Nasa scientist says this decade warmer than last
and that was warmer than the one before and that was warmer than the one before but Lewis says its not.
Phew not a scorcher then!
The two major US temperature databases have released their consolidated results for 2012, and as had been expected, global warming has failed to occur for approximately the fourteenth year running. One of the US agencies downgraded 2012 to tenth-hottest ever: it had been on track to rank as 9th hottest. The tenth-hottest …
There's this quote:
"The five-year mean global temperature has been flat for the last decade, which we interpret as a combination of natural variability and a slow down in the growth rate of net climate forcing."
Which comes in a paper from the well known climate change denier James Hansen, so which NASA scientist were you thinking of?
NIWA (our very green-slanting climate botherers) crowed that the 2000-2009 decade was hotter than the 1990-1999 decade. Read past he headlines and it was up by a whole hundredth of a degree.
Giving them the benefit of the doubt (ie. that they used an apples-for-apples comparison), one hundredth of a degree over ten years is a difference of 30 degree days. One cold front would have changed the result.
Statistical significance and science left the building a long time ago. There are only ideologists left.
"However one slices it, the world has not warmed up noticeably since 1998 or so"
"What matters is this decade is warmer than the last decade, and that decade was warmer than the decade before."
I know both sides of the debate love to cherry pick, selectively quote and misrepresent the other. For example 1998 is frequently chosen as a data point, even though it was an exceptional year. And data that contradicts the belief system is routinely ignored
Is it even possible to find a rational voice amidst the doom mongers and the "la-la-la fingers in the ears" bunch ?
Not sure The Register is the best place to ask that question though.
"Dumb article, check byline, yep, they still employ Lewis Page and haven't sacked him yet. Maybe he should try writing a well researched, logically consistent article, I'm sure the number of people commenting on how hell had frozen over would do the trick."
Indeed. Maybe you would now be so gracious as to provide both your author and article critique by way of a well researched, logically consistent riposte?
Is it even possible to find a rational voice amidst the doom mongers and the "la-la-la fingers in the ears" bunch ?
Possible, yes, but how would you pick out the rational voice with real, unbiased research from the mountain of quotes from studies crafted to meet one predetermined finding or the other?
It is true that deniers like to compare to 1998, which as you say was an exceptional year. But the warmists seem to have had no trouble cranking the alarm bells up to 11 when the stats for 1998 came in, with their claims that warming was accelerating exponentially. That turns out to be have been decidedly not the case.
The warmists have pointed to the USA's exceptional 2012 as "further proof" of global warming. If the deniers can't use exceptional years, why can the warmists?
I particularly enjoyed how warmists used the wet 2012 in the UK and the drought in the US simultaneously as proof. On the news last night I heard someone in the UK arguing how warm air holds more water and that was why it was so wet in the UK. Just last week someone in the US was arguing that the drought was exactly the type of "extreme weather event" that global warming causes.
This again is the big problem with global warming. EVERY weather event and trend, short of a multidecadal temperature decline, can be linked to it. If it can't be falsified, it is not worthy of being called a theory.
I think the difference is that the UK is an island and the US is a continent. Warm air coming over the UK has usuall travelled over the Atlantic first, so has had the chance to pick up more water and then drop it all over the country. In the US, warm air that's picked up water from the Pacific has already ditched it's moisture on the Sierra Nevada before reaching the nasty dry bits in the middle.
It takes 17-years of data to statistically prove the existence of Anthropogenic Global Warming (AGW), because natural variability has a larger effect than AGW in the short term (<10 years).
"Global land temperatures have increased by 1.5 degrees C over the past 250 years, and about 0.9 degrees in the past 50 years." - the Berkeley Earth team.
Therefore, in the last 10 years there should have been 0.09 degrees C increase in temperature due to Human activities, but a very small -0.09 degrees C variation in global climate due to natural variability would easily hide this long term warming trend.
No climate scientist would ever point to single or local event as evidence for or against AGW, it is only noticed when looking at the long term trend.
Santer, B.D., et al., 2011. Separating signal and noise in atmospheric temperature changes: The importance of timescale. Journal of Geophysical Research 116(D22), D22105.
Why "la-la-la fingers in the ears" bunch ?
