[Isocops] Oranae Flag Storm Conditions

[Nathan Schwadron]

Hi All

Currently the >10 MeV flux is still hovering just above 100 part./cm2-s-sr. I am maintaining the storm alert flag at Orange. 

I have included some of the information on the activity forecast. Region 1429 continues to be active and well connected over the next few days. If we have M-class flares, we expect to continue to have Orange flag conditions. However, there is a possibility of another X-class flare, which could lead to Red flag conditions. 

Below I have included the forecast and a definition of spaceweather conditions from SWPC. You will see that our designations of red/orange/yellow flags correspond roughly to strong/moderate/minor conditions from SWPC. Also note that we expect the number of such events  as follow

Red: 10 events
Orange: 25 events
Yellow: 50 events

At this time the only difference between our red flag and the "strong" SWPC definition is that the red flag can be triggered by the 38-82 MeV flux exceeding 2.6 part./cm2-s-sr-MeV. Currently, this 38-82 MeV flux is at 0.4 part./cm2-s-sr-MeV, which is well below the red flag level. 

IA.  Analysis of Solar Active Regions and Activity from  08/2100Z
to 09/2100Z:  Solar activity reached high levels today.  Region 1429
(N18W13) produced an M6 flare at 09/0353Z.  Associated with this
event was Type II (1285 km/s) and Type IV radio sweeps along with a
full halo CME first seen in SOHO/LASCO C2 imagery at 09/0426Z.  The
CME had an estimated plane-of-sky speed of 850 km/s in STEREO B COR2
imagery.  Separation and slight decay within the intermediate area
was observed in Region 1429, however it still remained a large Ekc
spot group with a Beta-Gamma-Delta magnetic configuration.  A new
spot group rotated onto the NE limb and was numbered Region 1432
(N18E69).  This new region is too close to the limb to accurately
determine the spot and magnetic classification, however it produced
a C9 flare at 09/2025Z.

IB.  Solar Activity Forecast:  Solar activity is expected to continue
at low to moderate levels with a chance for X-class activity from
Region 1429 for the next three days (10 - 12 March).


I have included a chart below from the SWPC chart which indicates some of the basis for our definition of flag levels.



Category

Effect

Physical measure

Average Frequency
(1 cycle = 11 years)

Scale

Descriptor

Duration of event will influence severity of effects

 	 
Solar Radiation Storms

Flux level of >= 10 MeV particles (ions)*

Number of events when flux level was met (number of storm days**)

S 5

Extreme

Biological: unavoidable high radiation hazard to astronauts on EVA (extra-vehicular activity); passengers and crew in high-flying aircraft at high latitudes may be exposed to radiation risk.***

Satellite operations: satellites may be rendered useless, memory impacts can cause loss of control, may cause serious noise in image data, star-trackers may be unable to locate sources; permanent damage to solar panels possible.

Other systems: complete blackout of HF (high frequency) communications possible through the polar regions, and position errors make navigation operations extremely difficult.

105

Fewer than 1 per cycle

S 4

Severe

Biological: unavoidable radiation hazard to astronauts on EVA; passengers and crew in high-flying aircraft at high latitudes may be exposed to radiation risk.***

Satellite operations: may experience memory device problems and noise on imaging systems; star-tracker problems may cause orientation problems, and solar panel efficiency can be degraded.

Other systems: blackout of HF radio communications through the polar regions and increased navigation errors over several days are likely.

104

3 per cycle


S 3

Strong

Biological: radiation hazard avoidance recommended for astronauts on EVA; passengers and crew in high-flying aircraft at high latitudes may be exposed to radiation risk.***

Satellite operations: single-event upsets, noise in imaging systems, and slight reduction of efficiency in solar panel are likely.

Other systems: degraded HF radio propagation through the polar regions and navigation position errors likely.

103

10 per cycle


S 2

Moderate

Biological: passengers and crew in high-flying aircraft at high latitudes may be exposed to elevated radiation risk.***

Satellite operations: infrequent single-event upsets possible.

Other systems: small effects on HF propagation through the polar regions and navigation at polar cap locations possibly affected.

102

25 per cycle

S 1

Minor

Biological: none.

Satellite operations: none.

Other systems: minor impacts on HF radio in the polar regions.

10

50 per cycle


Nathan Schwadron
n.schwadron at unh.edu

University of New Hampshire
Morse Hall - Room 353
8 College Road
Durham NH 03824
USA

(603) 862-3451



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