Give me your opinions about global warming

[iNow]

Over the past 30 years that is true, as I have said repeatedly. However, before that, temperature rise and fall correlates much more closely with rise and fall of sunspot activity.

 

Super. So why is this at all important?

 

 

 

Peripheral to this conversation, quote tags aren't that hard to use, and make the readability of your posts skyrocket.

 

Their quoted text here. [ /quote]

 

Just take the spaces out. You'd be doing all of us who are not you a favor if you began doing this when quoting others.

[SkepticLance]

iNow said

 

"Super. So why is this at all important?"

 

It is not important. I am just annoyed that 1veedo in particular cannot seem to realise that the situation before 3 decades back was different.

 

One of the things that makes me very sceptical of the statements of IPCC is that they claim things that are not true. One of these claims is that anthropogenic greenhouse gases are the primary driver of global warming way before they become that important. This is siezed upon by certain contributors to this thread as if it were gospel, and repeated. There are still a lot of people who have not woken up to the fact that, in the IPCC, bureaucrats and politicians outnumber the scientists by a massive amount, and include their own agenda's into statements that should be pure science, but sadly are not.

 

Another commonly quoted statement from the IPCC is that 90% of warming over the past 50 years is driven by people. This is also not true, for the simple reason that the first 20 years of that period were actually global cooling. So why do they say 50 years? Simple. It sounds more alarming.

 

These are not the statements of scientists dedicated to the truth. They are the statements of politicians dedicated to their own agendas.

[iNow]

iNow said

 

"Super. So why is this at all important?"

 

It is not important. I am just annoyed that 1veedo in particular cannot seem to realise that the situation before 3 decades back was different.

 

One of the things that makes me very sceptical of the statements of IPCC is that they claim things that are not true. One of these claims is that anthropogenic greenhouse gases are the primary driver of global warming way before they become that important.

 

I'm clearly not as well versed on the data as you. Can you show me these points which are false? Perhaps an exact quote and/or link?

 

 

So much for the quote tags, eh?

[Fred56]

Um, just a comment:

 

1. There aren't so many climate scientists posting comments and/or analysis on SFN (except by proxy).

 

2. There aren't many posters to SFN who really know more about climate than climate scientists.

 

3. The scientists admit there are lots of things they still don't know or understand all that well about climate.

 

That said, there is no real problem with batting around opinion and speculation, as long as it is understood as such.

 

I don't think SFN is going to nail this issue (for the scientific community) any time soon. But the scientists seem to be saying it isn't going to go away, either. So there is plenty of room left for debate and discussion. Isn't that nice?

[bascule]

Another commonly quoted statement from the IPCC is that 90% of warming over the past 50 years is driven by people. This is also not true, for the simple reason that the first 20 years of that period were actually global cooling. So why do they say 50 years? Simple. It sounds more alarming.

 

Actually it's because about 50 years ago was when the effects of other forcing inputs started trending downward (causing the afforementioned net cooling effect) while CO₂'s forcing response was skyrocketing upward:

 

 

(yeah, only posted that image 5 billion times, but...)

[creato]

Basically i reckon that global warming is just a political tool used by goverments to achieve what they want.

( they'll probaly charge you for the gas cows emmit to help stop global warming)

 

 

 

good chart!!!

[creato]

hey look at this URL http://www.google.com.au/search?hl=en&sa=X&oi=spell&resnum=0&ct=result&cd=1&q=global+warming+charts&spell=1

[SkepticLance]

Bascule said :

 

"Actually it's because about 50 years ago was when the effects of other forcing inputs started trending downward (causing the afforementioned net cooling effect) while CO2's forcing response was skyrocketing upward":

 

But anthropogenic greenhouse gases have been increasing for at least 150 years before that time. And there is not a sudden increase from 50 years ago. In fact, the increase in the use of fossil fuels during WWII (1930 to 1945) was greater than the increase later, and yet the world cooled from 1941 to 1976 overall.

 

The statement was deliberately misleading, and for political, not scientific reasons.

 

Let me go into a little diversion.

 

Scientific conclusions come in a wide range of types - some credible, and some not at all credible. One of the factors which determines how valid a conclusion might be is what I call levels.

