Weather Effects From Eruption

[leilanidude]

quote:

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Originally posted by TomK

Nothing at all to do with the loss of rainforest.

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Sure it does. Just like it has done in Brazil with the loss of large portions of the Amazon forest. Trees provide shade/cooling, etc.

https://sciencing.com/deforestation-affe...23869.html

"Deforestation, the depletion of forests and other wild flora in woodlands, has significant effects on the weather. These range from local distortions to contributions to global climate change. Deforestation removes the ability of the forest to sequester carbon, absorb sunlight, process water and block the wind."

[Jeremy Lutes]

I have only one data point on recent rain acidity. Couple of weeks ago my girlfriend measured the pH of the rain one evening. It was roughly 4.5, so not very acidic, but I think this was during a time of normal tradewinds activity, FWIW.

I think that if local deforestation is having any effect on weather patterns, it is likely dwarfed by the more direct effects of volcanic activity. The pyrocumulous clouds forming directly over the vent, plus the massive cloud formations spurred by the ocean entry would seem to bear this out.

And I do have a theory as to why we're not seeing more acidic rain, but it's long-winded, and I am not a climatologist

[MarkD]

Loss of rainforest debate--effects on Puna.

"Deforestation, the depletion of forests and other wild flora in woodlands, has significant effects on the weather........Just like it has done in Brazil"

- - -

Deforestation in Brazil is much different from what has happened here:

1) Puna lost several square miles of forest to lava; Brazil has cut down (for agriculture) many thousands of square miles.

2) The deforested land is Brazil is almost all located far inland, distant from ocean. The ocean abutting our island much affects our weather (and climate). Does not seem there is evidence that our loss of forest to lava is affecting weather (or climate).

[Jeremy Lutes]

This seems as appropriate a place as any to post this:

Inspired by the USGS recent estimate of the effusion rate of the new fissure system at ~ 100 cubic meters per second, I thought it would be interesting to try and get a handle on how much energy was being dumped into lower Puna. Someone check my math !

given: Effusion rate ~ 100m^3/s (volume per unit time)
given: Density of 3 g/cm^3 (mass per unit volume)

<< convert effusion rate volume to mass >>
100m^3/s is equivalent to 100x10^6 cm^3/s
now multiply volume by density
(100x10^6 cm^3/s) * (3 g/cm^3) = 300x10^6 g/s

given: initial temp of ~ 1200 degC, final temp of ~ 25 degC
given: Specific heat capacity ~ 0.84 J/g K (energy per unit mass per degree temp change)

<< find delta-T for lava cooled to ambient >>
1200degC - 25degC = 1175degC

<< find energy released from temperature change >>
(300x10^6 g/s) * (1175 degC) * (0.84 J/g K) = 296.1x10^9 joules

1 joule is equal to 1 watt-second, so:

296.1x10^9 watt-seconds

Thats 296 GW !!!

It would take almost 7800 PGV plants to produce that amount of power. All of the nuclear power facilities in the US combined produce only about 1/3 of that power.

[KeaauRich]

"someone check my math" he says... <poof goes my head...>

[TomK]

Jeremy - looks correct to me although it's simpler if you just stick to SI units.

E = M * C * <delta>T

Where E = energy, M = mass, C = specific heat of lava, <delta>T = change in temperature (Kelvins).

E = (100 x 3000) * 840 * 1175

E = 296 GW

Nice one!

[terracore]

Bonus Question: Is Hell exothermic (gives off heat) or Endothermic (absorbs heat)?

Most of the students wrote proofs of their beliefs using Boyle's Law, (gas cools off when it expands and heats up when it is compressed) or some variant. One student, however, wrote the following:

"First, we need to know how the mass of Hell is changing in time. So we need to know the rate that souls are moving into Hell and the rate they are leaving. I think that we can safely assume that once a soul gets to Hell, it will not leave. Therefore, no souls are leaving. As for how many souls are entering Hell, let's look at the different religions that exist in the world today. Some of these religions state that if you are not a member of their religion, you will go to Hell. Since there are more than one of these religions and since people do not belong to more than one religion, we can project that all souls go to Hell. With birth and death rates as they are, we can expect the number of souls in Hell to increase exponentially.

Now, we look at the rate of change of the volume in Hell because Boyle's Law states that in order for the temperature and pressure in Hell to stay the same, the volume of Hell has to expand as souls are added. This gives two possibilities:

If Hell is expanding at a slower rate than the rate at which souls enter Hell, then the temperature and pressure in Hell will increase until all Hell breaks loose.
Of course, if Hell is expanding at a rate faster than the increase of souls in Hell, then the temperature and pressure will drop until Hell freezes over.

So which is it? If we accept the postulate given to me by Teresa Banyan during my Freshman year, "...that it will be a cold day in Hell before I sleep with you." and take into account the fact that I still have not succeeded in having sexual relations with her, then, #2 cannot be true, and thus I am sure that Hell is exothermic and will not freeze."


ETA: https://www-users.cs.york.ac.uk/susan/joke/exoendo.htm

[Jeremy Lutes]

TomK - thanks ! My physics is horribly rusty, but I can usually get there in the end.

terracore - Hah ! Brilliant ! Thanks for the laugh [:p]

[geochem]

Jeremy, Tom,
One small correction: you forgot the heat of crystallization of the basalt minerals - computed at another 13.5 GW...

[bluesboy]

I've personally witnessed blue skies along the southeast corner of the island, with the plumes from the ocean entry and fissure 8 generating their own clouds and rain from those clouds. Living in Mtn View, it seems like that pattern has reached up here, to a lesser extent. I would expect more sunny days in June, but it has been kinda rainy. Although it was really rainy earlier this year, before the eruption started.

I took a trip up to Waimea yesterday, and it was voggy up there. The eruption certainly impact the entire island. It will be interesting to see how a sustained Mauna Loa eruption could impact us, although I think it may have less impact that a Kilauea eruption, since it is more 'downwind' than Kilauea is.