Auroras Now

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Auroras Now!
Auroral nowcasting service for hotels, amateur
astronomers, and general public
Kauristie, K.1), Mälkki, A.1), Ketola,
A.1), Nevanlinna, H.1), Raita, T.2) , and Blanco,
A.1) 1) Finnish Meteorological institute 2)
University of Oulu
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Abstract
Auroras Now! is an auroral nowcasting system
utilizing magnetic field and all-sky camera
observations and cloudiness predictions made in
Finland. The service includes three parts a set
of public web-pages, a private service customized
for two hotels in Lapland, and a SMS-service for
the largest Finnish association of amateur
astronomers. The public part concentrates
especially to strong space weather events, while
the hotel service is adjusted to monitor also
moderate activity occurring within the standard
auroral zone. The core element of Auroras now!
is a robust auroral alarm system which follows
the hourly maximum of dH/dt and issues an alert
if the pre-defined threshold value gets exceeded.
Daytime alerts often serve as reliable
predictions for the forthcoming night's
activity.
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User feedback
The hotel system is usable (no technical problems
and no clouds) for 70 of the time and it can
characterize the auroral occurrence and intensity
of the forthcoming or on-going auroral activity
in 80 of the cases. Hotel clients are happy with
the performance. However, evaluating the
financial benefit is difficult. The marketing
value is important, but making a connection
between sales and this service is not obvious.
The SMS-service provides updates for the amateur
astromers also in the wilderness. The time
resolution could be higher, e.g.10 min. General
public web-site hits correlate with magnetic
activity. Daily average 140-220, peak values near
500 (March 11, 2004). The number of customers of
the freely available e-mail alerts has increased
from 160 to 490.
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Prospective for improvements
The coverage of auroral observations will be
improved by adding one more ASC to the system
(KEV, North-eastern Lapland) Short-term
predictions based on solar observations could be
integrated to the system. Collaboration with the
SIDC SDA (PRESTO) would be the most reasonable
way to do this improvement. If prediction
cababilities are added also warnings about their
caveats must be clearly announced. This is a
challenge especially for the hotel service where
the available space is limited. The hotel
customers do not necessarily have much background
knowledge and their tolerance for failures is
low. The hotel service would still need
efficient marketing to get more customers and a
24/7 helpdesk service to avoid annoying breaks
during the time of peak usage (which typically is
outside the normal office time).
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Auroral observations by MIRACLE

• Auroral latitudes Sodankylä Geophysical
  Observatory (SOD, MLAT 64)
• Sub-auroral latitudes Nurmijärvi Geophysical
  (NUR, MLAT 57)
• SOD magnetic field data and auroral images NUR
  magnetic field data
• Only stations with fixed Internet-connection can
  be used
• Digital auroral images
• 557.7 nm
• updated once per minute
• spatial resolution a few km
• Cloudiness predictions from FMI Regional Weather
  Service at Rovaniemi (the pink dot in the map)

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Public web-pages (1/2)

• http//aurora.fmi.fi
• Dynamic parts
• hourly updated bar plots of max(dH/dt)
• real-time auroral images during dark hours
• Archives
• previous night activity Magnetograms and ASC
  keograms from other MIRACLE stations
• cumulative records of max(dH/dt) values
• Evaluation of the auroral alarm system

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Public web-pages (2/2)

• Background information
• auroras and space weather
• prediction of auroral activity
• statistics about auroras
• description of the ESA pilot project
• Expert opinions
• weekly space weather reports
• replies to the questions from feedback forms

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Hotel service (1/2)

• A sequence of three pages (i) general info page
  from sun rise to noon, (ii) warm-up page from
  noon to sun set, and (iii) on-line page during
  dark hours.
• Appearance adjusted to be suitable for hotel-TV
  displays

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Hotel service (2/2)

• Dynamic parts Hourly updated magnetic activity
  monitor (1), Cloudiness predictions (2), near
  real-time ASC raw image (3), ASC image on map
  (4), and a recently acquired auroral animation
  (5).

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SMS service (1/2)

• Customer URSA, the largest Finnish association
  for amateur astronomers
• The service generates messages to the URSA system
  for rare optical phenomena.
• Santa Margarita Ltd provides a web-interface for
  adjusting the number of SMS-messages. The client
  can choose between the three different activity
  levels and geographic areas (northern and/or
  southern Finland).
• Price for the Santa Margarita service Yearly
  payment 24 euros 15 cnt per message.

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SMS service (2/2)

• Message must give a characterization of the
  activity (or occurrence probability) in a scale
  of three levels slightly enhanced, clearly
  enhanced and exceptionally strong activity
• The system makes also discrimination between the
  first alarms (either the first event of the night
  or change in the activity level) and updating
  alarms (activity continues on the same level).
• Instead of individual max(dH/Dt) values magnetic
  activity events are analysed
• Magnetic Disturbance Level (MDL) values depend
  both on the duration and peak dH/dt of the event
• MDL values are used also in the hotel service

Continuation of an on going event?
Start the record for a new event
Update the record of the ongoing event
Define the disturbance level and the label
(first or update) for the alert
Define the disturbance level and the label
(first or update) for the alert
Send the alert and save the disturbance level
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Halloween storm dH/dt
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Halloween storm dH/dt
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Halloween stormdH/dT
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Halloween storm Auroras
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Halloween storm as observed by Auroras Now!

• Red bars increased probability to see auroras
  (alarm on). Threshold at NUR (southern Finland)
  0.3 nT/s and at SOD (northern Finland) 0.5 nT/s.
• Time of continuous alarm started at SOD on Oct 28
  at 16 UT and at NUR on Oct 29 at 07 UT.
• The highest bars Oct 30 at SOD at 20 UT (18
  nT/s) and at NUR at 22 UT (14 nT/s) (c.f. the
  Malmö blackout took place on Oct 30 at 2007 UT)
• Activity continued at SOD during night time until
  the morning of Nov 4. Both SOD and NUR recorded a
  short re-intensification on Nov 4 during 06-11
  UT.
• Brightest auroras at SOD during Oct 28 21-24 UT
  and from Oct 29 17 UT to Oct 30 04 UT. Cloudy sky
  from the evening of Oct 30 to morning Nov 2.