 

To illustrate, let me use the example of the satellites earlier mentioned that monitor solar irradiance.

 

Imagine that you are a technician monitoring the raw data from those satellites. You carry that data for a 24 hour period to a specialist scientist. That data could be called level 1. It is quite reliable. Not 100%, since the satellites are not perfect, and the sun is mildly variable.

 

The scientist takes the data and calculates solar irradiance in joules per square metre at Earth orbit. This is level 2. The results are still very reliable, but a little bit less so than level 1, since the scientist is human and fallible.

 

That data is then taken by another guy, who calculates how much energy strikes the Earth, at the top of the atmosphere. There is a small added error coming from the fact that the Earth is not spherical, and the energy arrival varies in total. Call that level 3.

 

Another guy takes the level 3 data and calculates how much energy hits the surface of the Earth. There are big error factors here, in that it depends on cloud and dust cover. Level 4 is a lot less reliable.

 

The next guy wants to calculate how much the soil will heat under that solar energy. He adds error factors based on soil type, which is not known to 100%. This is level 5.

 

The point is, that at every extra level, more errors creep in. The more levels, the less accurate. The kind of data that 1veedo and Bascule are presenting are way beyond level 5. Global climate computer models are more like level 25.

 

Those who believe that IPCC deductions amount to empirical data are just fooling themselves. There are so many assumptions, errors, and human fallibilities that we cannot even accurately estimate how much error might be built in.

 

I have seen a great many calculated results of solar forcings. They never relate to the known influence of sunspots. What value are they? I would say, little or none.

[1veedo]

SkepticLance you are trying to pretend that anthropogenic global warming has only been going on for the past 30 years when in reality humans have been steadily causing the Earth to get hotter for over 150 years now, and possibly even longer if you want to consider all the stuff about rice paddies in China and farming in other parts of the world. Just because the human impact on the climate has not always been the overwhelming factor does not change the fact that in the previous 150 years we have caused the Earth to get warmer by about a degree celsius. Where natural factors have caused the temperature to bounce up and down a little, human factors have steadily been pushing mean temperatures further and further up.

 

edit -- just have to specify that 1 degree C in 150 years comes from me reading a graph, the same one I posted earlier . The actual accepted figure, if there actually is one in the first place, is purely arbitrary.

[SkepticLance]

To 1veedo

 

If you look at climate history, you will see that there was a warm period from 900 AD to about 1350 AD. That was followed by a cold period lasting to somewhere between 1750AD to 1850 AD. Then it warmed again.

 

You are saying that the warming at the end of the Little Ice Age was a consequence of anthropogenic greenhouse gases. That is NOT the opinion of most climate scientists. Most regard it as simply a return from colder than normal conditions to normal conditions.

 

However, the warming of the last 30 years is not a normal return. It is faster warming than normal and correlates with AGGs.

[1veedo]

I'm calling red herring and straw man on your above post. You can't just talk about irrelevant topics and/or create straw men and magically think your post somehow pertains and/or refutes my previous post. That would be like me rambling on about nothing and finishing up with, "and that's why you're wrong." It's just not good style.

You are saying that the warming at the end of the Little Ice Age was a consequence of anthropogenic greenhouse gases.

No.

Most regard it as simply a return from colder than normal conditions to normal conditions.

But on the same topic the climate does not just go back to the way it was. Cool periods are not followed by warm periods and vice verse. I don't know why so many people assume this; I guess it's just natural for humans to think this way or something but I can guarantee that scientists don't regard it as simply a return from colder than normal conditions to normal conditions. The Earth should actually be getting cooler right now anyway -- scientists more or less regard global warming as a 180 degree turn away from "normal."

However, the warming of the last 30 years is not a normal return. It is faster warming than normal and correlates with AGGs.

You and your correlations. That's what's wrong with your whole "1941 to 1976" reasoning. Yes CO2 levels were high back then but so was particulate pollution. Particulates have the effect that they black the sun and cool down the planet, hense why between "1941 to 1976" the Earth cooled.

