Water vapor is the major greenhouse gas but it's not a concern for global warming because when the relative humidity reaches 100% it precipitates out. The total water vapor in the atmosphere is limited by temperature.
The amount of solar energy that strikes the surface of the planet in one day is over 80 times the amount of energy used by humanity in one year. It's not a problem for now.
Ah, you think they made to projections to provide support for their preconceived notions about global warming, so Hansen could sound all sciency when testifying to Congress.
I fail to see what is inappropriate about a scientist presenting the results of their research to Congress and as an expert in the field opining on the implications and potential responses to it. I doubt Gavin Schmidt would agree with you that the testimony was inappropriate.
You obviously believe the climate science field is populated by charlatans but I just haven't seen any evidence for that point of view. There is the occasional bad actor in science but the idea that so many scientists would conspire to purposely falsify their science is absurd. If nothing else the conspiracy would have to go back 40 or 50 years or more. I can't believe that level of falsification of science could go on for that length of time without it being discovered. Someone among the thousands of scientists from hundreds of countries working for decades would have figured it out by now.
You don't think climate models have been improved since the 1988 model? Wow! Climate models are simulations of the physical processes that affect climate. You don't think in 20 years our understanding of those physical processes has improved? You don't think that refined understanding has been incorporated into the models? Just the orders of magnitude increase in available computing power since then has allowed more detailed calculations and reduced the grid size they use.
I really don't think error bars don't have anything to do with it but I don't have a good counter argument for that and don't have time now to look it up right now.
I never said the accuracy of a model doesn't matter. I'm basically saying that no scenario they use is going to match the reality that happens 100% so you can't predict what will happen, only project what will happen for a particular scenario. I realize the distinction between predict and project is a pretty fine one but I like to use it that way. Anyway, after the future becomes the past you can then test the models against what actually happened to see how well they do compared to reality.
Why would Dr. Schmidt make any comment about government policy when he's writing about the accuracy of Hansen's 1988 model results 20 years later? Testing it against reality. Gavin Schmidt's opinion is that considering the limitations of technology and knowledge at the time it did alright (at least that's my interpretation of what he said).
But why are we arguing over a 1988 model when we could argue over a 2007 model?;)
A lot of people could die if the climate scientists turn out to be right too.
The main bias I detect in the climate science community is for good science. I realize you don't see it that way. Guess we'll have to leave it at that.
They're not really trying to add more water vapor to the atmosphere. They are trying to add more condensation nuclei to help in the formation of clouds. The concentration of condensation nuclei over the open ocean can be pretty low at times inhibiting the formation of clouds.
In an article on climate forcings at Real Climate maybe a year ago they talked a bit about this. They basically said it appears that clouds over all have a slightly positive effect on global warming but the effect isn't large enough to be statistically significant given what we currently know. It's an area of intense study.
The CO2 from volcanoes does count. It's just that there's not enough of it to worry about. On average volcanoes emit about 1-2% as much CO2 as human emissions.
Isn't the reason that Earth's emission spectrum is already saturated at the wavelengths that water vapor absorbs is that there is already enough water vapor in the atmosphere to accomplish that?
But increasing concentrations of GHGs does have an effect even if their absorption spectrum is saturated. Most of the energy absorbed will be reradiated at some point, some of it in wavelengths that can be absorbed again. Increasing the concentration of a GHG effectively reduces the distance between molecules of the gas making reabsorption more likely. In effect it slows the passage of energy from the surface.
If it's done far enough out to sea I'd be surprised if it put that much salt over land areas. The condensation nuclei that cloud particles form around aren't enough to make it salty to the taste. I bet more than 95% of the salt thrown into the air by this would come back to the sea within a 100 mile radius (but that's just speculation on my part so don't ask me for a cite).
You can't leave out the warming effect of clouds at night. Actually they prevent cooling by reflecting IR radiation back at the ground. Ever notice how much colder it gets on a clear night than on a cloudy night (other factors being equal)?
Last I heard the total effect of clouds on global warming is thought to be slightly positive but it's not enough of a difference, given what we currently know, to be statistically significant.
I have a feeling Dr. Hansen cares more about the science he is doing than he does about accumulating wealth. He certainly has the respect of his colleagues and that gives him a certain amount of power in the field.
In 1989 it was an accurate statement to say that 1988 was the warmest year on record globally based on GISS data. The 1930s may have had some warmer years in the CONUS but that covers less than 2% of the surface of the planet.
Can you cite where he said "because global warming is large it is caused by the greenhouse effect"? That statement doesn't make much sense to me.