I am probably in what you call that bunch and I am desperately seeking (that is looking with ears wide open) actual data that shows a warming tend. Has anyone ever shown any graphs of actual temperature? You think you have seen these graphs, but no you haven't. Look at the Y axis. Nobody shows graphs of actual temperatures.
Perhaps the warming of the two decades prior to 1998 was just natural variation and we all got carried away, incidentally has anyone taken a critical look at the record breaking temperature claims what they are based on and if the record temperature remains the same from year to year in the records?
"Perhaps the warming of the two decades prior to 1998 was just natural variation"
Perhaps. How might this "natural variation" have occurred? And what has meant that it has not reversed?
I'm all for alternative suggestions but just shrugging and going "well, nature did it" doesn't seem like enough.
I know the source is not liked by a lot of folk but this post suggests with evidence that NOAA's State of the Climate reports (STOC) that publish claims of "hottest day/year/month" on record are later adjusted down after being reported. It's easy to keep having records if you keep adjusting the previous "record" down.
We'd be months away from the first feasible working fusion power plant today had Bussard gotten the funding he needed instead of all the money being shunted into the war in Iraq. He knew how to do it, had the data to back it up, and couldn't get any funding because waging a war on the other side of the planet was more important.
"The globally-averaged temperature for 2012 marked the 10th warmest year since record keeping began in 1880. It also marked the 36th consecutive year with a global temperature above the 20th century average. The last below-average annual temperature was 1976. Including 2012, all 12 years to date in the 21st century (2001–2012) rank among the 14 warmest in the 133-year period of record. Only one year during the 20st century—1998—was warmer than 2012."
From the NOAA article you link to. The mood is in stark contrast to the article that links to it. As are the facts.
If you don't think a source is trustworthy, either explain why - or just ignore them. But don't take the bits that you agree with, ignore the rest and assume your readers are too stupid/lazy to click a link and read for themselves.
It's depressing and out of character with the rest of the site.
Reasoned debate on most subjects, but when it comes to anything with an environmental slant it descends to the levels of the Guardian or the Mail when they are pushing one of their pet agendas.
The annoying thing is that orthodoxies should be challenged. There is not "right way" that we should all follow without thinking. But please do it in an open and honest manner.
I trust this graph, because ...
The physicists who designed the satellite instrumentation don't have a political axe to grind, and the devices in all likelihood give the ONLY accurate global picture, as they actually sample the entire earth constantly.
Draw your own conclusions using the Mk. I eyeball.
@AC 17:38 - I note a few interesting things on that graph. I really wish I had more data to put it into perspective though. Taken on its own the graph holds little meaning. Yes, the world's hotter than it was 20 years ago, but we all know that already. The question that needs answered is not 'is it true' but 'why'.
Interesting you link to a version on Roy Spencer's site as he does have an axe to grind, he may be a physicist but he is also a creationist and very much against the AGW theory.
But go on use that Mk1 eyeball..notice how before 1998 most of the graph sits below the mean, and after 1998 above the mean? Particularly since the mean includes the above average period since 1998 (i.e. the mean is higher and thus the anomaly lower because of the inclusion of period of raised temperatures). Anyone still think nothing has happened since 1998?
You make the assumption that I have a position, and that position is that I am a "non-warmist" or anti-AGW or whatever name you want today.
You have no basis to conclude any such thing.
I linked to that graph because that is a convenient place to see the graphical representation of the data. Roy is one of the scientists that collate the data, not? You don't have to like the data, but I think that you attacking its reliability or accuracy is likely a fool's errand.
Assuming I have a specific agenda because I link to a published location of scientific data, says a lot about you, and absolutely nothing about me. For all you know I am Gavin Schmidt and my agenda is to show exactly what you believe the data shows. Any idiot can see a left-right upward trend, so what's your point? I will answer that, your point is that you are an idiot.
Feel free to provide a different link for future use so that morons like you won't be confused and impose their own flawed opinion on a neutral post.
I am completely confident in the GPS triangulation. The co-ordinates I receive are completely within the error bands that make them acceptable as a source for navigation.
The route planning software in my GPS navigation system installed in the car by a famous German manufacturer, on the other hand, relies on incomplete partial mathematical solutions to the routing problem, weighted according to the settings I provide.
