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wili at 04:33 AM on 22 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
RH wrote: "Climate science is a very complex subject..." Very true if one is talking about the whole thing with all the details. But the essential elements are fairly straight forward (though I'd be more than happy to be corrected on any of them if I get something wrong):
1) CO2 is a greenhouse gas--it acts as a kind of blanket keeping heat from escaping into space; established some 150 years ago; very basic science.
2) We have dumped and we continue to dump lots of extra CO2 into the atmosphere, mostly from burning fossil fuels--coal, oil and methane. (Are we up to 38 billion tons CO2 a year now?)
3) Not surprisingly, given #2, concentrations of CO2 in the atmosphere have risen by about 40% since pre-industrial times: from about 280 parts per million to about 400 ppm now--we are making the
'blanket' much thicker.4) Also not surprising, given #s 1,2 and 3, global temperatures have increased by over .8 degrees C (about 1.5 F).
Those are the basics. And every step is (or should be) completely un-controversial and well established. Everything else is complications that those who don't understand the science should trust that scientists actually do know something about them. And they have pretty much all come to the same conclusion.
I think the mods got it right that 'Daniel' was trolling here, so he is not likely to be persuaded by anything anyone says. I don't know how one persuades people who are not really interested in being persuaded. But I think it is useful to lay out the bare essentials of the situation (as others also tried to do), since those are fairly straight forward.
But getting back to the Arctic and the 'pause'--We've lost something over 10,000 cubic kilometers of Arctic sea ice, most of it in the last 20 years. Wouldn't that change of state suck a lot of energy out of the system?
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Rob Honeycutt at 02:56 AM on 22 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Daniel... And really, do watch the Richard Alley video I posted earlier. You'll get a sense of both how complex the subject is and why scientists understand what they understand.
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Rob Honeycutt at 02:51 AM on 22 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Daniel... I have no way to determine your intent with these questions, but if you're going to come here with genuine questions about climate science, you can't take a stance of "scientist have to..."
There's a well understood aspect of science: It's true whether or not anyone likes the results.
Tom and Michael actually did a very good job of explaining the science, regardless of whether you appreciated their tone. They showed you very clearly what the research shows us. It's not required that you understand it, nor even that you read it, for it to be correct.
The reason I suggested that you go back and read some of the basic materials here on SkS is because you're asking very very elemental and antagonistic questions. You need to fully inform yourself first, before you have cause to state what scientists need to do.
Climate science is a very complex subject backed by 150 years of research consisting of well over 100,000 research papers, produced by over 30,000 scientists. When you come upon some aspect of the science you don't understand, look it up. Find out why scientists are saying what they're saying. And if you still don't understand, ask questions. SkS is a great place to find answers. But you don't even have to trust us. If you still don't understand something, see if you can find one of the actual climate researchers. Send them a polite email with your question. I've found they're usually eager to explain their field of research with those who are willing to listen.
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DSL at 01:41 AM on 22 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Daniel, just read one thing--one little piece: paleoclimatology. Understand that many of the same people who are supporting your claim of 4.5 billion years are also people working on climate. The information they produce is integrated into the overall understanding of Earth's climate. It seems ridiculous that you would assume 4.5 billion years and then claim that paleoclimatology has not informed study of the present day climate. It seems that way because to everyone posting here it is obvious that paleoclimatology is an integral part of the study of climate.
Also, if you want the science communicated to the general public more effectively (I assume you do, else why come here?), could you say a bit more about how you came to your current understanding of the study of climate, please? -
michael sweet at 22:53 PM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Daniel,
I simply pointed out the inconsistancy in your questions. If you find that rude, condescending, and insulting perhaps you need to ask better questions. When your posts are rude, condescending, and insulting people tend to reply in the same way. If you are polite you get polite answers.
For complete information to everyone reading, Daniels original post was deleted by a moderator for sloganeering. He reposted it and the new moderator has let it stand. If your posts are deleted that means you are not polite enough for this venue.
Moderator Response:[JH] I deleted Daniel's (posting as drebich) intital post because it was "off-topic sloganeering." If I had seen his repost of it before other commenters had responded to it, I would have deleted it again for the same reason. Concern trolls such as Daniel/drebich need to know that conformance with the SkS Comments Policy is not optional.
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Kevin C at 19:35 PM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Dear Daniel,
Let me try and explain the response to your question.
When my daughter was 3, she found an illustration of Isaac Newton sitting under and apple tree. "What's he doing?" she asked.
I replied "He's sitting under an apple tree. An apple has just fallen on his head. He says 'Why did that happen?'".
My daughter immediately answered "Because it was ready to eat!".
In a sense, she was right. The apple fell because it was ready to eat. But at the same time, she had completely missed the scientific point of the question. Why did the apple accelerate downwards at approximately 10m/s2?
