A global freeze, known as the Solar Minimum, is coming. It will see the strength of the sun decline by about 7% and lead to extensive freeze.
According to solar scientists, a similar event had occured in the 17th century (1645-1715) and the corresponding cold temperatures saw the river Thames (London) freeze, and the Baltic Sea as well — which permitted a Swedish army to infiltrate Denmark by rushing across the ice.
The exact commencement date is still debatable, but 2030 till 2050 covers the projection.
The 17th century incident is said to have also witnessed a reduction in ozone layer in the north, which allowed more UV radiation into the planet to modify the weather though the heating was not sufficient to offset the freeze.