One factor that seldom gets mentioned when talking about warming in the Arctic is the methane that is released when permafrost melts. That could drastically increase the warming curve.
The average lifetime of a water molecule in the atmosphere is about 9 days, as opposed to a CO2 molecule which is on the order of 20-30 years. But that says nothing about how much of either substance is in the atmosphere, just how fast the level can change.
The CO2 in ice cores (like the O2 and N2) never gets compressed enough to solidify. If you're going to propose that there are spikes in CO2 levels that don't show up in ice cores you need to propose a mechanism for that to happen. Otherwise it's just speculation with no scientific backing.
The thing you're not getting is the physics of water. Humans can do very little to directly change the level of water vapor in the atmosphere. It is strictly limited by air temperature and the availability of water to evaporate into the atmosphere. If you pump more of it into the atmosphere it will quickly precipitate out. In a thought experiment some scientists calculated what would happen if you removed 100% of the water vapor from the atmosphere. They found it would take less than 60 days for it to return to normal. The same would be true if you put 100% humidity in the atmosphere. You can't deny the physics.
The thing you're not getting is that because of the physics of water humans can not significantly affect the level of water vapor in the atmosphere except on a local basis. Any excess of water vapor is quickly precipitated out. The level of water vapor in the atmosphere is strictly controlled by temperature and the availability of water to be evaporated into the atmosphere. In a thought experiment some scientists calculated what would happen if you removed 100% of the water vapor from the atmosphere. It took less than 60 days for the level to return to normal. You can't deny the physics of water.
You guys need to give up on that strawman. The CO2 you exhale doesn't matter because it comes from CO2 that was originally in the atmosphere already before it was absorbed by plants that become your food (including the plants that the animals you eat ate).
Around half of the incoming solar radiation is in the visible light range. What doesn't get reflected though gets absorbed and sooner or later released as IR energy.
If we reduce sunlight over a large area we also reduce plant growth in that area because of less of it hitting the leaves. I don't think you can limit the effects of the aerosols to a specific area anyway. If they're small enough to remain in the stratosphere for any length of time they will spread out around the globe as did the sulfate from Pinatubo.
The alternative to fossil fuels is renewable energy. It's not something that is going to happen overnight. I imagine it will happen over the next 30-40 years. With some of the developments in battery technology I've heard about in the past couple of years it looks like battery powered cars will have a 500 mile range in 5-10 years. The cost of solar PV is down to about $1 per kilowatt and getting competitive with coal. The change to renewable energy is happening and we can either be a leader or a follower. Being a leader is usually more profitable.
For thousands of years since the end of the last glaciation around 10,000 years ago the CO2 level in the atmosphere hovered around 280 ppmv. Every year, tracking the seasons, the level fluctuated about 10 ppmv going down as plants grew in the northern hemisphere spring/summer and going back up as stuff decayed in the northern hemisphere autumn/winter. It's all part of the carbon cycle which holds a balance of carbon between the atmosphere, hydrosphere and biosphere (with the geosphere playing a minor role). The carbon in fossil fuels had been sequestered from the carbon cycle for many millions of years but now we are releasing it back into the carbon cycle so a new balance is being created with more carbon in all of the "-spheres". It's quite clear that the increase of carbon in the carbon cycle is due to human activities releasing the fossil carbon.
To claim that water vapor is an issue or that humans could have any effect on water vapor levels in the atmosphere (except in some local situations) it as silly as those guys who claim the CO2 you exhale is going to become an issue. Continuing to bring it up just shows your ignorance.
The Sun provides the incoming energy. Without the greenhouse gases in the atmosphere blocking some of the outgoing IR radiation the average temperature on the surface of the Earth would be around 0F (-17.7C) instead of 58F.
The quantity of water vapor in the troposphere averages around 1% or 10,000 ppmv as compared to 390 ppmv for CO2 which means there is around 25 times as much water vapor in the atmosphere as there is CO2. So, from the Wikipedia article water vapor is responsible for 36-72% of the greenhouse effect and CO2 is responsible for 9-26% of the greenhouse effect. So water vapor is responsible for 3-4 times as much greenhouse warming as CO2 despite being 25 times more prevalent.
Based on that I would say that CO2 is a more potent GHG than water vapor, there's just enough more water vapor in the atmosphere to have a greater warming effect.
If you removed all greenhouse gases from the atmosphere the oceans would freeze, probably to the equator. That's how big an effect the atmosphere has on oceans.
You could never sustain a 50% increase in albedo. The clouds would quickly precipitate out in the cooling atmosphere.
It's true that the top 10 feet of the oceans hold as much heat energy as the whole atmosphere but there are large exchanges of energy between the two going on all of the time. Mostly through evaporation and precipitation. Increased greenhouse gases lead to increases in downward longwave radiation which adds a bit to the ocean temperature. And where did you get that 0.001C number? Does it have any basis in reality?
