The the issue has become politicized so that those on either side do not trust the other, especially when $$ and regulations become involved. The issue itself is poorly defined and presented. Most people would accept that climate change is happening, but the issue is really the extent of human activity impact. Bad or misleading information has been presented on both sides. Unfortunately public trust of science and the objectivity of science become a casualty in this process.

A related question: Even if we could agree that human activity has impacted climate change, do you think we as a global society could actually do anything to change that in a significant way? We seem to be riding on a runaway train.

It is evident that human activity impacted on the climate. In my country when I was child there were 4 seasons and one was able to predict the end of the winter and the beginning of the spring. Now we can say to have 2 seasons, one warm and one cold and it is difficult to predict the end of one and the beginning of the other. Besides the change is very strong with temperature change up to 10-20 degrees in few days. One week you are in the end of winter and in some days later you are full in summer. So there is an evidence of the change of the season and climate. Another thing is to set the cause of this change. I do not believe that all is due to the carbon dioxide; there are compounds with stronger greenhouse effect as methane and water that are sent in the atmosphere by human activities (farms, zootechnics, industry etc...).

The only thing one can say, and this is my opinion, is that the industrial activities, air travels, intensive agriculture, zootechnic effects had impacted very strong with the climate and the effect cannot be anticipated or rationalized, and that the planet equilibrium is searching another equilibrium point in this moment. What I am not sure is that the human race will be part of this equilibrium in the close future

There is of course human impact, but if you look in a global geological view, it is not that dramatic, as in geology we notice several cyclic "global and local warmings", and always there is disparition of species and apparition of others... Of course our life is better with less pollution and more preservation of the Biodiversity, but as stated R. Snyder the issue is becoming politicized ...

I agree with the cyclic effects but if you noticed the storms, tsunamis, earthquakes have become stronger and stronger; maybe someone politicizes but the effects are real and under everybody eyes

I remember some years ago a Pentagone document related to the global warming, then obscured by the same who commissioned the study. Below you can find an old (2004) text who notice the fact.

http://www.guardian.co.uk/environment/2004/feb/22/usnews.theobserver

By the earth sciences point of wiev there are a lot of evidence that the nature drive the planet forward an ice age, tsunami and other climatic evidence of the Mexico goulf current "malfuction", the north Atlantic Ocean its more cold than the past few years and the tropics is more damaged by climatic cataclysm.

That climate change is something natural. It is not more than a statistical concept. That the frequency of certain states of weather has changed significantly in a region is difficult to relate to human activity unambiguously (using CO2 as a proxy it is too coarse simplification). But relate to earthquakes and tsunamis, as it appears frequently in the press... the scientific basis of this escapes me.

From one hand we do have a continuously rising global temperature, with all that this implies, and from the other hand we do have climate and weather patterns to change periodically!!! Both are true and without any doubt!

We may be living in the "highest" of an interglacial period.

Since, human started "conquer" Earth only bad things can do to the enviroment. If we do want to be realists any change we cause to an initially "virgin" place cannot be good and is an envromentally bad practice. Some say, that the feedback mechanisms of the earth are very strong and can manage the human pollution. I think that the solution, and not the answer (because the answer requires a lot more years of data) is somewhere in the middle and comes from humans. If all of us, start to walk more or bicycle more and not use our vehicles, if we are willing to consume less (food, material goods etc) then we do can turn the scale towards the side of Earth and have a better place to live. Maybe we should first find the equilibrium for us and then let the earth find it for herself. Let's hope that will not be late (then those who believe in climate change due to human activity, unfortunately will be right)!

Coronal ejections and global warming

No doubt the world is hotter this year because the sun is going through turbulent times where magnetic variations in the surface cause occurs a phenomenon called coronal ejection more frequently and with greater intensity than usual. It's called Cycle Eleven Years of the Sun or Schwabe cycle, named after the German astronomer Samuel Heinrich Schwabe (1789 - 1875), the first to observe this phenomenon cyclical star.