 

Of course I'm sure the recent increase in temperature is primarily caused by CO2 but this recent ~.6C degree increase is not the only effect we've had on the climate. Anthropogenic factors have been steadily causing the Earth to get hotter for over 150 years now. Just because the human impact on the climate hasn't been as overwhelming as the past 30 years doesn't mean we haven't been doing anything. In fact, again, if you look at the nice charts I posted above the Earth would be an entire degree cooler today if we were to remove the human impact on the climate from the picture. If we were following your logic on the other hand the Earth would only be .6 degrees cooler.

[bascule]

But anthropogenic greenhouse gases have been increasing for at least 150 years before that time.

 

What does that have to do with the forcing response?

 

And there is not a sudden increase from 50 years ago. In fact, the increase in the use of fossil fuels during WWII (1930 to 1945) was greater than the increase later, and yet the world cooled from 1941 to 1976 overall.

 

Are you familiar with the concept of a complex dynamical system? The climate system is nonlinear and filled with feedback loops. There is not a direct correlation between increases in CO₂ levels and CO₂'s radiative forcing, due to nonlinearities in both the carbon cycle and the climate system as a whole.

 

The statement was deliberately misleading, and for political, not scientific reasons.

 

Since you still don't get it, here's the graph modified to show the relevant time period:

 

 

Can you explain to me how this graph doesn't corroborate the IPCC's argument?

[creato]

Hey the graph is a bit outdated

[iNow]

Hey the graph is a bit outdated

 

It's not like it came from the 1800s. It's from 2001.

[SkepticLance]

1veedo said :

 

"The Earth should actually be getting cooler right now anyway -- scientists more or less regard global warming as a 180 degree turn away from "normal."

 

This may or may not be correct. I have seen references, by different scientists, to expectations that without humans the world will cool or will not cool. We just do not know.

 

"That's what's wrong with your whole "1941 to 1976" reasoning. Yes CO2 levels were high back then but so was particulate pollution. Particulates have the effect that they black the sun and cool down the planet, hense why between "1941 to 1976" the Earth cooled."

 

This is one of those terrible hind-sight predictions. The whole anthropogenic global warming thing took off about 1980. Of course, the question then arose - What about the cooling of 1941 to 1976? Somewhat embarassing since greenhouse gases were steadily rising while temperatures dropped. Someone came up with the idea that it must be sulphate aerosol pollution that caused the cooling.

 

That has never seemed very convincing for the simple reason that sulphate pollution did not suddenly appear in 1941 and suddenly disappear in 1976. It was certainly present in large amount before 1941, and there is actually a hell of a lot of it right now, from Eastern Europe and China air pollution, with the associated acid rain etc.

 

However, sunspot activity by comparison DOES suddenly increase and fall. It fell substantially for the first half of the period in question. The global temperatures then stabilised, and started rising again from 1976. The period of about 1955 to present saw sunspot activity remaining fairly steady apart from the 11 and 22 year cycles, thus not affecting temperature change to any significant level.

 

"Just because the human impact on the climate hasn't been as overwhelming as the past 30 years doesn't mean we haven't been doing anything."

 

Actually, if you re-read my posts, you will find I have not denied that. Any increase in greenhouse gases clearly will increase the insulating effect of the atmosphere and cause warming. What I have been saying, is that the effect of changing sunspot activity is greater, at least prior to 1976. If you re-check the graphs, you will see that rises in AGGs before the 20th Century were relatively trivial, and thus had a trivial effect.

[bascule]

What about the cooling of 1941 to 1976?

 

You mean 1960?

Somewhat embarassing since greenhouse gases were steadily rising while temperatures dropped.

 

Hint: There's more than one radiative forcing

 

Someone came up with the idea that it must be sulphate aerosol pollution that caused the cooling.

 

Yep, "someone" did, and: Decreased solar irradiance, increased volcanic activity, and increased UV blocking by ozone.

 

Again: There's more than one radiative forcing.

 

That has never seemed very convincing for the simple reason that sulphate pollution did not suddenly appear in 1941 and suddenly disappear in 1976.

 

Nobody's saying it did. It varies *gasp*

 

It was certainly present in large amount before 1941, and there is actually a hell of a lot of it right now, from Eastern Europe and China air pollution, with the associated acid rain etc.

