Recent Comments

Prev  137  138  139  140  141  142  143  144  145  146  147  148  149  150  151  152  Next

Comments 7201 to 7250:

7201. MA Rodger at 01:25 AM on 3 July 2020
      Hansen's 1988 prediction was wrong
      

      Nylo @56,

      I'm with you part the way on your first point. (And your second point, the comparison with Scenario C; that seems a step too far.)

      On the first part of the first point, the value given for Scenario B CO2 increase post-2010 in Hansen et al (1988) (PDF p21) is 1.9ppm/y, the MLO-measured CO2 ran at 2.4ppm/y and that does translate into being 26% above Scenatio B.

      From here, I initially assumed you are looking at Fig b1 which gives a value for CO2 at 1.2 and a combined value for CFCs & CH4 of 0.46 or 38% of the value given for CO2, or 2.6x the given CO2 value. So, firstly, I am not sure where you get the "4 times the sum" and , secondly, I'm not sure why you woud be taking numbers from Fig b1. Indeed, I'm not exactly sure what Fig b1 is meant to be demonstrating. The values are described as "arbitrary" but, in the case of CO2 give a value of non-feedback warming for a doubling of CO2 (315ppm→630ppm). The CFC11&12 is for 0→2ppb each and the CH4 also for doubling although there are complications with such a stand-alone value for CH4.

      I think you should be examining Fig b2 which provides the values for the decadal increments of forcing - for the 1980s CO2 0.08, CH4 0.03 & CFC11&12 0.2. Thus, back-of-fag-packet, the 2010s CO2-above-ScenarioB of +0.5ppm/y equates to a third of the 1980s annual increase or 0.027 of the 0.8 from figb2. If you venture to examine the NOAA AGGI numbers, you'll find CFC11&12 today remain at 1990 values and the CH4 increase post-2010 is a third the 1980s increase suggesting forcing below ScenarioB of -0.2 & -⅔ of 0.3 = -0.4. So by that reckoning, the additional 26% CO2 forcing would sit below the lost CFC & CH4 forcing, not "ABOVE".

      Or a simpler analysis using just AGGI, the missing CO2 forcing 2010-on would be 20.6% of the additional CO2 forcing = +0.065Wm^-2, or perhaps double that for all three of the three post-1990 decades combined. The CH4/CFC11&12 forcing through the 1980s was +0.126Wm^-2 which would continue at or above that value for the following 3 decades in Scenario3, so totaling +0.378Wm^-2. But the actual forcing is given over this period 1990-2019 as +0.056Wm^-2 so relative to ScenarioB forcing that is -0.322Wm^-2 from CH4/CFC11&12 and with the extra CO2 forcing included yielding (-0.322 + 2x0.065 = ) -0.192Wm^-2. It works out again with less forcing, not "ABOVE".

7202. Eclectic at 22:35 PM on 2 July 2020
      Models are unreliable
      

      ClimateDemon @1173 ,

      Your "CO2 control knob" ideas fall flat, because you have made the critical mistake of looking at climate models only.

      If you look at the bigger context, and examine the paleological evidence, then it becomes very evident CO2 has exerted a major "control knob" effect on planetary climate.  That is also reinforced by the empirical evidence of modern historical data.

7203. ClimateDemon at 21:53 PM on 2 July 2020
      Models are unreliable
      

      I agree that over the past century, the state-of-the-art of modeling and simulation has grown by leaps and bounds, especially since the development of supercomputers in the 1980s. They have been valuable tools for research and development in general, not just climate science. It should be noted, however, that such models are meant to aid scientists in their understanding of certain phenomenon, possibly identifying causes and even making short-term general predictions. They are NOT meant for government use to generate long-term predictions (which no model can do reliably), and use them as a basis for carbon taxes and regulations.

      In order for a model to accurately predict climate change, it must take into account the dynamics of atmospheric fluid motion, realizing that the atmosphere is not in thermal equilibrium. [If it were in thermal equilibrium, there would be a uniform temperature and humidity over the entire surface with no winds nor storms.] This involves solving the time-dependent equations of mass balance (equation of continuity), momentum balance (Navier-Stokes equation), and energy balance which is what is done in the climate General Circulation Models. This is a set of partial differential equations that are first order in time which are generally solved in time by some type of finite difference method given the initial conditions. Note that the terms "forcings" and "feedbacks" aren't even in the vocabulary. Therefore, if there is H2O vapor in the air, its greenhouse effect is accounted for in the energy balance equation. If there is CO2 in the air, its greenhouse effect is also accounted for in the same energy balance equation. The contributions from the H2O greenhouse warming will, of course, be much greater than those of the CO2 warming, but there is nothing to indicate that CO2 has any "control knob" effect.

      The only model that predicts AGW and the CO2 control knob is the one used by Lacis et. al. 2010, the staff here at SkS, or wherever AGW is preached. This is a highly oversimplified, zero dimensional model in which the earth's temperature is represented by a single scalar value T, and the H2O vapor concentration is determined by the Clausius-Clapeyron equation at temperature T. This means that the entire globe is rigidly held to this one fixed value of temperature and corresponding value of humidity, which we know is false. Furthermore, it assumes (through the Clausius-Clapeyron equation) that H2O in its vapor state and condensed states are in constant thermal equilibrium with each other, which is also false. At this point, AGW advocates generally understand the (invalid) argument as to how CO2 becomes the controlling GHG even though it is much weaker than H2O vapor, so I won't repeat it here. In general, those who preach the doctrine that a non-condensable GHG can only be a “forcing” and a condensable GHG can only be a “feedback” have been duped by the fallacies and self-inconsistencies of this “carbon-in-control” model. Another false manifestation of this model is the frozen earth scenario where all CO2 is eliminated, and as a result, there is no non-condensable GHG in the atmosphere to provide the temperature forcing needed to put H2O vapor, the stronger GHG, in the air. As a result, the entire terrestrial greenhouse effect collapses since there isn’t any of either GHG in the atmosphere, thereby leaving an iceball of an earth behind. Aside from the highly anti-intuitive nature of this prediction, it would be totally impossible to test it.

      So what should we do about this CO2 control-knob theory? Do we say "It's what the science says, so we must accept it since we are scientists.", or do we do some critical thinking and say "It took several false assumptions to make the control knob argument, so there are very likely problems with it."?

