A paper published today in The Holocene finds that short term changes in solar activity have had a major influence on heavy rainfall and flooding along the Lower Yellow River in China over the past ~2000 years. The authors find that when sunspot numbers decline during the 2nd half of solar cycles, heavy rainfall is more common. This would tend to support the Svensmark theory of cosmoclimatology, as declining solar activity leads to increased cosmic rays forming clouds, and hence increased rainfall. Once again, more evidence accumulates that tiny variations of solar activity can be amplified to large changes in climate on Earth.
Influence of solar activity on breaching, overflowing and course-shifting events of the Lower Yellow River in the late Holocene