[Calbuco as seen from the nearby city of Puerto Montt (southern Chile)]
There was a massive double eruption on Wednesday by Chile’s Calbuco volcano – its first activity in 42 years - and it sent a massive ash plume high up into the sky (photo above from nearby town). This eruption could have an impact on worldwide climate depending on its duration and ultimate extent of the ash plume into high-levels of the atmosphere. Past history has shown that large volcanic eruptions can generate a year or so of global cooling. When enough ash and dust is ejected into the lower stratosphere, these particles then spread across the globe due by upper-level wind currents. These increased aerosols in the upper atmosphere can then act to reflect the incoming solar radiation back into space rather than allowing penetration into the troposphere and the warming the surface of the earth. The term that is often used that describes a period of time that results in cooling temperatures following a major volcanic eruption is “Volcanic Winter”. The most famous recent volcanic eruption that resulted in "Volcanic Winter" was Mount Pinatubo (Philippines) in 1991 which resulted in reduced global temperatures for the following 2-3 years. Way back in 1883, the explosion of Krakatoa (Indonesia) created volcanic winter-like conditions for the subsequent four years with unusual year-round cold and record snowfalls worldwide.
[Enhanced IR satellite image of the “volcano-produced” cloud]
The volcano is located about 600 miles south of Santiago, and just a few miles from the city of Puerto Varas. Evacuations were ordered for a 12-mile radius around the volcano. The eruptions happened after a series of earthquakes, the Chilean Interior Ministry reported. The column of smoke and ash rose more than 9 miles into the atmosphere and can be clearly seen in an enhanced IR satellite image (middle). Pyrocumulus clouds form when intense heat at the ground causes air to rise rapidly such as what can occur during volcanic eruptions or wildfires. In the case of exceptionally strong updrafts, pyrocumulonimbus clouds are possible, which can produce rainfall and lightning (bottom photo). Dust and ash particles that get thrown up into the atmosphere can separate into positively and negatively charged groups. Lightning can result when this charge separation becomes too great for air to resist the flow of electricity. The volcano may soon start oozing lava and cause the melting of ice, and ultimately floods, and a third major eruption is possible in the very near term.
[Lightning captured in photos on Wednesday night]