In case you didn't understand, the GPS satellites are fine, the route finder math (for many good and provable reasons) less reliable.
"The last below-average annual temperature was 1976." Seeing as how -- though without benefit of a single graph or scientific quote but merely using memory alone -- I remember the long summer of 1976 in the UK as the absolutely sweltering hottest since the ditto long hot summer of 1959 (also remembered) it's no wonder so many of us are so confused.
The lengthy quote you chose does not in any way contradict what Lewis wrote - perhaps you need to read it again. Yes, the last 20 years have had most of the hottest years on record - Lewis's article repeats that quite explicitly. However, Lewis's article is about the fact that temperatures have stopped rising over the last 15-20 years. The fact that they DID rise BEFORE that is completely irrelevant to the point of the article. Note that a rise in temperatures to a record high 20 years ago followed by a 15-20 year plateau is totally consistent with your NOAA quote about the distribution of hot years in the record.
What Lewis didn't spell out explicitly, but perhaps should have done given the reading comprehension on display here, is that all the climate change / global warming theory and models predict that temperatures should have continued to rise, because CO2 emissions have continued to rise and the theories don't (yet) include any non-CO2 forcings that can account for the observed temperatures. Observation does not agree with the theory, and that is a problem for the theory, not for the observations, and not for Lewis.
Read it, *also* read a portion of the linked research. For instance, this bit
> 2012 marks the 36th consecutive year (since 1976) that the annual
> temperature was above the long-term average.
from http://www.ncdc.noaa.gov/sotc/global/2012/13, under Global Temperatures
So that's 36 consecutive years above the "long term average", which appears to be from 1880 to 2012. That is a rising trend. If Lewis has chosen to go back only 20, perhaps he's chosen that period to fit a pre-deternined view. Try running the numbers for 25, 30, and 40 years -- what do they look like?
Take a look at this year's temperatures across the continental US:
> In 2012, the contiguous United States (CONUS) average annual temperature
> of 55.3°F was 3.2°F above the 20th century average, and was the warmest
> year in the 1895-2012 period of record for the nation. The 2012 annual
> temperature was 1.0°F warmer than the previous record warm year of 1998.
Between @1760 and @1840 we had something called the industrial revolution. This involved the move to steam power, Machine manufacturing (rather than by hand) and from using wood to using coal for burning.
This resulted in heavy pollution. 1956 the UK introduced the first Clean Air Act to combat the problem of heavy smog that was covering much of the country. This smog obscured natural light, and affected ground temperatures, resulting in more coal being burned to heat up houses as it was rather cold, wet and miserable in the cities due to the smog.
Since 1956 there have been various acts to effect a cleaning up of air pollutants, the result of which has been a massive improvement of air quality. Cleaner, crisper, fresher air. Even the exhausts from cars doesn't come close to how bad things were back in 1954 (the year of smog that brought about the 1956 clean air act in the UK).
Now, that's just the UK. The US also introduced a clean air act to combat pollutants, and other countries have followed suite. This means that globally it was recognized there was a problem with air pollution and action was taken to fix this.
Changing the quality of the air will impact the climate. It will impact global temperatures. Why? Because we have removed particulates from the atmosphere that obstruct light, and hence heat, from reaching the planet surface from the sun. This is what French Scientists reported some years back. This is supposed to be a good thing as it means the planet is able to normalise: Reach the correct temperature for it's current cycle rather than an artificially low temperature as caused by the heavy pollution that has occurred since 1760.
What this suggests is that much of the global warming that caused panic amongst alarmist was not due to CO2, but due to the improving air quality. This does not deny climate change, nor does it deny the theories about CO2 being bad for the environment. However, air quality is not included in any of the models used to predict climate change / global warming, yet clearly it should: It's a variable, not a constant, and it has changed yet is not accounted for.
So I am not surprised that global warming has flattened out. It suggests that either we have normalised to the cleaner air, or that pollution levels have risen again and are starting to cool the planet once more. Either way, it needs to be incorporated into the climate models, and it needs to be monitored. Then, perhaps, we might have a better idea as to what is actually going on and so predict what is to come much more accurately.