 

Ever heard of volcanoes?

 

However, sunspot activity by comparison DOES suddenly increase and fall.

 

You are aware the other forcings fluctuate too, right? Do I need to paste the graph again? Here you go:

 

 

Look at them, all moving up and down like the complex dynamical system that they are.

 

It fell substantially for the first half of the period in question. The global temperatures then stabilised

 

Temperatures don't stabilize, they fluctuate, because they're resultant from a complex dynamical system. Do you understand the concept of non-linearities?

 

and started rising again from 1976.

 

Actually they started rising again in 1960. Still not sure where you're getting 1976 from. Your ass? I've asked you dozens of times and you've never responded.

 

Soooooo... no response to my post? I hope you don't mind me bringing this up again because you've only brought it up a few dozen times and I'm tired of hearing it:

 

Another commonly quoted statement from the IPCC is that 90% of warming over the past 50 years is driven by people. This is also not true

 

So, this means the blue line is on top. Have a look at this graph. Is the blue line on top?

 

 

Why yes, the blue line is on top! Can you drop that argument already? You're wrong.

 

Seriously SkepticLance: The graph I linked answers all of your questions, disputes, etc. I don't know why you keep bringing them up again and again and again. You seem to either think you know something the climate science community doesn't or that the climate science community is being dishonest.

 

Do you dispute the forcing inputs used in that graph or not? If you don't, then it answers all the tiresome questions you've raised again and again and again.

[Chris C]

Creato, try the graph from the AR4:

 

 

From about 1940 to 1970, starting with increased industrial production during WW2, output of sulfate aerosols and other particulates did in fact increase dramatically. After regulations caused a decrease, and CO2 rose higher, the positive forcing overwhelmed the negative forcings. Interesting to note that some parts of the southern hemisphere may have been warming during this time (Stanhill and gunn, 1975). We do know though that aerosols are doing a good job of masking a lot of warming today, as you can see. This can be significant becuase if we reduce this pollution we might actually get more warming, and if it were to increase you get cooling but other problems like smog, acid rain, etc. The effects aren't perfect opposites so you get different places reacting differently.

 

Chris

[SkepticLance]

To Bascule

 

We have been through all this before. You, like 1veedo, believe anything that comes from the IPCC must be as if written by God. Sorry, it is not so. IPCC is a bunch of a few scientists, and an enormous number of bureaucrats and politicians who put out whatever fits their own agenda. I have no doubt that most of the scientists are honest, but it is hard to get around the personal agendas of so many non scientists.

 

The various forcings that you like to quote are a case in point. They are the results of calculations, that work on the results of other calculations, that work on the results of yet more calculations. They are so far removed from reality that the error factor is huge. The fact that they show minimal impact from solar forcings, when direct historical data shows it is large is a case in point.

 

As long as you believe fervently in the divine nature of IPCC calculations, you and I will never agree.

 

You said :

 

"You mean 1960?"

 

Temperatures fell from 1941 to about 1960, correct. However, they stayed relatively stable (and when I use the word 'stable' it is intended to be a relative term) until 1976. Since this discussion is about warming, I used the 1976 date. 1976 is the date representing the beginning of the current warming trend.

 

You have seen this graph before.

 

http://www.mps.mpg.de/images/projekte/sun-climate/climate.gif

 

In one sense, it is also fallible because the sunspot activity has been converted to a reconstructed irradiance. However, it shows, from 1860 to 2000 in a way that reflects numerous other similar sets of data, the close correlation between sunspot activity and global temperature.

 

If you can see the way sunspot activity is related to temperature from this graph, and a number of others, you will understand how the IPCC calculations of solar forcings cannot be correct.

[bascule]

IPCC... God... enormous number of bureaucrats... politicians... agenda... personal agendas... non scientists.

 

A barrage of ad hominems. You're off to a great start.

 

The various forcings that you like to quote are a case in point. They are the results of calculations, that work on the results of other calculations, that work on the results of yet more calculations.

 

So's the standard model. The calculated forcing inputs represent the culmination of decades of research into the climate system.

 

They are so far removed from reality that the error factor is huge.

