Global Warming

[DaveS]

The figure you scanned is from a paper by Marsh and Svensmark:

Marsh, N., and H. Svensmark (2003), Galactic cosmic ray and El Niño–Southern Oscillation trends in International Satellite Cloud Climatology Project D2 low-cloud properties, J. Geophys. Res., 108(D6), 4195, doi:10.1029/2001JD001264.

While the low cloud correlation appears to be quite good, there are several issues that have been brought up with the analysis they performed (which I doubt Svensmark included in his book). The first is the cloud data set they used. It is from a satellite instrument called ISCCP, which obviously views clouds from above. As such it can only resolve the low clouds that they claim are correlated when they are not obscured by higher clouds. This leads to biased sampling, it is very hard to say that there has been an actual change in the low clouds, or if there has been a change in the higher clouds allowing ISCCP to see the low clouds more frequently. The second issue is that Marsh and Svensmark applied a 'correction' to the ISCCP data, that is necessary to make their correlation work. While correcting satellite data is not unheard of and is often necessary to account for changes in instrument response etc, it is generally performed by the satellite science team and not the data end user. It is awfully suspicious that Marsh and Svensmark took it on themselves to make a correction to satellite data that NOAA didn't deem necessary.

Have you got proof of that please? I am most certainly not accusing you of lying but I would like to see your source to analyse it for myself.

Finally, and on a more fundamental level, if GCR are responsible for the current warming, why is there no decreasing trend in GCR over the past 5 decades using the very same data svensmark cites:
[URL]http://www.ngdc.noaa.gov/stp/SOLAR/C...YS/cosmic.html[/URL]

I am currently trying to find a graph which contains both cosmic ray levels and temperature, I think this would be better to analyse this claim in more detail. The book in question has such data over a wider timescale showing correlation but not in any great detail over the last couple of years. If I may though the initial thing I noticed in the graph was that the cosmic ray flux was quite reduced from around 1965-75. This coincides curiously with the time when temperatures were actually cooler which gave rise to the global cooling scare. It would seem at least that GCRs played a part in this.


---- To go back to CO2 GW Theory briefly - what caused the regular CO2 rises and falls with temperature in the past? It is the regularity that I'm most interested in. Also, I am concerned about how CO2 can fall that abruptly with temperature. The theory states that increased CO2 levels will cause an increased greenhouse effect which will in turn increase temperatures. However, as CO2 increases this heat will also be continually reflected back to Earth which will almost create an exponential effect; basically it is irreversible (if you listen to the News that is). What then could have caused such sharp decreases in CO2 in the past and also where did the CO2 come from in the first place?

 

[chaim]

Have you got proof of that please? I am most certainly not accusing you of lying but I would like to see your source to analyse it for myself.

Marsh and Svensmark discuss the correction they made to ISCCP data in the paper I referenced above. It is straight from the horses mouth. The issue with cloud cover is common sense, the ISCCP instrument is an IR instrument and cannot see through clouds therefor to see low level clouds, you can't have middle or upper level clouds. This leads to an inherent sampling bias. The specific isue with the ISCCP adjustment were covered by Gavin Schmidt at the AGU meeting late last year. This is not something to get too hung up on, I do believe there maybe a correlation between GCR and low level clouds. However I also think there needs to be considerably more research and it has been dreadfully oversold. I also don't thik it is what is forcing the climate.

I am currently trying to find a graph which contains both cosmic ray levels and temperature, I think this would be better to analyse this claim in more detail. The book in question has such data over a wider timescale showing correlation but not in any great detail over the last couple of years. If I may though the initial thing I noticed in the graph was that the cosmic ray flux was quite reduced from around 1965-75. This coincides curiously with the time when temperatures were actually cooler which gave rise to the global cooling scare. It would seem at least that GCRs played a part in this.

I provided both GCR data and temperature data plot a couple of posts back as well as a link to climax data that Svensamrk himself used. There is no correlation. It not that unsurprising that Svensmark did not include this data in his book as it unhinges his entire theory. It maybe that previous warmings were in some way connected to GCR, but it quite clear form this data that the current warming is not. 1965-1975 corresponds to a solar minima, so it is not surprising that there is a GCR minima at the same time. However we don't see a significant decrease in temperature. Secondly if this was a robust mechanism, why is there no correlation between T and later solar/GCR minima? You can't just pull one point and claim that there is correlation when there is no correlation for the 4 other solar minima.

---- To go back to CO2 GW Theory briefly - what caused the regular CO2 rises and falls with temperature in the past? It is the regularity that I'm most interested in. Also, I am concerned about how CO2 can fall that abruptly with temperature. The theory states that increased CO2 levels will cause an increased greenhouse effect which will in turn increase temperatures. However, as CO2 increases this heat will also be continually reflected back to Earth which will almost create an exponential effect; basically it is irreversible (if you listen to the News that is). What then could have caused such sharp decreases in CO2 in the past and also where did the CO2 come from in the first place?