      Moderator Response:

      [DB]  As this iteration of this user account is new, please read the Comments Policy linked near each Comment Box.  Pay particular attention to the prohibition against sloganeering and note that assertions made must be accompanied by citations to credible evidence, with the more egregious the claim the higher the Burden Of Proof is upon you, the asserter, to fulfill that burden.  Simply saying "ugh-ugh" is insufficient.  Please compose future comments to better comport with the Comments Policy.

      Sloganeering snipped.

7204. Nylo at 21:25 PM on 2 July 2020
      Hansen's 1988 prediction was wrong
      

      Thank you very much for the update.

      MA Rodger @54, thanks a lot for the explanation. You say that the increased CO2 emissions compared to scenario B is compensated by the drop in emissions of CFC and CH4. Page 21 of the PDF of James Hansen's article, which is part of Annex B, shows (literally) that in Scenario B he expected a constant increase of 1.9ppmv of CO2 yearly from 2010 onwards. But the average yearly increase of CO2 that we have witnessed since 2010 is 2.4ppmv yr^-1. That's a whopping additional 26%. In the same page, James Hansen's article has a graphic showing the relative contribution of the different gases, in which CO2 contributes 4 times the sum of the contributions of CFCs and CH4. Even if we had 100% halted the increase of these gases as soon as 1988 and reduced their influence to zero, the additional 26% of CO2 would put the total influence ABOVE the combined effects of all gases predicted by Hansen. But not only have we not reduced the emissions of those gases to zero, the concentration of both gases is today quite higher than in 1988, which must have a warming effect.

      Scenario C also shows that the biggest influence for the dramatic drop in expected temperatures compared to Scenario B is CO2, because it is CO2 that experiences a huge change compared to Scenario B whereas CFCs and CH4, while smaller, do not show such an abrupt difference. So clearly Hansen attributes to CO2 a much bigger effect on temperatures than the other 2 gases. And he expected a waaaaaay smaller increase of CO2 in his scenario B compared to what we have witnessed, which is more according to Scenario A. It may not be fair to expect temperatures to evolve like in Scenario A as the CFCs and CH4 increases are smaller, but we should expect something between the 2 scenarios. And what we get is in temperatures is below scenario B. We are approximately 0.3ºC cooler than what would have been be expected by Hansen's models, back in 1988, with the known GHGs evolution as input.

7205. michael sweet at 20:45 PM on 2 July 2020
      Hansen's 1988 prediction was wrong
      

      Nylo@53:

      Skeptical Science is staffed completely by volunteers.   It turns out that few people can find the time to update old posts' graphs to reflect new data.  That is life.

      If you want to find out what the updated graph would look like you might go to the Real Climate Climate model comparison page, which is updated yearly.  Their up to date graph looks like this:

      

      Measuring carefully with my eyecrometer I findl that the data from 2017-2019 makes the model look better.  If the writers were attempting to cherry pick their data they did a poor job and left off data that they should have included.  

      It looks like 2020 is going to be a very hot year.  Perhaps when RealClimate updates their graph next January you can come back here and show us what the new graph looks like.

7206. MA Rodger at 20:19 PM on 2 July 2020
      Hansen's 1988 prediction was wrong
      

      Nylo @53,

      The graph Fig 1 of the 'basic' OP above without the post-2016 GISS data does indeed suggest a more robust record of warming than would be the case with 2017-19 data added, but I wouldn't go so far as to describe it as being "a very red and tasty cherry". The climate forcing 1988-to-date is a little short of Scenario B and so also is the trend in global temperature. (GISS data relative to 2016, the following years sit 0.09ºC, 0.17ºC, 0.04ºC below 2016 with 2020 potentially topping 2016.)

      Regarding the forcings relative to 1988, Fig 4 of the 'advanced' OP above plots 'actual' relative to the scenarios of Hansen et al. These derive from annual emissions of all anthropogenic forcings as does the 1.5% you quote for Hansen et al for Scenario A. The paper's Appendix B describes in more detail the acceleration in emissions for the various gases in Scenario A and the tailing-off that accelerations in Scenario B. 

      I'm not sure you are describing this change in annual emissions.

      I suspect you are looking at either accumulative CO2 emissions since pre-industrial times (an increase of 69% since 1988) or solely annual FF CO2 emissions (an increase of 67% although that is reduced to 57% if LUC CO2 emissions are included). The numbers I quote are calcuated from Global Carbon Project data.

      The NOAA AGGI gives the annual forcing data from GHG emissions which shows today's annual increase in forcing is slightly reduced relative to 1988 (this the net effect of increasing CO2 emissions balanced by the drop in CFC emissions and the 'hiatus' in CH4 emissions). In more detail, the annual forcing increase dropped from the 1980s into the 1990s but has since been on the rise again. So the forcing accounted in the AGGI are running below the Hansen et al Scenarion B but AGGI does not include any change in negative forcing from aerosols which will have boosted net forcing a bit over the period (as shown in that Fig 4 of the OP).

7207. Nylo at 16:44 PM on 2 July 2020
      Hansen's 1988 prediction was wrong
      

      Dear friends of Skeptical Science, are you planning to update the graphic to show the data through 2019? Or can we assume that you only updated the graphic until 2016 because it proved to be a very red and tasty cherry to pick?

      As a separate question, why do you say that Scenario B was closest to reality? I mean, on what basis? I have read the Hansen paper through your link and Hansen was expecting our emissions to grow 1.5% per year in Scenario A, which would have led to a 52% growth by 2016 compared to our emissions in 1988. But our emissions have increased by a whopping 63% since 1988, which is far worse than what scenario A expected. So probably you are referring to something else appart from CO2 emissions to claim that Scenario B is "closest to reality". What is that sentence based on?

      Thanks a lot. 

7208. Tom Dayton at 16:11 PM on 2 July 2020
      Models are unreliable
      

      Deplore_This: I suspect you incorrectly believe that "climate models" are different from climate theory, which is why you do not want to take any of those courses that are not devoted to what you incorrectly think of as climate models. General Circulation Models (GCMs) are just instantiations of those theories in those courses and textbooks. So by learning those theories you will be learning about what you call "climate models." Please try reading Tamino's "Not Computer Models."

7209. Tom Dayton at 14:15 PM on 2 July 2020
      Models are unreliable
      

      Deplore_This: Perhaps the ISCA framework is what you want.

7210. Tom Dayton at 13:46 PM on 2 July 2020
      Models are unreliable
      

      Deplore_This: You should use one of the textbooks to inform you as you play with that model.