 

They're used as inputs into climate models, and successfully reconstruct the instrumental record.

 

Do you think the models were deliberately designed to make those forcing inputs work?

 

Why can't any of the naysayers develop contradictory forcing inputs and models which reconstruct the instrumental record, develop models where accepted forcing inputs don't work, or *gasp* develop forcing inputs that can reconstruct the instrumental record from existing models?

 

Temperatures fell from 1941 to about 1960, correct. However, they stayed relatively stable (and when I use the word 'stable' it is intended to be a relative term) until 1976. Since this discussion is about warming, I used the 1976 date. 1976 is the date representing the beginning of the current warming trend.

 

Let me borrow an argument from you:

 

This is not true, for the simple reason that the current warming trend started in 1960. So why do you say 1976? Simple. It better fits your agenda.

 

You have seen this graph before.

 

Yes, and we've been down this road before, and it got us nowhere.

 

If you can see the way sunspot activity is related to temperature from this graph, and a number of others, you will understand how the IPCC calculations of solar forcings cannot be correct.

 

If you can see why the earth's radiative balance is dependent upon the complex interplay of multiple, constantly changing forcings which operate within a complex dynamical system, you'll realize why that argument is bullshit.

[Fred56]

What I can't get my head around in all this is why some people believe that climate scientists must all be lying, or seriously deceived, or just after funding (so they can keep fooling the public presumably). Science is science. It's that simple. The really odd thing is that many of these “folks” also seem to have a lot of faith in science (as long as it isn't climate science). In other words we can trust all the scientists, but if one of them claims to know about the climate, they should be stood up against the nearest wall and shot.

[swansont]

The various forcings that you like to quote are a case in point. They are the results of calculations, that work on the results of other calculations, that work on the results of yet more calculations. They are so far removed from reality that the error factor is huge. The fact that they show minimal impact from solar forcings, when direct historical data shows it is large is a case in point.

 

"Math is hard" isn't much of a critique, IMO. It certainly doesn't make it wrong.

 

Um, just a comment:

 

1. There aren't so many climate scientists posting comments and/or analysis on SFN (except by proxy).

 

2. There aren't many posters to SFN who really know more about climate than climate scientists.

 

3. The scientists admit there are lots of things they still don't know or understand all that well about climate.

 

That said, there is no real problem with batting around opinion and speculation, as long as it is understood as such.

 

I don't think SFN is going to nail this issue (for the scientific community) any time soon. But the scientists seem to be saying it isn't going to go away, either. So there is plenty of room left for debate and discussion. Isn't that nice?

 

The problem with point #3 is that while there is always more to learn and scientists don't know everything, the converse is not that scientists know nothing. Unfortunately, a lot of the global warming criticism boils down to that. There is also the mixing of political arguments with scientific ones, which makes debate and discussion difficult, since they use different rules.

[SkepticLance]

Some people have a funny idea about what constitutes science. Science is not based on calculations as its mainstay. Calculations are a tool. Nothing more. They can be valuable, or misleading, depending on the situation. Modern science is based on empirical testing. The results of calculations have value in direct proportion to how well they are verified by empirical testing.

 

That is the reason why global climate models are suspect. They are castles in the sand, in that there is little clear empirical testing to support or refute them. The fact that over the past 30 years warming correlates with greenhouse gases appears to support them, but when the models are used to retroactively predict what happened before 1976, they start to fall apart.

 

Please take note also : misquoting me is not an argument.

 

Swansont said

 

"Math is hard" isn't much of a critique, IMO. It certainly doesn't make it wrong."

 

Re-read the post. That was not the argument. Your statement is just a red herring.

 

Fred said

 

"What I can't get my head around in all this is why some people believe that climate scientists must all be lying, or seriously deceived, or just after fund"

 

I suggest that you, too, re-read the posting. Again, that is not what was said.

 

Bascule said :

 

"Why can't any of the naysayers develop contradictory forcing inputs and models which reconstruct the instrumental record, develop models where accepted forcing inputs don't work, or *gasp* develop forcing inputs that can reconstruct the instrumental record from existing models?"

