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Comments 24851 to 24900:

24851. Tom Curtis at 13:53 PM on 31 March 2016
       Global Warming Basics: What Has Changed?
       

       billev @42:

       "The NOAA temperature charts clearly show me that while the Earth is warming, the warming is not continuous. If this is not the case then the charts are misleading so why are they provided to the public? There is a determined attempt to argue that there has been no pause in continuous warming in this century even though the chart shows there to be."

       Nobody here has argued the warming is continuous.  What has been argued is that your choice of breakpoints for long term trends are arbitrary, that there is no justification for seeing them as a repeating pattern, and that there is no breakpoint in 2002.

       What the charts show after 2002 is a continuing positive trend that is not statistically significant only due to the small duration of the period.  Further, the slope is lower than that of the trend of the preceding 30 years only because of strong La Ninas in 2008, and 2011/12.  You argue that unusual peaks should not be factored into determining trends, but insist on including those in your trend calculation while refusing to acknowledge they are the impact of a short term effect.

       What is worse, since this has been clearly pointed out to you, you have introduced no new evidence, made your claims vaguer and simply repeated the claims with no attempt of justification.  Your argument has reduced to the repetition of a slogan.

       You have similarly studiously ignored the refutation of your claim that CO2 has not effect @22 above.  Once again, the graph shows the IR spectrum at the top of the atmosphere, plotted so that equal areas under the graph represent equal amounts of total energy transmitted.  The large trough due to CO2 therefore implies a large reduction in energy transmitted to space due to CO2.  That in turn requires that the surface of the Earth be warmer to drive greater energy transmission away from the CO2 trough to compensate, and bring the total energy transmission up to levels that match input of solar energy.

       That is a very simple, very direct proof of the impact of CO2 on climate.  It is based both on direct observations, and on models based on direct laboratory observations of the radiative properties of gases.  In this instance, theory matches observations to an astonishing degree.  Your commentary on the topic since has shown that you are determined to avoid evidence you do not like.  If you are going to simply avoid evidence that challenges your views (as clearly you are) it will be much more convenient for both you and us if you do it elsewhere. 

24852. denisaf at 10:19 AM on 31 March 2016
       Six burning questions for climate science to answer post-Paris
       

       The tipping point was reached decades ago so irreversible rapid climate change and ocean acidification and warming is under way. The most mitigation that can possibly be done is to institute a number of measures to reduce the rate of emissions so slow down the rate of increase in atmospheric and ocean temperature. Suggesting that this temperature rise can be limited is erroneus. There should be more focus on measures to cope with the consequences, such as sea level rise and storm surges.

24853. Nick Palmer at 09:30 AM on 31 March 2016
       Six burning questions for climate science to answer post-Paris
       

       Regenerative agriculture holds the promise of being way more effective than biofuels with carbon sequestration
       
       https://en.wikipedia.org/wiki/Regenerative_agriculture

24854. Dcrickett at 09:01 AM on 31 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Certain CO₂ abatement policies — such as the Carbon Tax — are clearly more effective than others — such as massive regulation. I think 'most anybody prefers the Invisible Hand of Adam Smith over the Heavy Hand of a Soviet Five-Year Dictum. And regardless of the currently apparent popularity of certain US and other wuzbe Cæsars, a real turnaround in attitudes is at hand. The problem appears to be that certain people have attained unjustifiable wealth and power and are ready to use unjustifiable means to maintain their unjustifiable holds on the aforementioned unjustifiables.

       The best option is to try to change the system while change is possible. Otherwise we will hear the people singing the songs of angry men as they get out their torches, tumbrels and Remington 870’s, which will not have happy outcomes.

24855. Tom Curtis at 08:58 AM on 31 March 2016
       A methane mystery: Scientists probe unanswered questions about methane and climate change
       

       RedBaron @18:

       "In my opinion methane is a problem primarily because of CAFO's. It is not a problem in a properly managed grassland/savanna biome. After all those biomes supported many millions and millions of grazers who were extirpated. The methane levels before they were extirpated were actually lower than now!"

       You have this backwards.  The current megafaunal biomass is approximately 7 times that prior to human induced mass extinctions.  The biomass of human livestock alone is 4.5 times that of all megafaunal biomass prior to human induced mass extinctions.  See Barnosky 2008:

        

       So, quite aside from the fact that not all grazers produce methane in the quantities of cattle, the amount of cattle now far exceeds the quantity of wild grazers they have displaced.  Even the estimated 60 million American Bison pre-1800 have been replaced by 90 million cattle in the US alone, a further 12 million in Canada, (plus 500,000 Bison).

24856. RedBaron at 06:17 AM on 31 March 2016
       A methane mystery: Scientists probe unanswered questions about methane and climate change
       

       In my opinion methane is a problem primarily because of CAFO's. It is not a problem in a properly managed grassland/savanna biome. After all those biomes supported many millions and millions of grazers who were extirpated. The methane levels before they were extirpated were actually lower than now! According to the following studies those biomes actually reduce atmospheric methane due to the action of Methanotrophic microorganisms that use methane as their only source of energy and carbon. Even more carbon being pumped into the soil! Nitrogen too, as they are also free living nitrogen fixers.
       http://blogs.uoregon.edu/gregr/files/2013/07/grasslandscooling-nhslkh.pdf
       http://www.ncbi.nlm.nih.gov/pmc/articles/PMC239458/pdf/600609.pdf
       LINK
       http://www.ncbi.nlm.nih.gov/pubmed/11706799
       http://journal.frontiersin.org/article/10.3389/fmicb.2013.00225/full
       http://www.sciencedirect.com/science/article/pii/0038071794903131

       Grasslands and their soils can be considered sinks for atmospheric CO2, CH4, and water vapor, and their
       Cenozoic evolution a contribution to long-term global climatic cooling.

       The subsurface location of methanotrophs means that energy
       requirements for maintenance and growth are obtained from
       CH4 concentrations that are lower than atmospheric

       Upland (i.e., well-drained, oxic) soils
       are a net sink for atmospheric methane; as methane diffuses from the atmosphere into
       these soils, methane consuming (i.e., methanotrophic) bacteria oxidize it

       Nevertheless, no CH4 was released when soil surface CH4 fluxes were measured simultaneously. The results thus demonstrate the high CH4 oxidation potential of the thin aerobic topsoil horizon in a non-aquatic ecosystem.