7211. Tom Dayton at 13:42 PM on 2 July 2020
      Models are unreliable
      

      Deplore_This: I strongly suggest you take some courses instead of merely reading the syllabi. if you refuse to do that, thinking you know too much already, then go ahead and skip the courses and dive into an open source model: https://www.giss.nasa.gov/tools/modelE/

7212. Deplore_This at 12:25 PM on 2 July 2020
      Models are unreliable
      

      @Dayton 1163, 1164 and 1165
      @ scaddenp 1166 and 1167

      Thank you for the responses. However, I had previously found and reviewed on my own the course syllabuses for your suggested courses before posting.

      Reading the syllabuses of these courses they include basic discussions of what GCM is but not how to do it. None of these courses give the student the opportunity to construct and run GCM and measure their predictive capability by hindcasting.

      I am candidly stating that I am a skeptic of these models and I’m trying to understand the science. I have been frustrated that everything I find is a consensus opinion on these models but I haven’t found anything that allows me to get under the hood and see how the models work for myself and to evaluate the predictive sensitivity of these models.

      I’m not looking for a book. I’m retired and have the time and the money to pay for the best university course I can take. I have the academic qualifications and professional technical knowledge and experience to dig deep into this. My problem is I haven’t found one. I’ve reviewed the curriculum of the top environmental science university programs and I haven’t found a single course. I am asking for a recommendation.

      Thank you again for your response but I still don’t know where to find a course that achieves my objective. I appreciate any assistance you can provide.

7213. scaddenp at 08:33 AM on 2 July 2020
      Models are unreliable
      

      I would also recommend that read the chapter in the IPCC WG1 report on evaluation of climate models before getting too far into the course. (chp 9 in the latest report).

7214. scaddenp at 08:26 AM on 2 July 2020
      Models are unreliable
      

      Deplore_This: Not exactly sure what you mean by "climate temperature models referenced by the IPCC" but I assume you mean the GCMs used by CMIP to predict future climate (of which temperature is but variable that can be extracted). If this is the case, then note that these are the best means we have available to predict future climate, but by themselves say nothing about the validity of anthropogenic climate change. They could be completely wrong do to some fundimental algorithmic error which would affect their ability to infer the future, but say nothing about the accuracy of the physic of anthopogenic climate change.

      The science does depend on other models (but not necessarily computer models), especially the radiative properties of gases and the Radiative Transfer Equations in particular. These have real-world applications and the detailed work was initially done by USAF because laser-guided bombs depend on them.
      
      There are rather more direct ways of checking validity of science (eg empirical evidence). You can also directly measure the increase in surface irradiation. I rather suspect that you would agree that an increase in surface irradation because sun increased its output would warm the planet. The GHE can do that too.

7215. Tom Dayton at 07:23 AM on 2 July 2020
      Models are unreliable
      

      Deplore_This, you could also simply search the internet for climate modelling textbook, and you'll get a plethora of books.

7216. Tom Dayton at 07:07 AM on 2 July 2020
      Models are unreliable
      

      Deplore_This, also from that simple search of the internet I quickly found a course at the U. of Washington, Swedish e-Science Education (taught in English), several by MIT, University of California Santa Cruz...

7217. Tom Dayton at 06:55 AM on 2 July 2020
      Models are unreliable
      

      Deplore_This: I don't understand how you could have trouble finding courses. David Archer at U. of Chicago has an online course that starts today. It was the fourth result from my Duck Duck Go search for climate modeling course class online.

7218. Deplore_This at 05:57 AM on 2 July 2020
      Models are unreliable
      

      I am an anthropogenic climate change skeptic because I’ve read criticism of the validity of the climate temperature models referenced by the IPCC. I am not a climate researcher by training or profession and to satisfy my scientific curiosity I’ve been trying to find a university course in climate temperature modeling including CO2 sensitivity analysis. From my undergraduate degree I have an extensive background in operations research, mathematics, computer science and basic physics and chemistry courses for Engineers. So I can’t imagine there is any computer modelling that will be beyond my ability.

      I’ve looked at the undergraduate and graduate curriculum for the top US environmental science universities and have found only one course on climate modeling. Penn State offered METEO 523 in Spring 2020 and only 6 of 30 seats were filled and the course has been since dropped.

      Can anyone suggest a climate modeling course I can pursue? Sorry to ask here but I’ve spent a lot of time searching and have come up short.

      Thank you.

7219. Eclectic at 20:20 PM on 1 July 2020
      Is Nuclear Energy the Answer?
      

      Michael @156 ,

      I haven't seen Shellenberger's presentations favoring extensive usage of "nuclear" (and as you do, I strongly suspect it cannot be achieved in a timely & economic manner . . . and it would be a harmful diversion of resources that would much better be spent on "renewables").

      However, readers may have noted an article by Shellenberger titled: "On behalf of environmentalists, I apologize for the climate scare".

      But I am not in any way recommending his article.  Shellenberger's article is quite appalling in quality ~ it resembles the "holiest" of Swiss cheeses, in that it is burdened with a vast number of logical errors & misleading informations.   In short, a propaganda piece.   Although he appears to make an acknowledgement of AGW as a problem, he slants his message to the position that tackling AGW is non-urgent & can reasonably be postponed for decades (while other world problems get precedence).   Altogether, his article fits in well with the run-of-the-mill Denialist nonsense.  The same flavor, almost entirely !

7220. michael sweet at 12:29 PM on 1 July 2020
      Is Nuclear Energy the Answer?
      

      At post 90 in this thread I commented on a Shellenberger video.  Shellenberger is a paid shill for the nuclear industry.  His presentations are filled with falsehoods and misinformation.  

      I recommend you read Abbott 2012, linked in the OP.  Abbott is a peer reviewed critique of nuclear power.  Abbott shows that there is no hope of a significant (more than 5% of all power) amount of nuclear power in the future.  Shellenberger has not attempted to answer the issues raised by Abbott.   Who do you believe, a peer reviewed paper or an unreviewed paid shill? 

      I note that even Shellenberger only claims that 50% of current electricity (about 10% of all power) can be generated using nuclear power.  The remainder would have to be generated by renewables.

7221. Doug Bostrom at 06:26 AM on 1 July 2020
      Skeptical Science New Research for Week #25, 2020
      

      That's a remarkable story, David Hawk, depressing and yet hopeful. 