This phenomenon interferes with satellite communications, increases the number (and beauty) of the aurora borealis and australis and promotes a slight overheating the earth's surface. The prediction is that this cycle, the 24th observed in history, has its peak in 2013 or 2014, and we can therefore expect that there are important variations in the global climate in the next two years.

Plateful to leave the talking aquecimentistas the usual nonsense ever; anthropogenic global warming, greenhouse cataclysmic losses agrarian and livestock, forest fires in the northern hemisphere summers churrascantes etc etc etc. ..........

Before you are again so pedantic go to the IPCC site on internet first man

ResearchGate is a scientific place not a blog with opinions

Craig Smeaton redirects the question well, "questions should be is climate change due to human activity, because no one can argue that global weather patterns are changing but how much of this is due to human activity." And I thought this sort of question is best answered by the isotope ratios of "heavy" carbon being more predominant in the recent record over the paleontological proxy recors, tree rings or ice core readings? By that I refer to the case where heavier carbon ions are the product of combustion, as opposed to plant or bacterial photosynthesis. Since the last century both "heavy" nitrogen and "heavy" carbon isotopes are more prevalent and that points to combustion as the source for these constituents of organic compounds. There are other reasons but the chemistry points to human acceleration of the post glacial warming from which human civilization has benefitted.

Joseph

Is this a double typo "heavier ions" are the product of combustion?

Are you referring to 14C? This absent in fossil fuels

Hello Harry,

Thanks for the question. Actually there are a few typing errors: "over the paleontological proxy recors, tree rings or ice core readings? By that I refer to the case where heavier carbon ions are the product of combustion" should read "in the recent as opposed to the paleontological proxy records, tree rings, or ice core readings? By that I refer to the case where heavy carbon ions predominate as they are more likely product of high temperature combustion. By heavy I should have specified C12 as readily available and C13 as the ion in question. One source I have for this conclusion is from:

Prosenjit Ghosh, Willi A. Brand, "Stable isotope ratio mass spectrometry in global climate research," International Journal of Mass Spectrometry, 228 (2003)pp. 1-33.

Therein these researchers make the point that (if you will permit my extensive quotes)

"While it has been possible for the past 50 years to measure the CO2 mixing ratio and the isotopic composition of air samples directly, this information must be recovered by more indirect means for the more distant past. Much of our quantitative knowledge of climate fluctuation in the past has been derived from records preserved in the ice sheets, and deep sea sediments."

(page, 16.)

"It represents one of the earliest results from ice cores exhibiting a general increase in CO2 concentrations with time since 1750 together with a decrease in carbon 13 isotope values. Using these data it was possible to directly compare measurements of CO2 concentrations in air obtained from Mauna Loa since 1958 by Keeling et al. with longer term ice core archive record from Antarctica. The average carbon 13 isotope value of samples before 1800 A.D. is –6.41% in the ice core." (Ibid., or also p. 16.)

I take from this and other evidence that contemporary isotope ratios of C12 : C13 deviate from what one would expect to find if the increased carbon dioxide we are measuring were of natural origins.

So the simple answer is no not C14, but the carbon 12 and carbon 13 ratios. I should have been that precise, and I appreciate your inquiry.

A good place to start:

http://www.realclimate.org/

Absolutely, do see this specific posting:

http://www.realclimate.org/index.php/archives/2004/12/how-do-we-know-that-recent-cosub2sub-increases-are-due-to-human-activities-updated/

Thanks for the reminder and a good suggestion.

I think that is not a global warming but is a global climate change. This change normally will occur in a big time but with the activity of men this occur more early.

Daniela

Global warming is part of Climate Change

Daniela

OK then

IPCC provides the data on the increase in temperature per region; so please show me where the temeprature has decreased in the last 50 years

For me, I would say questions like this are a a very representative microcosm of what is wrong with general perception of science, and how/what a scientific debate is - opinions are not in any way valid as an argument (contrary to the suggestion of the questioner). To echo words of Feynman, the world does not care what you think it simply is the way it is.

Yes, you are right. But the increase is big in some regions then other? Is a doubt that i have...