Of course the ocean has more heat capacity than the atmosphere. That's why there is a 30-40 year lag in atmospheric temperature relative to to the forcing. But as far as thermodynamics go the atmosphere and oceans (and to a lesser extent the land) are a system that has a balance between them. What happens in one affects the other.
One of the big reasons for the current ice age it thought to be the closing of the Isthmus of Panama 2.5 million years ago cutting off currents between the Mid-Atlantic and Pacific oceans.
Hansen has been at NASA's Goddard Institute for Space Studies since 1981. As far as I'm aware their data and methodologies have always been available. Before this last decade it wasn't online of course. Rigging the AC is a new one on me. Have you got a reference? It's not a crime to have flaws in your calculations, just to not correct them once they are discovered.
I've seen no evidence that James Hansen was politically active until the past 5 or 6 years. As I said, maybe as his career is winding down (he's 70) he decided he had to do what he could for posterity based on his knowledge and prestige.
Who is the Luddite here? The person who thinks new technology in renewable energy can replace most if not all fossil fuel energy or the person who doesn't want change?
Hearing a fanatic explain that we must model our nation to a cross between somalia in the 00s and cambodia in the 70s to prevent a couple degree temperature change is simply not very relevant to me.
Nice bit of hyperbole there. Or is it economic alarmism? You complain about people that think how the climate is now is how it always should be but then turn around and get hysterical at the suggestion of any change in the current economic/energy regime.
I don't care how much water vapor you pump into the atmosphere*, you'll never be able to significantly affect the level in the atmosphere. The physics won't allow it.
I think that is my main concern with current climate research and the fixation on carbon and human causes.
Climate scientists have said the primary cause of the warming for the past 50 years is due to increasing greenhouse gases in the atmosphere. The basics of that are really pretty simple physics. No one has yet presented any strong evidence to counter it. Certain powerful factions perceive that the obvious answer of reducing the use of fossil fuels and transferring energy production to renewable resources is counter to their financial interests much like tobacco companies saw reports of the dangers of smoking tobacco as counter to their interests. It's really all about that simple in the end.
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Interesting post.
One factor that seldom gets mentioned when talking about warming in the Arctic is the methane that is released when permafrost melts. That could drastically increase the warming curve.
Don't get the chemtrail crazies going.
The average lifetime of a water molecule in the atmosphere is about 9 days, as opposed to a CO2 molecule which is on the order of 20-30 years. But that says nothing about how much of either substance is in the atmosphere, just how fast the level can change.
Sorry about the double (and now triple) comment. I thought the first had got lost.
The CO2 in ice cores (like the O2 and N2) never gets compressed enough to solidify. If you're going to propose that there are spikes in CO2 levels that don't show up in ice cores you need to propose a mechanism for that to happen. Otherwise it's just speculation with no scientific backing.
The thing you're not getting is the physics of water. Humans can do very little to directly change the level of water vapor in the atmosphere. It is strictly limited by air temperature and the availability of water to evaporate into the atmosphere. If you pump more of it into the atmosphere it will quickly precipitate out. In a thought experiment some scientists calculated what would happen if you removed 100% of the water vapor from the atmosphere. They found it would take less than 60 days for it to return to normal. The same would be true if you put 100% humidity in the atmosphere. You can't deny the physics.
The thing you're not getting is that because of the physics of water humans can not significantly affect the level of water vapor in the atmosphere except on a local basis. Any excess of water vapor is quickly precipitated out. The level of water vapor in the atmosphere is strictly controlled by temperature and the availability of water to be evaporated into the atmosphere. In a thought experiment some scientists calculated what would happen if you removed 100% of the water vapor from the atmosphere. It took less than 60 days for the level to return to normal. You can't deny the physics of water.
It's not that we can't, it's just that we choose not to to.
Ground level ozone is also hard on plants and other living things.
You guys need to give up on that strawman. The CO2 you exhale doesn't matter because it comes from CO2 that was originally in the atmosphere already before it was absorbed by plants that become your food (including the plants that the animals you eat ate).
Power can be produced in many ways that don't involve releasing greenhouse gases. It will just take a few decades to make the switch.
Is the fusion technology that's always 20 years away what you're talking about?
Around half of the incoming solar radiation is in the visible light range. What doesn't get reflected though gets absorbed and sooner or later released as IR energy.
If we reduce sunlight over a large area we also reduce plant growth in that area because of less of it hitting the leaves. I don't think you can limit the effects of the aerosols to a specific area anyway. If they're small enough to remain in the stratosphere for any length of time they will spread out around the globe as did the sulfate from Pinatubo.