The previous climate changes we see (every 100,000 years) are due to orbital dynamics, primarily the Milankovitch cycle. You will also notice that CO2 lags behind temperature, it is not the initial cause of the warming, orbital dynamics and hence changes in total solar irradiance are the initial cause. CO2 then responds to this forcing, this likely due to changes in ocean temperature (which consistently has an overturning period of ~1000 years) and associated carbon cycle changes which reduce the oceans ability to remove Co2 from the atmosphere. Secondly the solubility of CO2 in water goes down with increasing temperature. As for how the co2 is removed when TSI goes down, I don't know, I will leave that up to you to find out.

I do wonder why you are seemingly ignoring an enormous body of research to concentrate on the research of just one scholar, who's theory has been rejected b almost every scientific organization on earth? Why is it that you don't seem to believe the national academy of science but you do believe Svensmark?

 

[Greatcloud]

Hate to be a stickler... but increasing the spin of Mars won't increase the gravity...

gravity is a function of mass, not RPM

Yes mass is a big factor in gravity but it is not the only factor. If you have a large spaceship in space and you stop forward motion,what happens ? Without acceleration to hold the crew in place they would float away like Mars's atmosphere up to the bulkheads. A simple spinning of the ship creates gravity and holds the crew in place with artifical gravity.Here is some further information:http://curious.astro.cornell.edu/question.php?number=65

So getting back to Mars, its gravity is 1/3 that of the Earth. This means any added atmosphere would float away into space. The main reason is,that the mass of Mars is almost half of Earth. The rotation of Mars is slightly more then Earth. We can't change Mars's mass but we can change its rotation. Changing its rotation will increase its gravity enough to hold more thinner types of atmosphere like O2,N2 ect. holding air we breathe. The added benefit of increased gravity will allow us more comfortable living on Mars in other ways too.

 

[DaveS]

Marsh and Svensmark discuss the correction they made to ISCCP data in the paper I referenced above. It is straight from the horses mouth. The issue with cloud cover is common sense, the ISCCP instrument is an IR instrument and cannot see through clouds therefor to see low level clouds, you can't have middle or upper level clouds. This leads to an inherent sampling bias. The specific isue with the ISCCP adjustment were covered by Gavin Schmidt at the AGU meeting late last year. This is not something to get too hung up on, I do believe there maybe a correlation between GCR and low level clouds. However I also think there needs to be considerably more research and it has been dreadfully oversold. I also don't thik it is what is forcing the climate.

Fair enough, just wanted to be sure. I think unfortunately most things to do with climate science gets over-sold as it is the science that everyone can see for themselves everyday - I also think that as far as the scientists go it is a destructive cycle as it seems that it is the one who shouts loudest that wins.

I will address the other points tomorrow if I get an opportunity - it is late here and I have yet more revision to do tomorrow!

 

[chaim]

You are kidding right? If not you need to retake physics 1. The centrifugal force is in the opposite direction of gravity, radially out from the center of rotation. Spin a ball on a string around your head - does the force on the string pull towards you or away from you?

Increasing the spin of mars will decrease the effective force of gravity. Stopping Mars from spinning all together would very slightly increase the force of gravity, but no more than the current gravitational force at the Martian poles. For comparison the spin of earth (which is comparable to Mars) changes 'gravitational' force from 9.789m/s2 at the equator to 9.832 at the poles, or about 0.03%.

Yes mass is a big factor in gravity but it is not the only factor. If you have a large spaceship in space and you stop forward motion,what happens ? Without acceleration to hold the crew in place they would float away like Mars's atmosphere up to the bulkheads. A simple spinning of the ship creates gravity and holds the crew in place with artifical gravity.Here is some further information:http://curious.astro.cornell.edu/question.php?number=65

So getting back to Mars, its gravity is 1/3 that of the Earth. This means any added atmosphere would float away into space. The main reason is,that the mass of Mars is almost half of Earth. The rotation of Mars is slightly more then Earth. We can't change Mars's mass but we can change its rotation. Changing its rotation will increase its gravity enough to hold more thinner types of atmosphere like O2,N2 ect. holding air we breathe. The added benefit of increased gravity will allow us more comfortable living on Mars in other ways too.

 

[chaim]

I disagree with you here. It is not those who shout the loudest that win, it is those who follow the scientific method that win. Time after time scientists have come up with 'unpopular' discoveries with political and religious opponents. The ozone hole is a great example of this and an excellent analogy for climate change. There was great opposition to CFCs being the culprit from industry and from many of the same skeptics that are now deriding climate science. However in the end science won out. I am hopeful the same thing will happen with climate change.

Unfortunately Svensmark is an example of a scientist who is trying to scream the loudest. Generally speaking scientists don't issue press releases, and if they do, they stick to what they cover in their science. Svensmark on the other hand immediately issued a press release and went well beyond the conclusions that could be reached based on his research.

