tantalus

You are misusing the information in the reference you listed, coming to conclusions beyond the certainty the references assert. A little bit of information is a dangerous thing.

 

Those of us with a science background have the skills to check the validity of the IPCC research/reports, and know that they are scientifically valid. Unfortunately, these skills come at minimum an undergraduate degree, but for most at the graduate level. This makes it easy for politically motivated groups to sway uninformed or misinformed people. When over half of Americans fail to learn algebra, statistics is way beyond their grasp.

You'll need to be more specific.

Also please don't make assumptions about my education and use argument from authority.

My impression was that the pendulum had definitely swung the other way. Do you have any citations to review articles that would confirm your thinking.

Not an easy thing to cite. Not really sure that there is any consensus building centre you can go to for evolutionary biology, after all, your looking for an academic pulse. There is definitely still plenty of disagreement. However, I would definitely agree with MEC1960 that the gene centred view dominates the academic field and is the most influential, but to get a feel for it I think you just have to read widely.

The thing is the distinction is not strictly important in many instances when discussing adaptations or explaining evolutionary causes of most biological phenomena, so that it can allow the debate to simmer or be left untouched in much evolutionary work.

I'm not, actually. I know from other sources that the changes in climate elsewhere, as a result of whatever happened in the North Atlantic, were much smaller and much slower

 

The evidence I posted up contradicts you, with the exception that the term "much smaller" allows for a wide interpretation. The younder dryas was a period of climate change far more significant that climate change of the 20th century. I won't discuss it terms of potential future change as it's a comparison to 20th century and extinction rates that is relevant to the original point of contention.

If you read your link there carefully, you will find that the dramatic effects described were large and sudden only locally - in the North Atlantic near Greenland. Although there were measurable global effects from that, they were much smaller and slower.

Your being selective. The ice cores are in greenland, so the best data will be there, while the greatest changes were there doesnt mean in wasnt very large elsewhere. edit. You will always get dramatic regional differences with climate change, if the IPCC more severe predictions are correct, we should expect more dramatic shift in certain regions over others.

Might the change have been restricted to parts of the world near Greenland? The first hints of the answer came from oceanographers, who had been hunting out seabed zones where bioturbation by burrowing worms did not smear any record of rapid change. In some places the sediments accumulated very rapidly, while in others, the sea water lacked enough oxygen to sustain life. The first results, from the Norwegian Sea in 1992, confirmed that the abrupt changes seen in Greenland ice cores were not confined to Greenland alone. Later work on seabed cores from the California coast to the Arabian Sea, and on chemical changes recorded in cave stalagmites from Switzerland to China, confirmed that the oscillations found in the Greenland ice had been felt throughout the Northern Hemisphere. Changes in dustiness were meanwhile noted in the ice itself, indicating at least continental scope for the change; later, a hemisphere-wide Younger Dryas temperature step in less than a decade was confirmed by a step change in the methane gas in the ice.(57) Meanwhile, in the late 1980s and early 1990s, improved carbon-14 techniques gave the first accurate dates for sediments containing pollen and other carbon-bearing materials at locations ranging from Japan to Tierra del Fuego. Good dates finally allowed correlation of many geological records with the Greenland ice. The results suggested that the Younger Dryas events had affected climates, one way or another, around the world. The extent and nature of the perturbation was controversial. But scientists were increasingly persuaded that abrupt climate shifts could have global scope, even if they affected different places differently — colder here and warmer there, wetter here and drier there.

 

https://www.aip.org/history/climate/rapid.htm

The Europeans and Americans nevertheless agreed that through most of the last 100,000 years the global climate had oscillated "on a scale that human cultural and industrial activities have not yet faced."

 

Same article.

This the the main report you'll fing on abrupt climate change with a case study on the younger dryas

http://www.nap.edu/read/10136/chapter/4#27

Beginning immediately after the main warming in Greenland (by less than or equal to 30 years), methane rose by 50 percent over about a century; this increase included tropical and high-latitude sources

Ice cores from other sites, including Baffin Island, Canada (Fisher et al., 1995), Huascaran, Peru (Thompson et al., 1995), and Sajama, Bolivia (Thompson et al., 1998), show evidence of a late-glacial reversal that is probably the Younger Dryas although the age control for these cores is not as accurate as for cores from the large ice sheets.