       Of all the CH4 sources and sinks, the biotic sink strength is the most responsive to variation in human activities

       The CH4 uptake rate was only 20% of that in the woodland in an adjacent area that had been uncultivated for the same period but kept as rough grassland by the annual removal of trees and shrubs and, since 1960, grazed during the summer by sheep. It is suggested that the continuous input of urea through animal excreta was mainly responsible for this difference. Another undisturbed woodland area with an acidic soil reaction (pH 4.1) did not oxidize any CH4.

       Moderator Response:

       [RH] Shortened link that was breaking page format.

24857. KR at 05:51 AM on 31 March 2016
       Global Warming Basics: What Has Changed?
       

       billev - Your last comment is really just a Gish Gallop, a collection of slogans, anecdotes, and nonsense. I suggest reading:

       • How do we know more CO2 is causing warming (empirical evidence)
       • Explaining how the water vapor greenhouse effect works, also Richard Alley on the CO2 'Control Knob'
       • CO2 is not the only driver of climate (why warming isn't monotonic wrt CO2)
       • On Statistical Significance and Confidence (why we're certain that AGW hasn't stopped, despite short term variations)
       • Argument from incredulity fallacy (disbelieving the effect of increased CO2 because of the ratio to non-IR active gases)
       • Greenhouse effect basics (why your hot feet are really irrelevant to what's going on at the top of the atmosphere)

       Seriously, your post is nothing but a bag of sloganeering nonsense, the errors of which has already largely been pointed out to you. 

24858. MA Rodger at 02:28 AM on 31 March 2016
       Global Warming Basics: What Has Changed?
       

       billev @42.

       I will take just one of the questions you pose and provide an answer, in exchange for an answer from you.

       If we stand on the hot sand of a beach the bottoms of our feet are most uncomfortable but the tops of our feet, only an inch from the sand, are not. If the heat retention power of CO2 is enough to drive the air temperature on Earth why does it appear so ineffectual at preventing such significant heat loss so close to the source.

       When you stand on that hot sand, the reason the blood above the soles of your feet does not freeze in your veins is because there is an insulating atmosphere above you preventing the low temperatures of outer space from sucking the heat from your body. That atmosphere above you stretches eight miles up to the stratosphere and up beyond that as well. Over that eight miles the temperature drops about 70ºC, less that 10ºC per mile, a rate of temperature reduction not noticable over a few feet. It is the accumulative effect over the whole height of the atmosphere that does the job. So most of that insulating air is well over a mile away. At such a distance, why would it reflect back the heat from hot sand and toast the top of your foot at the same time as the bottom? Simply, it would not because it is almost entirely far too far away for to catch anything significant of the heat emitted by the sand and return it to the top of your foot.

       And my question to you - You say "I have previously stated that the presence of a current pause in temperature rise will probably be more evident in another ten or fifteen years, toward the end of the pause." We know day follows night, winter follows summer and that they recur at fixed intervals. What mechanism is it that makes you think that your "pauses" recur at a fixed interval?

24859. billev at 00:48 AM on 31 March 2016
       Global Warming Basics: What Has Changed?
       

       I have read the thread about CO2 and have read all of the comments in answer to my last comment.  Nowhere have I found any measure of how effectively CO2 captures and retains the heat radiating from the surface of the Earth and solid objects on its surface.  I do know that the difference between daytime and night temperatures is significantly different in arrid areas than more humid areas indicating that water vapor may play a role in heat retention in the hours of darkness.  The NOAA temperature charts clearly show me that while the Earth is warming, the warming is not continuous.  If this is not the case then the charts are misleading so why are they provided to the public?  There is a determined attempt to argue that there has been no pause in continuous warming in this century even though the chart shows there to be.   I have previously stated that the presence of a current pause in temperature rise will probably be more evident in another ten or fifteen years, toward the end of the pause.  Also, comparing a small amount of arsenic with a small amount of CO2 is meaningless.  It also is an argument that can be taken two ways.  A one inch thick steel sheet can, no doubt, stop a pistol bullet fired into it.  But a sheet of steel 1/2500th of an inch thick would probably not even slow the bullet as it passed through.  Finally, where is there any physical manifestation in our daily life that shows the heat retention powers of CO2.  If we stand on the hot sand of a beach the bottoms of our feet are most uncomfortable but the tops of our feet, only an inch from the sand, are not. If the heat retention power of CO2 is  enough to drive the air temperature on Earth why  does it appear so ineffectual at preventing such significant heat loss so close to the source.  Since that heat loss increases as distance from the surface increases is there any evidence that the current level of CO2 has any measureable effect on temperature?  

       Moderator Response:

       [JH] You are now skating on the thin ice of sloganeering which is prohibited by the SkS Comments Policy. 

       Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

       Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

24860. h4x354x0r at 00:25 AM on 31 March 2016
       CO2 measurements are suspect
       

       Thank you for the explanation, Tom Curtis. I had to get into my wayback machine and go visit my high school physics class, but the pointer towards Henry's Law helped break my metal logam, there. The annual variability is between 6-7 PPM; the annual increase is now a solid 3 PPM, and of course growing. It would be nice not to find out what will happen when the annual increase overtakes annual variability. 
       
       Again, thank you! 

24861. Tom Curtis at 22:56 PM on 30 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       A comment by Trevor_S elsewhere has shown me I was too optimistic in my point 3 @12 above.  In particular, he shows a graph from Fuss et al (2014) that shows CO2 emissions as of a 2014 estimate to be tracking RCP 8.5.  Checking more recent data including LUC, I see that the comparison of level of emissions between current levels and RCP 2.6 above was (unintentionally) misleading.  We are in fact doing better than RCP 8.5 in that we are plateauing emissions, but from RCP 8.5 equivalent levels, not from RCP 2.6 levels.

       While this slightly reduces my optimism, it does not alter the appropriate strategy; or considerations in favour of it.