@PatientOne The cleanup factor you've mentioned is not one I've come across before. Thanks for mentioning it, I'll have to add it the the reading topics around the climate change models. I'll be interested to see how the research accounts for high-altitude absorbtion (which is where some of the missing sunshine will have gone) versus a higher level of reflection of the solar input.
If you happen to remember any pointer to where you ran across the reference I'd appreciate a pointer.
I was born not far from Burnley bavk in 46 and use to go to football matches there in the late fifties. Travelling over the hills the complete valley was visible and this was heavy smog now it's clear of that kind of pollution. The Chinese need to do the same thing.
You're still attacking a straw man. Neither Lewis nor I claimed that there has been no rise in global temps since 1880, nor did he or I claim that there has been no net rise over the last 25, 30 or 40 years. The article is about the FACT that there has been no net rise over the last 20 years, and the implications for the current theories explaining the rise since 1880 which do not explain how or why this plateau could have occurred.
or just ignore them. But don't take the bits that you agree with, ignore the rest and assume your readers are too stupid/lazy to click a link and read for themselves.» AC, what are you trying to do - ruin Mr Page's business model ?...
You miss the point. It takes time for the earth to heat and cool. Therefore the fact that its still warm having spent 30 years heating up a bit is no surprise.
What is the surprise (if you are an HONEST warmist) is that this is in total contradiction to the models that predict that it should be, if anything warming at an accelerating pace.
In short the data makes mincemeat of the model.
The whole warmista thing is looking a bit like Lehman brothers..
I too. Only humans seem to have them. But I wonder why this global warming is such a "heated" subject.
I can understand some hot air when it comes to things like Windows or iOS or Linux or GNOME or KDE or Android, you name it. But the fact is that we, and not anybody else, have polluted the sea. Just look a the Baltic or anywhere actually. Is that nice, is it good for us and who would not like that pollution to stop.
In the same manner we are polluting the air, our atmosphere. Just have a look at this:
That shit was not the result of a warming sun or an act of god. Nor was it in 1952 in London.
Now suppose you asked somebody in Peking if he is happy with the quality of the air and if he thinks something should be done about it. I bet he will tell you that something should be done about it.
Then imagine you ask him if he believes in global warning or not, and should the regime take steps to try to prevent it or not.
Right now the whole global warming discussion is at a level compared to some city where all the shit is left on the street because it is cheaper, that way, and the Town Hall is arguing and trying find out if it causes more broken bones each year or not, and how to we know with only ten years of data.
Unfortunately, AGW is being used as an excuse, nay demand to pump out more toxins and pollutants, in exchange for less CO2.
The most obvious example is replacing easily recyclable tungsten lamps with mercury-filled and PCB-containing CFLs. That's worsened as there's no separate ballast models so you could have a long-lasting ballast and replace the mercury-filled tube a few times - you must replace both together.
Almost all "low-carbon" technologies currently result in higher emissions of really damaging pollutants - just not here, as we mostly outsource the manufacture and disposal.
AFAIK it's a heated debate because I seriously question the money being spent on pie in the sky power generation projects that are unworkable/unviable. Worse still, I have a major issue with western countries encouraging the worlds poorest people to use the most expensive means of power generation available. I won't miss a perfectly good opportunity to use the word insidious.
It is, judging by the icicles on the window. Oh, wait, that's weather and it is winter ...
But seriously, there is a non-zero probability of another ice age no matter what we humans do, and should it come, it will be very, very nasty and not at all good for our survival.
Flame: Because we may need them ...
The logic of this article makes about as much sense as measuring the temperature at night, and using the results to claim that global warming has been stalled for the last 12 hours.
Look at this graph:
Solar output has been declining for much of the past decade. That decline has counteracted increased forcing due to increased CO2, leading deniers to claim that "global warming is stalled" for the past decade. Unfortunately for all of us, global warming is almost certainly going to un-stall as solar output increases over the next decade --- since it's pretty clear that this solar output thing is cyclical. Expect a series of scorcher years.
It makes more sense to use graphs that actually cover the last decade if that's what you're going to talk about, rather than a graph from wikipedia that stops at 2006.
