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Comments 28851 to 28900:

  1. Eight things we learned from the pope's climate change encyclical

    chriskoz @79, thankyou for correcting my corrections.  Unfortunately I do have a history of messing up the arithmetic, especially on my insomnia specials (ie, posts made when I try to make productive use of my insomnia such as the one above).

  2. Renewables can't provide baseload power

    SuperPosition @151:

    "I cannot find a single grid providor who has plans to deploy grid storage which seems to indicate that, beyond specialist applications for special regions, there is no grid deployment"

    Then you haven't even tried:

    Electric Mountain

    "Water is stored at a high altitude in Marchlyn Mawr reservoir and is discharged into Llyn Peris through the turbines during times of peak electricity demand. It is pumped back from Llyn Peris to Marchlyn Mawr during off-peak times. Although it uses more electricity to pump the water up than it generates on the way down, pumping is generally done at periods of low demand, when the energy is cheaper to consume.

    The power station comprises six 300MW GEC generator/motors coupled to Francis-type reversible turbines. The generators are vertical shaft, salient pole, air cooled units each having 12 electromagnetic poles weighing 10 tonnes each, producing a terminal voltage of 18 kV, synchronous speed is 500 rpm. From standstill, a single 450-tonne generator can synchronise and achieve full load in approximately 75 seconds. With all six units synchronised and spinning-in-air (Water is dispelled by compressed air and the unit draws a small amount of power to spin the shaft at full speed), 0 MW to 1800 MW load can be achieved in approximately 16 seconds.[18] Once running, the station can provide power for up to 6 hours before running out of water."

    >170 more additional storage systems currently operational (some, but not all are experimental)

    The list is not exhaustive, not including the commerical pumped hydro facility at Wivenhoe dam near Brisbane (for example), and presumably missing others as well.

  3. SuperPosition at 16:26 PM on 24 June 2015
    Renewables can't provide baseload power

    ...moving back to what I was saying...

    Whilst it is gratifying that people seem to acknowledge to some degree or other  that the OP wording is incorrect, it is a shame that no one seems to want to change it given the given stated inention of SkS to attack incorrect or poorly applied science.

    To what standard should the reporting of fact be held on a site that prides itself in attacking misinformation?

    Many green groups have an 'RE or nothing' tenor to their agenda and I would expect that SkS and its followers would have an open mind to alternative low carbon energy (and industry) given that the intention is to effect a reduction of AGW/ACC.

    Most Green groups cite RE storage as the solution to variable RE, but I cannot find a single grid providor who has plans to deploy grid storage which seems to indicate that, beyond specialist applications for special regions, there is no grid deployment -  surely a pre-requisite to large scale RE rollout as championed by those bodies.

  4. SuperPosition at 16:05 PM on 24 June 2015
    Renewables can't provide baseload power

    PhilippeChantreau 149.

    How disappointing! This was all just a convoluted ploy to advocate for nuclear power.

    I hope that was not directed at me Phillippe - I was not the one that raised it, it was Micheal Sweet at 137.

    I do not think a list of RE compared to other energy supplies is off topic in that context. It is only data and should not have caused alarm -  I cartainly do not think I deserved the attack and negative comment.

    In any event, given that the discussion is basload power capabilities (or not) of variable RE, then the comparison with the lowest form of carbon baseload supply (nuclear) are inevitable.

    I cannot help but note the long discussion of fusion  [112 to 124]  passed entirely without thunder from above.

  5. PhilippeChantreau at 15:19 PM on 24 June 2015
    Renewables can't provide baseload power

    How disappointing! This was all just a convoluted ploy to advocate for nuclear power. That is off-topic on this thread, but I' discuss it on another more appropriate one if pointed to it.

    Being from France, I am well aware of the advantages of nuclear, for a country that has few or no other options. However, the disadvantages are becoming more and more noticeable these days, even in France. These are topics of r another thread. The wording of the OP may not be ideal but it does not contain anything disingenious and overall presents things well.

  6. One Planet Only Forever at 14:46 PM on 24 June 2015
    2015 SkS Weekly News Roundup #25B

    gregbcharles@2,

    The NOAA data is available here.

    The presentation is a little quirky. The default is set up to compare the month from any year to the same month from previous years. However, in the Timescale options the last choice "Year-to-Date" will only plot the year to date in the bar-chart but the table below the chart will show all the monthly data from the Start Year value.

  7. 2015 SkS Weekly News Roundup #25B

    While world is getting ready for Paris COP, Australia is going backwards with their renewable energy:

    Renewable energy target slashed

    The government believes the reduced target will address an oversupply of energy in the market and save consumers from possible price hikes had the larger target not been reached.

    That's the most silly explanation I've seen for so far. When something is in oversupply, the prices should actually drop, at least on a free market that I know. What kind of marketting force prompts OZ gov to conclude such  explanation that does not make any sense?

  8. Eight things we learned from the pope's climate change encyclical

    Tom@78,

    Thanks for your explanation which makes perfect qualitative sense to me.

    Your numbers do not make good sense though (careful back-envelope arithmetics may not be one your strongest skill) because you seem to sway with your energy numbers and are not sure which numbers are correct.

