Global Warming - Is it real, and if so is it caused by humans?

magma69

To be perfectly honest I do not have a strong opinion on this subject as I am fairly ignorant to the detailed studies on man made global warming. There is no doubt the world is heating up, there evidence is in abundance of evidence to back it up. Where I become stuck is the question of whether or not it is caused by humans. The only thing that sways my opinion is that the majority of experts in this field say we are causing global warming and when you not an expert you must place some degree of trust in their knowledge. It is a very weak opinion and one I am certainly willing to change however, as the scientists in the minority may be correct. Basically, due to my lack of expertees, I am undecided but if I had to get off the fence I would be in the "global warming created by humans" category.

If anybody knows of any good books on the topic which they have read, I would be grateful were to let us know.

Just a side note, I think the theories that the global warming theory was introduced so a carbon tax could be implemented is ridiculous. Carbon tax is going to cost companies money and the losses created in reducing their carbon is far greater than the gains generated from a carbon tax. It makes no sense.

bonkey

Duiske wrote: »

Anyone with an interest in climate change has heard about how, in the early 70's, scientists were sounding the alarm bells about Global Cooling.

And anyone who has gone beyond having an interest, and actually looked into the facts would have found out how, in the early 70s, scientists were doing no such thing.

There was uncertainty in the 70s as to whether or not the cooling effects from aerosols in the atmosphere would have a greater effect then the warming effect of increased greenhaouse gasses.

While there were some popular-media articles about how we were on the brink of a new ice-age, the consensus of the scientific community was that more research was needed to be able to say anything, one way or the other, with any confidence.

Although its hardly a canonical source, wikipedia gives a pretty-good account (complete with references) of how there was never a serious scientific community belief in global cooling. Some individualscientists supported the idea, sure, but that's not quite the same thing.

Around 1977 the PDO changed to its positive phase, and suddenly we had scientists talking about Global Warming.

Thats also not entirely accurate.

Again, wikipedia acts as a good link to the actual work done analysing what was studied when.

Duiske

Originally Posted by Duiske
Anyone with an interest in climate change has heard about how, in the early 70's, some scientists were sounding the alarm bells about Global Cooling.

bonkey wrote: »

And anyone who has gone beyond having an interest, and actually looked into the facts would have found out how, in the early 70s, scientists were doing no such thing.

Some individualscientists supported the idea, sure, but that's not quite the same thing.

Fair point, so i've edited my post to reflect that.

Bonkey wrote:

While there were some popular-media articles about how we were on the brink of a new ice-age, the consensus of the scientific community was that more research was needed to be able to say anything, one way or the other, with any confidence.

Scientists back then were doing exactly what they are doing now. Releasing exaggerated sound bites to the media to further their particular ideas.
I posted this last night in another thread on Boards, but it has some relevence to this.
This is from Stephen Schneider, a lead author of a working group within the IPCC.

On the one hand, as scientists we are ethically bound to the scientific method, in effect promising to tell the truth, the whole truth, and nothing but — which means that we must include all the doubts, the caveats, the ifs, ands, and buts. On the other hand, we are not just scientists but human beings as well. And like most people we'd like to see the world a better place, which in this context translates into our working to reduce the risk of potentially disastrous climatic change. To do that we need to get some broadbased support, to capture the public's imagination. That, of course, entails getting loads of media coverage. So we have to offer up scary scenarios, make simplified, dramatic statements, and make little mention of any doubts we might have. This 'double ethical bind' we frequently find ourselves in cannot be solved by any formula. Each of us has to decide what the right balance is between being effective and being honest. I hope that means being both.

By the way, Schneider is currently involved in the production of the Fourth Assessment Report from the IPCC.

At the end of the day, this whole doomsday AGW theory will fall apart over the next few years.

THE United Nations climate science panel faces new controversy for wrongly linking global warming to an increase in the number and severity of natural disasters such as hurricanes and floods.

It based the claims on an unpublished report that had not been subjected to routine scientific scrutiny — and ignored warnings from scientific advisers that the evidence supporting the link too weak. The report's own authors later withdrew the claim because they felt the evidence was not strong enough.

http://www.timesonline.co.uk/tol/news/environment/article7000063.ece

Unfortunately, they did not relay that fact to these kids, who still think they are going to die because of "Global Warming".
Didn't Al Gore tell us there was a scientific consensus on this ? And he will not debate the issue because "the debate is over" ?

bonkey

Duiske wrote: »

Scientists back then were doing exactly what they are doing now. Releasing exaggerated sound bites to the media to further their particular ideas.

If by "scientists" you mean "some scientists", then this is completely correct.

There has always been, and probably will always be, scientists who are perfectly happy to play the media either for their 15 minutes of fame, or to try and whip up public support for their concept.