      Thank you for sharing it. 

7222. Doug Bostrom at 02:55 AM on 1 July 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      Thank you, BF— we'll sort it out. 

      [Fixed. The original report may also be found here: https://www.epa.gov/office-inspector-general/report-further-efforts-needed-uphold-scientific-integrity-policy-epa ]

7223. jhnwlk at 02:53 AM on 1 July 2020
      Is Nuclear Energy the Answer?
      

      Sorry for the misspelling...that would be Shellenberger

7224. jhnwlk at 02:47 AM on 1 July 2020
      Is Nuclear Energy the Answer?
      

      I'm looking for a critique of the case Michael Schellenberger makes for nuclear energy.  Would there be one in comments in this thread or anywhere else on the website?  

7225. djinghis at 21:35 PM on 30 June 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      @JWRebel The CDC

7226. MA Rodger at 21:00 PM on 30 June 2020
      It's only a few degrees
      

      Jasper @3, Yet another take.

      You write "I get that a few degrees make a huge difference. I don't fully understand why a few degrees matter so much." Although a huge difference is suggestive that it does matter, I read your meaning that you are after an authoritiative take on the effects of "a few degrees" and something with a bit of meat on it.

      Warming the globe by "a few degrees" will make a big difference to the climate system which has been previously reasonably fixed for millenia and so will bring unprecedented change for human civilisation. But providing an authoritative account of what that change will amount to isn't so easy.

      Will those "few degrees" be enough to stop the AMOC and plunge Europe into a mini-ice age, enough to broaden the Hadley Cells and turn the central US lands and the Mediterranean lands into deserts, to green the Sahara and turn the Amazon into a treeless savannah? The answers are not straightforward. There is no long list if definitive outcomes set out in the headlines of the IPCC AR5 Synthesis Report. The word "risk" features too often when IPCC describes such outcomes.

      

      But there are a couple of definitive temperature-related outcomes from AGW.

      One is that Greenland will melt out somewhere between +1ºC and +2ºC threatening serious sea level rise. (The IPCC AR5 puts the upper bound at +4°C which is rather a fudge. Antarctica's ice caps are similarly a threat but how quickly they will react to global temperature rise is not well enough understood to be so predictable.) Another is the habitability of the tropics for humanity and perhaps a third is ocean acidification which would be unprecedented in tens of million of years.

      If Greenland were to melt down (a process that once started will not stop as the top of the Greenland ice sheet today sits happily frozen high up in the cold upper atmosphere), the oceans would rise by over seven metres. This compares with the last six thousand years (which spans the period of human civilisation) when changes in sea level could be measures in centimetres. A seven metre rise would be a big problem as so much of our populations today live close to sea coasts. (About a third of humanity inhabit land less than 100 metres above sea level while the loss of both Greenland and Antarctica would raise sea levens 75 metres.) The melt-down of Greenland would take a few centuries to make its mark but the process certainly becomes unstoppable if global warming remains two degrees centigrade above pre-industrial.

      The "few degrees" global temperature rise that accompanied the warming from the last glacial maximum 20,000 years ago and the dramatic impact on climate has been mentioned up-thread. The change in climate resulting from another similar-sized rise in global temperature would be just as dramatic for humanity. If global temperatures rose by six degrees celsius above pre-industrial, it could perhaps be described as a "Steam Age" as the increase in wet bulb temperatures would make the tropics a death trap for humans outside air conditioning. And such a six-degree temperature increase by 2100 is within the projection of the Business-As-Usual scenario of the IPCC.

      The ocean acidification would rival that of the PETM 55 million years ago but would happen in decades rather than tens-of-millenia.

      There is a big pile of reason not to let AGW run beyond +1.5°C. The implications for humanity and for much of the biosphere will be catastrophic if we let AGW run. It's a bit like jumping off a cliff. Predicting the height it would require for the fall to split your skull open is not straightforward but that is no reason to consider jumping. Besides, when you fall it's the intracranial hypertension that usually kills.

7227. MA Rodger at 19:56 PM on 30 June 2020
      2020 SkS Weekly Climate Change & Global Warming News Roundup #25
      

      Given I have criticised Slarty Bartfast for the egregious level of error he achieves, I really should correct an error of my own up-thread.

      Due to a spreadsheet error, the table of decadal averages within my comment @29 is entirely wrong, along with the associated result SD=0.14°C. The spreadsheet calculation corrected, I can now concur with Slarty Bartfast on his calculated decadal SD=0.28°C. (I calculate SD=0.287°C.)

      The same does not go for other of his calculated SD for the Christchurch NZ monthly raw temperature data, these scaled from the graphic @21 above. (And of course, this data shouldn't be used for any reason in their raw state and and the SD shouldn't be calculated without consideration of the trend.) The comparison runs as follows:-
      Av'ged period (months) .. .. My SDs ..... .. His SDs
      1 .. ..... ..... ..... ..... ..... ..... 1.58°C ..... ..... 1.06°C
      3 .. ..... ..... ..... ..... ..... ..... 1.30°C ..... ..... 0.76°C
      6 .. ..... ..... ..... ..... ..... ..... 0.60°C ..... ..... 0.62°C
      12 . ..... ..... ..... ..... ..... ..... 0.49°C ..... ..... 0.51°C
      24 ' .... ..... ...... ..... ..... ..... 0.44°C ..... ..... 0.43°C
      60 . ..... ..... ..... ..... ..... ..... 0.34°C ..... ..... 0.34°C
      120 ...... ..... ..... ..... ..... ..... 0.29°C ..... ..... 0.28°C
      It is evident that the SD calculation does not yield the straight line that Slarty Bartfast insists they do. And there is a pile of other methodological reasons for not attempting to extrapolate the data to provide an SD for an averaged century-long 1200 month period.
      But as Slarty Bartfast does, let us not ignore all those problems.

      Instead consider the situation if, as Slarty Bartfast insists is the case, for 1200 month period there were actually SD=0.18°C. What is then easy to demonstrate are the errors in his argument that a +1.0°C increase in global average temperature between two consecutive centuries is "entirely possible" indeed "probable," this "due to natural variations resulting from chaotic behaviour within the climate system," or "mostly" so.

      Slarty Bartfast @30 asserts that this SD=0.18°C would have a 95% probability of a 4-sigma fluctuation or "0.7 °C minimum". There are however a couple of fundamental errors in this bold assertion.