 

The ice-core records demonstrate that much of the earth was affected simultaneously by the Younger Dryas, typically with cold, dry, windy con-ditions. However, those records do not provide much spatial detail, nor do they sample the whole earth. For those, one must consider a global array of data sources of various types, as described in the following subsections.

The Younger Dryas was first discovered by studying the biological records found in terrestrial sediments. These records clearly reveal the global reach of the event. Owing to dating uncertainties, including those associated with the conversion of radiocarbon measurements to calendar years, the phasing of events between different locations is not known exactly. The ice cores show that much of the world must have changed nearly simultaneously to yield the observed changes in methane, Asian dust, and Greenland conditions, but we cannot say with confidence whether all events were simultaneous or some were sequential.

See link for northern hemisphere pollen evidence of change in ecosystems and species shifts. Also see link for far greater coverage of proxy evidence of the younger dryas event than I present.

Marine evidence of the Younger Dryas event is recorded as an interval of increased upwelling or decreased riverine runoff from adjacent South American land in a core from the Cariaco Basin in the Caribbean (Hughen et al., 1996, 2000a,b; Peterson et al., 2000) (Figure 2.4). Terrestrial evidence is primarily from three sites (Leyden, 1995). Evidence indicates a temperature decline of 1.5-2.5°C during deglaciation, probably correlated with the Younger Dryas,

Alley and Clark (1999) reviewed evidence from several marine cores that show warmth during the Younger Dyras in the southern Atlantic and Indian Oceans, opposite to most global anomalies but consistent with the warmth indicated in most Antarctic ice cores at that time

Overall, the available data indicate that the Younger Dryas was a strong event with a global footprint. Available data are not sufficient to identify the climate anomaly everywhere, and further understanding almost certainly will require more data. Different paleoclimatic recorders respond to different aspects of the climate system with different time resolution, so it is not surprising that the picture is not perfectly clear. Broadly, however, the Younger Dryas was a cold, dry, and windy time in much of the world although with locally wetter regions probably linked to storm-track shifts. The far southern Atlantic and many regions downwind in the southern Indian Ocean and Antarctica were warm during the Younger Dryas. Changes probably were largest around the North Atlantic and probably included reduced export of North Atlantic deep water. Changes into and especially out of the event were very rapid.

 

. At the same time, the resources and capabilities of wild animals have been much reduced by human usurption -they have much less room to move, fewer options for response.

I agree with this in principle

[mp][/mp]

But there are fewer species confined to just those regions, so of course extinction events would be reduced as opposed to global events.

Hopefully now I have illustrated it was much more than that.

You will find a lot discussion that younger dryas was linked to megafaunal extinction especially in north america, I don't find this overly compelling( as a key driver) for a variety of reasons that I rather not get into at length, but suffice to say it it has its advocates in the literature and it has to be given serious consideration.

Either way, there is no comparison with current extinction rates.

 

Northern latitudes. Younger Dryas was not global.

In western Europe and Greenland, the Younger Dryas is a well-defined synchronous cool period.^[34] But cooling in the tropical North Atlantic may have preceded this by a few hundred years; South America shows a less well defined initiation but a sharp termination. The Antarctic Cold Reversal appears to have started a thousand years before the Younger Dryas, and has no clearly defined start or end; Peter Huybers has argued that there is fair confidence in the absence of the Younger Dryas in Antarctica, New Zealandand parts of Oceania.^[35] Timing of the tropical counterpart to the Younger Dryas – the Deglaciation Climate Reversal (DCR) – is difficult to establish as low latitude ice core records generally lack independent dating over this interval. An example of this is the Sajama ice core (Bolivia), for which the timing of the DCR has been pinned to that of the GISP2 ice core record (central Greenland). Climatic change in the central Andes during the DCR, however, was significant and characterized by a shift to much wetter, and likely colder, conditions.^[36] The magnitude and abruptness of these changes would suggest that low latitude climate did not respond passively during the YD/DCR.

