This award continues support for a cooperative program of round- the-clock joint observations of solar magnetic fields by the Big Bear Solar Observatory and the Huairou Solar Observing Station of Beijing Observatory. The observations will target the long-term evolution of solar magnetic fields. Particular problems to be addressed will be the polar rotation rate, the evolution of polar field elements, the evolution of active regions, the field changes associated with solar flares, and the flow of magnetic field elements across filament boundaries. This work must be done with China because Huairou has the only other videomagnetograph that operates regularly. The joint observing capability of the two observatories provides a powerful resource. No other solar observatories maintain regular or semi- continuous observations of magnetic fields. Magnetic fields are important to understanding the functioning of the sun and its effect on Earth.