      Firstly, a 20:1 chance is not what anybody would describe as "probable." Such odds are usually seen as being "improbable."

      Secondly, for a normal distribution, the odds of seeing an increase of +0.7°C, or a positive increase equal in size to 4xSD, is not 20:1 but roughly 800:1. It is actually highly improbably. And we have the data to demonstrate this point.
      The raw monthly data used by Slarty Bartfast can be averaged over those different periods and so the number of actual occurances of a +4xSD fluctuation can be totted-up. So, how many times do we find the increase between two data points is greater than 4x the calculated SD? Despite over 3,000 attempts, we don't find even one. The best we can do is 3.4xSD (which for a normal distribution is about 10x more likely than 4xSD).

      Av'ged period (months) .. .. 4 x SDs ..... .. Dev (& xSD) achieved
      1 .. ..... ..... ..... ..... ..... ..... .. +6.33°C ..... ..... +5.16°C (3.26)
      3 .. ..... ..... ..... ..... ..... ..... .. +5.20°C ..... ..... +4.44°C (3.42)
      6 .. ..... ..... ..... ..... ..... ..... .. +2.40°C ..... ..... +2.06°C (3.44)
      12 . ..... .... ..... ...... ..... ..... .. +1.96°C ..... ..... +1.30°C (2.65)
      24 . ..... ..... ..... ..... ..... ..... .. +1.74°C ..... ..... +1.18°C (2.70)
      60 . ..... ..... ..... ..... ..... ..... .. +1.36°C ..... ..... +0.87°C (2.55)
      120 ...... ..... ..... ..... ..... ..... .. +1.15°C ..... ..... +0.43°C (1.51)

      As would be expected, the longer the averaged period, the fewer the data points, the smaller the probability of consecutive 4xSD fluctuations between consecutive data points.

      So, even if it were correct to use raw data, even if the presence of trends were ignorable, even if the SD for century-long smoothing could be obtained; even if all this were so, we find Slarty Bartfast's chosen data does not show what Slarty Bartfast says.

       

7228. Eclectic at 17:22 PM on 30 June 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      JWRebel @3 ,

      please be more clear about the thrust of your question.  Unless you have been oblivious the many reports, since middle of last century, of compromised scientific integrity and/or corruption - most typically in the medical/biological field - then your question seems to be discursively open-ended.   (Not much fudging takes place in the hard sciences ~ mainly just poor analysis/interpretation.)

      IMO the outstanding point of the article is to emphasize the recent big surge in "top down" interference in scientific integrity.   A huge surge ~ almost comparable with the ancient Lysenko scandal of Stalinist fame/infamy.   COVID-19 , climate , weather reporting . . . take your pick.

7229. bf at 13:38 PM on 30 June 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      Broken link (URL appears twice) at: "A May 2020 report published by the EPA’s Office of Inspector General"

7230. JWRebel at 12:53 PM on 30 June 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      @ doug_bostrom

      Those are all about climate change, not the COVID-19 epidemic which has seen the Lancet and Journal of New England Medicine scramble to retract peer-reviewed articles based on fraudulent data. That's why I'd like to know what exactly the author has in mind as clear examples of compromised scientific integrity and/or corruption.

7231. Doug Bostrom at 05:59 AM on 30 June 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      JW, the answer to your question is in plain sight in the article, in numerous places:

       "A June 15 article in The New York Times..."

      "A May 2020 report published by the EPA’s Office of Inspector General..."

      "Under significant pressure from the White House, the acting head of NOAA, Neil Jacobs, subsequently issued an unsigned statement chastising the Alabama NWS scientists and backing Trump’s false claim. This behavior by the agency leadership violated principles in NOAA’s scientific integrity policy."

      Et al. I won't reproduce the entire article above down here in comments— it makes a little more sense for you to read it. 

7232. JWRebel at 23:12 PM on 29 June 2020
      CSLDF: Why We’re Concerned About Scientific Integrity Policies
      

      The COVID-19 pandemic tragically highlights the dire and immediate threats to public health that can result when the culture of scientific integrity at research institutions is ignored or fails.

      An example of compromised institutions would be in order. I don't regard this as trivially obvious.

7233. One Planet Only Forever at 03:51 AM on 29 June 2020
      2020 SkS Weekly Climate Change & Global Warming News Roundup #26
      

      The problem is not Facebook. The problem is competition for popularity and profit.

      The pursuit of popularity and profit drives the development of many understandably harmfully incorrect things, and it drives the resistance to correction of those incorrect things.

      Responsible Governing is the solution, but keeping popularity and profit from influencing Governing is very challenging.

7234. One Planet Only Forever at 02:38 AM on 29 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      People who want to be helpful should keep the Big Picture in mind.

      The Big Picture is the need for Humanity to have a lasting and improving future. And that requires maintaining the system that humans developed within - the environment and the robust diversity of life constrained by the sustainability of the limits of this amazing planet (or any locations humanity spreads to). That will require expanding awareness and improving understanding to help achieve the Sustainable Development Goals, all of them. And that will require significant corrections of many things that modern-day humans have developed a liking for benefiting from, especially correcting the socioeconomic-political systems that have developed.

      Achieving many of the SDGs is made harder by rapid human caused climate change. So limiting the total human caused climate change is one of the most important things for humanity to work on. That leads to the understanding that the lack of responsible correction by the highest consuming and impacting portion of the global population, particularly through the past 30 years, has created the daunting current day challenge of limiting the total climate change impact to less a maximum of 2.0 C (an understandably harmful level of impact) with a need to try to limit it to 1.5 C (also a harmful, but far less harmful, level of impact).

      I would add that after succeeding in achieving the upper limit of climate change impact (hopefully closer to 1.5 C), humanity needs to rapidly reduce the atmospheric CO2 concentration to 350 ppm.

      It is possible, even highly likely, that many wealthy powerful people who have been resisting the required corrections understand that making the problem worse, delaying the corrections, would increase popular support for resistance to the increasingly harsher required corrections. The lack of significant penalties for people like that, a lack of responsible Governing of those who will not responsibly Self-Govern, is a developed systemic problem that needs to be corrected. The undeserving among the Perceived Superiors must be identified and corrected. That will require Peers to correct their harmfully incorrect Peers. An alternative is a Rebellion by the lower status, and that is not something to look forward to.