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"global warming is almost certainly going to un-stall as solar output increases over the next decade"
Solar cycle 24 is not far off maximum - if not already peaked. So it's on the wane either now or shortly. Of course, in about 11 years time (assuming it's not late again) it should be building up towards the peak of cycle 25 but even that is expected to be somewhat weak.
Overall however it is suspected that solar activity over the longer term is on a decline. The exact opposite of what you state.
Can we have a link (from a reliable scientific source) to support your statement please - or are you just (1) poorly informed or (2) talking bollocks?
Yes, we're nearing a maximum of sunspots. But that maximum is much lower than the maximum we had in the year 2000, really only moderate.
So... if sun spots have anything to do with T on earth (which they do), then it's quite reasonable to expect that we might not be getting yearly RECORD BREAKING temperatures this year, even as global warming continues. But if you could have today's CO2 with sunspots of year 2000, you'd see a different story. Just wait a few more years... as CO2 continues to build and we happen to get another solar peak, we will expect to see a lot of records broken.
Conclusion: if you want to be honest about measuring the direction of the T of our planet, you need to average over more than a couple of years. And if you ACTUALLY want to know the truth... why don't you look at all the available data, including ALL thermometer readings, as Mike Mann did? Oh yes, I know why.. because you don't like the conclusions that pop out so obviously. Nor do you like the fact that this procedure has been repeated many times, even by former climate deniers funded by Koch money, and the result has been the same each and every time.
I'm not too sure either how (or why) you are drawing your conclusions. You're just not making much sense.
Now, let's put CO2 to one side for now and stick solely to solar activity, as that was where my argument lay...
Basically you are saying that global warming will, to quote, "un-stall" when the Sun begins to approach the peak of Solar Cycle 25. Correct?
I'm sorry, but that just makes little or no sense whatsoever when you consider that, right now, we are almost at (or indeed just past) the peak of cycle 24 and using your very own logic, we should now - being at or near to solar maximum - be experiencing a measurable and clear additional rise in average warming due to solar activity. Not only that but there should, using your logic, also be a clear cyclical rise and fall in average temperature that coincides with, or lags behind, individual solar cycles.
I think I can maybe see why you are drawing your flawed conclusion(s), but flawed they are.
It's possible that we may indeed see warming "un-stall" in a decade or so. But, should that be the case, that will not be due to normal solar activity (especially if the next cycle is, as anticipated, weaker than the current cycle).
You continue (in your second post) to say, "...you don't like the conclusions that pop out so obviously. Nor do you like the fact that this procedure has been repeated many times, even by former climate deniers funded by Koch money, and the result has been the same each and every time."
Again, your logic is flawed.
You assume to think you know what I think and what I don't based on a single post. Not only is that logic a mistake, you do your own argument no favours with such utterly absurd extrapolation.
It is no longer about gathering facts, but it is about twisting the facts to fit your own belief. So we have one camp that BELIEVES we are causing global warming which will lead to doom and destruction, and the other camp that BELIEVES we are not causing global warming and trying to fix it will cause economic doom and destruction. Both sides are heavily funded by companies/interest groups who have a vested interest in seeing one side prevail.
Seems like we have the right ingredients to start a war:
* False information.
* A perceived threat.
* A real opponent, which if we kill em will take away the threat.
Ps. Would be kind of poetic justice if the dinosaurs reign got ended by sudden climate change and our reign gets ended by the fear of it leading to a war in which we wipe ourselves out. I wonder what Darwin would have said about that one.
"Perhaps the warming of the two decades prior to 1998 was just natural variation and we all got carried away."
Roughly two decades before 1998 I was taught at school that the Earth was entering a new ice age. This was based on the observation that temperatures had been falling continuously since at least the 1930ies.
Someone please tell the idiot who wrote this article what "climate" is.
People like this leave me with mixed feelings. On the one hand, you hope they don't have any children. With a parent like that, not existing seems like the best option. On the other hand, you hope they have children, hoping that it might make them into better people and since it clearly couldn't make them any worse. On the third hand, if such a person already has a child, I suppose you have to count it as evidence of genetic insanity. After all, they say insanity is hereditary--you get it from your children.
However, I still feel sorry for the children who are going to inherit the mess of a world created by such morons as this author.
