": "National Space Science and Technology Center",
"id": "https://www.grid.ac/institutes/grid.462618.f",
"name": [
"NSSTC/NASA/Marshall Space Flight Center, 35812, Huntsville, AL, USA"
],
"type": "Organization"
},
"familyName": "Hathaway",
"givenName": "David H.",
"id": "sg:person.015671020013.55",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.015671020013.55"
],
"type": "Person"
},
{
"affiliation": {
"alternateName": "California State University, Northridge",
"id": "https://www.grid.ac/institutes/grid.253563.4",
"name": [
"San Fernando Observatory, Department of Physics and Astronomy, California State University Northridge, 18111 Nordhoff Street, Northridge, CA, USA"
],
"type": "Organization"
},
"familyName": "Choudhary",
"givenName": "Debi Prasad",
"id": "sg:person.015537154045.70",
"sameAs": [
"https://app.dimensions.ai/discover/publication?and_facet_researcher=ur.015537154045.70"
],
"type": "Person"
}
],
"citation": [
{
"id": "sg:pub.10.1023/a:1022425402664",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1000734952",
"https://doi.org/10.1023/a:1022425402664"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1002/1521-3994(200208)323:3/4<178::aid-asna178>3.0.co;2-e",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1000854411"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00162376",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1008226347",
"https://doi.org/10.1007/bf00162376"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00680629",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1012536124",
"https://doi.org/10.1007/bf00680629"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00680629",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1012536124",
"https://doi.org/10.1007/bf00680629"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1002/1521-3994(200208)323:3/4<342::aid-asna342>3.0.co;2-5",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1014024052"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00153288",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1019394665",
"https://doi.org/10.1007/bf00153288"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00153288",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1019394665",
"https://doi.org/10.1007/bf00153288"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00156633",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1022875731",
"https://doi.org/10.1007/bf00156633"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00156633",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1022875731",
"https://doi.org/10.1007/bf00156633"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1023/a:1004988123265",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1023389424",
"https://doi.org/10.1023/a:1004988123265"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1093/mnras/179.4.741",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1028572917"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00146575",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1029532021",
"https://doi.org/10.1007/bf00146575"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00146575",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1029532021",
"https://doi.org/10.1007/bf00146575"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00157230",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1033322603",
"https://doi.org/10.1007/bf00157230"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00157230",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1033322603",
"https://doi.org/10.1007/bf00157230"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1023/a:1004971807172",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1035672349",
"https://doi.org/10.1023/a:1004971807172"
],
"type": "CreativeWork"
},
{
"id": "sg:pub.10.1007/bf00652636",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1039308242",
"https://doi.org/10.1007/bf00652636"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1029/2002gl016225",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1043702214"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1093/mnras/106.3.218",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1049048896"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1086/318333",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1053168308"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1051/0004-6361:20010429",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1056926905"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1086/166206",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1058497496"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1086/172370",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1058503660"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1086/174967",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1058506257"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1086/344196",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1058640367"
],
"type": "CreativeWork"
},
{
"id": "https://doi.org/10.1126/science.211.4483.700",
"sameAs": [
"https://app.dimensions.ai/details/publication/pub.1062522576"
],
"type": "CreativeWork"
}
],
"datePublished": "2008-08",
"datePublishedReg": "2008-08-01",
"description": "We examine daily records of sunspot group areas (measured in millionths of a solar hemisphere or \u03bcHem) for the last 130 years to determine the rate of decay of sunspot group areas. We exclude observations of groups when they are more than 60\u00b0 in longitude from the central meridian and only include data when at least three days of observations are available following the date of maximum area for a group\u2019s disk passage. This leaves data for over 18 000 measurements of sunspot group decay. We find that the decay rate increases linearly from 28 \u03bcHem day\u22121 to about 140 \u03bcHem day\u22121 for groups with areas increasing from 35 \u03bcHem to 1000 \u03bcHem. The decay rate tends to level off for groups with areas larger than 1000 \u03bcHem. This behavior is very similar to the increase in the number of sunspots per group as the area of the group increases. Calculating the decay rate per individual sunspot gives a decay rate of about 3.65 \u03bcHem day\u22121 with little dependence upon the area of the group. This suggests that sunspots decay by a Fickian diffusion process with a diffusion coefficient of about 10 km2 s\u22121. Although the 18 000 decay rate measurements are lognormally distributed, this can be attributed to the lognormal distribution of sunspot group areas and the linear relationship between area and decay rate for the vast majority of groups. We find weak evidence for variations in decay rates from one solar cycle to another and for different phases of each sunspot cycle. However, the strongest evidence for variations is with latitude and the variations with cycle and phase of each cycle can be attributed to this variation. High latitude spots tend to decay faster than low latitude spots.",
"genre": "research_article",
"id": "sg:pub.10.1007/s11207-008-9226-4",
"inLanguage": [
"en"
],
"isAccessibleForFree": false,
"isPartOf": [
{
"id": "sg:journal.1051932",
"issn": [
"0038-0938",
"1573-093X"
],
"name": "Solar Physics",
"type": "Periodical"
},
{
"issueNumber": "2",
"type": "PublicationIssue"
},
{
"type": "PublicationVolume",
"volumeNumber": "250"
}
],
"name": "Sunspot Group Decay",
"pagination": "269-278",
"productId": [
{
"name": "readcube_id",
"type": "PropertyValue",
"value": [
"c337271c80088a51214f0df1ac170547355bd98d334b94a94b45dd8da56588de"
]
},
{
"name": "doi",
"type": "PropertyValue",
"value": [
"10.1007/s11207-008-9226-4"
]
},
{
"name": "dimensions_id",
"type": "PropertyValue",
"value": [
"pub.1040979906"
]
}
],
"sameAs": [
"https://doi.org/10.1007/s11207-008-9226-4",
"https://app.dimensions.ai/details/publication/pub.1040979906"
],
"sdDataset": "articles",
"sdDatePublished": "2019-04-10T23:27",
"sdLicense": "https://scigraph.springernature.com/explorer/license/",
"sdPublisher": {
"name": "Springer Nature - SN SciGraph project",
"type": "Organization"
},
"sdSource": "s3://com-uberresearch-data-dimensions-target-20181106-alternative/cleanup/v134/2549eaecd7973599484d7c17b260dba0a4ecb94b/merge/v9/a6c9fde33151104705d4d7ff012ea9563521a3ce/jats-lookup/v90/0000000001_0000000264/records_8693_00000523.jsonl",
"type": "ScholarlyArticle",
"url": "http://link.springer.com/10.1007%2Fs11207-008-9226-4"
}
]Download the RDF metadata as: json-ld nt turtle xml License info
JSON-LD is a popular format for linked data which is fully compatible with JSON.
curl -H 'Accept: application/ld+json' 'https://scigraph.springernature.com/pub.10.1007/s11207-008-9226-4'
N-Triples is a line-based linked data format ideal for batch operations.
curl -H 'Accept: application/n-triples' 'https://scigraph.springernature.com/pub.10.1007/s11207-008-9226-4'
Turtle is a human-readable linked data format.
curl -H 'Accept: text/turtle' 'https://scigraph.springernature.com/pub.10.1007/s11207-008-9226-4'
RDF/XML is a standard XML format for linked data.
curl -H 'Accept: application/rdf+xml' 'https://scigraph.springernature.com/pub.10.1007/s11207-008-9226-4'
This table displays all metadata directly associated to this object as RDF triples.
147 TRIPLES
21 PREDICATES
49 URIs
19 LITERALS
7 BLANK NODES