      Limiting the consumption and impacts of the most consuming and highest negative-impacting portion of the population, and getting every member of the most fortunate portion of the population to lead the development of truly sustainable ways to live well, is a very effective path to a lasting improving future for humanity. It is potentially the most effective way and may be the only path to a better future for humanity.

      The sum of the impacts of each individual is the math that needs to be done.

      Studies in ethical philosophy such as Utilitarianism identify the problem of a single very high consuming and impacting person ruining things for everyone else while the overall impression of the total, excluding any consideration of inequity and injustice, looks good. One bad apple can tempt others to join them in personally benefiting in unsustainable and harmful ways.

      What has developed today is: Over-population, Over-Consumption, and Harmful Unsustainable Activities that are popular and profitable. And each of those can be understood to be the result of Selfish people pursuing benefits in harmful, unjust and inequitable ways. And those unjust inequitable developments include developing the systems, including laws and their application, that produce the harmful results and resist correction.

      The Systems that have developed need to be corrected to Equitably and Justifiably: Reduce the total global population, reduce the total consumption, and eliminate activity that does harm to Others (end actions that are unjust, and end systemic inequity). That will require the Einstein Quote at the end of my comment @3 and the extension of it in my comment @5.
       
      In addition to Thomas Piketty's book "Capital and Ideology" (mentioned in my comment @5), "The Age of Sustainable Development" by Jeffrey D. Sachs (the presentation of the developed understanding that is the basis for the Sustainable Development Goals) is another comprehensive presentation of the issue (population, consumption, harm done, inequity, injustice). And there are many well investigated Social Science books presenting the ways that story-telling and story-believing combine to establish Ideological explanations for the harmful inequity of the system the stories are made-up to justify.
       
      The required helpful pursuit is Developing Sustainable Improvements for Humanity through expanded awareness and improved understanding to limit harm being done. Any other activity is irrelevant, and potentially harmful.
       
      The current reality is very unsustainable. And it was harmfully over-developed in ways contrary to developed understanding of the correct direction for development.  Major corrections of the developed current day reality, especially corrections of the developed systems and the stories made-up to excuse their inequity, injustices and harmfulness, will be required.
       
      And the correction of the current day reality will require many of the more fortunate people to give up many of their developed perceptions of Superior Standard of Living relative to Others. It is likely impossible to maintain the developed enjoyments of the higher consuming higher impacting portion of the current day population.
       
      I agree that there will be many who will not willingly reduce their consumption or impacts, will not wish to pursue setting the example of Sustainable Development and Sustainable Corrections. What is undeniable is that the solution will require those people who will not responsibly self-govern and self-correct to be externally governed and corrected. That is ultimately what humanity requires in order to have an Improving Lasting Future.
7235. nigelj at 10:28 AM on 28 June 2020
      2020 SkS Weekly Climate Change & Global Warming News Roundup #25
      

      Slarty Bartfast@30

      Slarty says "The only mistakes I made were these... " (he lists two mistakes and tries to make excuses for them.)

      But hes made plenty of other mistakes. Here are just a couple of others:

      Slarty @11, "By the way, thanks for pointing out the error in the thermal expansion coefficient. I used the wrong one by mistake"

      Slarty @12 "But this doesn't change my overall point, that sea level rise is miniscule and unmeasurable" This is clearly an error, no matter what way you look at it, as pointed out several times eg me @14.

      Slarty @12 "What I did say about the Arctic is that we don't know what the temperature trend is because there are no long term weather stations within 1000 km of the North Pole, and there never have been."... "You need 50 years to establish a climate trend"

      I pointed out @16 we have at least 60 years of data over the open arctic. And I would add saying you need 50 years of climate data is only Slartys opinion. Every source I've read says 30 years is sufficient, for example the experts on realclimate.org.

      Slartys website blog claimed that climate change is caused by waste heat and quoted New Zealand as evidence where population density and industrial output is low and our glaciers haven't shrunk very much. I pointed out research @22 showing our glaciers have shrunk a great deal at 33% since the 1970s. Anyway there will be some difference between hemispheres because the northern hemisphere is warming faster due to a preponderance of land mass.

      Own you mistakes Slarty. I suspect you have a pre determined conclusion, and when you work like that you tend to twist things to suit the conclusion and mistakes multiply. Nothing personal: you are well educated and know more statistics than me, but I have a razor sharp ability to recognise nonsense in almost any field of study.

7236. nigelj at 07:54 AM on 28 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      walschuler @13

      I used to work in building design, and I agree you can get some big energy efficiencies especially if you go full passive solar. The problem is persuading people to bear the initial capital costs when they often have other objectives. For this reason mitigating the climate problem and other environmental problems requires constantly promoting a wide range of solutions, including energy efficiency, wasting less, having fewer children etcetera. Theres no magic bullet once you face the realities of human nature.

      I suspect there is little difference long term between nuclear power and renewables, in terms of clean energy and ultimate costs, but nuclear power is not politically popular and the new smaller modular reactors are very expensive, and this could take a fair while to change, so renewables are proving more popular with generating companies and the public.

      Getting the size of population down is an obvious good solution, but it probably wont happen quickly because of the risk of too many older dependent people as you mentioned. But that said, its interesting that in a couple of countries in Europe where population size has fallen and there are fewer young people and a bulge of dependent elderly,  governments have tried to incentivise people to have more children, but this hasn't worked! Once the culture swings towards smaller families it seems to get quite popular.

7237. nigelj at 07:26 AM on 28 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      It's important to cut per capita consumption, but trying to mitigate the impacts of 10 billion people even at lower levels of consumption will be a nightmare, so its equally important to cut the size of global population. Various studies suggest 2 - 5 billion is optimal. There are downsides to smaller population but not huge ones.

      This has long been realised, for example in the limits to growth report published in 1972. You can use the associated world 3 interactive model as below. Just click on simulate.

      insightmaker.com/insight/1954/The-World3-Model-A-Detailed-World-Forecaster

      You wont get perfect sustainability because nothing lasts forever, including this solar system. You can only aim to improve sustainability and I do believe we can do a much better job than currently.

7238. walschuler at 06:44 AM on 28 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      Several comments. First the Kaya equation related to the carbon problem looks in form just like the famous Drake equation for the number of radio civilizations in the galaxy. Like the latter it clearly states relevant factors making it easy to see and talk about what counts.