When we try to talk about science in natural language, or worse, to think about science in social and ethical terms, we completely miss the point. And trying to do science in these terms leads to nonsense conclusions - a classic example would be the work of Gerald of Wales.
Similarly, when you ask 'what should the temperature be?', your language is a strange conflation of scientific and ethical concepts. Temperature is completely uninfluenced by moral imperatives. There is no 'should'. The fact that you can construct a grammatically valid question, does not mean that that question makes any sense.
So when you ask a scientist a question like this, they'll either look at you as though you have a fish in your ear, or assume you are trying to ask a different question, or assume you are playing dishonest word games. Unfortunately in this case there used to be a particularly annoying troll who used to ask the same kind question on every single climate discussion for several years, hence a more negative response than you were expecting.
So what question are you trying to ask? If I were to make a guess, then I'd put it something like this:
- What is our best understanding of the factors that control the temperature of the earth?
- What is the evidence for that understanding? How confident are we with respect to various influences?
- On the basis of that understanding, what do we expect to happen in future, given a particular action on our part?
- How will this affect us? Future generations?
- What should we do about it?
The first three of these are scientific questions. The fourth spans scientific, social and economic spheres. The final is a moral and political question. This website is concerned primarily with the scientific dimension.
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Jim Hunt at 18:53 PM on 21 February 2015A melting Arctic and weird weather: the plot thickens
In surprising news, there was another huge calving of the Jakobshavn glacier in West Greenland, of "Chasing Ice" fame, earlier this week:
Shock News – Massive Calving of Jakobshavn Isbræ
Although this is no longer the case today, the recent storms in the North Atlantic reduced Arctic sea ice extent to an all time record low for the date earlier this week:Shock News – IJIS Arctic Sea Ice Extent Lowest Ever!
Is there a feedback loop here? Less sea ice => more open water => bigger storms => more wind and waves => less sea ice?
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shoyemore at 18:31 PM on 21 February 2015A melting Arctic and weird weather: the plot thickens
arctic-outbreak-shatters-records-in-eastern-u-s-coldest-yet-to-come/
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Tom Curtis at 17:03 PM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
drebich @24:
1) You accuse me of being "rude, condescending, and insulting" because I correctly noted that your questions were nonsensical. They are nonsensical because you make assumptions in the framing of the questions that are simply false. Thus, you assume that there is a value for sea ice extent such that if sea ice extent is greater than that, that implies we are heading for an ice age, while if lower we have strong anthropogenic. There is no such value. Pointing out that the question is nonsensical is no insult unless your value as a person lies entirely in your possessing, or not possessing, the relevant specialist knowledge. Put simply, you asked "bullshit questions" because you do not know enough on the topic. In that context, the only correct response to to point out that they are bullshit questions, and why (as I have done).
However, as you raise the topic of rudeness, just how polite do you consider these comments:
- "I cannot help the fact that "Man Made" Climate Change Scientists come across (to me) as being quite intellectually arrogant"
- "it just comes across as almost unintelligent to think that man could possibly have any influence at all"?
They strike me as being very rude, and hence your concern about your own percieved slights as more than a little hypocritical.
2) Even more hypocritical is your response to my explaining why your questions are nonsensical. You write:
"The earth is approximately 4.5 Billion years old (and I would have to take an un-educated assumption that it may not be in it's final state), yet you post your charts and graphs and reference the last 10,000 years (or even the last 200 yrs)."
Yet each of your three questions required a single value of a variable assessable now. So a single years data (or at most a decade) according to your questions is all the information you need. But when presented with far more than that - it is not enough because of the tremendously long history of the Earth. From this inconsistency, that only a years data is purportedly enough but much more than a years data is rejected as not enough, it looks very much like your questions are a con. That is, your intent is entirely rhetorical.
Well, I guess we knew that already, given the way you framed your third question.
That impression is further reinforced by your strawman fallacies ("the planet earth is in it's final state"), and your assumptions about what I base my views on (hint, it is not solely the data I considered relevant to your specific questions).
3) Finally, you seem to think the geothermal heat from "the big blob of molten rock that we are floating on" has more impact than CO2. In that you are wrong. That is one of the many factors of climate that climate scientists have analyzed but spend little time talking about because it is inconsequential. Of course, some aspects of the Earth have major consequences for climate. The presence of a land mass over the South Pole, entirely surrounded by water; the existence of extensive continuous land masses in the Northern Hemisphere from 30 - 66 degrees latitude; the lack of a channel between the tropical Pacific and tropical Atlantic, or tropical Atlantic and tropical Indian Oceans; even the rate at which the African continent is moving north - these all have very large effects on the current climate state. Climate scientists, however, spend little time talking about them publicly because in terms of change in climate over a few centuries, they are essentially fixed features and have no effect on that time scale (however large an effect they have over 100 of thousands to millions of years).
