Space Weather - Lost

Last week we talked a little bit more about Space Weather and what causes Space Weather. We also started to look at some of the impact Space Weather has on our daily life. There is a growing body of evidence indicating that changes in the geomagnetic field affect biological systems. Studies indicate that physically stressed human biological systems may respond to fluctuations in the geomagnetic field. Interest and concern in this subject have led the Union of Radio Science International to create a new commission entitled Electromagnetics in Biology and Medicine.

This is an artist's rendering of solar wind coming towards the Earth and its magnetosphere.

Possibly the most closely studied of the variable biological effects of the Sun has been the degradation of homing pigeons’ navigational abilities during geomagnetic storms. Pigeons and other migratory animals, such as dolphins and whales, have internal biological compasses composed of the mineral magnetite wrapped in bundles of nerve cells. While this probably is not their primarily method of navigation, there have been many pigeon race smashes during a geomagnetic storm. A smash is a term used when only a small percentage of birds return home from a release site. Because these losses have occurred during geomagnetic storms, pigeon handlers have learned to ask for geomagnetic alerts and warnings as an aid to scheduling races.

Ready, Set, Lost! 

Racing homing pigeons navigate incredible distances with apparent ease. A champion racing pigeon can be released 400 miles from its home loft, in a place it has never been before, and return within 1 day. The last 40 miles of its journey, the bird navigates by sight. But over the other 360 miles, the pigeon determines its way home by "sensing" the Earth's magnetic fields. We are not yet sure exactly how this mechanism works, but it does work -- extremely well.

Speedpigeon AU 02 LV 682 (I call him Moritz!)

How can the Sun affect racing pigeons?

When there is especially strong activity on the Sun, such as a Coronal Mass Ejection (CME), unusually strong surges of solar wind (charged particles from the Sun) can create a geomagnetic storm which distorts the Earth's normal magnetic field. The pigeons can no longer rely on their normal guidance system and may become lost. Thus wise pigeon racers, especially those in very northern areas, keep track of solar activity and do not fly their birds under certain geomagnetic conditions.

How do we measure geomagnetic activity?

Geomagnetic activity is measured by what we call the 'A' Index, which ranges from 0 to 400 Nanoteslas (nT), a measurement of the strength of a magnetic field. 0 indicates virtually no geomagnetic disturbance, while 400 is the maximum disturbance. Another useful number is the "K" index, which tracks changes in the radio atmosphere and can affect pigeon navigation. The K index ranges from zero (no disturbance) to 9 in a maximum disturbance.

24-hour Forecast: Geophysical Activity Forecast : The geomagnetic field is expected to be mostly unsettled to active with a slight chance for an isolated period of minor storming over the next 3 days (16-18 November). This activity is forecast because of elevated solar wind speeds near 650 km/s and intermittent periods of southward Bz, as well as a possible glancing blow from the CME on 13 November.

What levels of geomagnetic activity are dangerous for pigeons?

Any current reading of local figures over 150 nT in the A index of geomagnetic activity, or 4 or higher in 'K' index, is considered unsafe for training or racing pigeons.

Where can pigeon racers and fliers get solar activity data?

Geomagnetic stations track geomagnetic activity around the Earth. Their readings are freely available. The center of these activities in the USA is the Space Environment Center at Boulder, Colorado. There are other data centers in various parts of the world. Because the Earth's geomagnetic field emanates from the poles, the affects are more dramatic in the far north and far south. Thus pigeon racers need to rely on local data, that is, data that accurately represents the state of the geomagnetic field in their particular geographical location.