      Second, the discussion here and in many other places under values energy conservation. I spent a decade back in the 70s and 80s running an energy consulting firm that worked on both conservation and renewables for single family and multifamily dwellings, school campuses, smalland large commercial buildings and towns. In all cases conservation measures were straightforward to find and paid off quickly, often in from 1 to 5 years. In that range they had rates of return from 20% up to 100%, better than any other type of investment at comparable levels of risk. Doing them first cut the size requirements for renewables both for collection and storage to achieve a given level of load and energy share for them.

      We should be converting to renewables but doing conservation ahead of or at the same time we do that.

      The movie supports nuclear as a serious alternative. Though waste storage may be solvable either by burialor reprocessing, neither is settled and the problems with that plus fissionable materials diversion and weapons should rule out any continued expansion, though we might want a new safer generation of reactors to replace the old ones as they wear out. We ought to require air cooling to get their sites away from water bodies, especially near ocean coastlines.

      We do need to control population and should limit ourselves to 1 child per parent, 2 per couple. The PRC tried this and found it difficult to have enough younger working people to carry the needs of the increase in numbers elderly retired people, the latter due to improvements in their health. This can be planned for, and does not have to be instituted all at once.  However, we are not in possession of studies that clearly outline how to structure an economy with enough good jobs in a future with slowly declining population. As things are now, the US generally under produces jobs, especially good jobs. Mechanization and AI add further threats to jobs which need addressing.

7239. One Planet Only Forever at 04:33 AM on 28 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      Wol @11,

      The total population number is not the problem. The total impact of the population is the problem.

      Review the other comments, not just mine, to understand why. Each individual's action add up to become the future. Any form of resistance to accepting that understanding is part the problem.

      The unavoidable, but often attempted to be evaded, understanding is that it is harmful and unacceptable for any portion of the population to pursue personal benefits in unsustainable ways, especially if their actions are harmful to Others, and Others include all Future Generations. That leads to the clear understanding that the individuals living in ways that have higher consumption and related impacts are the portion of the population needing to correct how they live first and most significantly. It also leads to understanding that the most powerful and fortunate in the global population are required to lead the corrections, including helping the least fortunate who are the only portion of the population who can be excused for improving their ways of living with unsustainable harmful actions.

      The most fortunate need to set the example of how to live Sustainably and help the less fortunate live better with the least amount of unsustainable harmful activity as possible as they develop to live like the more fortunate. That understanding is the basis for the Kyoto Protocol. So it is not a New Idea. And the fact that it is so obvious and has been so for decades means that there are many people today in the more fortunate portion of the population who are very undeserving of their Perceptions of Superiority relative to Others (exactly the point that Black Lives Matter promoters have been exposing for decades ... about a similarly harmfully undeserving portion of the population (benefiting from harmful systemic developments, and resisting the corrections that would reduce their personal perception of Superiority relative to Others.

      What is tragic is the way that Planet of the Humans has pitted people who have a common desire to help develop sustainable improvements for Humanity against each Other, with each side in some ways defending and excusing the harmfully unacceptable developed ways of living of the more fortunate portion of the Global Population. It is as harmful and incorrect to claim that 'Renewable energy can be developed in ways that do not require any reduction of Standards of Living for the most fortunate' as it is to claim that 'Population reduction and reduced energy use will allow fossil fuel use to be sustainable'.

      The pursuit of expanded awareness and improved understanding to help achieve and improve on things like the Sustainable Development Goals is the only path to a better future for humanity. Reviewing the SDGs can show how they already include Good Guidance regarding major actions like COVID-19 response, Climate Impact response, and Social Injustice and Inequity response.

7240. Bob Loblaw at 03:34 AM on 28 June 2020
      2020 SkS Weekly Climate Change & Global Warming News Roundup #25
      

      No, Slarty, you've made lots of errors. You just don't seem to be willing or able to face them.

      I"ll just point out one more, in comment 30. You say:

      That does not change with the length of the series.

      Focus on your own words: "the series". One hundred years of temperature data (local, global, whatever) is not, I repeat not, a random sample of temperatures from a constant distribution. It is a time series.

      The statistics of a climate temperature time series are not constant over the period of the series. There is a daily cycle. There is an annual cycle. There are systematic variations due to factors such as El Nino, solar output (11 and 22-year cycles, and perhaps some longer), atmospheric aerosols, and other physical factors (CO2 amongst them) that cause variations in temperature.

      Those variations can cause changes in the mean. Those variations can cause changes in the spread (SD or other measures).

      Any collection of temperatures values that form a continuous subset of the complete record (a month, a year, a decade) represents a time series that can - no, will - have a different mean and (possibly) SD from the complete series. This is not because of random sampling difference - this is because of physics.

      Within that shorter period, adjacent measurements (two months in a row, two years in a row, etc.) will exhibit autocorrelation. They are not independent. They are not random samples.

      Everything you are doing seems to be in complete ignorance of the fact that elementary statistics of random sampling is not enough for examining time series. You can end that ignorance through learning. But first you have to accept that you still have a lot to learn.

      Here is a hint: any statistical test that you do, that will return exactly the same result if you randomly re-ordered the data (i.e. you arrange them in some order that ignores the time variable), is ignoring the time-series aspect of the data.

      You have it fixed in your mind that there is no change in the time series. That is implicit in the analysis that you do, even if you do not realize it. Concluding, on the basis of your analysis, that temperature is not changing, is not a "conclusion", it is an assumption you started with.

      You've assumed your conclusion.

7241. CD at 22:21 PM on 27 June 2020
      2020 SkS Weekly Climate Change & Global Warming News Roundup #25
      

      The only mistakes I made were these:

      @27 "You only reduce the SD by repeating the same measurement and averaging them, not by increasing the number of data points."

      Even that is not true. What I meant was, multiple measurements result in a regression to the mean. The SD will be the same for sufficiently large N irrespective of its value. For a temperature series the SD is a measure of the spread of the data about the mean. That does not change with the length of the series.

      @26 : Yes the 95% is 4-sigma not 6-sigma. Thank you all for spotting it. But that still results in fluctuations of up to 0.7 °C minimum. These are still comparable to what is being claimed by climate scientists. It is not trivial. That is the point.