Finally, it is a waste of our time to try and answer the questions of a person too ignorant to ask sensible questions, and too arrogant to recognize that is the case. Certainly such a person will never be convinced no matter what our answer.
Moderator Response:[PS] Tom, please stick to answering the science - you are very good at that. This comment is at limit of civility and only stands because I do agree with the sentiment and can only hope drebich will bother to learn enough to ask sensible questions in future.
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Glenn Tamblyn at 16:53 PM on 21 February 2015Models are unreliable
sangfroid
"Most scientists do not understand randomness and the role it plays in all aspects of our lives"
Excuse me while I pick my jaw up of the floor!
Understanding of 'randomness' is absolutely central to science. I would back 100 scientist's understanding of statistics against 100n people from just about any other background - apart perhaps from pure statisticians.
So your comment "Weather - despite how much we think we understand the interactions of everything that affects weather - is totally random" betrays a deep limitation in your understanding of both weather and statistics.
Weather is an example of bounded randomness. A process that displays degrees of randomness, but within bounds imposed by non-random processes. Primarily the Conservation Laws. Randomness for example could never produce high pressure systems over the entire planet - the Law of Conservation of Energy prohibits that.
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drebich at 16:18 PM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Thank you Rob Honeycutt, your reply was very polite and not condescending in any way. I truly appreciate that.
As for Tom Curtis and Michael Sweet, not only were your replies rude, condescending, and insulting, they simply didn't answer any of my questions. The earth is approximately 4.5 Billion years old (and I would have to take an un-educated assumption that it may not be in it's final state), yet you post your charts and graphs and reference the last 10,000 years (or even the last 200 yrs).
As a Scientist, do you actually feel comfortable using such a miniscule segment of time for your conclusion, totally disregarding the immense changes that this planet continues to exibit? Are you telling me that you alone have decided that the planet earth is in it's final state. That the big blob of molten rock that we are floating on has absolutely no impact on climate change, or our CO2 emissions have more affect on the planet than the huge blob of molten rock?
And Michael, I used the term "Man Made Global Warming" in order to distinquish between "Global Warming" which many people do believe is happening.
Guys, I know this is beneath you, but these questions may be very important for you to be able to answer if your goal is to convince an uneducated majority to accept your findings and predictions. I'm not asking these questions to get under your skin, I'm asking them to see if you have answers, none of which either of you have been able to deliver on.
Best Regards,
Daniel
Moderator Response:[PS] Daniel, please, please, please read the actual basics of the science you are questioning. Extremely uninformed questions that attack the science does not help and results in poor responses. Start with the "arguments" link top left and if you have issues with the explanations there, comment in the appropriate place. Simply repeating tired old arguments like "climate has changed before" or "it's geothermal heat" without evidence to support them is sloganeering and will be deleted.
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meher engineer at 15:53 PM on 21 February 2015A melting Arctic and weird weather: the plot thickens
RE Hank # 3, the Laird paper is cited by Cook et al in "Megadroughts in North America: placing IPCC projections of hydroclimatic change in along-term palaeoclimate context" (http://www.ldeo.columbia.edu/res/div/ocp/pub/cook/2009_Cook_IPCC_paleo-drought.pdf.
Global warming will expand the worlds dry lands polewards and make them drier: the IPCC AR4 Report said so and it makes sense.
The Cook paper is mostly about model projections. It didn't say anything about a connection between past Mega droughts and the Jet Stream. Not surprising considering how little we understand the Jet Stream.
It did say that the past megadroughts were connected to changes in solar activity (see this quote from the Conclusions: "There is no question now that profound megadroughts have occurred in North America during the last millennium, principally during MCA times and into the early part of the Little Ice Age. These droughts have occurred without any need
for enhanced radiative forcing due to anthropogenic greenhouse
gas forcing. There are additional model-based results suggesting that the MCA megadroughts were associated with enhanced warming during a time of increased solar irradiance."" Nothing was said about the changes affecting the Jet Stream? -
Tom Dayton at 15:35 PM on 21 February 2015Models are unreliable
Sangfroid, you wrote "Most scientists do not understand randomness and the role it plays in all aspects of our lives. We exist totally due to randomness."
You are wrong on both counts. For example, biological evolution is not "totally random."
Regarding weather versus climate, see the post "The difference between weather and climate." After you read the Basic tabbed pane, click the Intermediate tab.
See also "Chaos theory and global warming: can climate be predicted?" which has Basic and Intermediate tabbed panes. And "The chaos of confusing the concepts."
If after that you still believe most scientists do not understand randomness, read the seven-part series "Natural Variability and Chaos" at ScienceOfDoom.
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Stephen Baines at 15:07 PM on 21 February 2015Models are unreliable
typos!