24862. Tom Curtis at 22:45 PM on 30 March 2016
       Heat from the Earth’s interior does not control climate
       

       If the moderators will allow it I would like to note for the benefit of pjcarson:

       1)  "sloganeering" is implicitly defined in the updated comments policy, which states:

       "No sloganeering. Comments consisting of simple assertion of a myth already debunked by one of the main articles, and which contain no relevant counter argument or evidence from the peer reviewed literature constitutes trolling rather than genuine discussion. As such they will be deleted. If you think our debunking of one of those myths is in error, you are welcome to discuss that on the relevant thread, provided you give substantial reasons for believing the debunking is in error. It is asked that you do not clutter up threads by responding to comments that consist just of slogans."

       I have added emphasis to indicate the key sentence which defines "sloganeering" (underlined), and the key feature of sloganeering that makes it mere noise in any attempt at reasonable discussion (bolded).

       In registering with SkS, you agreed to abide by the comments policy when posting, and therefore should have read it.

       2)  By the same token, moderation complaints are also forbidden in the comments policy (the reason your most recent post was deleted).

       3)  For what it is worth, I am not a moderator; but was when the updated comments policy was introduced. 

       4)  If you were to post the substance of your most recent post with actual peer reviewed numbers regarding "the change of heat due to tectonics", it would probably get past the moderators (unless you do something silly like all capitals, etc).  Absent actual peer reviewed numbers, a quick look at your site shows your own calculations to be worthless - something easilly discovered to be the case with regards to your comments on the greenhouse effect in substantially less than eight minutes.  If you want to criticize a scientific theory, it is essential that you actually understand it first, which clearly you do not.  If you want to learn, here is a good starting point.

24863. Tom Curtis at 22:30 PM on 30 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       denisaf @9, by a similar verbal contortion we can say that (in the majority of cases of violent death) people do not kill people, rather guns kill people.  However, a murderer running that argument in support of a plea of not guilty would get short shrift indeed.  That is because people understand perfectly well the concept of indirect agency, and hence you have no point.

24864. Tom Curtis at 22:26 PM on 30 March 2016
       Six burning questions for climate science to answer post-Paris
       

       TomR @2, do a google search for biochar.

24865. TomR at 22:20 PM on 30 March 2016
       Six burning questions for climate science to answer post-Paris
       

       Burning biofuels for energy would hurt food production as it already is with corn ethanol, and soy and palm oil diesel. It would also add to emissions as is occurring with UK chopping down American forests to feed the huge Drax power plant with wood pellets. With wind and solar, we really don't need biofuels which also add to air pollution since only about half of the CO2 is captured.

       It seems to me that simply burying dead wood and plants in manmade lakes would imitate nature, i.e., how coal and peat deposits were created. It would also appear lower cost per ton of carbon captured. Such deposits would seem much more stable than pumping gas into the earth. I haven't heard anyone explore this idea, although I have read of its reverse, i.e., logging century old forests under the waters of dammed up rivers.

24866. denisaf at 20:37 PM on 30 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       Misleading terminilogy doea not help in convincing what is happening. People are not causing cliamt change. It is the operation of technical systems that is producing the emissions doing the damage. people only make decisions, good and bad, about the use of technical systems.

24867. radioAlex at 11:16 AM on 30 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Listen to my Radio Ecoshock interview with Ben Hankamer here:

       http://tinyurl.com/jguk7gy

24868. Trevor_S at 09:40 AM on 30 March 2016
       Six burning questions for climate science to answer post-Paris
       

       >We will not meet the targets if the world relaxes on mitigation efforts

       wait...what ? We're bang on track for RCP8.4,

       

       we've not mitigated at all, 2015 was a record year for CO2 emisisons and CH4 emisions have increased significantly over the last decade or so.

24869. barry1487 at 09:35 AM on 30 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       BBHY, there is a list of record-breaking hot/cold days per city/state since 2002 on the web.

       http://www.mherrera.org/temp.htm

24870. barry1487 at 09:31 AM on 30 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       bozza,

       https://www.jeffreydonenfeld.com/blog/2013/01/is-it-really-snowing-at-the-south-pole/

       That's something I found after 5 seconds. No doubt you could find more technical stuff with little effort. Google is your friend.

24871. Hank11198 at 08:43 AM on 30 March 2016
       Models are unreliable
       

       Does anyone know where I can find a graph that shows how the climate models correlate with temperature back to around 1880? Can't find that by using google for some reason. 

24872. John Hartz at 08:37 AM on 30 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Here's another way our current economic system should be changed... 

       A new relationship with our goods and materials would save resources and energy and create local jobs, explains Walter R. Stahel.

       The circular economy by Walter R. Stahel, Nature, Mar 23, 2016

24873. nigelj at 08:16 AM on 30 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Tom Curtis

       Thanks for your response, and yes it does explain things a lot better. I subsribe to basically the same views on politics, markets and economics in general. You might find the book "Freefall" by Jospeph Stiglitz relevant, if you have not already read it. The book is about economics and the financial crash, but he also includes some specific discussion on climate change and market regulation.

       I also 100% agree we cant wait to reform the world economy into something ideal before acting on climate change. However I'm sure Naomi Klein would also agree with this. Many things simply need to be done in parallel.

       Agree also with your third world comments. It's a tough one, but I had reached the same conclusions myself.

24874. bozzza at 04:59 AM on 30 March 2016
       How to inoculate people against Donald Trump's fact bending claims
       

       Fossil Fuel prices aren't tanking for any logical reason: some say it's to stop America drilling for their own reserves and thus it's Geo-political rather than for any natural limiting factor!

24875. bozzza at 04:31 AM on 30 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       Also, @ 4, did you know you can dry your par boiled chips in the freezer before their second deep fry?

       NB: I might not be exactly right..!(??)

24876. bozzza at 04:18 AM on 30 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       @4, I don't want to ask in the wrong forum but can you tell me: does it not snow at the poles?

        I was told it doesn't snow at the poles for the reasons you gave in the previous answer but was wondering how far away from the poles(if at all true) this takes place and how it changes,... or indeed if it is a useful indicator of climate change while we're on the subject?????????

24877. MA Rodger at 21:57 PM on 29 March 2016
       CO2 is just a trace gas
       

       Am I suffering from DPD (decimal point shift) or are we all missing a trick with this 'CO2 is just a trace gas' myth-busting? Are we missing an argument with a wow-factor-par-excellence?