Daniela

The temperature increases most in the Arctic region and that is not good because the polar ice will melt more rapidly

Benjamin

Actually I wrote a similar comment a few days ago, an entry that is not visible anymore, accusing the questioneer to be pedantic and a charlatan

Ah apologies, I had not seen the full length of the comments section. Still, it is certainly good to know the sentiment is echoed.

Princess

Better, though is to go to the IPCC report of Working Group 1

The draft 5th report is here:

http://www.stopgreensuicide.com/

How many percent of the world´s surface has to warm before its called "global"? >50% >75% >95%? ...and what is the "time window" required? 30 yrs, 50 yrs of continous warming trend? In short: how is "global" warming defined? The question cannot be answered until this is clarified. (It is also interesting to note that the Medieval Warm Period is usually not regarded as "global" referring to the lacking coverage but also due to the out-of-phase warming patterns. This dismissal must be based on some sort of definition but I have not seen it worded anyhwere?)

Jan

The authority should be IPCC. Did you scan thru the report? This I directly found via google

"Definitions of climate change

Climate change in IPCC usage refers to a change in the state of the climate that can be identified (e.g. using statistical tests) by changes in the mean and/or the variability of its properties, and that persists for an extended period, typically decades or longer."

http://www.ipcc.ch/publications_and_data/ar4/syr/en/mains1.html

Harry, the term "global" is NOT defined in any of the IPCC reports. Not seen in the new draft either. It is probably assumed that the forcings are acting globally but surely it is the real climate response that counts (i.e. "warming") ? So, still, what is meant by "global"? A major blunder in the climate research community, I think.

http://www.grida.no/climate/ipcc_tar/wg1/pdf/TAR-APPENDICES.pdf

Jan

I 'll have look too, because that would indeed be a very dreadful omission. On the other hand they provide the regional changes, which are the scientific approach.

Climate change is a fact that has been supported by many indicators around the world for decades . The impact of man on climate change is well recorded since the industrial revolution by the increase in GHG concentration . Having said that the picture is still complicated even for scientists and they are still struggling with factors such as the role of suspended matter SS and volcanoes on cooling , the hot spots on the sun , the effect of El Nino and El Nano ...etc.

Saad! You say "the impact of man on climate change is well recorded since the industrial revolution by the increase in GHG concentration". I think nobody has disputed that GHG has increased. The questions is the impact on the climate. Today it is merely a guess in models, and not a particularly good one, I should add. The uncertainties in, climate sensitivity, the impact of aerosols, the elusive oscillations of the oceans etc etc make it difficult to untangle anthropogenic impact from natural variations. The last 16 years of unexpected temperature hiatus (while the GHG increased!) shows that we don´t have the grips on the climate system just yet. So global warming is a fact - not fiction. The size of it can be discussed. The IPCC wants us to believe that the case is closed (at least in the policy part) but as long as we don´t understand the natural variations, we simply cannot claim that we know the size of the anthropogenic impact on a global scale with any certainty. The high certainties, often claimed in various fora, are done so of political reasons, not from scientific ones according to my humble opinion. I share my views with Judith Curry on this topic.

Jan

NO it is not on the basis of models but on the basis of attribution that "global warming" is assessed.

Since you are familiar with IPCC reports you probably know where to find it.

Jan

Thanks for your comment . You agreed with me that GHG are on the increase since the industrial revolution . So this increase is anthropogenic . It is a scientific fact that GHG absorbs light in the infra red region and so it absorbs reflected heat from the earth . There bound to be an effect for GHG in increasing the temperature . But like I said there is still some uncertainties about the role of aerosols which the IPCC is only now starting to look into it and it requires a lot of research . The same goes for other factors such as hot spots on the sun which are not even fully understood yet . But this should not make us complacent . As the old wisdom say "better safe than sorry !"

Saad

IPCC has been aware of aerosols since 1994. As you mention they are complicated but there influence is much better restrained and in the AR5 their role has been decreased as compared to AR4; hence the climate sensitivity also will be lowered

Harry

Thanks for the comment . As I know the IPCC is aware of aerosols but there is no methodology yet to asses its effect quantitatively .