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Stephen Baines at 15:06 PM on 21 February 2015Models are unreliable
Tom's
That answer is spot on. I have to write that down. I think its worth reemphasizing that the models do not make a sngle set of predictions - for example of global temperature. People who question models often talk as if they do, but in fact these models actually make many different predictions about the atmospheric and climate. Each of these can be compared to observation. the number of different sorts of predictions actually provides a fairly stringent test of the models
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Tom Curtis at 15:06 PM on 21 February 2015Models are unreliable
Sangfroid @791:
"Also, it would be very eye opening to see the source of the actual data, how it is interpreted, and what assumptions are included in their climate models. If we demand openness in government we should also demand it on something as importand as this."
The assumption here is that the data is not available to the public. That assumption is false. For all climate models, the basic assumptions and fundamental equations are specified in the peer reviewed literature, as for example the GISS Model E. Updates will also result in detailing in the peer reviewed literature, either in seperate papers for major updates, or as part of the paper in which the update is first used for minor updates. Further, for some models (notably the GISS Model E) full code is available for earlier versions, and considerable effort is made to make the code available to the public in a convenient format, as detailed here. Nor is NASA alone in granting this level of access to the code. Indeed, one climate model (CCSM 3.0) was explicitly designed to be available to the public, and is freely downloadable along with all relevant documentation.
So, the problem is not the availability of code and assumptions for analysis. It is that so called "skeptics" do not make use of resources made available to them to run their own climate experiments, or to modify the models according to the principles they think will hold. I presume that is because they are quite aware that the result, if they did, would be a very much poorer fit with the data than is provided by the standard models.
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Tom Curtis at 14:37 PM on 21 February 2015Models are unreliable
Sangfroid @791, there is a major difference between the stockmarket (or currency trading) models and climate models. That is, the stockmarket models are entirely statistical. In contrast, the climate models encode well established physical laws into mathematical representations of the atmosphere. These are laws such as consevation of energy, conservation of energy, radiative transfer physics, boyles law etc. Because we cannot represent the atmosphere molecule by molecule, (or indeed, kilometer by kilometer), some of the laws are approximated based on empirical estimates of the effect of the laws in the real atmosphere. Consequently, when these models retrodict the temperature series, without having been trained on that temperature series, that is a significant prediction.
The achievement is even more impressive in that the models do not predict just a single time series (again unlike stock market models). The predict temperature series for a variety of different altitude and depths of the ocean. The predict major atmospheric and ocean circulations (including ENSO like effects). The predict precipitation changes, and changes in sea and land ice. They are not perfect at any of these - indeed do not always agree among themselves at any of these - but they do so with very far above chance accuracy. This would not be possible if they did not get the fundamental processes right - and if they were not in the right ball park for the subtle effects.
So, quite frankly, I consider your analogy to be on a par with somebody insisting that because a particular sum cannot be calculated in a reasonable time on an abacus, it cannot be calculated in much better time on a Cray xc-40.
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Rob Honeycutt at 14:29 PM on 21 February 2015Models are unreliable
Sangfroid... There's a huge difference between financial models and climate models. Climate models are based on physical processes. Financial models are subject to varying human behavior. Gavin Schmidt has a great TED Talk about climate models that you should listen to.
"Weather [...] is totally random."
If weather were totally random then you'd get snow in the summer and sweltering heat waves in the winter. Your statement is patently absurd.
With regards to the rest of your comment, all the information is there. You just have to dig in and start reading. Understand that the body of scientific research is produced by researchers who've dedicated their lives and careers to getting this stuff as accurate as possible.
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Sangfroid at 14:17 PM on 21 February 2015Models are unreliable
When I had taken on the task of learning to trade stocks and currency a few years ago, I was amazed at the number of 'models' that were 'back tested' to be accurate. They tended to be somewhat accurate - until they failed.
Most scientists do not understand randomness and the role it plays in all aspects of our lives. We exist totally due to randomness. Weather - despite how much we think we understand the interactions of everything that affects weather - is totally random. We will never be able to predict, with certainty, the future of weather.
Many, if not all, of the so called solutions to curb CO2 emmisions, or to curb sunlight, or to convert to alternate energy sources, - although they may be necessary - do not address the effects on many people in the middle income brackets and below. Some do not address the potential negative effect on our health.
I would like to see the data that scientists use to predict the negative effects on our environment, animals and humans. Polar bears are often used as an example. Polar bears can survive without the ice covered artic as they do in parts of eastern Canada.
Also, it would be very eye opening to see the source of the actual data, how it is interpreted, and what assumptions are included in their climate models. If we demand openness in government we should also demand it on something as importand as this.
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michael sweet at 11:17 AM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Drebich,
When you start your post off with "Please don't think that I am trying to be facetious in anyway" and then say "any higher, Man Made Global Warming, any lower,.....well....Man Made Global Warming" you come across as facetious, rude and disrespectfull. Perhaps you need to check your posts before you post them. If you cannot abide by your own post why don't you just go away?
