Understanding Magnetic Eruptions on the Sun and their Interplanetary Consequences

A Solar and Heliospheric A Solar and Heliospheric Research grant funded by the Research grant funded by the

DoD MURI programDoD MURI program

George H. Fisher, PIGeorge H. Fisher, PISpace Sciences LaboratorySpace Sciences Laboratory

University of California, BerkeleyUniversity of California, Berkeley

Goal

Develop a state-of-the-art, Develop a state-of-the-art, observationally tested 3-D observationally tested 3-D numerical modeling system for numerical modeling system for predicting magnetic eruptions on predicting magnetic eruptions on the Sun and the propagation of the Sun and the propagation of Coronal Mass Ejections (CMEs).Coronal Mass Ejections (CMEs).

Motivation

The Sun drives the magnetic eruptions that The Sun drives the magnetic eruptions that initiate violent space weather events. The initiate violent space weather events. The mechanisms that trigger and drive these mechanisms that trigger and drive these eruptions are the least understood aspects of eruptions are the least understood aspects of space weather. A better physical space weather. A better physical understanding of how magnetic eruptions understanding of how magnetic eruptions occur on the Sun and how the disturbances occur on the Sun and how the disturbances propagate through the Heliosphere will surely propagate through the Heliosphere will surely lead to more accurate and longer range lead to more accurate and longer range forecasts.forecasts.

Approach

Perform in-depth, coordinated space and Perform in-depth, coordinated space and ground based observations of magnetic ground based observations of magnetic eruptions and Coronal Mass Ejection (CME) eruptions and Coronal Mass Ejection (CME) propagationpropagation

Understand the physics of how magnetic Understand the physics of how magnetic eruptions are triggered and powerederuptions are triggered and powered

Develop numerical models for the initiation Develop numerical models for the initiation and propagation of CMEs and the and propagation of CMEs and the acceleration of Solar Energetic Particles acceleration of Solar Energetic Particles (SEPs)(SEPs)

Couple together the observationally tested Couple together the observationally tested models of the Sun and Heliospheremodels of the Sun and Heliosphere

Institutions of Solar Multidisciplinary University Research Initiative Team UC BerkeleyUC Berkeley Big Bear Solar Big Bear Solar

Observatory (NJIT) Observatory (NJIT) Drexel UniversityDrexel University Montana State Montana State

UniversityUniversity Stanford UniversityStanford University UC San DiegoUC San Diego University of University of

ColoradoColorado University of HawaiiUniversity of Hawaii University of New University of New

HampshireHampshire

Overview of Solar MURI 1. Active Region Emergence: Fisher & Abbett (UCB), LaBonte, Jing Li, & Mickey (UH), Canfield & Regnier (MSU), Liu (Stanford), Gallagher,Moon, Wang & Goode (BBSO)

2. Effects of Large Scale Field and Solar Cycle Evolution: Hoeksema, Scherrer, & Zhao (Stanford), Ledvina & Luhmann (UCB), Martens (MSU), Goode, Wang & Gallagher (BBSO)

3. Inner Corona: Forbes (UNH), MacNeice (Drexel), Abbett, Ledvina, Luhmann & Fisher (UCB), Kuhn & H. Lin (UH), Canfield & Longcope (MSU), Hoeksema, Scherrer & Zhao (Stanford)

4. Outer Corona, Solar Wind, SEPs: Odstrcil (CU), Jackson, Dunn & Hick (UCSD), MacNeice (Drexel), Luhmann & R. Lin (UCB), Lee (UNH)

5. Geoeffects: Luhmann & R. Lin (UCB), Odstrcil (CU), Hoeksema & Zhao (Stanford)

Website for Solar MURI Project: http://solarmuri.ssl.berkeley.edu

Accomplishments During 1st year Solar and Heliospheric MHD codes now Solar and Heliospheric MHD codes now

include adaptive mesh refinement, necessary include adaptive mesh refinement, necessary for a large dynamic range of spatial scalesfor a large dynamic range of spatial scales

CME observational data have been collected CME observational data have been collected and organized, and is accessible from a and organized, and is accessible from a single web page. Test cases for numerical single web page. Test cases for numerical modeling have been identified.modeling have been identified.

New observational capabilities are being New observational capabilities are being createdcreated

Community-based workshops have been Community-based workshops have been organized to address the most pressing organized to address the most pressing research problems.research problems.