 

https://en.wikipedia.org/wiki/Younger_Dryas

With such dramatic changes in northern latitudes we can expect global effects. Cooler, warmer, wetter, drier, it all has effects on species locally adapted to past conditions.

Furthermore at a local and regional level a species can't make a distinction.

Ocean and lake sediment data from places such as California, Venezuela, and Antarctica have confirmed that these sudden climate changes affected not just Greenland, but the entire world. During the past 110,000 years, there have been at least 20 such abrupt climate changes. Only one period of stable climate has existed during the past 110,000 years--the 11,000 years of modern climate (the "Holocene" era). "Normal" climate for Earth is the climate of sudden extreme jumps--like a light switch flicking on and off.

 

http://www.wunderground.com/resources/climate/abruptclimate.asp?MR=1

These climate events have not been able to match mankind in the 20th century for causing extinction despite their scale and rapid onset.

[mp][/mp]

In fact, some argue that there havnt been extinction rates witnessed on earth since the cretaceous extinction event.

Also to add to my previous post, we should expect a bias to reported effects to major climate events to regions that have ice cores as they make such a good proxy for recording shifts in climate.

We must be careful here. The idea of fitness has been debated for a long time with it (very roughly) boiling down to two concepts, one championed by Gould and Eldrege (via G.G. Simpson and others) and the other by Richard Dawkins, W.D. Hamilton and others. The Gouldians (if I may) argued that an individuals reproductive success is selected based on a variety of traits, such as the tendency to engage in "risky behaviors" cited above. However, the dominant idea today is that it is not individuals that are the unit of selection, it is the genes themselves.

Agreed, care is needed.

Fitness was a term developed in the academic period that championed the individual as the unit of selection. The gene centric view doesn't dismiss the individual but co-opted it, and with the concept of the gene as a unit for selection was able to provide an even better explanation for many difficult evolutionary conundrums. Yet genes still come together to build bodies, and largely they succeed or fail together (allowing us to get away with not making your distinction), so evolutionary fitness of that collective of genes is still a relevant concept.

Even if it useful to think in terms of success/fitness for the genes that code for risky behaviours.

 

I don't find the excuse of "it might not have been climate change" to be very compelling. Fracking a species to death (as an example) is not any kind of improvement.

 

And to use "so far" as a benchmark, I'll just ask — is there anyone out there making the case that it's going to get better?

 

 

No i doubt it. But basically what I am saying is climate change is linked to only a handful of extinctions in the last 100 years, extraordinary high extinctions rates have been driven by other players and we are likely to see the continuation of that pattern.

 

And of course you can point to previous instances of climate change as abrupt as this.

 

No?

 

Then that's a moot point.

 

Abrupt is a relative term. Regionally you can look at the medieval optimuum 950-1100 and the little ice age, cool periods in the 1600, 1700 and 1800s punctuated by warming periods.

Dramatic abrupt changes have occured regularly (over 20) over the last 100,000 years with events where proxy records indicate 5, 10 degree jumps in years and decade time periods.

One example is the youner dryas, a 2-6 degree celsius drop in northern latitudes in decades.

https://en.wikipedia.org/wiki/Younger_Dryas

These events are not punctuated by rates of extinction that we are currently witnessing.

 

Why are they already endangered, though? This sounds like "we've already screwed them most of the way. Why not finish the job?"

 

No, was pointing out that climate change is likely to be more important that in the past because species are so vulnerable.

 

People are already concerned with habitat loss. That's an issue of political will. But there's probably a pretty good overlap of people who don't care about habitat preservation and those who sit on their hands when global warming is the action item.

 

It's more than political will, there is a fundamental problem with increasing world population and seeking to raise living standards for everyone and still wanting to preserve the habitat, but I take your point.

As research progresses, sentience is not limited to humans.

For sure, but big picture, not relevant to most species on the planet

What about all of the other species that cannot adapt? Do we not have an obligation to take all life on earth into account, not just us?