Moderator Response:[PS] Would anyone else tempted to comment here please note the "no dogpiling" rule in the comments policy. I think Drebich has been given enough to think about already and will hopefully use the resources to become better informed.
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Rob Honeycutt at 10:22 AM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
drebich... No offense intended here, but each of your questions is about what "should" each of these aspects of the climate system be. That's an irrelevant question. The problem is related to the rate of change that is being caused by human CO2 emissions and how those change will impact natural and human systems.
But, please do take the time to read through the relevant materials to fully inform yourself before coming to a firm conclusion one way or another. The science is there, it's very well established, and scientists have a very high degree of certainty that continuing on the emissions path we're on through the 21st century would bring with it severe consequences.
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Tom Curtis at 10:17 AM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
drebich @19, your questions are nonsensical.
Taking the first question, sea levels change regionally due to changes in wind circulation and ocean heat content. On top of that, there are tides, waves, and storm surges, all of which contribute to a very variable local sea level. Finally, different shores are rising, or falling due to plate tectonics, and in some locations, due to an ongoing rebound from the melting of the massive ice sheets of the last glacial. Consequently, while taking an average of a globally distrubuted collection of tide gauge measurements can unequivocally show that sea levels have rising at a rate inconsistent with the planet not warming (see graph below), no mark on a beach can plausibly be a demarcation point, unless set high enough that it will not be passed for several decades.
Your second question makes even less sense in that you want a demarcation point between ice age and global warming from sea ice. That is a nonsense request as, first, the cause if ice ages is the spread of ice sheets on land, rather than the sea ice itself; and second because we have just come of 10,000 years of interglacial (colloquially, not an ice age) which was not a period of global warming, let alone anthropogenic global warming. While the history of sea ice in the NH unequivocally shows the current dearth of sea ice to be astonishing (absent global warming) and unprecedented in recent times (see graph below), there is no limit such as you illogically ask for.
Your third question, unfortunately shows that your post is an entirely rhetorical excercise. That is unfortunate because, allowing for a small middle range, it is the most easilly answered. The fact is that Global Mean Surface Temperature (GMST) has not recently varied greatly with time. Over the last 10, thousand years, the temperature range has been about 1 C, yet we in the last century have seen the temperature rise from near the lowest value in that period to probably the highest:
Again, this rate of temperature increase is unprecedented over the last 10,000 years and probably over the history of the Earth. Further, that temperature keeps on rising, with new records for GMST having been set in 1973, 1980, 1981, 1987, 1988, 1990, 1995, 1997, 1998, 2005, 2010, and now 2014 (GISS LOTI, other indices will vary slightly), ie, on average once every four years over the last forty odd years. (In contrast, the last cold record GMST was in 1909.) If that average rate of new records is maintained, then we have global warming. If temperatures fall below the 1970s average without major volcanism, a nuclear war or a massive asteroid bombardment, then global warming has stopped. The evidence currently certainly indicates continuing global warming.
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Rob Honeycutt at 10:14 AM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
I just noticed that link to the biggest control knob video is old. You need to go here now to view that video.
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drebich at 09:28 AM on 21 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
I am obviously not a scientist. I am just an average working person, but I do have a few questions. Please don't think that I am trying to be facetious in anyway, but I cannot help the fact that "Man Made" Climate Change Scientists come across (to me) as being quite intellectually arrogant (perhaps for good reason). So, based on the fact that we all are standing on thin, broken slabs of earth floating on a massive ball of molten rock, here are my questions:
- Sea levels are rising-Which Scientist is willing to take me down to the beach, draw a line in the sand and say "That is where sea level should be, any higher sea level is rising, any lower, sea level is receding.
- The Polar Caps are melting-Which Scientist is willing to declare how many square miles of ice caps the earth is supposed to have, any more, Ice age, any less, Man Made Global Warming.
- Man Made Global Warming-Which Scientist is willing to commit to a fixed average temperature of the earth and declare that that is what the temperature has to be, any higher, Man Made Global Warming, any lower,.....well....Man Made Global Warming.
Again, I am not trying to be rude or disrespectfull in any way, these are just questions an average person would like to have a scientist responde to. I see alot of data and numbers in the comments on here. Alot of talk about trends, averages, and percentages. But it all seems irrelavent in relation to this huge planet, with all its tremendous power, and with all the monumental changes over billions of years. Continents moving and colliding, ice ages, seas of boiling sulfer. I mean, it just comes across as almost unintelligent to think that man could possibly have any influence at all. I do believe in Climate Change because, well...., the climate changes and has been for longer than 200 years. And I didn't even need to be a scientist to know that.
Regards,
Daniel
Moderator Response:[RH] Welcome to Skeptical Science! There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions. That's why we recommend that Newcomers, Start Here and then learn The Big Picture.
I also recommend watching this video on why CO2 is the biggest climate control knob in Earth's history.