       I have just been reading a screed on vaccuum, how in the most empty bits of distant space the atoms (or more correctly the bits of atoms that exist in the WHIM) are about half a metre apart. The screed contrasted this separation with the comment that out atmosphere has atoms spaced at about one million per millimetre which is getting down to the sort of distance similar to the diameter of atoms.

       So here we go:-

       There is 400ppm CO2 in the atmopshere and it requires 2.13Gt(C) to add a further 1ppm. So there is 852 Gt(C) = 8.52+e17 g(C) contained within atmposheric CO2.

       If this is divided by weight (C=12) and multiplied by Avogardo's number, we obtain a number for the molecules of CO2 within the atmosphere. 8.52e+17 x 6.022e+23 /12 = 4.28e+40 molecules CO2.

       An atom has a rough diameter of 0.3nm. Thus it has an area roughly equal to 7e-20m^2 and a sheet of carbon made from the carbon content of atmospheric CO2 would have an area of something like 6e+19m^2.

       As the area of the Earth is 510 sq km = 5.1e+14m^2, this means any point object attempting to exit the planet Earth from ground level (straight up in a straight line would be the shortest route) will have to pass through the middle of (6e+19/5e+14=) 120,000 molecules of CO2, even if they were aligned edge on and only showing an area equal to one of its atoms.

       So it appears correct to say that, while there is only a small % of CO2 in the atmosphere, the (lower) atmosphere is quite well packed with molecules and molecules are very small. So there is a very large number of molecules in the atmosohere and, even if they are only a small % of the atmosphere, there is still a very large number of CO2 molecules within the volume of the atmosphere.

       For a photon to travel the 7 miles or so to reach the stratosphere, it will pass through a very large number of atoms and a lot of them will be the atoms of CO2 molecules. To make such a journey a photon would have to negotiate its way through the middle of something like 120,000 CO2 molecules. If the wavelength of that photon is the sort that has a problem passing through CO2, any one of those 120,000 CO2 molecules could be the one that grabs it and brings its outward journey to a halt.

24878. BBHY at 21:44 PM on 29 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       Has anyone else noticed that everytime it snows some people claim that we are having record cold temperatures?

       Most meteoroligists are smart enough to know that snow and cold temperatures are two separate things. In fact, very cold temperatures generally bring little snow, as colder air can't carry much moisture.

       Meteoroligists can't help but notice that they get to say the words "record high temperatures" much more often than "record low temperatures". If nothing else that should give them a pretty good idea of what's going on.

24879. mercpl at 19:24 PM on 29 March 2016
       How to inoculate people against Donald Trump's fact bending claims
       

       There are no good choices for US president.  Even Clinton represents BAU which will guarantee catastrophee.  Obama was a good president, but proved to be totally ineffectual re climate change.

       
       The election result doesn't really matter because the US president is much less powerful than people imagine.  The real power lies with Wall street and the mega-corporations.  They are finally seeing the light as fossil fuel prices tank and their profits shrink.  As always, just follow the money.  When renewables become more profitable than fossil fuels, then we will see some change.

24880. bozzza at 18:13 PM on 29 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       @8, Nice first paragraph.

       Economies are meant to be robust and pulling out of long picked winners wasn't meant to be easy.

24881. One Planet Only Forever at 14:47 PM on 29 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Tom,
       I apologize if my persistent attempts to clarify your position (and mine) appear to be misrepresentation of your position. Let me try again.

       International Policy is only words if effective means of enforcement do not exist (that would be effective methods of dismissing sovereignty when required, something you called totalitarian which was a rather gross misrepresentation of my position, but I did not choose to claim it was).

       What Paris produced is better than without Paris, but it is still only words that can be chosen to be ignored by the current or future leadership of sovereign nations. And the US is already falling behind on the Paris pledge because the Supreme Court made an unprecedented move that barred the lower courts from proceeding with implementing enforcement of existing rules that would reduce coal burning until an appeal to the Supreme Court is heard (and the people currently hiding behind the Republican Party brand are demanding that the replacement for Justice Scalia, one of the voters in favour of the 5-to-4 split decision that implemented that unprecedented action, only be proposed after the next election, because they hope they can win the Presidency and get their preferred deciding vote into the Supreme Court, or at least benefit a little longer by delaying the advancement of humanity).

       And the apparent stranglehold on the House (the body that ultimately controls the money in the US Government), by a group of people Obama mistakenly believed could be negotiated with bodes poorly for any of the words of Paris to meaningfully change things. That group has deliberately underfunded, or made as ineffective as they could, any enforcement of the current rules of the game in America. It is very likely that a continuation of obstruction by that group like the past 30 years is to be expected (and it is not just that group in the US but also the likes of them behind similar Parties in places like England, Australia and Canada who claim to be Conservative. I know the Conservative Party lost the last Canadian election, but they are not guaranteed to lose the next one, just as the Democrats in the US are not guaranteed to win the Presidency or control of the Senate in the upcoming election, the control of the House by the Republicans is almost guaranteed).

       So your vision of effective International Policy meaningfully limiting the harm that is done by 'people who have little interest in advancing humanity to a lasting better future for all when doing so would be contrary to their personal interests in their lifetime' is only an illusion unless there is the type of international effective enforcement you declare is unacceptable.

       So my answer to your question is that there is unlikely to be any meaningful progress until there is a meaningful change of the game that dramatically reduces the ability of such people to succeed. You may want to believe that 3 degrees faced by 'future generations' is OK. But I would ask you to prove that the 3 degrees will not become 5 degrees, because the resistance to giving up undeserved opportunity for personal benefit just to reduce the troubles others will face is still able to succeed into the future.

       And I return a question about your timelime. How is your timeline affected if the current cast of Republicans continue to control the House and Senate after the upcoming election? And what if the Republicans also win the Presidency? And worst of all, what if the Republican President is Ted Cruz (a known deliberate misrepresenter of information hoping to win more success for those who do not care about advancing humanity)? If you would claim such events would have little effect on your timeline then there really is nothing more to discuss, no other way for me to understand your position.

       But I would have to add another question. Why is it OK for a portion of a current generation of humanity to continue to enjoy things that are understood to be unacceptable 'just because they had developed a burning desire and the power to get away with it'? (Sadly, the quote I shared from the 1987 UN Commission Report in my comment @13 continues to explain things very well).