 

Do you think that making the same mistake a second time is a good strategy?

 

Bascule also said :

 

"This is not true, for the simple reason that the current warming trend started in 1960. So why do you say 1976? Simple. It better fits your agenda."

 

Please do not engage in deliberate deception. You are as aware as I am that any warming from 1960 to 1976 is trivial. The real warming happened after 1976.

 

Bascule also said :

 

"If you can see why the earth's radiative balance is dependent upon the complex interplay of multiple, constantly changing forcings which operate within a complex dynamical system, you'll realize why that argument is bullshit."

 

The complexity of the system is exactly why your arguments are wrong. We know that after 1976 that AGGs are a dominant force, and we know from the historical record, that in earlier periods, sunspot activity is dominant. There are doubtless many other inputs, some of which are currently unknown. A whole raft of both positive and negative feed-back mechanisms will be in play, some of which we are aware of, and some of which we are not. It is the arrogant assumption that we know it all and can predict it all that gets to me.

[swansont]

Some people have a funny idea about what constitutes science. Science is not based on calculations as its mainstay.

 

That, by itself, is a funny idea about science.

 

 

Calculations are a tool. Nothing more. They can be valuable, or misleading, depending on the situation. Modern science is based on empirical testing. The results of calculations have value in direct proportion to how well they are verified by empirical testing.

 

That is the reason why global climate models are suspect. They are castles in the sand, in that there is little clear empirical testing to support or refute them. The fact that over the past 30 years warming correlates with greenhouse gases appears to support them, but when the models are used to retroactively predict what happened before 1976, they start to fall apart.

 

The graph that bascule has repeatedly posted shows really good correlation with the model for the last 100 years. That the modeled temperature and GG curves do no move in lock-step over that time is not a failure of the model, it's because there is more than one parameter to it. Your requirement that there be correlation with but a single parameter is without basis.

 

Please take note also : misquoting me is not an argument.

 

Swansont said

 

"Math is hard" isn't much of a critique, IMO. It certainly doesn't make it wrong."

 

Re-read the post. That was not the argument. Your statement is just a red herring.

 

That's what it boils down to. The model is complex, therefore we can't trust it. And yet, when you discuss the details, it's clear that you don't understand the model. Attacking its complexity without specifics about the science is a political tactic. You're free to come up with a better model and data, but bascule already addressed this, and your response seemed to be that no model can ever work. Argument from ignorance.

[Fred56]

SkepticLance:

Please note I used the term "some people" and not "SkepticLance". My apologies if my comment was taken as a personal slight.

[SkepticLance]

Fred

I do not readily take offense. However, my highest respect to you for the apology, even if it was unnecessary. Only quality people offer apologies.

 

Swansont said :

 

"Your requirement that there be correlation with but a single parameter is without basis."

 

Re-read my posts. I did not require a single parameter. There are numerous parameters governing climate change. This makes the issue highly complex. However, there are sometimes dominant parameters, rather than single parameters. You would not argue with the statement that, over the past 3 decades, anthropogenic greenhouse gases have been the dominant parameter driving global temperature change. Would you?

 

So why is it so difficult for you to grasp the simple fact that, in times before those AGGs became so potent, that sunspot activity was then the dominant driver?

 

Here is another report discussing the issue

 

http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2004/07/18/wsun18.xml

 

"The team studied sunspot data going back several hundred years. They found that a dearth of sunspots signalled a cold period - which could last up to 50 years - but that over the past century their numbers had increased as the Earth's climate grew steadily warmer. The scientists also compared data from ice samples collected during an expedition to Greenland in 1991. The most recent samples contained the lowest recorded levels of beryllium 10 for more than 1,000 years. Beryllium 10 is a particle created by cosmic rays that decreases in the Earth's atmosphere as the magnetic energy from the Sun increases. Scientists can currently trace beryllium 10 levels back 1,150 years.

 

Dr Solanki does not know what is causing the Sun to burn brighter now or how long this cycle would last.

 

He says that the increased solar brightness over the past 20 years has not been enough to cause the observed climate changes but believes that the impact of more intense sunshine on the ozone layer and on cloud cover could be affecting the climate more than the sunlight itself."