Depends on your value system, the intrinsic value of non-sentient life is a tough sell to many. Species and ecosystems have monetary values that are dramatically underestimated by the free market, an economic and functional based argument is a more productive avenue imo.

Tantalus, if you won't accept that climate modelling is a valid way to figure the possible and likely consequence of emissions,

No, climate modelling is a valid scientific method. The way the IPCC portray that body of work and the state of that science in their summaries is when much of the problem emerges.

how do you think we should make some kind of judgement and proceed?....

 

....Taking no actions until we know better is in reality continuing to take strong actions - gigatonnes a year of fossil fuel burning - on the basis that we just don't know.

First, it's a logically sound principle to take preemptive action without certainty.

Assessing action is very complicated and requires the input of scientists, economists, politicians from a wide range of fields, and their findings will vary locally and regionally. We should assume that the specific outcomes of their work are significantly effected depending on the amount of warming that occurs or our assessment of such certainty, and or the perception that takes hold from the IPCC reports.

In light of such a complex process, I will give you a tepid response and it should be judged as such, not in absolutes.

It's also worth noting that certain measures have other reasons to be undertaken anyway, consider the problems the Chinese face with air pollution relating to coal, even without factoring in their carbon emissions.

I think we should focus on carbon-emission efficient technologies, climate adaption, especially in poorer countries, correct a mistake I think we made decades ago, and refocus on nuclear (especially over coal), while resisting calls for rapid reductions in carbon emissions that would damage growth, or the employment of expensive carbon sequestration proposals.

Climate adaption is the key and a sound investment, needs to be applied at a local and regional level and possess many benefits other than to counter man made climate change effects. In fact, they would also protect against natural climate change, decadal variability, extreme weather events. And align with many other solutions to other environmental problems such as flood plain management, habitat loss, soil erosion etc

A particular focus will be needed on global food security and preventing fluctuations in key commodities prices. The free-market is very sensitive and there is potential of quickly seeing millions being unable to afford food, and many rapidly sliding back into poverty.

 

To what extent should your personal doubts be grounds for withholding acceptance of the professional work of others - work that National Academies and Meteorological organistions consider valid? And to what extent should that withheld acceptance be the basis in turn of political opposition to policy that treats the mainstream advice as valid?

I find the second last question is oddly framed, nobody should be including someone like me in a framework for policy formation, but that's not to say my opinions shouldn't be included.

On your last question, naturally I feel my opinions have a sound basis and should be included in political opposition as necessary.

There is something worth mentioning not related to policy, the conduct of science. I feel that the scientific process is being damaged. Since advocating policy is needed in some form, and funding is required, there is an unavoidable link between politics and science.

However the language of politics has rapidly crossed back into the field of science, any debate of IPCC work now is often being shot down with political language, and this is not in the spirit of the scientific process.

 

So how does that call into question the consensus on warming? We know we're in a middle-of-the-road scenario, and we see warming — none of that is challenged by what was said. The question is about how severe it will be, and how accurately we need to predict that. But you won't/can't constructively engage on that.

I misused the Brown paper, so it has little impact on a consensus on warming from what I think you mean by that.

Please note that its not a consensus on warming that is in question, well I suppose for the last 15 years there clearly is debate as underestimated volcanic aerosols or natural variability linked to long term climate cycles not included in models, or heat storage, or problems with model sensitivity et al. may be offsetting co2 increases, but long term we should absolutely see warming, the question is how much. And if the IPCC conveys the state of the science and certainty when they represent the modelling results they collate, actually more that do they convey the state of their own collected science in their summaries.

This is achieved in part by reasoning the evidence, for example expert judgement of the uncertainties in modelling results, not just looking at the graphs of actual models and their error bars. Those kinds of uncertainties in the models are absurdly complicated to a layperson, you can only yield to expert opinion. I don't think IPCC summaries are an accurate reflection based on the views of others.

I have tried to present on the this idea of an extension of the consensus that extends through to confidence in the IPCC models as reflected in their summary.