24882. Tom Curtis at 12:11 PM on 29 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       nigelj @19, FWIW, although I disagree on specific policy positions based on my own analysis, my political sentiment is broadly the same as that found in the Green Left Weekly that my cousin helped found.  More specifically, I am what I call a democratic, market socialist.  

       Democratic because it is the only political system compatible the moral principle that you should always only act as though people were ends in themselves, and never merely means to an end, which I consider fundamental to ethics.   On that basis I consider the US very imperfectly democratic, primarilly due to the undue influence from campaign funding, but also due to some peculiarities of the constitution.  On the same basis I would strongly support reforming the General Assembly so that each nation had a number of its seats proportional to the population to which it gives the vote (such that, for example, if they deny votes to women, they halve their number of seats), and were the representatives are directly elected, along with other democratizing reforms for the Security Council.

       Socialist because I believe radical title to all property rests with the people, and more formally with the government acting on the peoples behalf; and that the rights accruing from that radical title (including the right to regulate and tax) should be excercized on behalf of the people generally rather than on behalf of special interest groups.

       Market because I accept that to the most part, a free market is the most efficient distributor of goods where 'free market' is implicitly defined by the fundamental argument to that effect, and therefore requires:

       1. No coercion, including no coercion resulting from the pressure to make trade on disadvantaged terms due to declining economic circumstances;
       2. Perfect knowledge of the outcomes;
       3. Perfect competition, in the sense that anybody making a trade has at the time of the trade an infinite number of alternate trades with marginally different properties in respect to all aspects of the trade; and
       4. No negative externalities.

       The argument presented by capitalists that markets are the most efficient form of distribution of goods (where efficiency is defined as Pareto Optimality) assumes these conditions, and therefore they are the implicit requirements that a market be 'free' as assumed in their arguments.  It is blindingly obvious that unregulated markets are not always, indeed are not typically free in this sense.  IMO, the principle economic role of governments is to regulate with a light touch to ensure that markets are as 'free' as possible (using my special definition of 'free').  Further, it is evident that 'pareto optimality' is not the same as a maximum utility outcome, and hence not the desired policy outcome for any government working 'for the people'.  Specifically, income disparities decrease the utility function of a market outcome; so governments should also work to decrease income disparities, and to increase individual control of economic activity.

       On top of all the above, I am a conservative in the original sense that I believe that change should be implimented gradually, except where it must be made with the utmost urgency.  That is because the more rapid the change, the more harmful side effects, and also the greater probability the outcome will not be the intended outcome.

       I have, until now, avoided stating my political views on public forums lest they distract from the discussion of climate science.  However, I state them here so that you can see that I am not against radical change to the international order, to national systems of governance, or to the economic order.  On the contrary, I am strongly in favour of just those - and it is highly probable the OPOF would agree with many of my proposed changes if I detailed them.  What I am very strongly against is making any of my (or anybody elses) proposals for such changes a precondition on tackling climate change.  We do not have sufficient time for that luxury.  Regardless of whether current systems of governance or economics in the US or elsewhere are favourable for tackling climate change, we are saddled with those systems now, and our strategy to respond to climate change must be based on the fact that those current conditions are the conditions in which we must proceed.

       If we do not accept that, we shackle ourselves with an initial step in tackling climate change of 'setting up the right conditions' to tackle climate change.  That in turn requires implimenting reforms that will be even more resisted than a carbon tax; and which currently have no political momentum (in the US and Australia at least).  In other words, it is a recipe for failure.  Even if we take the initial steps against AGW we can take while preparing the ground for later more radical changes, we have greatly increased the difficulty of our political task while giving climate change deniers rhetorical ammunition for their conspiracy theories.  

       In essence, if OPOF or Naomi Klein are right, then it is already too late to tackle climate change and we are committed to >2 C world.  The first thing to realize is that, if that is the case, we still need to do our best to reduce emissions - and our most rapid way to do that in the short and medium term is through the current systems of governance, and the current economy by implementing a carbon tax/ emissions trading scheme plus some regulation and funding of renewable energy research.  The reason we need to do that is that though 2 C is already bad, 2.5 C is still much better than 3 C, which is much better than 3.5 C.  Every gigatonne of reduced emissions is a win for future generations.

       Second, as it happens there are good reasons to think Naomi Klein and (especially) OPOF are not right.  First, as I understand it, there view that the US and other first world nations need to reduce emissions at greater than 4% per annum (and hence faster than is compatible with economic growth) is premised on assumption that first world nations should make a greater effort to tackle climate change (which they largely have caused) than third world nations (who will be disproportionately the victims).  While I agree with that, that is a political view not shared widely in the West, and is not the basis of current plans to tackle global warming.  It is not a necessity for tackling climate change, but only a necessity for tackling climate change fairly.  And while tackling climate change unfairly is very undesirable, it is not a undesirable as starting world war 3, as would be necessary to force the US government to abandon capitalism against its own will, and the will of its people as OPOF proposes.

       Further, the physical reduction of emissions in the US or other western nations faster than 4% per annum is only actually required if we prevent emissions trading between first world and third world nations.  In a fair world, any nations with current per capita emissions less than India would not currently be required to reduce emissions.  Indeed, would be allowed to expand them initially for several years.  That expanded emissions allowance could be traded to first world nations with the money funding renewable energy based economic expansion.  That in turn allows the first world nations to meet their targets with ongoing physical reductions in the order of 2% per annum, ie, at levels that are consistent with continuing economic growth. 

       In short, OPOF and Naomi Klein's approach is only necessitated by treating 2 C as a hard barrier, which it is not, by an optional (if ethical) decision about reduction targets, and a further decision about administrative methods that is also optional, and not based on ethical considerations.

       I hope this explains things better.

24883. barry1487 at 12:04 PM on 29 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       I'd be interested to see the results broken down according to who thought/didn't think they were a climate expert.

24884. barry1487 at 11:36 AM on 29 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       gws, a bit of googling helps.

24885. barry1487 at 10:29 AM on 29 March 2016
       Global Warming Basics: What Has Changed?
       

       Good question. If this were all the data we had we might be misled. But because it's not all the data we have, we don't interpet just from this subset, we use more to test it.

       Having limited stats skill, I'd test with incrementally more annual data to see if the trend changed much and the statistical significance wavered. If so, I'd say that the period selected had spurious statistical significance.