Coupled Models of Emerging Magnetic Flux in Active Regions: an illustration of

AMR with Paramesh in “ZeusAMR”

Use ANMHD to model the rise of a Use ANMHD to model the rise of a modestly twisted active region modestly twisted active region through the solar convection zonethrough the solar convection zoneUse result from this simulation to Use result from this simulation to drive a fully compressible version of drive a fully compressible version of ZeusAMR, a merge of Zeus-3d with ZeusAMR, a merge of Zeus-3d with Paramesh (Abbett, Ledvina, & Paramesh (Abbett, Ledvina, & MacNeice)MacNeice)

The above figure shows a volume rendering of |B| in the ANMHD domain, which spans roughly 5 pressure scale heights.

A snapshot of a Zeus3D coronabeing driven by the emergingOmega loop of the previousslide. Magnetic fieldlines aretraced in blue, and the verticalcomponent of the magnetic field along the Zeus-3D lower boundary is shown as a greyscale image: the light areas represent regions of positive polarity, and dark areas represent negative polarity.

Here, no adaptive mesh is used,and as a result, only a small fraction of the emerging flux canbe modeled.

The figures above show a snapshot in time (from different vantage points) ofthe initially field-free ZeusAMR corona responding to this emerging Omega-loop. Note that the mesh has refined in the neighborhood of the active region and has de-refined elsewhere in response to a refinement criterion based on a normalized second derivative of the field strength.

Here, we show a close-up of the magnetic fieldlines in the low-corona just above the emerging bipole; the shaded contour along the vertical slice is the upward velocity of the plasma.In this figure, both the mesh and the block boundaries are shown.On a parallel computer, ZeusAMR allows for each block to be calculated on a separate processor. This scales well on parallel supercomputers, since each block (regardless of its physical dimensions) has the same number of cells (in this case, 8x8x8).

Accomplishments During 1st year Solar and Heliospheric MHD codes now Solar and Heliospheric MHD codes now

include adaptive mesh refinement, necessary include adaptive mesh refinement, necessary for a large dynamic range of spatial scalesfor a large dynamic range of spatial scales

CME observational data have been collected CME observational data have been collected and organized, and is accessible from a and organized, and is accessible from a single web page. Test cases for numerical single web page. Test cases for numerical modeling have been identified.modeling have been identified.

New observational capabilities are being New observational capabilities are being createdcreated

Community-based workshops have been Community-based workshops have been organized to address the most pressing organized to address the most pressing research problems.research problems.

Assembling a database of CME events (Yan Li)http://solarmuri.ssl.berkeley.edu/~yanli/public/htmls/events.htmlhttp://solarmuri.ssl.berkeley.edu/~yanli/public/htmls/events.html

The First MURI Case Study:  May 1 1998 - A Flare and CME from NOAA 8210

Photosphere: Continuum images of AR8210 show Photosphere: Continuum images of AR8210 show sunspot umbrae of opposite polarities within a single sunspot umbrae of opposite polarities within a single penubra. This configuration,known as a “penubra. This configuration,known as a “spot” spot” configuration, is known to be associated with major configuration, is known to be associated with major flares. flares.

Flux emergence and motions of sunspots are observed Flux emergence and motions of sunspots are observed (see Barry Labonte's movies at (see Barry Labonte's movies at http://www.solar.ifa.hawaii.edu/People/labonte/ivmflare/http://www.solar.ifa.hawaii.edu/People/labonte/ivmflare/ivmmovie1/ivm_19980501.htmlivmmovie1/ivm_19980501.html . .

A large number of vector magnetograms are available A large number of vector magnetograms are available both before and after the flare and CME; both before and after the flare and CME;

A map of the Full Sun longitudinal magnetic field is A map of the Full Sun longitudinal magnetic field is provided by the MDI/SOHO magnetograph.provided by the MDI/SOHO magnetograph.