Regarding the GISS models and scenarios, I hope you realize that climate models don't predict anything. It's impossible to predict the exact levels of greenhouse gases in the future. It's impossible to predict the exact timing and levels of solar cycles ahead of time. It's impossible to predict the exact timing of things like ENSO or the PDO or a major volcanic eruption. Instead the scientists say they project possible outcomes based on plausible scenarios they create based on past and potential future behavior of the phenomena that are inputs to the models. Rather than comparing the output of the models for various scenarios to reality you test the models by seeing how well they do with real data from the past. If a particular scenario happens to closely match the reality that eventuates then maybe you can use that model output for comparison but that's not especially likely to happen.
But in the end the model you are referring to is from 1988. It may have served as a base for the current GISS models but more detailed knowledge about the various interactions in climate and increases in computing power have improved the current versions immensely.
Gavin Schmidt, the author of the RealClimate article you cited concluded at the end of it:
My assessment is that the model results were as consistent with the real world over this period as could possibly be expected and are therefore a useful demonstration of the model’s consistency with the real world. Thus when asked whether any climate model forecasts ahead of time have proven accurate, this comes as close as you get.
I fail to see what is "stupid and biased" about what he said in the Guardian article and I'm not aware of any evidence of bias at the CRU but I guess you figure I'm just drinking a different flavor of koolaid than you are.
What I heard about the CO2 emissions from the eruption of Eyjafjallajokull is that the flights that were canceled would have emitted twice as much CO2 as the eruption was emitting. This eruption isn't nearly big enough to cause any significant global cooling. However when this volcano erupts then another, Katla, located nearby usually erupts as well and it could be a big enough eruption to cause global cooling.
One other factor in the eruption of Pinatubo in the Philippines was that it is located near the equator and had effects in both hemispheres. The Icelandic volcanoes might not have a lot of effect on the Southern Hemisphere regardless of what they do.
When talking about thermometer accuracy in regards to temperature trends the absolute accuracy doesn't matter so much as the repeatable accuracy. In other words the thermometer gives the same reading for a particular temperature all of the time. Then, even if it's not reading the correct absolute temperature it still accurately shows temperature differences.
No, being one of the worlds leading physicists is what has kept him employed for almost 3 decades. Do you think he's getting rich as head of GISS? I'm sure he's pretty comfortable but I doubt if his salary is much over $200,000 a year. Pretty good for a scientist but not in the same ballpark as someone who's truly rich. I think it was the late 1980s when he started testifying to Congress about global warming. So far he's been more right than wrong about what he's said.
Maybe it's Dr. Hansen's research that informs his political activism. Maybe he's concerned about the world we're going to leave his grandchildren and he wants to do something about it.
The reason to act now is that even if we stopped increasing CO2 levels in the atmosphere tomorrow the warming trend would continue for another 50 years or so primarily because of the thermal buffer of the oceans. You don't think controlling CO2 emissions is important but the vast majority of climate scientists studying the issue disagree. Hmm, who am I going to believe.
The bad state of the data as you put it is due to the fact that it's been collected over the years by hundreds or thousands of different entities under various conditions and various amounts of diligence. Until recently at least it was not collected with the intention to use it for global temperature studies. It has nothing to do with anyone who is working with it today.
Jones is entitled to his opinion that his CRU data is better than the GISS data. I'm sure you'd get an argument from the GISS guys about that.
Differences between GISS and CRU can be attributed to differences in their processing algorithms. In the end their answers aren't that much different. When multiple groups independently use their own methods and come up with substantially the same answers that increases your confidence in what they are saying.
Are you sure it was 10,000 a day rather than 10,000 a year? That's more in line with what the WWF claims. There are probably 10's of millions of species but most of them are bacteria. Most of the animal species are insects. Who knows what genetic knowledge we are losing with all of those extinctions?
The guy you're referring to work at the CRU in England, not at GISS in the US. The GISS data is a separate compilation from the CRU although I'm sure they overlap to a large extent.
Do you want to just throw up your hands and say we don't know anything or should we do the best we can with what we've got imperfect as it is?
I knew it wasn't prefect. All I'll say is that it's not an either/or thing with CO2. Pollution is too much of something where you don't want it. It's like salt. You can die from having too little or too much salt in your diet. It's been nearly 20 million years since atmospheric CO2 levels have been as high as they are now. The biosphere is adapted to levels below 300 ppm. Between global warming and ocean acidification I believe we've got too much CO2 now.
I don't see how you're going to control CO2 emissions without some sort of government intervention. Any suggestions? And not controlling CO2 emissions is not an option IMO.
Scientists are people, citizens and they have families. If they see a problem they believe need urgent attention they have as much right as anyone to state their position.
You're welcome. I always strive to be informative.
Exxon-Mobile was cited in the AR4 report. Are they too biased as well? 10,000 species a day sounds pretty hyperbolic to me. Can you provide a reference? I imagine they could have said 100 a day but even that seems pretty extreme. Maybe if you include all microorganisms.