7242. SirCharles at 21:37 PM on 27 June 2020
      A grand solar minimum could trigger another ice age
      

      Peter Hadfield AKA potholer54 is at it again:

      Are we headed for a Grand Solar Minimum?
      https://www.youtube.com/watch?v=wjgCaF9BGUo

7243. Eclectic at 11:09 AM on 27 June 2020
      It's only a few degrees
      

      Jasper @3 , another take :-

      In a heavily populated world, the food supply is vulnerable.   The staple food crops are rice, wheat, maize.   Plant breeding and GMO can produce some benefit in "toughening" these species against higher temperatures ~ but it is uncertain how far this can be improved [maize yield is especially damaged by prolonged hot spells].

      Even a small rise in average temperature produces a disproportionate increase in hot spells (frequency, peak, and duration).   Add to that, the increased regional occurrence of droughts and/or floods affecting crops.

      And infrastructure and poor quality soil problems will make it difficult to simply move croplands to newly-warm territory in Siberia and nothern Canada.

      Seafood is also a vulnerability, from the [CO2 caused] rising acidity in oceans affecting the shells of planktonic creatures (which provide a large part of the "base of the pyramid" supporting our fish stocks).

      Then there is the political problem of "climate refugees".   Already we have pre-existing tensions / resentments / disruptions just from the 26 million international political/economic refugees (and also from the much larger number of "internally-displaced" refugees.)

      The most recent and accurate satellite estimate of coastal elevations does indicate that a 1 meter average rise in seal level would displace approx 200 million people.  With the storm surges and salination of low-lying farmlands, the result is that many of those people will become "climate refugees" well before the average rise of 1 meter is attained.  (That may be 100 - 150 years away ~ or perhaps distinctly earlier.)

      The other big increase in climate refugees would come from the near-equatorial regions of the world, as higher/longer hot spells make "outdoor work" more difficult for part of the year.   (Would you call them climate refugees or economic refugees?)

      Many nations already have more than enough internal social problems arising from us/them types of racial or religious or cultural differences.  The addition of large numbers of "foreign" climate refugees would multiply that social disruption !

      Add to all this, some further uncertainties about climate effects on "non-staple" foodcrops & insect predation . . . and in total we have a great deal of danger facing us from even 1 more degree of warming.   (And the global warming already occurred has locked-in more sea evel rise even if temperature rise halts immediately.)

7244. Wol at 10:54 AM on 27 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      >>But the Kaya Identity illustrates why halting or even reversing that growth cannot be the answer to achieving zero emissions.<<

      Of course, put like that, it is correct.

      But total population numbers are the problem however one tries to argue otherwise. Being simplistic, zero human population = natural carbon cycle: 100Bn population = calamity even with zero carbon emissions, due to waste, environmental degradation, "rats in a cage" effect and so on. Somewhere in between is a sweet spot where, with net zero emissions, life is tolerable.

      My opinion is that population is even now well past a sustainable level for many reasons: CO2 is but one of the factors.

7245. David Kirtley at 07:08 AM on 27 June 2020
      It's only a few degrees
      

      Jasper @3, I always like to point out the difference between our climate today and the climate during the height of glacial periods in past "ice ages"...that difference is only 4-5°C. The cartoonist XKCD calls this 1 "Ice Age Unit". He has another cartoon showing Earth's history from now back to this last glacial maximum.

      A few degrees may not be a big deal weather-wise, but for climate it is a very big deal.

7246. Doug Bostrom at 06:20 AM on 27 June 2020
      Shining a spotlight on translations and our translator teams
      

      Hats off to our translators!

7247. Daniel Bailey at 05:54 AM on 27 June 2020
      It's only a few degrees
      

      Jasper, NASA took a look at that.  Part of what they found is that the crops we grow to support our civilization are evolved for a narrow range of temperatures and are currently near their thermal limit.

      NASA also more recently took a deeper-dive into that subject, with the interactive results present in 2 parts:

      Part 1

      Part 2

7248. Jasper at 03:57 AM on 27 June 2020
      It's only a few degrees
      

      I am a teacher and many students of mine say that because it is a few degrees it does not matter. The change between summer and winter is much bigger.

      I get that a few degrees make a huge difference. I don't fully understand why a few degrees matter so much. Could somebody help me with this, so I can better explain it to my students?

      Thanks a lot.

7249. michael sweet at 22:46 PM on 26 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      CBDunkerson,

      You appear to be saying that technologies must be in place before we can start to implement them.

      You listed what you apparently thought were the hardest problems to solve.  I provided solutions to them using existing technology.  Yes, if you do not count the climate, pollution and health costs than fossil fuels are cheaper than electrofuels.  So what?

      Many fossil fuels remain in place because they get so many government subsidies.  In the USA several nuclear plants have been given hundreds of millions of dollars just to stay open.  Fossil companies receive hundreds of billions of subsidies per year.  Laws to require more efficient buildings, which save consumers money, are blocked.  In Florida, where I live, it is difficult to install solar power on my roof because utilities oppose it.

      As you point out, renewable energy is the cheapest energy.  That is resulting in more renewable energy being built.  If nations support renewable energy strongly not only they start to address the climate crisis but they will save money.  Nations like Germany helped advance renewable energy when it was more expensive and showed the way. 

      Laws requiring more renewable energy will mean cheaper renewable energy will be installed faster.  Current policy in Washington to remove environmental protections and allow more wasteful fossil fuels do not help.  Currently wind and solar installations in the USA are forced to install uneconomic storage which slows implementation but makes fossil fuels more competitive.  If laws are changed to make fossil fuels pay for the damage they do than renewable energy will be installed much faster.

7250. Ben Rose at 22:43 PM on 26 June 2020
      What 'Planet of the Humans' gets wrong about renewable energy
      

      I think your analysis is somewhat simplistic. Net zero emissions means carbon emissions not above that which is being taken up by Earth's ecosystems I.e. it is about 1.5 tCO2e per per person on the planet, or about what some African nations where people don't have cars emit. In the the US and Australia, personal carbon emissions average about 11-12 t per head and total emissions 15-20 t per head, so we've a long way to go. 100% renewable electricity is a necessary start but there are many other things to be done, including as Moore says changing and reducing our consumption habits. About half of our emissions are embodied in food, housing, cars and other goods, so in addition to consuming less and differently, all these production processes have to change. For a detailed explanation of this see my website http://cleanenergymodelling.com.au/. You can do your own carbon footprint - downloadGHG-Energy Calc -and see detailed explanation by downloading the documents on at https://cleanenergymodelling.com.au/decarbonize/    (all are 10 second downloads).

Prev  137  138  139  140  141  142  143  144  145  146  147  148  149  150  151  152  Next