Further general questions can usually be be answered by first using the Search function in the upper left of every Skeptical Science page to see if there is already a post on it (odds are, there is). If you still have questions, use the Search function located in the upper left of every page here at Skeptical Science and post your question on the most pertinent thread.
Remember to frame your questions in compliance with the Comments Policy and lastly, to use the Preview function below the comment box to ensure that any html tags you're using work properly.
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Tom Curtis at 09:10 AM on 21 February 2015Tom Harris' Carleton University Climate Misinformation Class
It turns out that Scholar's and Rogues has an excellent series dissecting Tom Harris's prevarications and hypocrissies. So far we have:
Tom Harris – hypocritical peddler of deceitful climate change editorials
Tom Harris’ recent commentaries rife with errors and illogic
Tom Harris places absurd limits on scientific truths and elevates ignorance to equal knowledge
Tom Harris’ commentaries intended to impede, not advance, public understanding of climate science
The series has one more post to go, and is written by Brian Angliss. Tom Harris makes an appearence on comments.
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wili at 07:33 AM on 21 February 2015A melting Arctic and weird weather: the plot thickens
Another good discussion of these interconnections at robertscribbler: Mangled Jet Stream + Global Warming + Hot Atlantic Water = Boston Buried Under 8 Feet of Snow
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hank at 07:15 AM on 21 February 2015A melting Arctic and weird weather: the plot thickens
Living in California, I know the area has paleo (lake sediment) proxies showing extreme prolonged dry spells; one academic page has cites:
http://blog.lib.umn.edu/stgeorge/geog5426/2010/11/summary-of-megadrought-ii.html —
quoting from one:
"Laird PNAS 2003 paper is a story about large-scale moisture shifts across the northern prairies of North America during the past 2000 years. Authors using 6 lake sediments across the North American prairies show that two different types of major shifts in moisture regimes (from wet to dry or from dry to wet) existed for at least the last two millennia.... Such large-scale moisture shifts were thought to be caused by the expansion of the polar vortex, and may be a common phenomenon which may reoccur over longer time frames. The differences in timing of moisture shifts were explained as the fluctuations in the position and shape of the jet stream."
(They don't say _why_ the jet stream varied in the past, and I'm assuming you'd have to look through a lot of proxies over a large area to guess)
Is there enough data on year to year variability over the long term past to say what's happening now is within that "noise" or is a detectable climate signal emerging from the noise?
Moderator Response:[JH] Link activated.
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danielbacon at 05:15 AM on 21 February 2015A melting Arctic and weird weather: the plot thickens
With the last SSW around the first of this January.
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danielbacon at 05:08 AM on 21 February 2015A melting Arctic and weird weather: the plot thickens
In your research do you exclude the effects of Planetary-scale wave activity for stratospheric sudden warming events (SSW) that weaken the stratospheric Vortex (SVW)? It would seem that the primary driver for (troposphere) Northern Hemisphere Wintertime Weather is the propagation of the Arctic Oscillation from the stratosphere by SSW and SVW or I am confusing the issue in my head?
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Roger D at 00:34 AM on 20 February 2015LBJ's climate warning 50 years ago - do we have your attention yet?
Thanks for this. Great points to counter the misimpression of many contrarians that concerns over global warming are primarily based on an Inconvenient Truth, or began with the formation IPCC, ideas that the conspiracy minded really want to hold on to. That the reality of today syncs very well with the scientific understanding of half a century ago, forming a foundation for continued understanding is a powerful argument for climate science.
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alby at 19:13 PM on 19 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Sorry I wrote 0.017 instead of 0.17
...and now I see teh short answer from Kevin C.
Regarding Gleisner in Fig. 5 they found the arctic influence to global T trend, because on fig. 5 the difference from original HadCRUT4 data (yellow line) and Gleisner (black lien) starts from latitude > 70 N.
Additionally Kriging (blue line) increase the global T from 0.08 up to apporx. 0.11 but (comparing to Gleisner trend) with a visible contribution (approx. 0.02) coming from latitude < 70
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alby at 19:01 PM on 19 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
gregcharles: the articles doesn' t misreports T trends. Look at the right end (right because the graph is cumulative) of fig.5: original data from HadCRUT4 (yellow line) shows for the period 1997-2012 a trend of 0.05 °C/decade (less than 0.017) as reported in the article before fig. 1 "The trend in HadCRUT4 over that period is about 0.05°C/decade". Now, there are two facts: the artic trend alone is much higher (approx. 1.5 °C/decade) and the surface of the artic region is roughly 1/10 of the global surface with only a partial coverage from HadCRUT4. Consequently including the "missing region" of the artic in the global trend this will increase, adding 0.03 or 0.04 to 0.05 to, up to 0.08/0.09 (see black line on the right end of fig.5). The "missing region" is (quote from the article) due to "HadCRUT4 had on average 64% coverage for the region north of 60°N ... This region corresponds to about 6.7% of the planet's surface. Therefore the missing region corresponds to about 2.5% of the planet"
0.36 x 6.7% = 2,41%% or roughly 2.5%
and 1.3 °C/decade x 2.5/100 = 0,03 °C/decade (for 1.7 the contribution is 0.4).
