Low Geo‐Effectiveness of Fast Halo CMEs Related to the 12 X‐Class Flares in 2002

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378289%3A_____%2F20%3A00539532" target="_blank" >RIV/68378289:_____/20:00539532 - isvavai.cz</a>

Výsledek na webu

<a href="http://arxiv.org/pdf/2003.10777" target="_blank" >http://arxiv.org/pdf/2003.10777</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1029/2019JA027529" target="_blank" >10.1029/2019JA027529</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Low Geo‐Effectiveness of Fast Halo CMEs Related to the 12 X‐Class Flares in 2002

Popis výsledku v původním jazyce

It is generally accepted that extreme space weather events tend to be related to strong flares and fast halo coronal mass ejections (CMEs). In the present paper, we carefully identify the chain of events from the Sun to the Earth induced by all 12 X‐class flares that occurred in 2002. In this small sample, we find an unusual high rate (58%) of solar sources with a longitude larger than 74°. Yet all 12 X‐class flares are associated with at least one CME. The fast halo CMEs (50%) are related to interplanetary CMEs (ICMEs) at L1 and weak Dst minimum values (more than −51 nT), while five (41%) of the 12 X‐class flares are related to solar proton events (SPEs).nWe conclude that (i) all 12 analyzed solar events, even those associated with fast halo CMEs originating from the central disk region, and those ICMEs and SPEs were not very geo‐effective. This unexpected result demonstrates that the suggested events in the chain (fast halo CME, X‐class flares, central disk region, ICME, and SPE) are not infallible proxies for geo‐effectiveness. (ii) The low value of integrated and normalized southward component of the interplanetary magnetic field ( Bz*) may explain the low geo-effectiveness for this small sample. In fact, Bz* is well correlated to the weak Dst and low auroral electrojet activity. Hence, the only space weather impact at Earth in 2002 we can explain is based on Bz* at L1.nWe discussed geo-effectiveness of the 12 X-class flare-CMEs in 2002 based on the available observations They failed to evoke strong disturbances since weak interplanetary magnetic field southward components The usual solar proxies (complex active region, X-class flare, and fast halo CME) are not sufficient to forecast geo-effectivity in 2002

Název v anglickém jazyce

Low Geo‐Effectiveness of Fast Halo CMEs Related to the 12 X‐Class Flares in 2002

Popis výsledku anglicky

It is generally accepted that extreme space weather events tend to be related to strong flares and fast halo coronal mass ejections (CMEs). In the present paper, we carefully identify the chain of events from the Sun to the Earth induced by all 12 X‐class flares that occurred in 2002. In this small sample, we find an unusual high rate (58%) of solar sources with a longitude larger than 74°. Yet all 12 X‐class flares are associated with at least one CME. The fast halo CMEs (50%) are related to interplanetary CMEs (ICMEs) at L1 and weak Dst minimum values (more than −51 nT), while five (41%) of the 12 X‐class flares are related to solar proton events (SPEs).nWe conclude that (i) all 12 analyzed solar events, even those associated with fast halo CMEs originating from the central disk region, and those ICMEs and SPEs were not very geo‐effective. This unexpected result demonstrates that the suggested events in the chain (fast halo CME, X‐class flares, central disk region, ICME, and SPE) are not infallible proxies for geo‐effectiveness. (ii) The low value of integrated and normalized southward component of the interplanetary magnetic field ( Bz*) may explain the low geo-effectiveness for this small sample. In fact, Bz* is well correlated to the weak Dst and low auroral electrojet activity. Hence, the only space weather impact at Earth in 2002 we can explain is based on Bz* at L1.nWe discussed geo-effectiveness of the 12 X-class flare-CMEs in 2002 based on the available observations They failed to evoke strong disturbances since weak interplanetary magnetic field southward components The usual solar proxies (complex active region, X-class flare, and fast halo CME) are not sufficient to forecast geo-effectivity in 2002

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10305 - Fluids and plasma physics (including surface physics)

Projekt

<a href="/cs/project/GA18-05285S" target="_blank" >GA18-05285S: Magnetosferické emise typu EMIC</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Geophysical Research: Space Physics

ISSN

2169-9380

e-ISSN

—

Svazek periodika

125

Číslo periodika v rámci svazku

6

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

23

Strana od-do

e2019JA027529

Kód UT WoS článku

000546578100001

EID výsledku v databázi Scopus

2-s2.0-85087093419