       I'd also make sure that I only used complete years, in case there's a residual annual cycle that, despite anomalising, could skew the results for such a short time period. As it happens, Jan 2011 - Dec 2015 also produces a stat sig trend for that data set. (You also get one for 2008 to present, but not to Dec 2015)

       I'd also regress that period (and a longer period), detrend and look for outliers, which I'd see in the last months of the analysis. Then I'd explore the possibility of a physical explanation (internal variability) to explain the jump at the end.

       I'm not sure that answers your question, though. I'd guess there is a different, perhaps more sophisticated statistical analysis that could demonstrate that the statistical significance for that period was probably spurious.

24886. nigelj at 08:49 AM on 29 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Tom Curtis.

       You write some good posts on other topics. However on this one I'm trying to get some understanding of what you are saying, because its far from clear, in any respect.

       For the record I'm an economic and political moderate who would rather modify capitalism than try some completely new system. However Naomi Klein does make some good criticisms of how capitalism is making reducing emissions difficult. I assume you are aware of her views, so I would appreciate your brief comments, so I cant get a handle on what you really believe.

       It is also not clear what emissions reduction strategy your are promoting. I seem to recall you saying trading in carbon credits? But these emissions trading schemes are working too well.

       However perhaps you see these schemes as likely to be the most palatable to the public and business community?

       In my view the best scheme in functional terms would seem to be carbon taxes, although this might be politically harder to sell?

       I think we also need direct government regulation of what energy mixes power companies follow.

       However I would like to know exactly what you are promoting.

24887. Kevin C at 06:12 AM on 29 March 2016
       Global Warming Basics: What Has Changed?
       

       I'm very happy to see that the classical mistake of assuming that a non-significant trend is evidence of there being no trend (i.e. the null hypothesis fallacy) has been avoided. Barry explained that quite clearly.

       To recap, null hypothesis tests are assymetric. We can prove the presence of a trend (that is significantly different from zero), but not the absence. The test can only say "yes" or "I don't know".
       
       So here's the next step. If we look at the trend since 2011 (in this case in GISTEMP, some other datasets and periods also work), we see a 5 year trend which statistically significantly different from zero.

       

       As the period gets shorter, it gets harder and harder for the significance test to give a 'yes' - it almost always says 'I don't know'. But in this case it says 'yes'.

       In this case our intuition would probably tell us that this is not compelling evidence of a global warming trend. For a start, it is more than 4 times the expected global warming signal. So how do we interpret this result?

24888. gws at 03:19 AM on 29 March 2016
       New survey finds a growing climate consensus among meteorologists
       

       John, what about the rest? 29%+38%+14%+5% = 86% < 100%

       Could you also provide a link to the results when available?

24889. Tom Curtis at 01:02 AM on 29 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       OPOF, @17, has grotesquely and serially misrepresented my claims.  Most grotesquely, he purports my defence of incremental changes under the current international system with current national forms of government as being sufficient to tackle global warming somehow commits me to un elected international organizations taking over control of recalcitrant governments.  Nor does he seem to recognize that that commits him to a totalitarian system.  Consequently I no longer consider him a protagonist for rational discuscion.

       For those who might by in the slightest persuaded by OPOF, may a recommend that he detail his timetable.  How long to establish the international orgianizations with the power to overtake sovereign governments.  How long to provide income to arm the forces of that organization.  How long to recruit, equip and train its armed forces.  How long to take over the operation of recalcitrant sovereign governments.  How long, in fact, before we can take step one to actually tackling AGW.

       If he thinks that is not what it will take, he is welcome to specify the measures required to develop international cooperation sufficient to field a force capable of taking on the US armed forces with a reasonable prospect of success (which would require, at a minimum, the full cooperations of the EU, Russia and China, and result in a pyrrhic victory at best).  He can also specify how discussion of these options will not reinforce the opposition to action on AGW in the US, which is significantly fueled by conspiracy theories of just such courses of action.

24890. barry1487 at 00:31 AM on 29 March 2016
       Global Warming Basics: What Has Changed?
       

       billev,

       I have a difficult time believing that carbon dioxide at one part in 2500 parts of atmosphere has any role that influences the global temperature. There is just not enough there there.

       1 in 2500 parts arsenic to body weight would kill you. Pretty much instantly. Small changes can produce large effects. The 'hole' in the ozone layer was brought about by CFCs and other halocarbons that in sum increased by a few parts per billion.

       Most of the gases in the atmosphere are not greenhouse gases. So take out all the gases that do not contribute to the greenhouse effect. This is the effect we're concerned with. Now the amount of CO2 compared to the other GHGs is a much larger fraction. Not to mention that CO2, molecule for molecule, is a strong greenhouse gas. Different gases have a different 'power' as greenhouse gases. Takes quite a bit of work to lay all that out and figure CO2's relative contribution to the greenhouse effect - about 9% to 26%.

       Here's a figure worth incorporating. The concentration of CO2 in the atmosphere has increased by more than 40% from the time human industry began pumping it out since the industrial revolution. And there is no doubt that that increase is entirely anthropogenic.

24891. One Planet Only Forever at 00:25 AM on 29 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Tom,

       I most passionately disagree with your attitude that you would rather see humanity perish than have callous unscrupulous misleading people have their freedom of actions effectively limited. Anarchy and Chaos are not my vision of a better future. That would mean accepting the past 30 years of successful denial of climate science and 'defending it into the future and admiring any continued success the denial industry can develop'.

       The point you object to is the measures that "International Policy" required to address this issue will require in the current socio-economic-political system of 'individual pursuit of personal interest governing what goes on through regional temporary developed impressions of popularity and profitability'.

       It is rather curious that you would claim faith in it being developed then declare opposition to it.

       It has not developed through the past 30 years because of the successes of wealth, power and misleading marketing in the fatally flawed system that clearly fails to be interested in advancing humanity.

       I want a future for humanity. That requires systems that will effectively limit the damaging consequences of those among humanity who choose to only care about maximizing their enjoyment of their life any way they can get away with. Defending such people and labelling powers that would limit their ability to do damage "totalitarian" is rather inappropriate.

       I defend everyone's right to say what they want. However, I do not defend their right to get away with making stuff up that they prefer to believe or the resulting promotion of activity that impedes the advancement of all of humanity to a lasting better future.