The alternative to fossil fuels is renewable energy. It's not something that is going to happen overnight. I imagine it will happen over the next 30-40 years. With some of the developments in battery technology I've heard about in the past couple of years it looks like battery powered cars will have a 500 mile range in 5-10 years. The cost of solar PV is down to about $1 per kilowatt and getting competitive with coal. The change to renewable energy is happening and we can either be a leader or a follower. Being a leader is usually more profitable.
For thousands of years since the end of the last glaciation around 10,000 years ago the CO2 level in the atmosphere hovered around 280 ppmv. Every year, tracking the seasons, the level fluctuated about 10 ppmv going down as plants grew in the northern hemisphere spring/summer and going back up as stuff decayed in the northern hemisphere autumn/winter. It's all part of the carbon cycle which holds a balance of carbon between the atmosphere, hydrosphere and biosphere (with the geosphere playing a minor role). The carbon in fossil fuels had been sequestered from the carbon cycle for many millions of years but now we are releasing it back into the carbon cycle so a new balance is being created with more carbon in all of the "-spheres". It's quite clear that the increase of carbon in the carbon cycle is due to human activities releasing the fossil carbon.
To claim that water vapor is an issue or that humans could have any effect on water vapor levels in the atmosphere (except in some local situations) it as silly as those guys who claim the CO2 you exhale is going to become an issue. Continuing to bring it up just shows your ignorance.
The Sun provides the incoming energy. Without the greenhouse gases in the atmosphere blocking some of the outgoing IR radiation the average temperature on the surface of the Earth would be around 0F (-17.7C) instead of 58F.
The quantity of water vapor in the troposphere averages around 1% or 10,000 ppmv as compared to 390 ppmv for CO2 which means there is around 25 times as much water vapor in the atmosphere as there is CO2. So, from the Wikipedia article water vapor is responsible for 36-72% of the greenhouse effect and CO2 is responsible for 9-26% of the greenhouse effect. So water vapor is responsible for 3-4 times as much greenhouse warming as CO2 despite being 25 times more prevalent.
Based on that I would say that CO2 is a more potent GHG than water vapor, there's just enough more water vapor in the atmosphere to have a greater warming effect.
If you removed all greenhouse gases from the atmosphere the oceans would freeze, probably to the equator. That's how big an effect the atmosphere has on oceans.
You could never sustain a 50% increase in albedo. The clouds would quickly precipitate out in the cooling atmosphere.
It's true that the top 10 feet of the oceans hold as much heat energy as the whole atmosphere but there are large exchanges of energy between the two going on all of the time. Mostly through evaporation and precipitation. Increased greenhouse gases lead to increases in downward longwave radiation which adds a bit to the ocean temperature. And where did you get that 0.001C number? Does it have any basis in reality?
Of course the ocean has more heat capacity than the atmosphere. That's why there is a 30-40 year lag in atmospheric temperature relative to to the forcing. But as far as thermodynamics go the atmosphere and oceans (and to a lesser extent the land) are a system that has a balance between them. What happens in one affects the other.
One of the big reasons for the current ice age it thought to be the closing of the Isthmus of Panama 2.5 million years ago cutting off currents between the Mid-Atlantic and Pacific oceans.
Hansen has been at NASA's Goddard Institute for Space Studies since 1981. As far as I'm aware their data and methodologies have always been available. Before this last decade it wasn't online of course. Rigging the AC is a new one on me. Have you got a reference? It's not a crime to have flaws in your calculations, just to not correct them once they are discovered.
I've seen no evidence that James Hansen was politically active until the past 5 or 6 years. As I said, maybe as his career is winding down (he's 70) he decided he had to do what he could for posterity based on his knowledge and prestige.
Who is the Luddite here? The person who thinks new technology in renewable energy can replace most if not all fossil fuel energy or the person who doesn't want change?
Hearing a fanatic explain that we must model our nation to a cross between somalia in the 00s and cambodia in the 70s to prevent a couple degree temperature change is simply not very relevant to me.
Nice bit of hyperbole there. Or is it economic alarmism? You complain about people that think how the climate is now is how it always should be but then turn around and get hysterical at the suggestion of any change in the current economic/energy regime.
I don't care how much water vapor you pump into the atmosphere*, you'll never be able to significantly affect the level in the atmosphere. The physics won't allow it.
*For any practical amount that humans could pump.
I think that is my main concern with current climate research and the fixation on carbon and human causes.
Climate scientists have said the primary cause of the warming for the past 50 years is due to increasing greenhouse gases in the atmosphere. The basics of that are really pretty simple physics. No one has yet presented any strong evidence to counter it. Certain powerful factions perceive that the obvious answer of reducing the use of fossil fuels and transferring energy production to renewable resources is counter to their financial interests much like tobacco companies saw reports of the dangers of smoking tobacco as counter to their interests. It's really all about that simple in the end.
Of course during the Late Eocene the human population including all known branches of the genus homo was exactly zero.