Please, enlighten we poor deluded fools. What is climate ? That thing that is always getting warmer every time some set of graphs show a line rising left to right or a set of averages over a time span ? Seems whenever a heatwave hits it is proof of global warming, and when people die in cold spells it is just weather. Every dry spell is a drought caused by global warming, every flood is caused by global warming. Some of us get tired of being threatened. Perhaps ElReg editors advice to commentards a year or two back may assist you to be more persuasive. In meantime, if you cant improve the silence, stay silent.
What is climate? If you look at Jim Hansen's articles, climate is the AVERAGE weather you get. It's a bell curve dstribution. And he has shown that the bell curve we're getting this decade is shifted significantly warmer from the bell curve we had for the 1950-1980 period. Make of it what you will. (Look up "climate dice" to see this topic in greater detail)
Even if global warming has "stalled," it's still stalled at a level that is significantly warmer than when I was a child. And it doesn't take a genius to see that glaciers and ice sheets are melting at an alarming rate --- rates that in most cases are increasing, certainly nothing like a "stall" there.
And think about it... we've spent decades pumping CO2 into the atmosphere as fast as we can, and we've been able to measure increases in global temperature since 1980. And now the year 2012 is within the top 10 hottest years ever. We would most reasonably conclude that things are getting warmer, although there is some noise in the year-to-year signal. But instead, we use the fact that 2012 is not THE HOTTEST YEAR EVER to conclude that global warming has "stalled" and we have nothing to worry about, and we should keep burning as much coal as we can? Crazy... Only someone with a pre-determined agenda would make that conclusion.
First of all, climate is an average of what weather you HAD, not what weather you GET. There is a distinct difference. You can not claim the climate has changed until after the fact.
You seem not to understand the significance of the climate not continuing to grow warmer over the last 14 years. The popular theory says increasing atmospheric CO2 will, through a variety of somewhat arbitrary feedback mechanisms, result in a dramatic rise in global temperatures, and that is why the temps rose during the '80s and '90s. We have continued to increase the amount of CO2 in the atmosphere every year for the last 14 years, without a corresponding increase in global temperatures. They are warmer than last decade, yes, but it has not been getting warmer even though the CO2 content is rising. If rising CO2 is not causing rising temps now, how can you have much faith in a theory that claimed CO2 was responsible for rising temps in previous decades? Read that last sentence again and see if you can come up with a solid reason to have continued faith in the global warming theory.
The primary importance of the lack of warming temps is that it is suggesting, more strongly each year the temps are flat, that the theories are WRONG. There is something more going on that we do not understand, and it would be foolish to take drastic action with such a lack of understanding.
I'm not one to cry the sky is falling, nor am I one to say that we humans have zero effect on climate. I think its possible that if the temperature has truly leveled off it could be due to the pollution cutting etc done over the last 20-30 years. Although if thats the case, we'll probably see a warming spike coming down the pike from all the stuff China has been pumping into the sky.
Nice hypothesis. But actually... cutting pollution, perversely, INCREASE warming in the short term. Because all that SO2 we pump into the atmosphere actually reflects sunlight. All the pollution over China actually keeps China a little cooler than it would otherwise be.
But I agree, China is doing its best to add CO2 to the atmosphere as fast as it can. Although it's still way behind the USA, in per capita CO2 output.
If you really want to know if climate change is occurring just check how much your insurance premiums have increased over the last few years.
Insurance companies are like bookies, they look to the odds and if their payouts are increasing because of more extreme weather events then they will be increasing premiums to cover the additional costs.
So, if the average premium is increasing inline with inflation then no climate change, if however they are increasing faster than inflation then there is something happening and odds on it is linked to climate change! In Australia in some places they have gone up by double, triple, 10 times... This does appear to be indicative of something...
Surface temperature is only one factor in the heat capacity of the world. With the high levels of Arctic Ice melt, I'm not totally surprised that sea temperatures are stable. Now when all the ice goes... There's something nasty lurking in the temperature of deep sea too BTW
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'But I agree, China is doing its best to add CO2 to the atmosphere as fast as it can. Although it's still way behind the USA, in per capita CO2 output.'
and there be our real problem....'per capita' i.e too many Human beings on the planet.. we have a 1900s birth rate and a 21st century death rate. Unless there is a global plan to control mass over population its either a global war or environmental destruction. Either way I/most here wont be around thankfully by then but our kids and grand kids are completely screwed.