       And I would support measures that effectively remove such people from positions of power and influence (and remove undeserved wealth from them), no matter how regionally popular they are able to become (temporarily) or any how sneaky they were about getting away with something unacceptable.

       That is nothing more than having rules and enforcement in socio-economic-political systems to ensure the games are won by deserving people, just as every sport ever developed had to develop ways to keep cheaters from 'winning through unacceptable actions', and just as every city has by-laws and every nation has criminal laws.

       Humanity needs global 'laws and enforcement' that would be imposed contrary to temporary popular and profitable nation interests. And it is becoming clearer that that will require being able to remove people from power who can be shown to have knowingly tried to impede the advancement of global humanity. If the US would impeach the likes of Ted Cruz or any other harmful misleaders that get away with being elected (and they have not done so yet so they appear unlikely to) there would be no need for 'totalitarian (your application of the term not mine)' international intervention (that you refer to as International Policy, which is just empty words if it isn't enforceable).

24892. barry1487 at 23:46 PM on 28 March 2016
       Global Warming Basics: What Has Changed?
       

       Maybe, MA. There are upsides to giving someone the benefit of the doubt. They may deserve it and you were too quick to judge. You get better at explaining things with practise, and at judging the level at which to pitch the explanation. Other people who bother to read the comments may learn something new or useful.

       Perhaps the most telling of his comment is @6 where he says "I am not talking trends I am talking temperature history."

       That told me that he doesn't know much about trends and how important it is to analyse them properly. Seems to me (right or wrong) he's read a few items on temp history, isn't too familiar with the general debate or the details, and might learn something useful through discussion. If not, no matter. Someone else may get some use out of the chat.

       Unless the only people reading down this far are belliv and the locals... but it's a big world and SkS is a fairly prominent cli-sci blog.

24893. MA Rodger at 19:00 PM on 28 March 2016
       Global Warming Basics: What Has Changed?
       

       barry,

       I don't think you should take the words of belliv too literally. Rather you need to take his entire set of comments as a whole.

       Perhaps the most telling of his comment is @6 where he says "I am not talking trends I am talking temperature history." His comments are redolent with talk of "pauses" and these he contrasts with the "spikes" which he sees correctly as being of no long-term relevance. But he also talks of "pattern" and it is this "pattern" of "pauses" (a 30 year pause which is inevitably followed by 30+years of warming and then another pause) which he sees as compelling, as the main feature of the entire temperature record (which he restricts to the years since 1880). Thus he is armed with the insight to predict that the period 2002-2032 will deliver the world another "pause," that any warming since 2002 is but a "spike," that any trend calculated over less than 60+ years is fradulent and that any physical basis for the way the universe works is but hokus pokus.

       It is safe to say that there is no arguing with that.

24894. Tom Curtis at 17:47 PM on 28 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       OPOF @13:

       "Essentially, the International Community would have to be able to 'remove from power' any elected representatives in a nation like the USA (or leaders of businesses) who would claim that already fortunate people should still be allowed to benefit as much as they can from actvity that produces CO2 from the burning of fossil fuels (or be able to convince a bunch of voters who are easily tempted to be greedy or intolerant to change their minds and choose not to try to get away with getting what they want even though they probably could collectively get away with it, for a little while, perhaps long enough that they enjoy the undeserved benefits in 'their lifetime'.)."

       It is this, totalitarian instinct that means I will never agree with you on this issue.  I would rather the world perish striving for greater democracy than that it retreat to totalitarianism to preserve a mere, grubbing survival.  Fortunately, however, that is a choice we need not make.

       That is leaving aside that as a matter of practical politics, no external power would be able to removed the government of the US (or China, or Russia) without bringing us to nuclear war.

24895. Tom Curtis at 17:36 PM on 28 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       dklyer @14, The Economist's article on the IEA announcement states:

       "The IEA’s provisional findings will fan a debate about whether global emissions have peaked. China, after all, is trying to rebalance its economy away from heavily polluting industries towards services. But analysts say two years is too short a period to be considered a lasting trend. What is more, the IEA is relying on data that many economists question. If China’s official growth figures are exaggerated, then it would not be becoming less carbon intensive as fast as it seems."

       It is evident from context that what is doubted is the growth rate in China, not the net emissions.  Ergo your skepticism about the result is not warranted.

       For what it is worth, a seperate research group was predicting in December of 2015 that CO2 emissions would in fact decline slightly on 2014 levels, as also reported in The Economist.  So, if anything the IEA's report on emissions is conservative relative to the appropriate experts.  I would not read too much into that both because the Global Carbon Project team were partly projecting, and because the IEA by its nature has the best data available on actual emissions from fossil fuels.

       With regard to the CO2 concentration, in the very short term, CO2 levels are largely driven by temperature.  A very large increase in Global Mean Surface Temperature (GMST) as occured between 2014 and 2015 will result in a large rise CO2 concentration, while a large fall in GMST will result in a small rise in CO2 concentrations (indeed a fall if there is not net emissions).  The flat CO2 emissions means, absent variations in GMST, we would have expected a 2 ppmv rise in CO2 concentration in each of 2013, 2014 and 2015.  The very sharp rise in temperature between 2014 and 2015 results in a significantly higher rise in CO2 concentration.  With flat emissions, the rise in 2016 will be slightly higher again if 2016 is hotter (as seems likely).  However, later cooler years will have a much smaller rise in CO2 concentration, even with flat emissions.

24896. dklyer at 15:03 PM on 28 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Tom@12, I read about the IEA release in the online version of the Economist and as much as I’d welcome some good news I’m not sure I agree. As the article stated, “the IEA is relying on data that many economists question.” Meantime actual measurements show a different story.

       From the Scripps Institute, Keeling Curve page, “The annual growth of atmospheric carbon dioxide (CO2) during 2015, above three parts per million (ppm) per year, was the largest ever recorded at the Mauna Loa Observatory in Hawaii, said climate researchers Wednesday. Independent observations by NOAA’s Earth System Research Laboratory and by Scripps Institution of Oceanography at UC San Diego show that not only did 2015 have the largest increase, but also that the annual increase was larger than two ppm for each of the last four years, another first.”