Harry. You can´t have one without the other. From IPCC: "Model and forcing uncertainties are important considerations in attribution research. Ideally, the assessment of model uncertainty should include uncertainties in model parameters (e.g., as explored by multi-model ensembles), and in the representation of physical processes in models (structural uncertainty). Such a complete assessment is not yet available, " From: http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch9s9-1-2.html

I am not referring to the popularized summary text but the real pdf-text of the same chapter

http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-chapter9.pdf

Saad

The uncertainty in the aerosol effects have been lowered considerably since the first estimates. Also its mean value has been lowered and thus its uncertainty also. As you know the effects are very difficult to quantify because of the highly variable character of the (manmade) aerosols. THus their contribution are modelled in stead of coming from observations

Harry! The quoted text also appear in the link you refer to. Models are very central for understanding the attribution. Sometimes it is the ONLY way to, at least, get a hint on what´s going on between the forcings (inlcuding the natural). You need that information to pin-point attribution. I, myself have done some modelling on aerosols, perhaps the most elusive forcing. The problem arises when the models are regarded as the golden standard and unfallable. Which they´re not.. Many of the policy conclusions from climate research is drawn from outcomes from models (i.e. the attribution: anthropogenic CO2 is the major climate driver and culprit). That would be allright if it wouldn´t affect our daily lives, but it does, through taxes etc and moral damnation (usually outside the research community) if you don´t swallow the oversimplistic conclusions uncritically.

Jan

I do not fully agree with you. In assessment of the anomalies a stratification and aggregation of data is needed. A "model" is used for this but not the complex modeling of projective predictions in which the complex GCMs are used with their full calculating power.

You mention aerosols but did not find it at your site. I notice a 1987 conference proceeding of the (Stresa?) symposium I attended and contributed to

I think, based on the results of some researches in Iran and other countries, the "Global Warming" is a proven fact at least for some parts of our planet, but for some other parts, not a proven fact yet . . .

Can you provide the references for that ?

Iran is only a very small part of the world and the discussion is on global warming

Constantin

Just to ask: the draft AR5 is already on the web; you knew that?

The second order draft was leaked several months ago by Alec Rawls, but i think there has since been another leak from a more recent version as well.

Constantin

I also only know of the recent SMP at Whatsup

An interesting question. I guess those who have been measuring the climatic variables on decadal scale can't say that it is not real. I have a temperature data set of 52 years that intrestingly shows the decadal variation. These are usually not only incremental but when an average is taken it is on a steady rise. However the problem is when global models generalize these observations to suit their preassumptions. I will like to cite an example of Ocean Acidification that is linked to climate change (increased green house gasses). In case of middle east in the Gulf corals are recorded, and growth is observed, though theoriticallly it should not have existed at a temperature of 35 - 37 oC and a pH of 8 - 8.1. I have been measureing the SST, pH, alkalinity, salinity in the region for past 8 years and I see how efficiently the natural system performs the balancing act. Until recently the pH drop was observed in the Gulf and salinity was on increase due to excessive desalination. Since June 2013 for the first time we started seeing slight rise in pH and decrease in salinity, possibly the increased salinity increased the buffering capacity and is neutralizing the pH.

regarding the myth of global warming and anthropogenic contribution. There is no point in geological history of past 800 Ma that CO2 concentration has increased 300 ppm mark. Now it is at 400 ppm so this suggest that there is an anthropogenic finger print over the natural cycle of GHG variation.

Saifuddin, annually averaged global temperatures show variations largely corresponding to the state of the oceans, and when you average over 10 years you will see fluctuations as a result. But identifying robust and significant periods/cycles in modern observational datasets of ~10 years is very unusual - if you have this you should publish!

Ken

Weather extremes also have their "average", so one single extreme can be a fluke/outlier. Statistics for extremes need a longer average possibly something like a century, so what can be learnt from a single extreme? Summer 1947 in the Netherlands is/was extreme, related to the unusual synopsis.