 

I'm pretty sure you've misread it. The passage talks about albedo and insolation of Northern Hemisphere in which the biggest driver is glaciation in high latitudes. Increase or decrease in the amount of glaciation changes the insolation regime of the whole hemisphere by a lot.

Ya I miss understood that. Thanks

 

I don't think that's so. What he's implying is if the worst case scenarios had held, we wouldn't have had this so-called hiatus for the length of time we saw.

Yes, I would agree on that's what he is saying.

Its long been known that the Sahara was a green temperate grassland until 5 to 6 thousand years go. More recent evidence indicates that it abruptly changed to desert in 1 to 2 centuries. The cause of the wet, green sahara was linked to changes in earth's tilt and rotation that affected the sun's radiation in the region, triggering monsoon rains that swept onto the continent.

The fact that the change from desert to grassland occurred so quickly indicated additional feedbacks, because the change with the sun couldnt cause it so quickly (apparently), the below paper speculated on an a further feedback by the growth of vegetation in the formerly desert region that sped up the process and they modelled it.

Simulations with a synchronously coupled atmosphere–ocean–vegetation model show that changes in vegetation cover during the mid-Holocene, some 6000 years ago, modify and amplify the climate system response to an enhanced seasonal cycle of solar insolation in the Northern Hemisphere both directly (primarily through the changes in surface albedo) and indirectly (through changes in oceanic temperature, sea-ice cover, and oceanic circulation). The model results indicate strong synergistic effects of changes in vegetation cover, ocean temperature, and sea ice at boreal latitudes, but in the subtropics, the atmosphere–vegetation feedback is most important.

 

http://science.sciencemag.org/content/280/5371/1916.full

so it discusses your albedo effect.

I guess this indicates on a large enough scale the importance of vegetation under this alternative climate scenario, but note the change in rainfall patterns came first.

I cant see how you could plant trees in a desert like the Sahara currently on a large scale that could have any significant impact without a change in rainfall patterns that would keep them alive.

Anyway, it is possibly rainfall that constrains tree growth in the sahel, and even in the savanna further south in favour of grasses that can outcompete tree seedlings in lower rainfall ecosystems, so you would have a better chance with grasses initially, although now I am just becoming a little speculative to say the least.

I was thinking about some type of greenhouse that could collect the water but it is too expensive to make one, using plants with atmospheric water generators could be much easier when there are new technologies, for now atmospheric water generators are too expensive to large scale production

I have heard of design projects in Africa which seek to prevent water escaping greenhouses and trapping and reusing it. Not sure what there energy efficiency would be like, and I can't find reference to them online.

Did come across this simple design in Ethiophia

http://www.roots-up.org/#!Design-of-a-Dew-collector-Greenhouse/c1j2v/55082c6a0cf2031a76490f16

By raising the temperature in the day (I assume the plants they grow must have very high tolerance to high temperatures) they increase evaporation, which increases humidity, as hot air holds more water, the increasing humidity means even more water vapour is present than at lower temperatures, they then lower the temperature at night by removing the roof, the quick drop in temperature leads to condensation on the film (cool air cant hold all that water vapour so it condenses), and into a water container.

Clean, usable for drinking or irrigation. It is not clear to me how much of that collected water came from plant transpiration versus evaporation, and would obviously depend on the amount of plant matter, species etc.

Another project using a dessicant in the UAE. Although I have to say I don't understand the process as described in the article

http://www.thenational.ae/uae/environment/20150914/greenhouse-that-could-save-uae-farmers-90-per-cent-on-water-unveiled

 

So you have no target in mind, which is convenient. NO model is 100% accurate. So even though you agree this is important, having no value in mind gives you leave to take potshots at the efforts and call them inaccurate, but leaves you with no accountability in the discussion at all, because there is no way to be 100% accurate. So even if they end up nailing something to 0.01ºC, you (and others) can still call them inaccurate, even though that level of accuracy is not needed to inform us of what's going to happen.

 

And this has implications about consensus and whether they are broadly agreeing or disagreeing.

