It is literally seeping out of the melting permafrost so there should be no shortage. Here is a fun video of someone setting the air on fire after poking a hole in the ice: http://www.youtube.com/watch?v...
In general, we should expect less rainfall at lower latitudes and more rainfall at higher latitudes. Canada will get wetter while California gets drier.
It takes a long time for the system to reach equilibrium. There is quite a bit of inertia because of the oceans which can absorb massive amounts of energy. The CO2 increases of the 80's are not likely responsible for the warming of the 80's. Rather it would be prior CO2 increases that caused the warming of the 80's.
"The prevailing theory is that the Younger Dryas was caused by significant reduction or shutdown of the North Atlantic "Conveyor", which circulates warm tropical waters northward, in response to a sudden influx of fresh water from Lake Agassiz and deglaciation in North America. Geological evidence for such an event is thus far lacking. The global climate would then have become locked into the new state until freezing removed the fresh water "lid" from the north Atlantic Ocean. An alternative theory suggests instead that the jet stream shifted northward in response to the changing topographic forcing of the melting North American ice sheet, bringing more rain to the North Atlantic which freshened the ocean surface enough to slow the thermohaline circulation. There is also some evidence that a solar flare may have been responsible for the megafaunal extinction, though it cannot explain the apparent variability in the extinction across all continents." - http://en.wikipedia.org/wiki/Y...
The answer (global warming) can be found in this recent paper (among others) whose results emphasize "the oceans' role as Earth's primary energy store. Correlation of trends in total system energy (TE time integrated TOA) against trends in OHC suggests that for most models the ocean becomes the dominant term in the planetary energy budget on a timescale of about 12 months." http://iopscience.iop.org/1748...
FTFA: "The collapse of large parts of the ice sheet in West Antarctica appears to have begun and is almost certainly unstoppable, with global warming accelerating the pace of the disintegration, two groups of scientists reported Monday."
we have no idea what might happen. Its possible that the ice may reform there or somewhere else
Actually, thanks to science we do have an idea!
"at this point, a decrease in the melt rate back to earlier levels would be “too little, too late to stabilize the ice sheet,” said Ian Joughin, a glaciologist at the University of Washington and lead author of the new paper in Science. “There’s no stabilization mechanism.” The basic problem is that much of the West Antarctic ice sheet sits below sea level in a kind of bowl-shaped depression the earth. As Dr. Mercer outlined in 1978, once the part of the ice sheet sitting on the rim of the bowl melts and the ice retreats into deeper water, it becomes unstable and highly vulnerable to further melting."
Why do you presume to know more than the scientists that study this? A skeptical mind might suppose that the scientists are considering something that you are failing to see. Perhaps the WAIS acts as a buttress that supports inland ice? Remove the buttress and the inland ice will flow? Just a guess, but probably more accurate than assuming that the experts overlooked something obvious.
So which is it? You said "we don't swing wildly from one temperature to another". But you also liken the wild swing from glacial to interglacial to the pendulum on a clock. Meaning we see wild swings all the time? It is really unclear what you are trying to argue.
Well, I was referring to observed feedbacks. We haven't observed changes in cloud cover, but you are right that if this did occur it would act as a positive or negative feedback. Clouds emit infrared radiation back to the surface, and so exert a warming effect. They also reflect sunlight and emit infrared radiation to space, and so exert a cooling effect. So if global warming does change cloud cover, the net effect could be warming or cooling depending on the type and altitude of the cloud.
There is quite a bit of inertia, but right now we are accumulating energy at a rate of 4 Hiroshima bombs per second. (http://www.skepticalscience.com/4-Hiroshima-bombs-worth-of-heat-per-second.html). That has started to nudge us out of the relative stability we have seen for the last 10,000 years. It was a relatively minor forcing that moved us from the last glacial period to the current inter-glacial - which is surely a wild swing from one temperature to another.
This fluctuation in tropospheric temperatures is a behavour that we see emerge in the models as well. What you have to remember is that when you measure tropospheric temperatures you are measuring one small part of the system. Tropospheric temperatures have increased by about 0.2C over the last 15 years ( http://www.woodfortrees.org/pl... ). That is not insignificant but is somewhat slower than the previous decade. Meanwhile the ocean has also continued to accumulate energy.
Ultimately what we find is that fluctuations in tropospheric temperatures are the result of energy moving about within the system (from troposphere to ocean and back), rather than a violation of thermodynamics. So as you can see, energy fluctuations in one part of the system cannot contradict feedbacks.
In fact, we have observed many feedbacks first hand. For instance, atmospheric water vapour has increased by about 4% since the 70's. The more warming, the more water vapour the atmosphere will hold. Water vapour is a powerful greenhouse gas. Likewise, on average summertime polar ice is declining due to warming. The less summertime ice we have the less solar energy will be reflected back into space. This is another feedback that we can measure and have observed.
The question isn't whether "CO2 causes warming" but whether a change from 290 to 330 ppm in the troposphere can be the cause of a measurable change in the heat content of troposphere.