After a great amount of research, and reading reams of technical studies, I am prepared to declare both sides of the argument right...and wrong. The short version is this:
Earth has been warming through natural causes since the Little Ice Age ended in the mid-1800s. There are too many theories as to why earth goes through warming and cooling cycles to list. By the 1940s, Man was impacting the climate. Pollutants and aerosols being pumped into the air blocked enough solar radiation to result in a distinct cooling of the earth's climate by the 1970s. That's when some popular stories were written about an impending ice age. But we cleaned up our act, and greatly reduced the amount of particulates being dumped in the atmosphere. The result was the earth's temperature to rapidly catch up to where it would have been without Man's interference. As with most systems, and with the help of an El Nino in 1997, it slightly overshot, and is now in abatement until it's back on its original track.
So, does Man impact the climate? Yes, primarily through particulate air pollution, and urban warming. Does CO2 impact the climate? Negligibly. Are we on a disastrous global warming course? Maybe, but the warming will be virtually all natural. Spending trillions of dollars to reduce carbon dioxide would be a complete waste of money. I also question whether global warming, produced by any mechanism, is a 'disaster' in and of itself. I see a lot of benefit to Man having a warmer environment.
You can have your theories, but that's mine, and it fits all the known events. It is disprovable, of course. If we start warming again at a FASTER rate than, say from 1850-1940, then there is likely more to the story.
Always fun to see the more committed members of the pro-and anti-AGW sides beating seven colours out of each other.......
But where does any of this actually leave us (and we'll leave aside the implications of yesterdays announcement about black carbon being a more significant contributor to temperature forcing that had otherwise been held to be the case)?
Well, there's no inconsistency between there having been an extended flat period in temperatures, and the current decade being the warmest in the instrumented record. If you think, unless temperatures were actually falling, you'd expect the latest decade to be the warmest, if there's even a slight underlying upward trend.
And yes, there have been other flat periods in the record, and periods of fast rising temperatures (the 1930s), and even of falling temperatures ((the late '40s and 50s). All of that within a rising trend.
So, we know there's been a rising trend since the 1880s or so.
But, it's not a fast one. It's about 0.7 - 1.0 C/Century.
What was supposed to be important about the 1980s/1990s warming was that it showed that that trend had accelerated significantly, and showed signs of accelerating further.
It's now much more questionable that that's the case. What's more is that the basic forcing models for CO2 alone would give a rate of rise similar to that long term trend that we've seen for the last 130 years.. What was supposed to have changed was feedbacks from water vapour and methane emissions would act to make the rise even faster.
However, neither of those - either water vapour content in the atmosphere or methane levels - actually seem to be rising at any significant rate. So what was always some fairly flaky modelling around those looks as though it was wrong.
To sum it up - things are warming - but it's looking as though there's no real evidence that we've really departed from that 0.7 - 1.0C/century. The more lurid claims of 4-6C by 2100 start to look really exaggerated.
Which puts us in an interesting place - is a degree or so of warming by 2100 really a rate of warming that we can't live with? After all, it's about what we adapted to over the last century or so, without serious problems - and it may even be beneficial in terms of agriculture.
That's what needs to be being discussed.
Grand scheme of things: It doesn't matter. You're not going to give up your car, tv, computer, and cell phone so there are only two outcomes here. A: We are super warming the planet and will die or B: The temperature on the planet changes by itself and we might die. Either way there really isn't anything anybody can do about it unless we revert to rural farming communities and that isn't about to happen. So why argue?
Instead of arguing about whether a specific point on a graph is going up or down, why doesn't each side of the argument specify what data would cause their own theory to be DISPROVEN (a la Popper)? And then examine the data in the light of that assertion?
It seems to me that, if you believe in a strong and accelerating climate change due to increased CO2 concentrations, and if CO2 concentrations increase while the temperature doesn't, you have only two conclusions:
1 - the theory is completely wrong
2 - the theory partly right, but the effect is so weak that it is easily swamped by natural variation.
Of course, you could also argue that the data is incorrectly collected or processed in some way. But it would be a more interesting discussion than this continual argument about differing slopes on a variable graph...