Coronal Features of AR 8210

AR8210 is well observed by coronal AR8210 is well observed by coronal instruments such as CDS/SOHO, instruments such as CDS/SOHO, EIT/SOHO, SXT/Yohkoh, EIT/SOHO, SXT/Yohkoh, LASCO/SOHOLASCO/SOHO

A flare is observed in AR8210 near the A flare is observed in AR8210 near the disk center on May 1, 1998 disk center on May 1, 1998

A halo CME (toward the Earth) is A halo CME (toward the Earth) is associated with the flare of May 1, 1998 associated with the flare of May 1, 1998

Accomplishments During 1st year Solar and Heliospheric MHD codes now Solar and Heliospheric MHD codes now

include adaptive mesh refinement, necessary include adaptive mesh refinement, necessary for a large dynamic range of spatial scalesfor a large dynamic range of spatial scales

CME observational data have been collected CME observational data have been collected and organized, and is accessible from a and organized, and is accessible from a single web page. Test cases for numerical single web page. Test cases for numerical modeling have been identified.modeling have been identified.

New observational capabilities are being New observational capabilities are being createdcreated

Community-based workshops have been Community-based workshops have been organized to address the most pressing organized to address the most pressing research problems.research problems.

Coronal magnetic fieldsThe future for space weather prediction depends on directmeasurements of coronal magnetic fields. The infraredFeXIII line will allow this. Experimental determinationof coronal field strength from Zeeman splitting has beenobtained. Shortly the Haleakala observatory will providethese measurements for routine diagnostic use.

This EUV image shows contours of coronal Green-line emissionmeasured from the ground. The small box labeled A is a regionwhere infrared Zeeman field observations were obtained (below)

The infrared spectrum near 1000nm directly reveals the coronal magnetic field

This line profile is one of the first measurements of a 30G coronal magnetic field

Magnetic field inputs to space weather activity

On a daily basis the high altitude Mees observatory onHaleakala provides the solar vector magnetic field measurements required to model and predict the evolving interplanetary field configuration. This image shows the vector field from a bipolar Active region (number 1731) on February 21, 2002

The Haleakala observatory is the worlds highest elevation solar observatory. Itsits above 20% of the atmosphere and provides unrivaled infrared observingconditions.

Active Region Monitor(ARM;www.bbso.njit.edu/arm)

A web-based summary of the latest solar activity A web-based summary of the latest solar activity (every hour update)(every hour update)

BBSO H-alpha, SOHO EIT, MDI continuum and BBSO H-alpha, SOHO EIT, MDI continuum and magnetogram, Yohkoh SXT, GONG magnetogram, Yohkoh SXT, GONG magnetograms, GOES X-ray, and SEC event lists magnetograms, GOES X-ray, and SEC event lists etc.etc.

Trace back and after with an active regionTrace back and after with an active region Flare Prediction System based on McIntosh Flare Prediction System based on McIntosh

magnetic classmagnetic class

BBSO H- Movie(ftp.bbso.njit.edu/pub/archive)

- - Daily full-disk Daily full-disk - Flaring movie- Flaring movie - Sun online- Sun online - Global H-alpha- Global H-alpha NetworkNetwork

Accomplishments During 1st year Solar and Heliospheric MHD codes now Solar and Heliospheric MHD codes now

include adaptive mesh refinement, necessary include adaptive mesh refinement, necessary for a large dynamic range of spatial scalesfor a large dynamic range of spatial scales

CME observational data have been collected CME observational data have been collected and organized, and is accessible from a and organized, and is accessible from a single web page. Test cases for numerical single web page. Test cases for numerical modeling have been identified.modeling have been identified.

New observational capabilities are being New observational capabilities are being createdcreated

Community-based workshops have been Community-based workshops have been organized to address the most pressing organized to address the most pressing research problems.research problems.

MURI mini-workshops:

Use of synoptic, global scale magnetograms Use of synoptic, global scale magnetograms in coronal/heliospheric models (April 15, B. V. in coronal/heliospheric models (April 15, B. V. Jackson, Boulder)Jackson, Boulder)

Using vector magnetogram data in MHD Using vector magnetogram data in MHD simulation and other theoretical models (April simulation and other theoretical models (April 29, G.H. Fisher & R.C. Canfield, Berkeley)29, G.H. Fisher & R.C. Canfield, Berkeley)

Well defined numerical experiments for CME Well defined numerical experiments for CME eruption mechanisms (May 14-16, T.J. eruption mechanisms (May 14-16, T.J. Forbes, Durham NH)Forbes, Durham NH)

Summary

A great deal has been accomplished A great deal has been accomplished during the 1during the 1stst year year

Major challenges remain in numerical Major challenges remain in numerical code development and in the use of code development and in the use of solar data to drive numerical simulationssolar data to drive numerical simulations