Well, we blew past 330 ppm in the 1960's and are now at 400 ppm. That causes a direct forcing (not including feedbacks) of 5.35*ln(400/280)W/m^2 or about 1.9 W/m^2. For comparison, the output from the sun fluctuates by as much as 1 W/m^2 every 11 years. CO2 is now causing a forcing that is double the increase in solar forcing - but the CO2 forcing is constant while the solar forcing only peaks once every 11 years.
I'm curious whether your undergraduate text explains why increased CO2 concentration in the stratosphere causes the stratosphere to loose heat.
Here is what the Max Planck Institute for Chemistry says: "Greenhouse gases (CO2, O3, CFC) absorb infra-red radiation from the surface of the Earth and trap the heat in the troposphere. If this absorption is really strong, the greenhouse gas blocks most of the outgoing infra-red radiation close to the Earth's surface. This means that only a small amount of outgoing infra-red radiation reaches carbon dioxide in the upper troposphere and the lower stratosphere. On the other hand, carbon dioxide emits heat radiation, which is lost from the stratosphere into space. In the stratosphere, this emission of heat becomes larger than the energy received from below by absorption and, as a result, there is a net energy loss from the stratosphere and a resulting cooling." - http://www.atmosphere.mpg.de/e...
Curiously, your friend believes "The earth's climate is too complex to accurately model and predict.", but is certain that "There are feedback mechanisms that mute the severity of CO2-induced warming."
This seems like wishful thinking. If we really don't have a good handle on the severity of global warming then it is just as likely that the impacts will be much greater than anticipated.
Regarding the costs of mitigating, all published economists agree that it is cheaper to mitigate than to accept the impacts of climate change, and the sooner we start mitigating the cheaper it will be.
The point is that we know that drought is exacerbated by global warming in lower latitudes. We also know that droughts happen even without climate change. How would you prove that this one or that one wouldn't have happened even without climate change? How would you prove that this smoker or that smoker wouldn't have lung cancer even without smoking? Are you looking for a reasonable burden of proof?
You will not get far with that proposal because you are then redistributing money from the rich to the poor. That is a liberal agenda that goes beyond the original purpose of the tax. A tax at port of entry is already applied according to usage. I agree that you would have to manage the tax closely, but that could be done.
Slashdot Mirror
It is literally seeping out of the melting permafrost so there should be no shortage. Here is a fun video of someone setting the air on fire after poking a hole in the ice: http://www.youtube.com/watch?v...
In general, we should expect less rainfall at lower latitudes and more rainfall at higher latitudes. Canada will get wetter while California gets drier.
During the Last Glacial Maximum (only ~23,000 years ago), sea level was 400 feet lower than it is today.
Good thing they didn't have any coastal cities 23,000 years ago. That would have sucked.
In fact, every species that's alive today has managed to survive dozens of glacial advances and glacial retreats
What about the species that aren't alive today? How did they do?
It takes a long time for the system to reach equilibrium. There is quite a bit of inertia because of the oceans which can absorb massive amounts of energy. The CO2 increases of the 80's are not likely responsible for the warming of the 80's. Rather it would be prior CO2 increases that caused the warming of the 80's.
http://www.youtube.com/watch?v... - The truth is out there! Don't let the loony left tell you otherwise!
"The prevailing theory is that the Younger Dryas was caused by significant reduction or shutdown of the North Atlantic "Conveyor", which circulates warm tropical waters northward, in response to a sudden influx of fresh water from Lake Agassiz and deglaciation in North America. Geological evidence for such an event is thus far lacking. The global climate would then have become locked into the new state until freezing removed the fresh water "lid" from the north Atlantic Ocean. An alternative theory suggests instead that the jet stream shifted northward in response to the changing topographic forcing of the melting North American ice sheet, bringing more rain to the North Atlantic which freshened the ocean surface enough to slow the thermohaline circulation. There is also some evidence that a solar flare may have been responsible for the megafaunal extinction, though it cannot explain the apparent variability in the extinction across all continents." - http://en.wikipedia.org/wiki/Y...
:) This needs to be modded up :)
The answer (global warming) can be found in this recent paper (among others) whose results emphasize "the oceans' role as Earth's primary energy store. Correlation of trends in total system energy (TE time integrated TOA) against trends in OHC suggests that for most models the ocean becomes the dominant term in the planetary energy budget on a timescale of about 12 months." http://iopscience.iop.org/1748...
Out of curiosity, what do you suppose 'Layzej' means? I'm curious how that could be 'not unironic'...
FTFA: "The collapse of large parts of the ice sheet in West Antarctica appears to have begun and is almost certainly unstoppable, with global warming accelerating the pace of the disintegration, two groups of scientists reported Monday."
we have no idea what might happen. Its possible that the ice may reform there or somewhere else
Actually, thanks to science we do have an idea!
"at this point, a decrease in the melt rate back to earlier levels would be “too little, too late to stabilize the ice sheet,” said Ian Joughin, a glaciologist at the University of Washington and lead author of the new paper in Science. “There’s no stabilization mechanism.” The basic problem is that much of the West Antarctic ice sheet sits below sea level in a kind of bowl-shaped depression the earth. As Dr. Mercer outlined in 1978, once the part of the ice sheet sitting on the rim of the bowl melts and the ice retreats into deeper water, it becomes unstable and highly vulnerable to further melting."
