In 1883 the volcano Krakatoa erupted and cooled the planet:
In the year following the eruption, average global temperatures fell by as much as 1.2 degrees Celsius. Weather patterns continued to be chaotic for years, and temperatures did not return to normal until 1888. The eruption injected an unusually large amount of sulfur dioxide (SO2) gas high into the stratosphere which was subsequently transported by high-level winds all over the planet. This led to a global increase in sulfurous acid (H2SO3) concentration in high-level cirrus clouds. The resulting increase in cloud reflectivity (or albedo) would reflect more incoming light from the sun than usual, and cool the entire planet until the suspended sulfur fell to the ground as acid precipitation.
Earlier that century gave us the “Year without Summer”:
Most consider the climate anomaly to have been caused by a combination of a historic low in solar activity and a volcanic winter event; the latter caused by a succession of major volcanic eruptions capped off by the Mount Tambora eruption of 1815, the largest known eruption in over 1,600 years.
The proven, frequent, even likely, threat to our society is from COLD. We need more energy and a broad mesh of different food creation and distribution networks.
Does what the Greens and Socialists propose make you feel warm and fuzzy about being cold?