Rivers react to sun's activity

''Though scientists reject the climate sceptics' assertion that the sun's activity can explain global warming, many have wondered whether it can affect rainfall. No one has been able to test this, though, as it has proved difficult to collate rainfall measurements over long timescales and areas large enough to rule out local variations.
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Mauas's team compared the streamflow with an indicator of solar activity: the number of sunspots seen each year on the sun's surface. The more there are, the greater the sun's activity. The researchers found that over a timescale of decades, the streamflow in the Paraná increased and decreased in accordance with the number of sunspots. "There is less than a 0.01 per cent chance that this correlation is by chance," says Mauas.'' [source]