Man Made Global Warming - yet another opinion

Cardew

OK you have convinced me that Global warming is not caused by banana production.

However I am sure you get my point!!

geordie_joe

Cardew wrote: »

OK you have convinced me that Global warming is not caused by banana production.

I think it's caused by shark attacks. If you look at a graph with one line showing the number of shark attacks, and another showing the temperature, the two lines are a much better match than any co2/temperature graph.

geordie_joe

Ben84 wrote: »

I think it's more like 0.04% by volume, your figure is ten times too high.

Typo, it should have been .035%.

Ben84 wrote: »

However, don't let the seemingly small quanitity of carbon dioxide mislead your understanding of the effect is has on the atmosphere.

Only some of the gases in the atmopshere are able to absorb and retain solar energy as heat in the atmosphere, while the rest have no effect.

Nitrogen (aprox. 78% of atmopshere), oxygen (aprox. 20%), and noble gases (about 1%), which in total are about 99% of the atmosphere on average have no ability to absorb and trap heat. The only reason earth is not extremely cold (minus more than 100c) is due to the ability of greenhouse gasses that make up some of the the remainder of the atmosphere to absorb and retain solar energy as heat. These gases are water vapour, carbon dioxide, methane and other less important ones. Carbon dioxide, as I hope you can now see while not a large fraction of the total atmosphere is a significant fraction of the greenhouse gases.

So what you are saying is all the heat in the atmosphere is contained in only 1% of it's mass (or should that be volume?). Either way, as CO2 is only .035 - .04% it is far less important than the gasses that make up the rest of the 1%

Another point, if only 1% of the atmosphere can absorb and retain heat, what happens to the heat/infra-red radiation that misses this 1%. By my calculations that should be about 99% of it?

As someone pointed out earlier, CO2 is distributed evenly around the earth. If this is true then all the other gasses should be distributed evenly too. If these gasses absorb heat, then get distributed evenly around the earth, presumably by the wind, why are some parts of the earth cooler than others? Surely they should carry the heat with them?

geordie_joe

Ben84 wrote: »

You expect others to go to great lengths to present their reasoning in deep detail, which would be fair enough if you were sharing anything on this level of detail and well supported by evidence, but when I asked you earlier if you had seen any evidence against global warming that wasn't from the mass media this was really your best reponse?

Yes but you are saying something is happening and there is scientific proof of it. I was just asking to see the proof. So far all you have produced has been as much use as saying "someone said it was"

I said that I can't see that it is happening, I may have only my experience of the temperature to go by, but that is more than you have produced.

cepheus

GEORDIE You seem to be missing my point, it is not suprising that shark attacks (on man) are correlated with global warming because both are caused by the presence of man.

It is not the heat contained in the gas, it is the special properties of certain gases that allow them to absorb re-emitted infra red (heat) radiation from the ground. Oxygen and nitrogen (99% of the atmosphere) are transparent to such radiation and will have no effect. Neither should we be surprised that the low concentrations of CO2 have such a profound effect, it is not the only greenhouse gas. Methane traps heat at around 20 times that of CO2. N20 and CFCs far more than this, these are only present in parts per billion yet contribute significantly to the warming effect.

The temperature of any part of the earth is mainly dicated by the amount of solar radiation absorbed by the ground, hence because the sun is lower in winter less radiation per unit area is absorbed. The additional greenhouse concentrations added by man only adds a deg Celsius to this, but somewhat more at the poles. Once the sea ice melts and stops reflecting the suns rays it will begin to absorb solar radiation big time and start to melt the thick land glaciers much faster as well. Together with the expansion of the water this will cause the sea to rise substantially.

thescouselander

Really, I think the whole argument on whether climate change is man made is fairly irrelevant. Lets assume for a minute that the science is correct and there has been an increase in the earths temperature due to man made CO2 being pumped into the atmosphere.

