# Presentation: 349377

## Slide 1

**Notes:**
SPE on Oct 29-30 was the 4th largest event in 40 years. There are 4 periods of enhanced SEPs, with the largest one on Oct 28-29.

## Energetic Protons Observed by NOAA-POSE

**00 UT, 28 October 2003**

**10****7**

**10****4**

**10****-2**

**1**

**Protons/cm****2****-sec**

**Protons/cm****2****-sec**

**30-80 keV**

**80-240 keV**

**240-800 keV**

**2.5-6.9 MeV**

**6.9-16 MeV**

**16-35 MeV**

## Energetic Protons Observed by NOAA-POSE

**06 UT, 29 October 2003**

**10****7**

**10****4**

**10****-2**

**1**

**Protons/cm****2****-sec**

**Protons/cm****2****-sec**

**30-80 keV**

**80-240 keV**

**240-800 keV**

**2.5-6.9 MeV**

**6.9-16 MeV**

**16-35 MeV**

## % Change of Electron Density due to SEPs

**October 27 – November 5, 2003**

**October 27 – November 5, 2003**

**Northern Polar Cap**

**Southern Polar Cap**

**Notes:**
SPE of MeV energies dissipate below 100 km. These plots show the % change of Ne over Eureka in northern Canada, and over the Antarctic between Oct 27 – Nov 5.

## Riometer Absorption at South Pole (Courtesy of Alan Weatherwax)

**Riometer Absorption at South Pole (****Courtesy of Alan Weatherwax****)**

**Oct 28**

**Oct 30**

**Oct 29**

**Oct 31**

**Notes:**
The enhanced Ne in the D-region ionosphere was colloborated by reometer observation. Reometers measure cosmic ray absorptions in the D-region. Increased D-region electron density increases such an absorption. The reometer station over South Pole measured very strong absorption on Oct 28-29, and somewhat weaker absorption on Oct 30, consistent with the intensity of SPE fluxes on these days.

## Absorption from the SGO Riometer Chain

**Courtesy of Andrew Kavanagh**

## Changes of NOX (NO+NO2) and Ozone due to SEPs

**Changes of NO****X ****(NO+NO****2****) and Ozone due to SEPs**

**October 27 – December 31, 2003**

**October 27 – December 31, 2003**

**O****3**

**NO****X**

**O****3**

**NO****X**

**Notes:**
While the response in electron density to SEPs is somewhat spontaneous, the eefects of SPE on the neutral atmosphere is long lasting.
the period plottede here is from Oct 27 until the end of the year.
 During SPE, NO is a result of N2 and O2 dissociation
 NOx and HOx cause catalytic Ozone destruction
 Once generate, the Ozone depletion lasts for many months

## TN During Flare at ~450 km

**T****N**** During Flare at ~450 km**

**Oct 28 1000UT**

**Oct 28 1200UT**

**Oct 28 1400UT**

**Oct 28 1600UT**

**Oct 28 1800UT**

**Oct 28 2000UT**

**Notes:**
Flare started ~11 UT.

## Difference TN During Flare at ~450 km

**Difference T****N**** During Flare at ~450 km**

**Oct 28 1000UT**

**Oct 28 1200UT**

**Oct 28 1400UT**

**Oct 28 1600UT**

**Oct 28 1800UT**

**Oct 28 2000UT**

## What we know about effects of SEPs and solar flares on the ionosphere/upper atmosphere:

**SEPs cause > 2 orders of magnitude increase in Ne in the D-region**
**Causing long-term changes of neutral composition in the mesosphere and upper stratosphere**
**Thermospheric temperature, neutral density, and TEC all increase in the thermosphere due to flares**

**What we don’t know:**
** ****How deep SEPs can penetrate to the Mars upper atmosphere**
**The short and long-term effects: how different or similar compared to the terrestrial upper atmosphere/ionosphere**

**What we need to get there:**
**	****Using comprehensive observations to constrain GCMs for Mars**

## Difference TN During Storm at ~450 km

**Notes:**
The thermospheric response to flare, however, is quite different from geomagnetic storms.

## Slide 12