What do you suppose is heating the ocean?
Why do you presume to know more than the scientists that study this? A skeptical mind might suppose that the scientists are considering something that you are failing to see. Perhaps the WAIS acts as a buttress that supports inland ice? Remove the buttress and the inland ice will flow? Just a guess, but probably more accurate than assuming that the experts overlooked something obvious.
Sure thing: http://en.wikipedia.org/wiki/R...
Wow.
So which is it? You said "we don't swing wildly from one temperature to another". But you also liken the wild swing from glacial to interglacial to the pendulum on a clock. Meaning we see wild swings all the time? It is really unclear what you are trying to argue.
Can you cite one?
The transition from glacial to inter-glacial is evidence of a massive positive feedback.
Well, I was referring to observed feedbacks. We haven't observed changes in cloud cover, but you are right that if this did occur it would act as a positive or negative feedback. Clouds emit infrared radiation back to the surface, and so exert a warming effect. They also reflect sunlight and emit infrared radiation to space, and so exert a cooling effect. So if global warming does change cloud cover, the net effect could be warming or cooling depending on the type and altitude of the cloud.
There is quite a bit of inertia, but right now we are accumulating energy at a rate of 4 Hiroshima bombs per second. (http://www.skepticalscience.com/4-Hiroshima-bombs-worth-of-heat-per-second.html). That has started to nudge us out of the relative stability we have seen for the last 10,000 years. It was a relatively minor forcing that moved us from the last glacial period to the current inter-glacial - which is surely a wild swing from one temperature to another.
This fluctuation in tropospheric temperatures is a behavour that we see emerge in the models as well. What you have to remember is that when you measure tropospheric temperatures you are measuring one small part of the system. Tropospheric temperatures have increased by about 0.2C over the last 15 years ( http://www.woodfortrees.org/pl... ). That is not insignificant but is somewhat slower than the previous decade. Meanwhile the ocean has also continued to accumulate energy.
Ultimately what we find is that fluctuations in tropospheric temperatures are the result of energy moving about within the system (from troposphere to ocean and back), rather than a violation of thermodynamics. So as you can see, energy fluctuations in one part of the system cannot contradict feedbacks.
In fact, we have observed many feedbacks first hand. For instance, atmospheric water vapour has increased by about 4% since the 70's. The more warming, the more water vapour the atmosphere will hold. Water vapour is a powerful greenhouse gas. Likewise, on average summertime polar ice is declining due to warming. The less summertime ice we have the less solar energy will be reflected back into space. This is another feedback that we can measure and have observed.
The question isn't whether "CO2 causes warming" but whether a change from 290 to 330 ppm in the troposphere can be the cause of a measurable change in the heat content of troposphere.
Well, we blew past 330 ppm in the 1960's and are now at 400 ppm. That causes a direct forcing (not including feedbacks) of 5.35*ln(400/280)W/m^2 or about 1.9 W/m^2. For comparison, the output from the sun fluctuates by as much as 1 W/m^2 every 11 years. CO2 is now causing a forcing that is double the increase in solar forcing - but the CO2 forcing is constant while the solar forcing only peaks once every 11 years.
I'm curious whether your undergraduate text explains why increased CO2 concentration in the stratosphere causes the stratosphere to loose heat.
Here is what the Max Planck Institute for Chemistry says: "Greenhouse gases (CO2, O3, CFC) absorb infra-red radiation from the surface of the Earth and trap the heat in the troposphere. If this absorption is really strong, the greenhouse gas blocks most of the outgoing infra-red radiation close to the Earth's surface. This means that only a small amount of outgoing infra-red radiation reaches carbon dioxide in the upper troposphere and the lower stratosphere. On the other hand, carbon dioxide emits heat radiation, which is lost from the stratosphere into space. In the stratosphere, this emission of heat becomes larger than the energy received from below by absorption and, as a result, there is a net energy loss from the stratosphere and a resulting cooling." - http://www.atmosphere.mpg.de/e...
Curiously, your friend believes "The earth's climate is too complex to accurately model and predict.", but is certain that "There are feedback mechanisms that mute the severity of CO2-induced warming."
This seems like wishful thinking. If we really don't have a good handle on the severity of global warming then it is just as likely that the impacts will be much greater than anticipated.
Regarding the costs of mitigating, all published economists agree that it is cheaper to mitigate than to accept the impacts of climate change, and the sooner we start mitigating the cheaper it will be.
The point is that we know that drought is exacerbated by global warming in lower latitudes. We also know that droughts happen even without climate change. How would you prove that this one or that one wouldn't have happened even without climate change? How would you prove that this smoker or that smoker wouldn't have lung cancer even without smoking? Are you looking for a reasonable burden of proof?
You will not get far with that proposal because you are then redistributing money from the rich to the poor. That is a liberal agenda that goes beyond the original purpose of the tax. A tax at port of entry is already applied according to usage. I agree that you would have to manage the tax closely, but that could be done.