       Maybe you know how the IEA estimate is put together or whether other factors, such as decreasing natural sinks, might affect the CO2 measurements? I’d listen to reasonable arguments but, for now, I’m skeptical.

24897. barry1487 at 14:50 PM on 28 March 2016
       Global Warming Basics: What Has Changed?
       

       belliv,

       Here are a couple of references examining mid-century flat/cool trend.

       https://www.skepticalscience.com/global-cooling-mid-20th-century-advanced.htm

       http://web.archive.org/web/20080501064616/tamino.wordpress.com/2007/08/17/hemispheres/

        

       And a more technical commentary on one paper, adding background detail:

       http://www.realclimate.org/index.php/archives/2009/04/yet-more-aerosols-comment-on-shindell-and-faluvegi/

       There are many factors affecting climate on various time scales. The questions you pose about fluctuating climate over the last 150 years or so have been long investigated. I hope you're not close minded as some here have suggested, and that you're curious enough to learn more about that aspect.

       (Excuse the lengthy response/s. Answers to your questions may be given in a paragraph, but probably not to the satisfaction of a truly skeptical mind. Each of us has to estimate how much detail is helpful)

24898. One Planet Only Forever at 13:51 PM on 28 March 2016
       Dangerous global warming will happen sooner than thought – study
       

       Tom,

       Faith in a system governed by 'temporary regional or tribal popularity and profitability among a current generation of humanity' effectively limiting the challenges it creates is not justified. The popularity of 'a better personal life in a person's lifetime' is a very powerful tool for people who would choose to abuse misleading marketing to prolong their ability to get away with actions they can understand are unacceptable.

       Your final point “International policy settings are not at a stage where that is yet likely, but they are not far off.” is unjustified wishful thinking. In the late 1980s the global community was also very close to acting responsibly to limit the challenges created for less fortunate people and for future generations ... but we all know how the last 30 years have gone ... bigger problems created with more wealthy and powerful troublemakers developed (not all wealthy powerful people are undeserving trouble makers, but many of them clearly are).

       The challenge today did not need to be as big as it is. All that was required was for the undeserving more fortunate, wealthier and more powerful people on the planet, people who gambled on getting away with less acceptable ways of living and profiting, to admit they deserved to lose their bets, to admit they did not deserve their perceptions of prosperity.

       The 'system of competition for maximum reward in an individual's lifetime is the real problem, creating mainly problems and few real sustainable solutions (if it creates any that can win in the popularity and profitability game made up by those who gamble on getting away with less acceptable ways of doing things it is almost completely by accident)'. The system has a clear track record of developing and prolonging activity that is understood to cause troubles that are faced by 'others', particularly those in future generations.

       I have previously shared this quote from “Our Common Future”, a UN Commission Report published in 1987, but it can never be repeated often enough.
       “25. Many present efforts to guard and maintain human progress, to meet human needs, and to realize human ambitions are simply unsustainable - in both the rich and poor nations. They draw too heavily, too quickly, on already overdrawn environmental resource accounts to be affordable far into the future without bankrupting those accounts. They may show profit on the balance sheets of our generation, but our children will inherit the losses. We borrow environmental capital from future generations with no intention or prospect of repaying. They may damn us for our spendthrift ways, but they can never collect on our debt to them. We act as we do because we can get away with it: future generations do not vote; they have no political or financial power; they cannot challenge our decisions.
       26. But the results of the present profligacy are rapidly closing the options for future generations. Most of today's decision makers will be dead before the planet feels; the heavier effects of acid precipitation, global warming, ozone depletion, or widespread desertification and species loss. Most of the young voters of today will still be alive. In the Commission's hearings it was the young, those who have the most to lose, who were the harshest critics of the planet's present management.”

       The only way the required International Policy Settings will happen is the demise of the system that is driven madly by temporary regional and tribal popularity and competition to maximize personal reward. Unlike action for Ozone reduction (something that was actually less effective than it needed to be), there is a massive amount of personal desire in powerful pockets around the planet that can be mobilized to prolong the ability for undeserving people to 'enjoy creating a bigger problem by getting away with things they do not deserve to be able to get away with'.

       The belief that individuals being free to do as they please in pursuit of a better present for themselves will advance humanity to a better future, or even allow humanity to have a future, deserves to be shattered. And it will be shattered if the required effectively enforced International Policies can be imposed on all nations, including the nations that elect leaders who would be regionally popular because they refuse to behave responsibly.

       Essentially, the International Community would have to be able to 'remove from power' any elected representatives in a nation like the USA (or leaders of businesses) who would claim that already fortunate people should still be allowed to benefit as much as they can from actvity that produces CO2 from the burning of fossil fuels (or be able to convince a bunch of voters who are easily tempted to be greedy or intolerant to change their minds and choose not to try to get away with getting what they want even though they probably could collectively get away with it, for a little while, perhaps long enough that they enjoy the undeserved benefits in 'their lifetime'.).

24899. barry1487 at 13:27 PM on 28 March 2016
       Global Warming Basics: What Has Changed?
       

       belliv, you can do a test for whether there has been a pause in warming by comparing the uncertainty estimates for various periods (ie, prior to and after 2002). If you understand me so far regarding the uncertainty estimates, I'll lay out a fairly easy test you can do with apps available on the web, such as the one I used to generate these graphs.

       Here's the link to the graph generator if you want to have a look at that.

       http://www.ysbl.york.ac.uk/~cowtan/applets/trend/trend.html

       You can access the same app near the top of the left hand side side bar on this page, labeled 'Trend Calculator'.

24900. barry1487 at 13:13 PM on 28 March 2016
       Global Warming Basics: What Has Changed?
       

       To compare, here is what a trend estimate that shows warming looks like. Note that the trend is positive (warming), and the uncertainty is smaller than the trend. In other words the uncertainty is only to do with the degree of warming - it doesn't include a zero (or negative) trend estimate.

       Full time period for Remote Sensing System - Jan 1979 to Dec 2015:

       

       Now the trend is anywhere between 0.06 and 0.19 C/decade. The uncertainty does not include zero or negative values, only positive. We call this a 'statistically significant' trend.

       Let's do the same for NASA, same period.

       

       Trend is anywhere between 0.12 and 0.20 C/decade. The uncertainy doesn't include zero or negative values. The trend is statistically significant, unlike the trend estimates in the previous post.

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