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Water vapor is the major greenhouse gas but it's not a concern for global warming because when the relative humidity reaches 100% it precipitates out. The total water vapor in the atmosphere is limited by temperature.
The amount of solar energy that strikes the surface of the planet in one day is over 80 times the amount of energy used by humanity in one year. It's not a problem for now.
Ah, AC, networkBoy is talking about diesel which is something you can put a match out in without much danger. I wouldn't try it with gasoline though.
Ah, you think they made to projections to provide support for their preconceived notions about global warming, so Hansen could sound all sciency when testifying to Congress.
I fail to see what is inappropriate about a scientist presenting the results of their research to Congress and as an expert in the field opining on the implications and potential responses to it. I doubt Gavin Schmidt would agree with you that the testimony was inappropriate.
You obviously believe the climate science field is populated by charlatans but I just haven't seen any evidence for that point of view. There is the occasional bad actor in science but the idea that so many scientists would conspire to purposely falsify their science is absurd. If nothing else the conspiracy would have to go back 40 or 50 years or more. I can't believe that level of falsification of science could go on for that length of time without it being discovered. Someone among the thousands of scientists from hundreds of countries working for decades would have figured it out by now.
You don't think climate models have been improved since the 1988 model? Wow! Climate models are simulations of the physical processes that affect climate. You don't think in 20 years our understanding of those physical processes has improved? You don't think that refined understanding has been incorporated into the models? Just the orders of magnitude increase in available computing power since then has allowed more detailed calculations and reduced the grid size they use.
I really don't think error bars don't have anything to do with it but I don't have a good counter argument for that and don't have time now to look it up right now.
I never said the accuracy of a model doesn't matter. I'm basically saying that no scenario they use is going to match the reality that happens 100% so you can't predict what will happen, only project what will happen for a particular scenario. I realize the distinction between predict and project is a pretty fine one but I like to use it that way. Anyway, after the future becomes the past you can then test the models against what actually happened to see how well they do compared to reality.
Why would Dr. Schmidt make any comment about government policy when he's writing about the accuracy of Hansen's 1988 model results 20 years later? Testing it against reality. Gavin Schmidt's opinion is that considering the limitations of technology and knowledge at the time it did alright (at least that's my interpretation of what he said).
But why are we arguing over a 1988 model when we could argue over a 2007 model? ;)
A lot of people could die if the climate scientists turn out to be right too.
The main bias I detect in the climate science community is for good science. I realize you don't see it that way. Guess we'll have to leave it at that.
They're not really trying to add more water vapor to the atmosphere. They are trying to add more condensation nuclei to help in the formation of clouds. The concentration of condensation nuclei over the open ocean can be pretty low at times inhibiting the formation of clouds.
It's only 3,000 feet. The salt won't stay up there that long.
In an article on climate forcings at Real Climate maybe a year ago they talked a bit about this. They basically said it appears that clouds over all have a slightly positive effect on global warming but the effect isn't large enough to be statistically significant given what we currently know. It's an area of intense study.
The CO2 from volcanoes does count. It's just that there's not enough of it to worry about. On average volcanoes emit about 1-2% as much CO2 as human emissions.
Isn't the reason that Earth's emission spectrum is already saturated at the wavelengths that water vapor absorbs is that there is already enough water vapor in the atmosphere to accomplish that?
But increasing concentrations of GHGs does have an effect even if their absorption spectrum is saturated. Most of the energy absorbed will be reradiated at some point, some of it in wavelengths that can be absorbed again. Increasing the concentration of a GHG effectively reduces the distance between molecules of the gas making reabsorption more likely. In effect it slows the passage of energy from the surface.
If it's done far enough out to sea I'd be surprised if it put that much salt over land areas. The condensation nuclei that cloud particles form around aren't enough to make it salty to the taste. I bet more than 95% of the salt thrown into the air by this would come back to the sea within a 100 mile radius (but that's just speculation on my part so don't ask me for a cite).
You can't leave out the warming effect of clouds at night. Actually they prevent cooling by reflecting IR radiation back at the ground. Ever notice how much colder it gets on a clear night than on a cloudy night (other factors being equal)?
Last I heard the total effect of clouds on global warming is thought to be slightly positive but it's not enough of a difference, given what we currently know, to be statistically significant.
I have a feeling Dr. Hansen cares more about the science he is doing than he does about accumulating wealth. He certainly has the respect of his colleagues and that gives him a certain amount of power in the field.
In 1989 it was an accurate statement to say that 1988 was the warmest year on record globally based on GISS data. The 1930s may have had some warmer years in the CONUS but that covers less than 2% of the surface of the planet.
Can you cite where he said "because global warming is large it is caused by the greenhouse effect"? That statement doesn't make much sense to me.
