1CISM Advisory Council Meeting 4 March 2003

Ionosphere-Thermosphere Modeling

Tim Killeen, Stan Solomon,

and the CISM Ionosphere-Thermosphere Team

2CISM Advisory Council Meeting 4 March 2003

Ionosphere-Thermosphere Overview

3CISM Advisory Council Meeting 4 March 2003

Perturbations in the Ionosphere-Thermosphere System

Positive & Negative ionospheric storm effects (TIE-GCM simulation,

R. Roble, B. Foster)Changes in neutral density following geomagnetic

disturbances alters satellite orbits due to atmospheric drag, resulting in tracking anomalies

4CISM Advisory Council Meeting 4 March 2003

Magnetosphere - Ionosphere Coupling

E

LFM Model

Magnetosphere -Ionosphere Coupler

TING Model

Jll, np,Tp

Conductivities:ph

Electric potential:

P

Jll

Particle precipitation: Fe, E0

One Way Coupling Two Way Coupling

5CISM Advisory Council Meeting 4 March 2003

Comparison of Coupled Models — Energy Flux & Ion Drift

One Way Coupling Two Way Coupling

6CISM Advisory Council Meeting 4 March 2003

Comparison of Coupled Models — Conductivities

One Way Coupling Two Way Coupling

7CISM Advisory Council Meeting 4 March 2003

Current Research: High-Resolution Polar Cap Modelwith Multiple Levels of Nested Grids

Regular Grid (5°) Nested Grid (~1°)

Electron Densities at F2 Peak (pressure level 2.0)

8CISM Advisory Council Meeting 4 March 2003

Ionosphere-Thermosphere Validation Matrix

1 Below ~130 km2 O/N2 during the day, electron densities at night, also coupling parameters. Useful composition data could not be obtained from POLAR and IMAGE‡ In situ or mainly in situ measurements, DE 2 and AE were multi-instrumented missions† Only some of these variables were available on any particular rocket flight. Generally sporadic. 3 Derived quantities with assumptions

Tn U V O2 N2 O NO N nn ne O+ NO+ O2+ Te Ti ui vi

ISRs x1 x1 x1 x x x x xDigisondes x x xSuperDarn x xImagers x2 x2 x2

Accelerometers‡ xSatellite Drag‡ xDE 2‡ x x x x x x x x x x x x xAE‡ x x x x x x x x x x x xGPS systems xDMSP/NOAA x x x x3 x3

TIMED x x x x x xSNOE xGround FPI x x xGroundImagerArchivedRocket† xx xx xx xx xx xx xx

9CISM Advisory Council Meeting 4 March 2003

M-I Coupling Validation Matrix

1 AMIE uses measurements of B by ground-based magnetometers and of E and B from DMSP and NOAA satellites. The resulting conductivities and potential pattern are reconciled, so the errors in potential are not large. However, the original estimates of conductivies come from ISR measurements that were developed using a Bates profile to describe the neutral atmosphere to derive the collision frequency. A Bates profile is not an accurate description of the thermosphere, especially in regions of auroral precipitation. Low latitude conductivities should not be used at all (see validation document).2 See 1 for the difficulties with ISR conductivities.3 Derived quantities with assumptions.* Archived DE 2, UARS data† Imagers provide measures of brightnesses in the UV. E0 and F can be derived from these brightnesses‡ In situ

B E V ui,vi E0 F Precip J_ Jp JH P H

AMIE x1 x3 x1 x1

ISRs x3 x3 x x3 x3 x2,3 x2,3

NOAA‡ x x3

DMSP‡ x x3 x3 x3 x x3

GBMagnetometers x x3 x3 x3 x3 x3 x3

Iridium‡ x x3

DirectParticl *e ‡ x3 x3 xSuperDARN x3 x3 xImagers† x3

10CISM Advisory Council Meeting 4 March 2003

Rationale• A robust set of metrics are needed that will be available for the foreseeable future.• The data used for these metrics should not be subject to uncorrectable instrument drift and should be measured in the same way all the time.• These metrics should reflect those developed by the Space Weather Programs metrics panel as closely as possible.

Plan• Proposed metrics for the ionosphere: the maximum electron density at the F2 peak; the height of the F2 peak; and as a secondary product the maximum electron density at the E-region peak.• Densities will come from ionosondes and height from incoherent scatter radars, although GPS measurements should also be considered when they become routine.• Proposed metrics for the thermosphere: satellite drag and accelerometer densities; FPI red line temperatures; and O/N2 from satellite imaging when it becomes regularly available.

Metrics

11CISM Advisory Council Meeting 4 March 2003

Research Plan OutlineYear 1

Complete preliminary coupling of the TING model to the Dartmouth MHD model. (70%)Test magnetosphere/ionosphere model with observations with and AMIE analysis. (10%)Begin transition to nested-grid version of the TIE-GCM coupled with the MHD model. (50%)Participate in development of model coupling framework design and specifications. (90%)

Year 2Couple MHD model and Rice convection model with the TIE-GCM.Implement multi-processor version of coupled model, using coupling framework.Initiate observational validation of magnetosphere/ionosphere coupled model.Initiate development of graphical interfaces for output analysis.

Year 3Initiate development of algorithms to assimilate observational data into the TIE-GCM.Continue observational validation of magnetosphere/ionosphere coupled model.Continue development of graphical interfaces for output analysis.Support coupling of solar wind model to magnetospheric model to create CISM model.

Year 4Extend TIE-GCM altitude range to include the plasmasphere.Integrate new TIE-GCM with magnetosphere MHD model and Rice convection model.Support validation of CISM model with observations.Support installation of CISM model on NCAR computational facilities.

Year 5Transition to pre-operational model on special-purpose NCAR computational facility.Implement data assimilation system with CISM model.Conclude observational validation activities.Conclude graphical interface development activities.

12CISM Advisory Council Meeting 4 March 2003

Meetings & Activities

• Magnetosphere-Ionosphere coupling meetingMonthly, Access Grid

• NCAR-wide general CISM meetingMonthly, HAO

• Ionosphere-Thermosphere model development meetingBi-Weekly, HAO

• CISM executive committeeBi-Weekly, Telecon

• CISM general meetingsMay kickoff, September retreat, March advisory council

• Space Weather Summer SchoolLectures & Labs, BU

13CISM Advisory Council Meeting 4 March 2003

Issues and Challenges

• Auroral energy flux and conductivity feedback (including solar ionization)

— parameterization of auroral acceleration

• Three-way coupling with the LFM and RCM

— unified solution to potential fields?

• Plasmasphere - ionosphere interactions

— incorporation of plasmasphere model into TIE-GCM

• Ion outflow

• Sub-grid-scale phenomena and model resolution

• Lower and middle atmosphere effects

• Validation & metrics

• Approach to data assimilation