Didn't Al Gore tell us there was a scientific consensus on this ? And he will not debate the issue because "the debate is over" ?

There is scientific consensus on it....which is also the major difference with the current stance regarding AGW and the idea of Global Cooling in the 70s.

If there could have been said to have been a consensus on anything in the 70s, it was a consensus that more research was needed to be able to say anything meaningful. There were, of course, those who disagreed...those who were certain that global warming was on the way, and those who were certain that global cooling was on the way.

Hidden in that statement is an important point. Consensus does not mean unanimity. its easy to point to this or that scientist, or this group or that group, and say "look...they disagree...how can there be consensus". All this shows, to be honest, its termed consensus and not unanimity for a reason....that reason being that not everyone agrees. Just most people (in the relevant fields).

As for Al Gore...personally, I couldn't give a fig what he says. He's not a scientist working in the relevant field(s). His opinion carries no more weight then any of those other people who offer opinions who are not scientists working in the relevant field(s).

When we look at the people doing the relevant science, there is consensus. There is not unanimity. There is not certainty. There is consensus with a high confidence level.

As a side point...there's the whole "GlacierGate" affair going on right now...about how the IPCC included a statement who's source ultimately turned out to be pretty shoddy. On one hand, this seems pretty damning. On the other hand, its worth noting that the error was found by scientists who support the theory of AGW, reviewing claims made by their own side, and then acting on them when they found them to be wrong.

And yet, we don't hear that side of things. We hear about how we're being lied to...how the scientists are out to grab grant money...how its all a lie, and how we can't trust any of them. Except, of course, when they say something we like, right?

Kernel

magma69 wrote: »

Just a side note, I think the theories that the global warming theory was introduced so a carbon tax could be implemented is ridiculous. Carbon tax is going to cost companies money and the losses created in reducing their carbon is far greater than the gains generated from a carbon tax. It makes no sense.

Carbon tax is goingtoo cost companies money, true. What companies do when they encounter increased expenses? Offset them by increasing pricing to the consumer. Don't forget that the consumer is also going to be paying carbon taxes on everything. The carbon tax is a global tax, proposed as going into globalist bodies. Read up on the NWO. Check out the Jesse Ventura Conspiracy Theory youtube video I posted a link to earlier in the thread. It's a good place to start as a layman in this complex field of thinking.

Yitzhak Rabin

NaDamantaSam wrote: »

There is a rough trend visible in the PDO graphs, of a negative period from around 1940-1973, a positive period from 1973 to about 2007 and we are now at the beginning of a negative period.

Its a very rough trend. If you look at the intermittent points, you can see, that it is a very short term cycle, and not a 50 year one.

This ties in well with the global temperature record during the time, and adding in the ever high solar activity during the 20th century, you get a general upward trend, perhaps slightly enhanced by CO2.

Its a very rough trend. If you look at the intermittent points, you can see, that it is a very short term cycle, and not a 50 year one. But thats not the case, solar activity has been showed a slight cooling over the past 35 years. The ENSO cycle does affect temperature, like you mentioned, the high El nino of '98, but that changes so frequently. How can it account for the unmistakable upward trend? particularily when you look at the cooling trend of the sun.

Here's a paper that might interest you http://www.cdejager.com/wp-content/uploads/2008/11/solaractivandclimate-nethjgeosci.pdf

I'm sorry, I've tried to read this a few times, but its very much going over my head. If you understand it can you dumb it down a bit?

NaDamantaSam

yekahs wrote: »

Its a very rough trend. If you look at the intermittent points, you can see, that it is a very short term cycle, and not a 50 year one.



Its a very rough trend. If you look at the intermittent points, you can see, that it is a very short term cycle, and not a 50 year one. But thats not the case, solar activity has been showed a slight cooling over the past 35 years. The ENSO cycle does affect temperature, like you mentioned, the high El nino of '98, but that changes so frequently. How can it account for the unmistakable upward trend? particularily when you look at the cooling trend of the sun.






I'm sorry, I've tried to read this a few times, but its very much going over my head. If you understand it can you dumb it down a bit?

Just moved into a new apartment today so don't have very much time I'm afraid.
Just one thing as regards TSI, sunspots and whatnot. It kinda work like a heating element, if you have water at a temperature of say 10C, and a heating element at say 150C, the water will inevitably heat up. By the time the water has gotten up to 30C, even if you reduce the temperature of the element to 100C, the water will still continue to warm up. Get me? Kinda works like that with the sun at the moment. Even if the TSI has dropped a little over the past 40 odd years, there is still enough to continue to heat the planet up. Obviously it's also just one factor in amongst an emmensely intricate system, but it is IMO the most important.
A more comprehensive reply later anywho!