Fair enough, just wanted to be sure. I think unfortunately most things to do with climate science gets over-sold as it is the science that everyone can see for themselves everyday - I also think that as far as the scientists go it is a destructive cycle as it seems that it is the one who shouts loudest that wins.

I will address the other points tomorrow if I get an opportunity - it is late here and I have yet more revision to do tomorrow!

 

[Greatcloud]

You are kidding right? If not you need to retake physics 1. The centrifugal force is in the opposite direction of gravity, radially out from the center of rotation. Spin a ball on a string around your head - does the force on the string pull towards you or away from you?

Increasing the spin of mars will decrease the effective force of gravity. Stopping Mars from spinning all together would very slightly increase the force of gravity, but no more than the current gravitational force at the Martian poles. For comparison the spin of earth (which is comparable to Mars) changes 'gravitational' force from 9.789m/s2 at the equator to 9.832 at the poles, or about 0.03%.

Ok I thought about it and you are right on the outside surface of a planet it is the opposite. I was thinking about the inside of a hollow sphere/spaceship.

The main problem with terraforming Mars is still a lack of atmosphere and how to keep it. I suppose we could reduce the spin with nuclear warheads but there would be hardly any effect. Suggestions ? Maybe we should start a thread.

 

[astrios]

Globalwarming is a serious trueth. Icecap melting, record hitting heats, Eil nino phenomenon, coral decadence etc are indicating catastrophic warming is underway. but people must remember that deforestation may be a significant contribution to this effect, besides our Sun can also be a dangerous compliment, which will eventually be a giant red burning all it have created. I am not sure which to blame yet..

Whatever happens, our planet is our face. With the nature being irreversibly changed, we have to consider what we are going to be then. Any catastrophe can be a push into brighter future if we calculate a suitable way to go. I am anticipating a apocaliptic natural event sometime in the near future..

Climate change is only a chapter of the grand drama of Earths caprice.Our human only act to stimulate responses from it, once it make an answer, it will be a fatal one. What about extinction of numerous animal species, and emergence of new viruses? These affect our life more than warming earth to day. As long as we know we have to take care of our environment, nature, animals there will be a way out from destroying ourself with hand of nature, to the future of a more human, sensible, loving society.

 

[Gus2009]

You are kidding right? If not you need to retake physics 1. The centrifugal force is in the opposite direction of gravity, radially out from the center of rotation. Spin a ball on a string around your head - does the force on the string pull towards you or away from you?

Both. The centripetal force goes toward center of rotation. There is a force component directed toward you as spin the ball.

A spinning spaceship section uses centrifugal force to mimic gravity as you said. Perhaps, if the inside of mars coud be turned into a hollow sphere and people were standing on the inside of it the "gravity" would be increased by uping the rotation velocity.

Why or how you would ever do that i have no idea.

 

[us38]

Ok I thought about it and you are right on the outside surface of a planet it is the opposite. I was thinking about the inside of a hollow sphere/spaceship.

The main problem with terraforming Mars is still a lack of atmosphere and how to keep it. I suppose we could reduce the spin with nuclear warheads but there would be hardly any effect. Suggestions ? Maybe we should start a thread.

Reducing spin isn't that easy. Angular momentum is conserved. The only way to slow down the spinning of a planet is to make something else spin.

 

[Greatcloud]

I am correct in thinking that spinning Mars would increase gravity. Do you not see that the molten core inside the planet is what would have added attraction ? So that means we would not go flying off as some have stated , but be pulled down to the ground.The molton core would increase in diameter and the increased diameter or mass would increase gravity. Of course this has a limit.

 

[chaim]

You have to do a little more thinking about this. The radius you use for calculating gravitational attraction is the distance between theoretical point masses. However for a spherically symmetrical object, such as a planet, the center of mass can be taken as a 'point mass'. So making the planet bigger, or moving the mass further from the center does nothing to change the center of mass. In fact if from rotation the planet became more oblate, the r term would increase at the equator and the force of gravity would decrease like r squared.

Never mind the fact that the centripetal acceleration is proportional to the rotation squared so this term would dominate.

I am correct in thinking that spinning Mars would increase gravity. Do you not see that the molten core inside the planet is what would have added attraction ? So that means we would not go flying off as some have stated , but be pulled down to the ground.The molton core would increase in diameter and the increased diameter or mass would increase gravity. Of course this has a limit.

 

[Greatcloud]

And speaking of indices, here are the 2007 to-date ACE values for the storms. ACE for a hurricane season incorporates storm count, intensity and duration and gives a better indication of a season’s activity than storm count alone:
The normal ACE for an Atlantic season is 100.
Dean: 34
Felix: 16
Barry: 0.8
Chantal: 0.6
Erin: 0.2
Total: about 52

The “AGW-causes-more/stronger-hurricanes” crowd need to up the 2007 numbers so badly that if GABRIELLE had somehow geared up in Boston harbour it would still be counted as a TS.

The season is almost over the Siberia express is locked in, looks like a below average storm season to me.