Kp index vs WSA-ENLIL Solar Wind Prediction

[oemSpace]

Referring to following link,  I would like to know on which one is more accuracy on measuring CME, Kp Index showed G1 on 26 Sep, but there is no plasma between 26 - 27 Sep on WSA-ENLIL Solar Wind Prediction.

 

Kp Index showed G1 on 26 Sep

https://1drv.ms/u/s!AuvJV0hx3xTGiFNmU-8gkqXGNqrC?e=tIo47M

 

There is no plasma between 26 - 27 Sep on WSA-ENLIL Solar Wind Prediction

https://1drv.ms/u/s!AuvJV0hx3xTGiFTtDP9g4ayxA_NI?e=M6EfOH

 

There is no feature to insert image from PC, so I only can provide link.

Does anyone have any suggestions?
Thanks in advance

 

Edited September 26, 2020 by oemSpace

[Jesterface23]

The WSA-ENLIL is a forecasting model run of the solar wind, and CMEs when they occur.

You will want to look more into Coronal Hole High Speed Streams to understand the forecasting model.

https://www.spaceweatherlive.com/en/help

[oemSpace]

Since Kp-index doe not include solar wind and IMF data, for beginner, with the data of these magnetometers,

1) would Kp-value be the basic way of telling us any coming geomagnetic disturbance?

2) does Kp-value measure on Earth's surface or atmosphere or space?

3) Geomagnetic storming starts at a Kp of 5, does it include direction of IMF as well? such as southward (negative) then this causes a good connection with Earth’s magnetic field

4) is there any source to get IMF direction in text format?

Do you have any suggestions?
Thank you very much for any suggestions (^v^)

 

Edited September 27, 2020 by oemSpace

[Vancanneyt Sander]

Kp only tells us the global geomagnetic activity of the past three hours based on magnetometer readings from a number of stations on Earth.

Kp is solely based on the K-indices of the magnetometer stations. Please see the help section of SpaceWeatherLive

the direction of the IMF is important to have geomagnetic storming at all. When it’s south over a longer period of time, storming will enhance and magnetometers will show that. If it wobbles between south and north it won’t give much. If it stays north it won’t be much of a storm. 

[oemSpace]

Kp-indices can access in text format, I would like to know on whether Kp-indices calculation include direction of IMF or not, if not, is there any source to access direction of IMF in text format?

Do you have any suggestions?
Thanks, to everyone very much for any suggestions (^v^)

 

Edited September 27, 2020 by oemSpace

[Vancanneyt Sander]

as I've said: Kp indices are based on K-indices readings from magnetometer stations. So that does NOT include IMF readings as it only contains magnetometer readings as input to derive a local K-indice from which Kp is calculated of.

Just check our site to know if IMF is southward or not, no need for txt... If Bz is below zero , the direction is negative (because the IMF is a vector component with Z being the direction of the field)

[oemSpace]

I would like to know on how to interpret the impact on Earth based on following conditions:

I find the direction of IMF keep changing all the time, how to apply direction of IMF in real life?

1) Kp-indices = 6 and Bz level = 1 nT North

2) Kp-indices = 6 and Bz level = -1 nT South

Do you have any suggestions on what difference is about impacting on Earth?

Thanks, to everyone very much for suggestions (^v^)

Edited September 27, 2020 by oemSpace

[Vancanneyt Sander]

Kp is from the PAST three hours, so if you see that Bz is north now, it's still up to 60 minutes away from Earth before a magnetometer would react to it. When we send out a Kp alert, it means that at one of the magnetometer stations, the threshold was reached for that Kp value in the current three hour range. But you need to look back in Time to know what the IMF did at that time, that's why our graphs show an Earth line to get an idea of what data has arrived at Earth and what's still there to come.

[Jesterface23]

Data from satellites can give us a ~30 minutes heads up, but satellite's mag data doesn't determine the Kp index.

The Kp Index has a use for forecasting and real time activity in intervals.

The forecasted Kp Index comes from model runs, while real time is from many geomagnetic observatories in many locations across the globe. 

Kp is the Planetary K-Index. Each observatory has their individual K-Index.

This will help some, 

http://k9la.us/Where_Do_the_K_and_A_Indices_Come_From.PDF

https://www.swpc.noaa.gov/products/station-k-and-indices

Edited September 27, 2020 by Jesterface23

[oemSpace]

Since most of record show IMF below 0 (south), would following statement correct to interpret Bz?

1) Kp-indices = 6 and Bz level = 1 nT North, referring to what's still there to come, correct?

2) Kp-indices = 6 and Bz level = -1 nT South, referring to arrive at Earth, correct?

 

Furthermore, would following link be correct for real time activity?

https://www.spaceweatherlive.com/en/reports/noaa-swpc-alerts-watches-and-warnings

Do you have any suggestions?

Thanks, to everyone very much for suggestions (^v^)

 

Bz level    0.37 nT north, it refers to direction of IMF.
Bt level    5.12 nT, does Bt level refer to Kp-indice?

Do you have any suggestions?

Thanks, to everyone very much for suggestions (^v^)

 

[Vancanneyt Sander]

Kp6 can only be reached after a prolonged period of southward directed Bz below -10nT and much lower (with moderate to strong Bt, moderate hemispheric power, a good high solar wind,...). Bz can not be lower than the total field strength (Bt)

and yes that link has real time info, but also our Twitter page has live alerts and also our SpaceWeatherLive app.

[Christopher S.]

No. Give this a read: https://en.wikipedia.org/wiki/K-index and for a more technical summary, this: https://www.swpc.noaa.gov/sites/default/files/images/u2/TheK-index.pdf

[oemSpace]

Thanks, to everyone very much for suggestions (^v^)