No body expects them to be 100% accurate. I don't have the expertise to give you numbers, I would be wasting your time.

In the observations, what factor or factors have contributed to the stasis in tropospheric and surface warming and why are the tropospheric temperature trends in CMIP5 models, on average, larger than those observed over the stasis period?

 

From Page 211 of the transcript, Santers presentation.

Now while he is acknowledging the models difficulty, he goes on to propose a series of potential explanations for the stasis and models difficulty, and he doesnt feel they threaten the over all picture, so you can read those in the few pages that follow 211.

Curry states that in regard to the hiatus that

Only 2% of climate model simulations produce trends within the observational uncertainty

 

http://judithcurry.com/2014/03/04/causes-and-implications-of-the-pause/

I don't understand your position, even IPCC scientists like Collins and Santer acknowledge model failures over the last 15 years in regard to the hiatus. The real issue is the significance, if any, of such problems.

In addition, since only time can confirm the merits of current modelling, discussions must be had not just in relation to the hiatus, which may not be very significant, but on the theoretical element of the models, and the level of uncertainty within them. The transcripts convey this debate well, although I havent read all of it yet (still need to read Isaac Held and concluding questions/discussion sections).

 

But that's not what Brown meant, which is clear by the article (or I assume so; I can't get to the sciencedaily page but they just repost stuff anyway) I looked at this:

 

http://www.accuweather.com/en/weather-blogs/climatechange/middleoftheroad-warming-scenar/46028133

 

This clearly shows they are comparing to the A and B family of scenarios. Not models.

 

But your point has nothing to do with my point, or Brown's quote.

 

No, I am even more confused

Short version: it doesn't matter much which of the models you pick, if you have used a scenario with a rise in CO2 of 100% vs the actual rise of 50%, you are going to end up with a larger temperature increase in the former case than in the latter CO2 is a positive forcing,

 

None of the recent IPCC models deviate in co2 emissions until later into the century, therefore they can't effect the initial point of discussion, the recent hiatus.

[mp][/mp]

Ok I think I get one of your points now (I was slow on the uptake), Its actually unclear if Brown discusses solely A and B scenarios, or more at length about IPCC models, I think he is discussing both, although separately. You certainly can't discuss the recent hiatus in terms of scenarios, but actual models, but I think I see your actual point about what Brown is saying in regard to (only specifically in regard to) his "middle of the road" comment and the A, B scenarios.

I am definitely confused by your post. Also, I am not sure what page 265 refers to (the transcript?)

When I discuss scenarios, I'm really refering to how models handle sensitivity, and how that affects their predictions of future temperature rises, perhaps that is confusing others when they read my posts.

To quote your original post

But it's meaningless if one doesn't actually assess it. What are the "most severe IPCC projections"? Are we actually in a situation where the world is following that scenario, and yet temperatures are lower than projected? Without looking into that, throwing around quotes as if the mean something is pointless. Because the simplest answer is that we just aren't following the worst-case scenario.

 

My point is that the IPCC latest modelling efforts don't deviate until 2040 with different co2 emission scenarios. Current difficulties in matching recent surface temperatures are not linked to co2 emission scenarios. Obviously nobody will be stating models are wrong 80 years from now if the model in question ran a different co2 emission scenario than actually occurred.

 

 

I don't see where you have defined what level of accuracy you need when you claim that models are inaccurate. How accurate do they need to be?

Dont really no. IPCC have different modelled scenarios in regard to climate sensitivity, so which ones best fit real data as it comes in? And the state of expert opinion in regard to modelling failures to match real observations, and what, if anything, we can take from that over the short time periods in question.

Since we don't know what the temperatures are going to be, the discussion on uncertainties and limitations in the models to account for variables that affect climate sensitivity are very important.

The question is there a consensus among experts and what broadly are they disagreeing about and does this have implications in regard to certainty about different projections of climate sensitivity...

Swansont,

To further clarify

It is done by some models. But that misses the point.

