Modeling Space Weather

Understanding how the Sun affects what we do Jeffrey Hughes

“Space Weather” refers to conditions on the sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can influence the performance and reliability of space-borne and ground-based technological systems and endanger human life and health. Adverse conditions in the space environment can cause disruption of satellite operations, communications, navigation, and electronic power grids, leading to a panoply of socio-economic losses.

National Space Weather Program

Strategic Plan (March 1995)

“Don’t knock the weather; nine-tenths of the people couldn’t start a conversation if it didn’t change once in a while.”

-Kin Hubbard

“Climate is what we expect, weather is what we get.” - Mark Twain

Space Weather

SOHO EIT images EUV 195 A 1.5 million K

An Example of SXI Solar Imaging: Filament Eruption and Coronal Mass Ejection

LASCO Data Courtesy of SOHO

LASCO C2

02:42 UT

NOAA Space Weather Prediction Center

SXI 01:53UT

SXI 01:53UT

Solar Space Weather Inputs

• Photonic Radiation – X-rays and Radio Bursts

– Reach Earth in 8 minutes

• Particle Radiation – Solar Energetic Particles

– Reach Earth in 15 mins – 10’s hours

• Magnetic fields and plasma – Coronal Mass Ejections, High Speed Streams etc.

– Reach Earth in 1-3 days

– Cause geomagnetic storms

EPRI, 1996

How are We Affected by Space Weather?

NASA

L1 L2

GPS

Receiver

GPS

R. Viereck, NOAA/SEC Telstar 401

Satellite Systems

Power Transmission Space Habitation

Nav/ Comm Systems

MAS corona grid showing

magnetic field lines and solar

magnetogram- based boundary

field ( high spatial resolution

segment can be inserted for

modeling active an region)

CISM Solar & Coronal Models From solar magnetograms – maps of the surface magnetic field strength – to

models of the coronal magnetic.

Full-disk magnetogram

images of the Sun from

SOHO or ground based

observatories provide the

raw data.

Models use synoptic Field map(s) of the whole

solar surface built up over a 27-day solar rotation.

MHD modeling of the quasi-steady Coronal Magnetic Field

Solar Wind: ENLIL-Cone Model

• MHD model

• Fed by coronal model at inner boundary at 0.1 AU (21.5 Rsun)

• Cone model represents CME’s as plasma introduced at inner boundary.

• Now an operational model run on NWS NCEP computers every 2 hours.

Speed on 0.1 AU spherical inner boundary

Solar wind speed in equatorial plane

August 2010 - Animation

SWPC Model Transitions to Operations

• Solar Wind Disturbance Propagation Model – Geomagnetic storm predictions go from ~1 hour to 18hr - 4 days

• Energetic Particle Transport Model – Model to predict radiation storm peak intensity, timing, and spectrum; no models currently exist!

• Geospace Response Model – Will replace limited value global predictions with actionable regional forecasts and warnings

The proposed way forward to develop improved space weather models to maximize solar wind and CME data for extended forecast and warnings

transition to operations operations & maintenance

FY2011 FY2013 FY2015 FY2017+

O&M transition to operations Research and Development (R&D)

transition to operations R&D O&M

FY2012 FY2014 FY2016 O&M includes Operation to Research (O2R) feedback to continuing R&D

Operational Display (NCEP-SWPC)

Danielle’s poster

• Uses another heliospheric MHD model developed by Slava Merkin using the LFM code developed for magnetosphere.

• Validates model using Ulysses fast latitude scan observations.

• Tests sensitivity to inner boundary conditions

Coupled Geospace Models

E

Magnetosphere

LFM Model

Magnetosphere -

Ionosphere

Coupler

Ionosphere

Thermosphere

TIEGCM Model

Jll, np,Tp

Electric

Potential:

P Jll

Particle precipitation: Fe, E0 Conductivities: p h

Solar EUV

Coupled Magnetosphere Ionosphere Thermosphere Model (CMIT)

Plasma flows in the tail during a substorm (LFM simulation)

Sarah’s Poster • Driving CMIT with Enlil solar wind inputs

• Compares straight Enlil output with Enlil output with added Alfvenic noise to see what effect higher frequency variations have on the response of the magnetosphere

Katie’s Dissertation

• Adds ionospheric O+ outflow to inner boundary of LFM (multi-fluid version) to examine how O+ outflow affects magnetospheric shape and dynamics.