I hope (if I'm right, if not someone will correct) to have been clear.
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Kevin C at 18:37 PM on 19 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
No, the trends N of 70N really are around ten times higher than the long term trends for the planet as a whole. That is how 2.5% of the planet can influence the global trend. That may seem incredible, but it is confirmed by us, Berkeley, all of the reanalyses and AVHRR. GISTEMP capture most of it, albeit with poorer coverage and some other problems.
And actually so does the Gleisner reconstruction, despite the fact that they say they can't find it - that was a bit strange.
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gregcharles at 13:10 PM on 19 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Thanks to Firgoose for working out those links. I was also scratching my head after first clicking on the Check It Yourself links.
Another head-scratcher for me: does it seem like this article consistently misreports temperature trends by a factor of 10? For example, "The rate of Arctic warming in the MERRA for region north of 70°N, where most of the missing coverage occurs, is 1.3°C/decade. The ERA-interim reanalysis shows a higher rate of 1.7°C/decade." Global warming trends are about 0.17°C/decade, right? Maybe, I'm misunderstanding what's being reported here.
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jja at 11:13 AM on 19 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Kevin, thank you for your reply, sorry for the late response. The DMI data that I was referencing is the "north of 80N" series found here:
http://ocean.dmi.dk/arctic/meant80n.uk.php -
Tom Dayton at 02:59 AM on 19 February 2015We're heading into an ice age
Climate Dialogue has a good and recent overview of the potential effect of a new Maunder Minimum, in its "Introduction" to that topic.
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Tom Dayton at 02:57 AM on 19 February 2015It's the sun
Climate Dialogue has a good and recent overview of the Sun's potential role in Earth's temperature increase--not just with regard to the effect of a new Maunder Minimum--in its "Introduction" to its New Maunder Minimum topic.
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ranyl at 20:17 PM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Thanks Kevin.
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One Planet Only Forever at 13:36 PM on 18 February 2015Scott Mandia on teaching students to debunk climate misinformation
You should consider ensuring you use the terms 'skeptic' and 'climate denier' accurately in your presentations.
The New York Times recently presented this article "Verbal Warming: Labels in the Climate Debate". (this is also one of the articles in the 2015 SkS Weekly News Roundup #7B)
The article is about a US scientist, Mark B. Boslough, who objects to calling people who create unjustified attempts to discredit climate science 'skeptics'. His open leter on the matter has spawned a petition to have the media refer to such people as 'climate deniers' rather than 'skeptics'.
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jja at 09:56 AM on 18 February 2015NASA climate study warns of unprecedented North American drought
Ben Cook's intimation that the current california drought is a natural cycle event is overstated. His work can only assert this is natural because the regional sea surface temperature anomalies do not show up in the climate models and there is no downward precipitation treand that is statistically significant from the highly variable history data.
It is very likely that the models are simply not adequately addressing regional anthropogenic aerosol patterns, the effects of Hadley expansion in mid-latitudes, the combination with this and arctic amplification effects on the jet stream, shifts in the inter-tropical convergenze zone due to north vs. south hemisphere aerosol loading and (possibly) the effects of deforestation in the south american tropics See: http://www.accuweather.com/en/weather-news/amazon-climate-change/20184965"All of this has to do with a tipping point," Symington said. "With deforestation, if you go beyond a certain point in the Amazon there's an issue of where the whole system becomes destabilized and you would switch from a tropical, moist forest system, to something that was much drier and more like the Cerrado of central Brazil, sort of a dry forest, savanna system. If that happened it would have a huge impact on species in the Amazon and also on the climate."
About 20 percent of the fresh river water in the world comes from the Amazon River, and drying of the forest can negatively influence that water source. Symington told Accuweather.com that changes to this freshwater output would affect the entire current off the coast of South America, which could affect the jet stream, which would ripple into a change in weather patterns across the globe.
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Tom Curtis at 07:30 AM on 18 February 2015NASA climate study warns of unprecedented North American drought
Firgoose @6, BAU may be limping, as you say, but that does not mean the course we follow will be towards less CO2 emissions. It is very possible that a dirth of sources of liquid fuels will result in replacement by fuels that emit far more CO2 over the entire production process, per liter of fuel used on the road. That would switch us to a BAU+ path rather than the BAU- path we are currently limping along.
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Kevin C at 05:31 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
If there's a way to get the trend in KNMI, I haven't found it either. Click 'raw data' above the third graph and copy it into a spreadsheet. The lack of 700mb trend you can see by eye though.