Its not just some models and It does miss that point, because I was trying to address your original point in that specific instance, not the models in general. It does clarify your original post on narrow grounds, without extending the clarification to any impact on the merits of the models. Your original post suggesting changing emission scenarios in reality not matching modelled scenarios asa possible explanation for any divergence in recent years between modelled scenarios and surface temperature data.

To elaborate

The second source of uncertainty is what mankind is going to do. And we are not going to talk too much about that today. And the solutions on this graph don't really separate out until 2040 or so. Most of the climate change between now and 2040 is committed from historical emissions, about two-thirds of the common signal.

 

The graph relates to the 45 modelled scenarios the IPCC used in its latest report. Page 31.

Quote from Dr.Collins, lead author of latest IPCC report on model evaluation. From page 37

http://www.aps.org/policy/statements/upload/climate-seminar-transcript.pdf

To clarify, this specific point is only addressing your original post, not the merit of IPCC modelling in general (or ore correctly, their summaries).

Cool.

Merged post follows:

Here's the thing guys, the watt link is a report of a workshop by the American Physical society from 2014, the largest society of physicists and one that has an official statement from 2007 in line with the IPCC. Although they made some adjustments to that report.

That workshop was a discussion on climate modelling among others involving these 6 climate scientists.

http://www.aps.org/policy/statements/upload/climate-review-bios.pdf

the bios pulled from the APS website.

If you want a look at the bios, a look at the link, assess the expert opinion, it is informative of the state of the science and level of certainty on important issues. The transcripts are also available.

Interesting to note that the APS sub-committee chose these 6 after discussion with the society at large. They will use this document to form a new official statement that they hope is based on a consensus within the society. Currently their report on the workshop is not available to non-aps members until the process is complete, but it should be very interesting.

APS timeline in regard to workshop

http://www.aps.org/policy/statements/climate/index.cfm

APS thought process on workshop

As part of the process, the Review Subcommittee convened a workshop on Jan. 8, 2014, with six climate experts. “We used this meeting to delve deeply into aspects of the IPCC consensus view of the physical basis of climate science,” said Barletta. “The Review Subcommittee’s goal was to illuminate for itself, for the APS membership, and for the broader public both the certainties and boundaries of the current climate science understanding.”

 

http://www.aps.org/policy/statements/climate/article.cfm

This workshop represents serious discussion among experts, not fluffing by right wing media.

Acme et al.

On 15 year time spans, there needs to be a distinction between limitations and useless. A 15 year time span offers serious time limitations, but that doesn't mean it can't be instructive for debate while acknowledging important caveats. Note Dr.Collins, a lead author for IPCC and expert on modelling on the importance of the period extending out to 20 years...

“…if the hiatus is still going on as of the sixth IPCC report, that report is going to have a large burden on its shoulders walking in the door, because recent literature has shown that the chances of having a hiatus of 20 years are vanishingly small.”

 

Additional post.

Swansont.

I hope to convey the nature of the debate among experts in regard to IPCC modelling, so better to establish the level of certainty on future climate predictions as represented by the IPCC.

Additional note.

 

It doesn't have to be new science. Any science at all would suffice. But I don't see any. How can you evaluate the merit of someone's take, pro or con?

With very limited success I should think. The question for me is does the IPCC summaries mischaracterize the state of expert opinion on climate modelling and future predictions, and that it is being widely convoluted with an established consensus of climate change and the principal of carbon emissions having an effect.

 

And I have a problem seeing "two opposing sides" (again, this is a pop media tactic of implying both "sides" have some equivalence, and thus a controversy where none should exist). What I see is a consilience of the evidence provided by multiple disciplines acknowledged by all but a tiny fraction of professionals who study this, and some people who claim to be skeptical about it but focus on denying the consilience of evidence rather than refuting it.

 

What I also don't see is the courageous, out-of-the-box thinking, bright-minded skeptic who challenges accepted mainstream thought, and makes everyone see how right he is through the sheer force of his contradictory evidence. I keep seeing people who haven't studied this being manipulated by talking heads who haven't studied this, who are probably being paid to help stall any regulatory action, because profit is more important than a better environment to many.