Regarding the GISS models and scenarios, I hope you realize that climate models don't predict anything. It's impossible to predict the exact levels of greenhouse gases in the future. It's impossible to predict the exact timing and levels of solar cycles ahead of time. It's impossible to predict the exact timing of things like ENSO or the PDO or a major volcanic eruption. Instead the scientists say they project possible outcomes based on plausible scenarios they create based on past and potential future behavior of the phenomena that are inputs to the models. Rather than comparing the output of the models for various scenarios to reality you test the models by seeing how well they do with real data from the past. If a particular scenario happens to closely match the reality that eventuates then maybe you can use that model output for comparison but that's not especially likely to happen.
But in the end the model you are referring to is from 1988. It may have served as a base for the current GISS models but more detailed knowledge about the various interactions in climate and increases in computing power have improved the current versions immensely.
Gavin Schmidt, the author of the RealClimate article you cited concluded at the end of it:
I fail to see what is "stupid and biased" about what he said in the Guardian article and I'm not aware of any evidence of bias at the CRU but I guess you figure I'm just drinking a different flavor of koolaid than you are.
What I heard about the CO2 emissions from the eruption of Eyjafjallajokull is that the flights that were canceled would have emitted twice as much CO2 as the eruption was emitting. This eruption isn't nearly big enough to cause any significant global cooling. However when this volcano erupts then another, Katla, located nearby usually erupts as well and it could be a big enough eruption to cause global cooling.
One other factor in the eruption of Pinatubo in the Philippines was that it is located near the equator and had effects in both hemispheres. The Icelandic volcanoes might not have a lot of effect on the Southern Hemisphere regardless of what they do.
When talking about thermometer accuracy in regards to temperature trends the absolute accuracy doesn't matter so much as the repeatable accuracy. In other words the thermometer gives the same reading for a particular temperature all of the time. Then, even if it's not reading the correct absolute temperature it still accurately shows temperature differences.
No, being one of the worlds leading physicists is what has kept him employed for almost 3 decades. Do you think he's getting rich as head of GISS? I'm sure he's pretty comfortable but I doubt if his salary is much over $200,000 a year. Pretty good for a scientist but not in the same ballpark as someone who's truly rich. I think it was the late 1980s when he started testifying to Congress about global warming. So far he's been more right than wrong about what he's said.
It won't take a hundred years. It'll be too obvious for most people to ignore within 10-20 years.
Maybe it's Dr. Hansen's research that informs his political activism. Maybe he's concerned about the world we're going to leave his grandchildren and he wants to do something about it.
The reason to act now is that even if we stopped increasing CO2 levels in the atmosphere tomorrow the warming trend would continue for another 50 years or so primarily because of the thermal buffer of the oceans. You don't think controlling CO2 emissions is important but the vast majority of climate scientists studying the issue disagree. Hmm, who am I going to believe.
The bad state of the data as you put it is due to the fact that it's been collected over the years by hundreds or thousands of different entities under various conditions and various amounts of diligence. Until recently at least it was not collected with the intention to use it for global temperature studies. It has nothing to do with anyone who is working with it today.
Jones is entitled to his opinion that his CRU data is better than the GISS data. I'm sure you'd get an argument from the GISS guys about that.
Differences between GISS and CRU can be attributed to differences in their processing algorithms. In the end their answers aren't that much different. When multiple groups independently use their own methods and come up with substantially the same answers that increases your confidence in what they are saying.
Are you sure it was 10,000 a day rather than 10,000 a year? That's more in line with what the WWF claims. There are probably 10's of millions of species but most of them are bacteria. Most of the animal species are insects. Who knows what genetic knowledge we are losing with all of those extinctions?
The guy you're referring to work at the CRU in England, not at GISS in the US. The GISS data is a separate compilation from the CRU although I'm sure they overlap to a large extent.
Do you want to just throw up your hands and say we don't know anything or should we do the best we can with what we've got imperfect as it is?
I knew it wasn't prefect. All I'll say is that it's not an either/or thing with CO2. Pollution is too much of something where you don't want it. It's like salt. You can die from having too little or too much salt in your diet. It's been nearly 20 million years since atmospheric CO2 levels have been as high as they are now. The biosphere is adapted to levels below 300 ppm. Between global warming and ocean acidification I believe we've got too much CO2 now.
I don't see how you're going to control CO2 emissions without some sort of government intervention. Any suggestions? And not controlling CO2 emissions is not an option IMO.
Scientists are people, citizens and they have families. If they see a problem they believe need urgent attention they have as much right as anyone to state their position.
You're welcome. I always strive to be informative.
Exxon-Mobile was cited in the AR4 report. Are they too biased as well? 10,000 species a day sounds pretty hyperbolic to me. Can you provide a reference? I imagine they could have said 100 a day but even that seems pretty extreme. Maybe if you include all microorganisms.