I read something about this recently. Clouds indeed reflect sunlight, but they also trap IR radiation from the surface that otherwise would make it out in to space. The clouds also radiate IR into space, but the higher the clouds, the cooler they are, and the less they radiate. Apparently, for very high clouds, the net effect is heating (i.e. the heat trapping effect is larger than light reflecting effect), while for low clouds, the net effect is cooling.
Not an expert, but my understanding is, yes, clouds cool the earth during the day, compared to no clouds, and they warm it at night. But on net water vapor is a greenhouse gas: it holds onto heat, and it absorbs the wavelengths emitted by the earth disproportionately more than those emitted by the sun, so it keeps more heat in than out.
Water vapor accounts for 70% of the greenhouse effect. It's actually the most potent greenhouse gas in the Earth's atmosphere. Increasing a mere 5% is a really, really big deal.
How much light clouds reflect depends on the particulate pollution is in the air, there’s an interesting phenomenon that doesn’t get talked about very often called Global dimming. https://en.m.wikipedia.org/wiki/Global_dimming
> Clouds within a mile or so of Earth’s surface tend to cool more than they warm. These low, thicker clouds mostly reflect the Sun’s heat. This cools Earth’s surface.
> Clouds high up in the atmosphere have the opposite effect: They tend to warm Earth more than they cool. High, thin clouds trap some of the Sun’s heat. This warms Earth’s surface.
Isn't it a consensus view now that life on earth is statistically more likely to be a product of panspermia than to have independently evolved, thus technically all life on earth including ourselves is alien? (ie. we are the terraforming reptilians...)
So, my take after reading the article is that all the climate change alarmists and all the climate change deniers just had any arguments for why they are right and the other side wrong blown wide open by a pesky volcano that will change the atmosphere in a way nobody had predicted the day before that volcano erupted.
No. That's not what is happening here - we have made the planet more vulnerable to these events by changing the climate otherwise this eruption would have simply been situation normal. Now it is going to cause us problems.
The alarmists in this case are on the right side of history.
Eruptions on that scale have always caused major shifts in global weather and sometimes resulted in unexpected catastrophes far, far away from the eruption.
I doubt it. The alarmists have never been right about global warming. Even back when it was called global cooling. Nor about peak oil. Nor about the ozone. Nor about HIV. Nor about covid. I really can't remember anything the alarmists have been right about. Has drought wiped out california yet? I remember the alarmists were really worried about california a few years ago. Is new orleans underwater yet? I remember how concerned the alarmists were about new orleans. The levee is holding?
Also, the article is from 2022. The eruption occurred in jan 2022. And they only expected it to affect the climate for 'the months to come'. So, no reason to be alarmed now more than 1.5 years after the eruption.
What do you mean? In some of those cases (Ozone, HIV, covid), people did a lot of work to deal with the problem, and succeeded. Are you saying the alarm was not warranted? We should have continued using CFCs? not worked on ARVs? Ignored the problem and not worked on vaccines? What exactly is your point? Because the sky didn't fall, we should not have cared a priori?
But if it had been a different type of eruption, it could have caused worldwide cooling, right? Isn’t that what happened after Mt. Pinatubo?
Are eruptions predominantly warming events or cooling events or pretty evenly split? I suppose the vast majority probably only have local effects, but of the big ones, I feel like this is the first one I’ve heard of that’s caused temperatures to rise?
Most eruptions cause cooling via release of SO2, and some very short term local cooling with ash.
This eruption released a lot of water vapor because it was underwater, and water vapour is actually a very potent greenhouse gas.
So in general, volcanoes on land will cause cooling. I don't know if you can generalise underwater volcanoes the same way, it probably depends on how deep they are.
This is potentially a stupid question, but I will ask... Water vapor is a potent greenhouse.
The H2 crowd markets their products/tech as "zero emissions." Why does hydrogen-as-a-fuel seemingly get a pass on water vapor emissions, despite them being a significant greenhouse gas?
Because water vapor is condensable. It has a very short half life in the atmosphere. Depending what source you find, it ranges from 4 to 9 days. That's days. CO2 has a half life of more than one century.
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[ 3.3 ms ] story [ 26.5 ms ] thread> Clouds high up in the atmosphere have the opposite effect: They tend to warm Earth more than they cool. High, thin clouds trap some of the Sun’s heat. This warms Earth’s surface.
https://climatekids.nasa.gov/cloud-climate/
We live in interesting times indeed.
The alarmists in this case are on the right side of history.
[https://www.earthdata.nasa.gov/learn/sensing-our-planet/volc...]
Also, the article is from 2022. The eruption occurred in jan 2022. And they only expected it to affect the climate for 'the months to come'. So, no reason to be alarmed now more than 1.5 years after the eruption.
Are eruptions predominantly warming events or cooling events or pretty evenly split? I suppose the vast majority probably only have local effects, but of the big ones, I feel like this is the first one I’ve heard of that’s caused temperatures to rise?
This eruption released a lot of water vapor because it was underwater, and water vapour is actually a very potent greenhouse gas.
So in general, volcanoes on land will cause cooling. I don't know if you can generalise underwater volcanoes the same way, it probably depends on how deep they are.
The main cooling gas appears to be sulfur dioxide.
The H2 crowd markets their products/tech as "zero emissions." Why does hydrogen-as-a-fuel seemingly get a pass on water vapor emissions, despite them being a significant greenhouse gas?