A 20 year decline in solar photospheric magnetic fields: Inner‐heliospheric signatures and possible implications

@article{Janardhan2015A2Y,
  title={A 20 year decline in solar photospheric magnetic fields: Inner‐heliospheric signatures and possible implications},
  author={P. Janardhan and S. K. Bisoi and S. Ananthakrishnan and Munetoshi Tokumaru and Ken’ichi Fujiki and Lijo Jose and R. Sridharan},
  journal={Journal of Geophysical Research: Space Physics},
  year={2015},
  volume={120},
  pages={5306 - 5317}
}
We report observations of a steady 20 year decline of solar photospheric fields at latitudes ≥45° starting from ∼1995. This prolonged and continuing decline, combined with the fact that cycle 24 is already past its peak, implies that magnetic fields are likely to continue to decline until ∼2020, the expected minimum of the ongoing solar cycle 24. In addition, interplanetary scintillation observations of the inner heliosphere for the period 1983–2013 and in the distance range 0.2–0.8 AU have… 

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