Ken

Started reading your attachment; however, I have the same problem as with 2 manuscripts I am currently reviewing on aerosol characteristics in some far-away "country". The problem is that one has to be a little acquainted with the regional situation also with respect to the meteo to appreciate the results and inference presented. And actually that does not work out unless the authors present their data in a wider context and in a more relative way for instance relative to data in a similar region or in this case similar climate class. Asssumingly the SW is a very inhomogenous region, varying from extreme desert to a mild Californian coastal region.

Ken

I fully agree that extremes are present; however the "IPCC" worry is that these will occur more frequently and even that the extremes will be more extreme in a warmer climate. As I write the prime researcher of our central res instit (KNMI), asked about AR5on prime time telly, mentioned that we here get more often "soaking" wet in summer in future.

Ken

It is climate forecast NOT weather forecast. The anecdote of the KNMI-er was because the moment I was replying to you he appeared on prime-time TV. In another setting I know him of course better as the head of the global climate division working with a large team on improving climate models by incorporating feedbacks with biota as an example. Apart form that there is the regional climate division of KNMI trying to incorporate especially rainfall into a regional climate model. That model is based on the current regional weather forecast model.

I have the impression that you have NO IDEA about the efforts made, by very talented scientists, to steadily improve the models. That is a very cumbersome work and the money given the very long times involved for such calculations.

Apart form these model efforts there are KNM-ers specialized in clouds working at the European weather center at Reading. Also at Delft University there is a group working on detailed cloud modeling.

Heavy rain is of special interest here in Holland because it has to pumped out (the west of our country does not have natural drainage). This is the reason many "water boards" are interested and actively involved in the current research on water management and projections of rain extremes:

Even in a country like ours there is a large spatial difference in rain intensity goin from coast to say 100 km inland depending on season. That is the effect of the proximity of sea and ocean.

I do not see why you are so bantering on model efforts

Ken

Weather and climate are very complex systems and a model is always an abstraction.

Weather forecast has very remarkedly (been) improved today as compared to 50 years ago in the sense that the present forecast for day 5 has he same score as that of the next day half a century ago.

Climate models that forecast the last 15 years date back to 20 ears ago and the next generation model does incorporate the present "standstiil" reflected in a lower climate sensitivity in IPCC AR5 as compared to that in AR4. What else do you want?

Harry, there are no models showing the hiatus at any reasonable confidence level that I am aware of. See von Storch survey from august this year. http://www.academia.edu/4210419/Can_climate_models_explain_the_recent_stagnation_in_global_warming

von Storch writes: "In recent years, the increase in near-surface global annual mean temperatures has emerged as considerably smaller than many had expected. We investigate whether this can be explained by contemporary climate change scenarios. In contrast to earlier analyses for a ten-year period that indicated consistency between models and observations at the 5% confidence level, we find that the continued warming stagnation over fifteen years, from 1998 -2012, is no longer consistent with model projections even at the 2% confidence level."

And there is no surprise if models can show the hiatus in hindcasting. That´s because they can be tuned to do just that!

Jan

In a way I would agree with you but I'll await the AR5 report. At present only the draft SMP can be read and there the stagnation has already been taken into account it seems by lowering the climate sensitivity compared to AR4

Ken

Climate is a long-perios average and thus it is not without sense that the climate sensitivity does not change much over ONE climate period of 30 years. To see changes one needs at least several climate periods of that duration.

Most of the climate scinetists I know are reliable and bright scientists that do their best. Mind you one climate run may take up to ONE actual year of computer-calculation. So modeling is a very tedious job.

It is very easy to stand at the side-line as a bright man like you are and criticise the obvious, but it does not help much in having some idea of the future. Again in the case of my country there is need to know sea-level rise and water-levels in general becasue we cannot wait and see what can occur but have to be prepared what might occur with given likeliness

Ken

I certainly looked at the graph of pop and CO2; so you basically have the same political message as IPCC. However I do hope we get to know where all the heat has gone lately, with or without models; when it is hidden in the ocean "d like to see more attention to search for it. As an experimentalist myself I know well we need models but I never have the illusion they are reality and they certainly cannot do without data.

