{"id":57866,"date":"2022-01-18T09:41:56","date_gmt":"2022-01-17T23:11:56","guid":{"rendered":"https:\/\/www.solarquotes.com.au\/blog\/?p=57866"},"modified":"2024-10-02T12:51:59","modified_gmt":"2024-10-02T03:21:59","slug":"tonga-eruption-cooling-solar","status":"publish","type":"post","link":"https:\/\/www.solarquotes.com.au\/blog\/tonga-eruption-cooling-solar\/","title":{"rendered":"Tonga Eruption Won’t Cool Planet Or Reduce Solar Output"},"content":{"rendered":"

\"Tonga<\/p>\r\n

After I heard about the Tongan volcanic eruption, the first thing I did was determine if the Tongans I knew were all right.\u00a0 While conditions there are serious, they aren’t as bad as they could have been, so they’re probably okay.\u00a0 Australia and New Zealand are sending relief, which is a relief.\u00a0<\/p>\r\n

The second thing I did was try to determine if the massive eruption would result in global cooling like the Mt. Pinatubo<\/a> eruption in the Philippines back in 1991.\u00a0<\/p>\r\n

The answer to that is, despite being a massive eruption, insufficient material was blown high enough into the stratosphere<\/a> to cause global cooling.\u00a0<\/p>\r\n

I see some people celebrating this fact and saying the world dodged a bullet because there won’t be a repeat of the 1816 “year without a summer<\/a>” after the eruption of Mt. Tambora<\/a>. \u00a0<\/p>\r\n

On the — literal — bright side, the Tonga eruption won’t contribute to global dimming and reduce the amount of sunlight reaching the ground.\u00a0 This means — unless volcanic ash lands on them– the eruption <\/span>won’t reduce the output of solar power systems.<\/p>\r\n

Because a South Seas volcano won’t be giving us any temporary respite from the global roasting we’re subjecting ourselves to, the reasons for rapidly reducing fossil fuel use remain as strong as ever.\u00a0 At least there will be no minor dip in solar energy generation getting in the way of that.<\/p>\r\n

Big Eruptions Can Cool The World<\/h2>\r\n

Massive volcanic eruptions can temporarily cool the world by releasing sulphur dioxide<\/a> into the atmosphere.\u00a0 This forms tiny solid sulphate<\/a> particles and tiny droplets of sulfuric acid<\/a>.\u00a0 While their exact effects are complex, they function as anti-greenhouse gases and reflect the sun’s heat into space before it reaches the ground.\u00a0\u00a0<\/p>\r\n

Normally, they don’t hang around for long.\u00a0 They settle to the ground because they’re heavier than air or are washed out by rain.\u00a0 In the troposphere<\/a>, which is the part of the atmosphere we’re most familiar with and extends from the ground to a bit past the top of Mount Everest1<\/a><\/sup>, sulphur compounds have a half-life of around ten days.\u00a0 This means, no matter how much sulphur a volcanic eruption spews into this atmospheric layer, there will only be about 1% left after two months, so no prolonged cooling is possible.\u00a0<\/p>\r\n

To cause significant global cooling, enough sulphur has to be blown past the troposphere into the next layer, which is the stratosphere<\/a>.\u00a0 Down around Hobart, the stratosphere is about 10 km up, but in the tropics, it starts at around 17 km and at times, its boundary can be up to 20 km high.\u00a0 While this layer is too high and dry for rain, sulphur compounds still normally only last weeks or months here because they continue to drift downwards due to gravity.\u00a0<\/p>\r\n

To cause significant global cooling, enough sulphur compounds have to reach the part of the stratosphere where Brewer-Dobson Circulation<\/a> occurs.\u00a0 This is where the stratosphere rises in the topics and circulates to the poles, where it falls again.\u00a0 This uplift can potentially keep sulphur compounds in the upper atmosphere for years.\u00a0<\/p>\r\n

Tonga Eruption Wasn’t Big Enough<\/h2>\r\n

The Tonga eruption was massive.\u00a0 While calculations are crude, one estimate<\/a> puts the explosion at a little under 50 megatons<\/a>.\u00a0 That makes it almost equal to the largest nuclear explosion<\/a> ever created by human beings.\u00a0<\/p>\r\n

The massive Krakatoa eruption in Indonesia in 1883 was estimated to be 200 megatons.\u00a0 So, in the Australian vernacular, this would make Tonga a quarter-Kraka.<\/p>\r\n

The Mount Pinatubo eruption in the Philippines in 1991 was estimated to be 70 megatons<\/a>.\u00a0 This eruption blew roughly 17 million tonnes of sulphur into the atmosphere and resulted in significant global cooling of around 0.5 degrees in the northern hemisphere for two years.\u00a0<\/p>\r\n

Under the right circumstances, the Tonga eruption may have resulted in global cooling, but it simply hasn’t thrown sufficient material high enough into the atmosphere for that to occur.\u00a0 Cooling effects will only be local — a very big local, but still local as far as the world is concerned — and temporary.\u00a0 The world will also miss out on spectacular sunrises and sunsets caused by stratospheric sulphur aerosols<\/a>, but Queensland may see some impressive ones.<\/p>\r\n

Previous Volcanic Cooling Events<\/h2>\r\n

In the past 200 years, there have been four eruptions resulting in significant global cooling.\u00a0 These eruptions and the estimated amount of cooling they caused in the northern hemisphere were:<\/p>\r\n