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Firgoose at 05:25 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
For those, like me, who clicked the "Check it yourself" links and came back with a well-scratched head, wondering why both links go to the same place, and what to do with this amazingly complicated looking, scrollfest of an interface anyway? ... the instructions are in a tooltip that shows if you hesitate over "Check it yourself" for long enough before clicking; a fortunate but accidental discovery in my case. ;-) Reading tooltips while clicking widgets on a different page is for magicians so here are the instructions ...
For the ERA-interim reanalysis rate of Arctic warming in the region north of 70°N : Select ERA or MERRA (show/hide) — click temperature/2m (radiobutton) — click "Select Field" (button) — fill in latitudes 70N-90N — optionally click "convert to Celsius" (radiobutton) — click "Make time series" (button).
If I did it correctly, this should be a direct link for ERA.
And for MERRA
For the trend "3km into the atmosphere to the 700mb level" it's almost identical to the above : Select ERA (show/hide) — click temperature/700mb (radiobutton) — click "Select Field" (button) — fill in latitudes 70N-90N — optionally click "convert to Celsius" (radiobutton) — click "Make time series" (button).
However, if the results are supposed to draw the trend or and give a value, I've no idea what I missed. :-/
Moderator Response:[RH] Shortened links that were breaking page format.
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Kevin C at 05:07 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Ribwoods: Fixed, thanks. (Figure 1 was a late addition)
jja: The Arctic report card doesn't go into the methodology in detail, but an average to 60N will be dominated by the stations in the 60-70N band. ERA-i, JRA, Berkeley Earth and ourselves all show less extreme temperatures on the region N of 70N in 2013.
wili: That's something we're hoping to look into, but haven't had a chance to yet.
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wili at 04:37 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Thanks for the response, Kevin. "We've seen examples of rapid Arctic warming like this in models, but is is never longlived. That suggests we shouldn't expect the trend to continue"
So, do we have any idea what drives periods of greater rather less rapid Arctic warming? If we don't, how can we know that this is really something cyclical, especially with all the added forcings and feedbacks of our ever wierder global wierding?
By the way, I see that temperatures north of Norway now reach into the 40s F (5.5 C). earth.nullschool.
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ribwoods at 03:43 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
And in the second paragraaph after Fig. 5, the fourth sentence starts "The results are shown by the black points in figure 4 ...:, but s/b "... in figure 5 ..."
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ribwoods at 03:35 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
In the article, the paragraph just prior to Fig. 3 starts "The errors in the different reconstructions by month are shown in figure 2", but should be "... in figure 3."
The paragraph just prior to Fig. 4 starts "If we include all three temperature reconstructions in the latitudinal temperature plot, we obtain figure 3", but s/b "... obtain figure 4."
The second paragraph after Fig. 4 starts "One other feature is shown by the thin grey lines in figure 3", but s/b "... in figure 4."
The paragraph just before Fig. 5 ends with "This period is shown in figure 4:", but s/b "... in figure 5:"
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jja at 03:28 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Kevin,
WRT your response above, the ARC for 2014 showed that 2013 was near the record high warming (fig 1.1) http://www.arctic.noaa.gov/reportcard/air_temperature.html
and the DMI has winter 2014 as near record high as well. Please explain? -
Firgoose at 03:16 AM on 18 February 2015NASA climate study warns of unprecedented North American drought
"If we follow the business-as-usual path, ..."
Fortunately, this statement will become as redundant, tedious and irrelevant as the apparently mandatory "If all the ice in [Antarctica | Greenland] melts". All of that ice is not going to melt for a very long time and we're not going to follow business as usual. We're already not following that trajectory, as both intention and action increase at the political and corporate levels.
The writing on the wall is being read, deniers are becoming dinosaurs walking on ever soggier sands, may their bones make interesting fossils. Joe Public is becoming more sympathetic to the plight of the future even if there's still a lot of resistance to actually doing anything personally. Joe will come round, whether stampeded by Gaia saying "Boo!" or herded by the Powers That Be/Will Be.
Forsooth, we probably won't get to a "below 2°C" but "business as usual" is limping and is going to have to drop out of the race.
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Kevin C at 02:10 AM on 18 February 2015Missing Arctic warming does contribute to the hiatus, but it is only one piece in the puzzle.
Ranyl: Yes, I think you've got the gist of it. I guess you'd call it a cumulative zonal trend plot. The uptick in the last 30 degrees on the right is the Arctic contribution to the global trend. Given the tiny area concerned, you would expect it to be flat. But it isn't, even in the Gleisner reconstruction, showing that the Arctic is playing a role.
The difficulty with the non-cumulative version is that the affect of the different areas of the zones is lost, unless you choose equal area zones.Wili: We've seen examples of rapid Arctic warming like this in models, but is is never longlived. That suggests we shouldn't expect the trend to continue. And indeed the last two winters support that expectation.
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