Ken says: "If I were you I would go ahead and have faith in these models and be prepared for the worst."

But, I ask: What is the worst? An increase of CO2 that is certainly increasing greening in semiarid areas and the increase in sea level, which follows the same trends of tide gauges measures 200 years: or cooling, which certainly lead to loss of production grains in countries like Canada: U.S., Russia and China?

Maybe the worst is the second scenario!

Rogerio

What is the probability of cooling?

Ken

My question was on the entry of Rogerio

"..or cooling, which certainly lead to loss of production grains in countries like Canada: U.S., Russia and China?

Maybe the worst is the second scenario!"

Dear Harry.

If we consider a glacial period one with a temperature of -3 ° C than those of today (as glaciologists think) and if we consider the results of the piston and cores Vostok and EPICA, we should already be at the edge of a new ice age. Now if we consider a decrease of -1.5 º C, which would be a disaster, we welcome the greenhouse gases!

Rogerio

Please read the reply of dr (Kenneth) Towe. The probability of a new glacial within the next decades is of course zilch

I have writen and documented and detailed described that, and discovered the mechanisms involved

https://www.researchgate.net/profile/Dimis_Poulos

Hi all, you may be interested to see a new book, which came out of a large and long international research collaboration, funded by an EU COST action. The book is called 'Earth's climate response to a changing Sun' and considers the spectrum of solar-terrestrial mechanisms and evidence from an interdisciplinary approach. I highly recommend it for anyone seriously interested in the subject!

http://www.realclimate.org/index.php/archives/category/communicating-climate/skeptics/

First I want to invite to read documents quietly and make ideas from information. I am not a climatologist. But changing sources, I believe Hansen, for instance, was pretty convincing in some of his works. I remind that he did some forecasting year ago, about what caused climate change, against one of the famous skeptics. It looks likes that his forecast after a decade or so where correct.  Dear Kenneth, what yourself want to support? That CO2 does not influenced climate ? 

Ken

Single months / years are not climate

Show us where the hiatus is: not even Judith Currie, the most outspoken skeptical climatologist does not hold this opinion (anymore)

Ken

Who are the "everyone" accepting the hiatus: the provide those names or start with ONE meteorologist or climatologist

correction: the should read then

The quality of meteorological data is monotonously decreasing since 1969, see article for details.

Article Extraction of the global absolute temperature for Northern H...

Ken

I am not a native speaker but is the term used by Nieves

"slow down" the same as a hiatus?!

And a mere clipping is NOT science: where is this Karl-clipping clipped from, what year, what is the context

and then again: climate is long-term average weather not a fluke in a single year and specifically not a projected year as in your green sentence

In a scientific discussion one cannot merely show some sentences. The other party has no idea where this cherry-picking comes from and has no means to read fro him/herself

Summarizing: go to a blog like that of Judith Curry and there you find a discussion plus references on the last 15 years of global temperature. For a trend or a change this period is too short and suffers from variations in all kinds of synoptic weather patterns and oceanic oscillations

Ken

Indeed. Clippings are no science and it is even less science to ask from ME where YOU have these clippings from.

I gave you the link to the blog of the most prominent skepticist / meteorologist (Judith Curry) but obviously you do not read it  

Ken,

I agree with Harry. And I am not prepared to waste my time working out where your confusion arises. You have cited a newspaper, the New York Times. How do I get access to their old issues to read the full article? Moreover, they are quoting real science from a leading international peer reviewed journal. Which Science paper is the NTY quoting from?

If you want us to believe what you say, then you have to cite peer reviewed journals, not the bits from newspaper reports which fit your agenda.

Ken

You keep repeating yourself

WHERE is the reference for the 2 sentences you clipped from Judie Curry?

Where did you clip it from? Is this all she has to say about this item? only these 2 sentences?

And what about the clipping from Hansen in 1995? Is this about the hiatus?

And what do I care how you call Hansen