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The earth is warming at a rate of four Hiroshima bombs per second [1] primarily because of human actions. I haven't read your document but it sounds like you're

The earth is warming at a rate of four Hiroshima bombs per second [1] primarily because of human actions. I haven't read your document but it sounds like you're grossly underestimating our energy output. [1] https://archive.thinkprogress.org/earths-rate-of-global-warming-is-400-000-hiroshima-bombs-a-day-44689384fef9/ https://archive.thinkprogress.org/earths-rate-of-global-warm...

samatman 6y ago
Regarding Toba, Le Wik has this to say: The erupted mass was, at the very least, 12 times greater than that of the largest volcanic eruption in recent history, the 1815 eruption of Mount Tambora in Indonesia, which caused the 1816 "Year Without a Summer" in the Northern Hemisphere.[8] Toba's erupted mass deposited an ash layer of about 15 centimetres (5.9 in) thick over the whole of South Asia. A blanket of volcanic ash was also deposited over the Indian Ocean, the Arabian Sea, and the South China Sea.[9] Deep-sea cores retrieved from the South China Sea have extended the known reach of the eruption, suggesting that the 2,800 km³ calculation of the erupted mass is a minimum value or even an underestimate.[10] Based on new methods (crystal concentration and exponential), the Lake Toba Caldera possibly erupted as much as 3,200 km³ of ignimbrite and co-ignimbrite. I think its more likely your cursory dismissal which is failing to appreciate the magnitude of this event, than that the person who is actually crunching the numbers is getting it wrong. But what do I know?
- pmayrgundter 6y ago
  I spent some more time on this and now have a comparison table, with citations in my doc. V8 volcanoes still look more energetic and happen once every million years. @ancientworldnow, I'd note that the figure of 4 Hiroshimas/second is the measure of Global Warming, not of human energy production. Hansen acknowledges this in the linked TED talk from your citation, at about 7 minutes in ("it's about 20 times greater than all the energy used by humanity"). To get a sense of comparison, I also found that is the total energy released by a hurricane (note, ~99% hurricane energy is released in evaporation, the kinetic is ~1%): Mt. Toba 74kya, VEI 8/M8.8 eruption energy: 1e21-1e22 Joules Global Warming: 7.88e21 Joules/year A hurricane: 1e21 J Hiawatha Crater impact energy: 3e21 J Human energy production 2013: 5.7e20 J/year Mt. Tambora 1815, VEI 7 eruption energy: 1.3e20 J Largest earthquakes 2: 1e19 J Mt. Pinatubo 1991, Krakatoa 1883; VEI 6 eruption energy: 8.3e17 J Mt. St. Helens 1980, VEI 4 eruption energy: 1e17 J World nuclear weapon stockpile yield (estimate 2, extrapolated from USA): ~1e16 J United States nuclear weapon stockpile yield 2020: 1.37e15 J M8 Volcanoes once every million years, but M7 yield > 10x more energy over time: “Analysis of this dataset indicates that eruptions of size M8 and larger have occurred with minimum frequency of 1.4 events/Ma… While the effect of any individual M8 or larger eruption is considerable, the time-averaged impact (i.e., erupted mass*frequency) of the very largest eruptions is small, due to their rarity. The long-term, time-averaged erupted mass flux from magnitude 8 and 9 eruptions is ~10–100 times less than for M7 eruptions; the time-averaged mass eruption rate from M7 eruptions is 9,500 kg s1, whereas for M8 and M9 eruptions it is ~70– 1,000 kg s1. Comparison of the energy release by volcanic eruptions with that due to asteroid impacts suggests that on timescales of <100,000 years, explosive volcanic eruptions are considerably more frequent than impacts of similar energy yield. This has important implications for understanding the risk of extreme events.” - Mason et al2

samatman 6y ago

Regarding Toba, Le Wik has this to say: The erupted mass was, at the very least, 12 times greater than that of the largest volcanic eruption in recent history, the 1815 eruption of Mount Tambora in Indonesia, which caused the 1816 "Year Without a Summer" in the Northern Hemisphere.[8] Toba's erupted mass deposited an ash layer of about 15 centimetres (5.9 in) thick over the whole of South Asia. A blanket of volcanic ash was also deposited over the Indian Ocean, the Arabian Sea, and the South China Sea.[9] Deep-sea cores retrieved from the South China Sea have extended the known reach of the eruption, suggesting that the 2,800 km³ calculation of the erupted mass is a minimum value or even an underestimate.[10] Based on new methods (crystal concentration and exponential), the Lake Toba Caldera possibly erupted as much as 3,200 km³ of ignimbrite and co-ignimbrite. I think its more likely your cursory dismissal which is failing to appreciate the magnitude of this event, than that the person who is actually crunching the numbers is getting it wrong. But what do I know?

pmayrgundter 6y ago
I spent some more time on this and now have a comparison table, with citations in my doc. V8 volcanoes still look more energetic and happen once every million years. @ancientworldnow, I'd note that the figure of 4 Hiroshimas/second is the measure of Global Warming, not of human energy production. Hansen acknowledges this in the linked TED talk from your citation, at about 7 minutes in ("it's about 20 times greater than all the energy used by humanity"). To get a sense of comparison, I also found that is the total energy released by a hurricane (note, ~99% hurricane energy is released in evaporation, the kinetic is ~1%): Mt. Toba 74kya, VEI 8/M8.8 eruption energy: 1e21-1e22 Joules Global Warming: 7.88e21 Joules/year A hurricane: 1e21 J Hiawatha Crater impact energy: 3e21 J Human energy production 2013: 5.7e20 J/year Mt. Tambora 1815, VEI 7 eruption energy: 1.3e20 J Largest earthquakes 2: 1e19 J Mt. Pinatubo 1991, Krakatoa 1883; VEI 6 eruption energy: 8.3e17 J Mt. St. Helens 1980, VEI 4 eruption energy: 1e17 J World nuclear weapon stockpile yield (estimate 2, extrapolated from USA): ~1e16 J United States nuclear weapon stockpile yield 2020: 1.37e15 J M8 Volcanoes once every million years, but M7 yield > 10x more energy over time: “Analysis of this dataset indicates that eruptions of size M8 and larger have occurred with minimum frequency of 1.4 events/Ma… While the effect of any individual M8 or larger eruption is considerable, the time-averaged impact (i.e., erupted mass*frequency) of the very largest eruptions is small, due to their rarity. The long-term, time-averaged erupted mass flux from magnitude 8 and 9 eruptions is ~10–100 times less than for M7 eruptions; the time-averaged mass eruption rate from M7 eruptions is 9,500 kg s1, whereas for M8 and M9 eruptions it is ~70– 1,000 kg s1. Comparison of the energy release by volcanic eruptions with that due to asteroid impacts suggests that on timescales of <100,000 years, explosive volcanic eruptions are considerably more frequent than impacts of similar energy yield. This has important implications for understanding the risk of extreme events.” - Mason et al2