Did you have a read through the brief Watt website report from last year's APS workshop I linked. I am interested to know if that had any effect on your view?

The problem is your confusing the consilience that brought about the definitive conclusion that the climate is changing and man is influencing that change through CO2 emissions with something different, the state of certainty on different modelled scenarios and the state of certainty that surrounds that specific field of science. It is a mistake to extend the former consensus into the latter, to convolute the two.

Alright, thanks guys

I'm not sure what the Admins have that function set to. It used to be 6 hours before your editing switched off (we had folks who abused editing). If you post again rather than editing your first within that time, it automatically merges the two.

Is it considered acceptable on the forum to add later posts that simply merge?

Under the scenario of whereby I have just posted on a thread, and I choose to post again soon, when it is still possible to edit the first post, the second post always gets added onto the end of the first post.

Is this the only way to post the second post, or can I post it separately?

I find I run the risk of having added onto it and someone having replied to it in the mean time, also I like to use multiple posts when replying to multiple members.

 

You say this bias affects scientific work "like anything else", but that's not true. "Anything else" doesn't have the same rigorous methodology available to resist exactly such subjective assessment. Bias may be available to all in equal measure, but in science we don't treat bias the way "anything else" does. We have taken measures to combat it that are extraordinary.

 

In regard to selection bias.

On this part of your comment, quite simply your right, what i said was not what I intended, and to be fair, I did twice make the point that the scientific process through peer review does sort out the problem with time, I agree, no where else in society can you find this.

So yes ultimately the effect isn't equivalent, just the opposite.

This is a pop-culture, media-driven argument, one that tries to make all sides of an argument equal to promote an alleged controversy, when they clearly are NOT.

 

The problem here is considering the matter with the distinction of only two opposing sides and nothing in between, those who deny climate change and those who agree with the IPCC's latest report.

It's Watt, so no, that's not adequate. He's glossing over quite a bit here. In the IPCC assessment (as shown in figure 10.4) you have adjustments both below and above 1. The average of all the models for CO2 is above 75%, so the statement that based on this temperatures are more than 25% overestimated is wrong. It also ignores that when the analysis is extended over a longer period and GHGs are combined instead of broken up, the adjustment average is about 0.98.

 

No, this is no what I intended to draw your attention to.The point was much smaller that I was trying to address. Only consider your very first point in the first post you made, about actual emissions possibly not matching modelled emission scenarios, at the workshop both sides acknowledge that this is done by the models in the near term and they discuss the merits of extending the method in the long term, (as in messing around with emission scenarios).

Also, it is not relevant that it is the Watt website, unless you actually think he lied about this particular point, which there would be no point in lying about.

I wasn't trying to evaluate the above comments.

 

A big problem here is that you haven't defined what level of accuracy you need when you say "models have failed to predict the last 15 years accurately" (I will echo what others have said that 15 years is too short of a scale to work with). Let's go with Watt's inflated 25% scaling. Does that imply that you think the models are inflated by 25% but otherwise (i.e. with the scaling included) can be considered accurate?

I have no idea. I am trying to establish if there are experts who disagree with current IPCC positions and present the general line/ summary of their thinking, but I can't actually evaluate the technical merit over the IPCC's. I have some layman understanding and I do the best I can with it.

Neither do I, but that's not what anybody has suggested discussing. Merely parroting what someone else wrote, though, isn't sufficient.

 

If you can't assess their work, how do you have any confidence they're right?

I am confused. You asked did I have any science to discuss? and started discussing models, error ranges etc. I can't do that. I have no new science to offer. I only have other people's quotes, their assessments.

Apply the last question to something not controversial, you use your best judgement. I don't have high confidence either way, but I have never been impressed with the idea that modelling the climate was going to be accurate given how complex it is.

If this was a non-policy issue, and not controversial, I would not be taking sides or more likely not paying attention, as the papers are published for decades between squabbling factions as they argue about the different climate variables and sensitivity, feedbacks etc

I think that debate has been ursurped by forces outside of the peer review process and that is unusual for science. Now those who question the science of the modelling are in danger of being associated with all skeptics.