The elephant in the room is that the atmosphere is a chaotic and non linear system therefore a reversal in the production of CO2 doesn't necessarily equate to a reversal in the trend of increasing temperature (even if CO2 caused the temperature rise to begin with).

So there is a risk that the atmosphere will not respond to a reduction in CO2. There is also the risk that even if the atmosphere will respond to a reduction in CO2 the world may not achieve the reductions needed to get the desired effect. These two risks combined mean there is a significant risk that the current policy to reduce CO2 will fail to have any effect.

Of course, it might be that climate change is not happening at all. Either way, the policy to CO2 emissions reduction is flawed.

Furthermore there is a risk, however small, that the scientists are wrong and the temperature increase has been caused by some other phenomenon outside of our control.

In my opinion, it would be far better to direct our efforts on mitigating the effects of climate change rather than trying to change the weather by reducing CO2 emissions (a technique that might not work)

A_fiend_for_life

@thescouselander

non linear might be the key phrase it would seem a good idea not to hit one of those positive feedback mechanisms imho.

if global warming is happening and you focus on mitigation how do you mitigate the effect of rising sea levels and expanding deserts?

cepheus

thescouselander wrote: »

Really, I think the whole argument on whether climate change is man made is fairly irrelevant. Lets assume for a minute that the science is correct and there has been an increase in the earths temperature due to man made CO2 being pumped into the atmosphere.

The elephant in the room is that the atmosphere is a chaotic and non linear system therefore a reversal in the production of CO2 doesn't necessarily equate to a reversal in the trend of increasing temperature (even if CO2 caused the temperature rise to begin with).

So there is a risk that the atmosphere will not respond to a reduction in CO2. There is also the risk that even if the atmosphere will respond to a reduction in CO2 the world may not achieve the reductions needed to get the desired effect. These two risks combined mean there is a significant risk that the current policy to reduce CO2 will fail to have any effect.

Of course, it might be that climate change is not happening at all. Either way, the policy to CO2 emissions reduction is flawed.

Furthermore there is a risk, however small, that the scientists are wrong and the temperature increase has been caused by some other phenomenon outside of our control.

In my opinion, it would be far better to direct our efforts on mitigating the effects of climate change rather than trying to change the weather by reducing CO2 emissions (a technique that might not work)

Well this is a more reasonable point of view, although the part in red doesn't really follow on from the rest of the reasoning since CO2 reductions may work, and it is very unlikely indeed that GW isn't happening.

My view is that we really need as many bites of the cherry as possible.

• CO2 reductions may work and we need to conserve fossil fuel resources anyway so it makes sense to reduce CO2 as well as other greenhouse gases.
• Carbon sequestration, climate control and adaptation should be examined simultaneously although not as an excuse to ignore reducing GHGs
• We need a new political order to undermine this philosophy focussed on improving well being rather than materialistic gain (eg growth in GDP), this will also help to reduce GHG emissions

CFC

There is one thing in common to increases in Banana production and CO2 concentration, both have anthropogenic causes. Hence if something has happened in the last hundred that hasn't happened for thousands of years I would conclude that a human based cause is likely due to the rapid increase in human population and affluence.

Cepheus, you have no plausibility as your argument is deeply flawed and clearly driven by political beliefs, rather than your belief about what is going on being formed by argument.

I am certainly quite sceptical about global warming for a variety of reasons - but Ben makes good solid points which are worth thinking about.

cepheus

My belief is based on common sense and a basic knowledge of statistics. If something happens that hasn't happened for a long time and it coincides with something else that is novel we must become highly suspicious of a link and investigate it further. If theory then verifies this link (as it has in this case) we must take it seriously and act upon it.

Nearly every logical decision we make in life is based on this basic principle. That is why more than 99% of climate scientists agree with AGW.

Your sceptism is in contrast without any statistical or theoretical basis and highly motivated by right wing political rants encouraged by the fossil fuel industry and lobby groups. It is ridiculous to accuse me of being political in view of these facts!