    I checked your numbers from last paragraph, based on the energy consumption data from wikipedia (Table of Regional energy use kWh/capita - column Year 2008, which is fine for our estimates here):

    Given 8760 hours/year:

    Per capita:

    USA - 87,216kWh, or 87,216/8760 = almost 10kW

    World - 21,283kWh or 21,283/8760 = 2.43kW

    So, current world per capita power is ~1/5 of US power

    Total:

    USA - 10kW * 300mln = 3TW

    World - 2.43kW * 7bilion = 17TW

    If you want to give world per capita power the same as US you get:

    17TW * 5 = 85TW

    Then if you want to increase population from 7 to 10bln you get:

    85TW*10/7 = 120TW

    which is exactly 1/5 of your number 600TW

    So, your original estimate "600 TW as sufficient for 10 billion at 5 times current US per capita energy usage" was spot on and you made a mistake by "correcting" it.

    Now, for the radiative forcing of those numbers, if current world total energy of 17TW yields 0.028 W/m2 (from Flanner (2009) I quoted above), then, your number of 10bln of 5 times US affluence 600TW yields 0.028*600/17 = 1W/m2 which is close to your original number (your "corrected" number 0.06 W/m^2 is way too low).

    I agree that such scenario (although unrealistic) results in signifficant forcing. The more realistic (frankly quite likely if we do not stop FF burning) scenario - 10bln reaching current US affluence would be 0.2W/m2 which is within the range of solar variations.

  9. It's too hard

    I dont think Guy McPherson has much scientific support for his claims. The consensus position in WG2 of the IPCC reports certainly doesnt support that.

    I also find it odd that someone should think that because we are in a deep hole, it makes sense to dig even deeper. Any scientific assessment of what the effects of climate change has error bars, and maybe things will pan out at the top end of that error bar if we are very unlucky. However, continued emissions is guaranteeing that things will be worse than if we stopped now.

  10. anticorncob6 at 12:26 PM on 24 June 2015
    It's too hard

    What about a subset of the "It's too hard" people who are saying that it is too late? According to them, even if all emissions ended today, we have already pumped so much heat into the atmosphere that catastrophic climate change will still happen. Therefore we shouldn't even bother with trying to fix global warming, and all we should do now is simply live the best we can until the end. I know Guy McPherson thnks this way.

    Is there accuracy to this claim?

  11. Daniel Bailey at 09:52 AM on 24 June 2015
    CO2 measurements are suspect

    "I understand that stomatal index data has certain problems, but then so does ice core data"

    Feel free to delineate what you feel those limitations might be and cite your sources.  The ice core data are among the best we have for the past 800,000 or so years for atmospheric gases.  You're going to have to do better than just an argument from incredulity.

    "some Holocene studies seem pretty robust"

    "seem" is hardly an objective assessment.

    "Surely any issues with the stomatal data could be taken into account"

    Surely.  But still an argument from incredulity.  This venue deals in evidence.  Since you seem bent on making an assertion about ice core CO2 data, the burden of proof is on you, the claimant, to mount an evidence-based claim and to support it with links to the primary literature.

    "Stomata studies showing high levels of CO2 in the relatively recent past are being used to suggest that current levels are not unusual in human history"

    Citation, please.

    "what about studies suggesting higher CO2 at the end of the Younger Dryas"

    Nebulous assertion; citation please.

    "I can't find reconstructions of CO2 levels over the last several thousand years that use anything other than ice core data, although reconstructions over millions of years use stomata and ocean sediment for the earliest periods"

    Off the top of my head, Ziegler et al 2013 does just that.  Further, it covers the period of the past 360,000 years.

    "how do we know ice core data for CO2 levels is more reliable"

    How do you know that ice core data is less reliable than stomata data?

    "aren't stomata indices useful proxies"

    Yep.  When used with proper contexts.  Which is how they are used.

    "Are there other proxies which could be used to back up ice core CO2 results"

    There are.  I gave you a link to them in my previous commentHere it is, again.

  12. New study links global warming to Hurricane Sandy and other extreme weather events

    I live in New Zealand, and we have just had one of our worst flooding events in recorded history. I suppose as a small island nation, and given higher atmospheric moisture, we are particularly at higher risk of more intense floods or possibly more floods. Any experts have any thoughts on our levels of risk, and the most likely scenario? 

  13. CO2 measurements are suspect

    APT - It is easier to have a discussion when you properly cite the papers you are referring to. I assume it is this.

    My understanding is that problems with stomata are much larger than with ice core and only used when ice core is unavailable. You might like to read the published comment on your reference before being so sure of the superiority of the stomata record.

    There are two further points of note:

    1/ the record of high CO2 at time of Younger Dryas is being presented to support that rapidly rising CO2 levels cause climate change.

    2/ The isotope signatures of CO2 at YD indicate different CO2 source to what is present today.

  14. SuperPosition at 08:24 AM on 24 June 2015
    Renewables can't provide baseload power

    [RH] You're being disingenuous as to your predilection for nuclear over other forms of RE. SkS is not the proper site to have an endless discussion that accomplishes nothing. Michael Sweet has made a reasonable suggestion that you write up your own article and submit it to the SkS author's group for review. It's a process all SkS articles go through. If it's a well cited and compellingly argued piece it will likely get posted.

    Rob, if you read the thread you will see that the discussion is about RE and the subject of nuclear was raised by Michael Sweet on 137 - not by me.

    He demanded my rsponse. If [JH] had any issue with Michael Sweet raising it (or my responding to his demand) then I am unaware of it.

    In any eventuality, I struggle to see how that could be construed as me being off topic disingenuous but I am sorry that you think it is.

    Moderator Response:

    [RH] 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.

    Continuing an off topic conversation is against policy. A reasonable path forward has been suggested. Further comments will be deleted.

  15. The latest global temperature data are breaking records

    Thanks for the discussion. And nice to know that somebody thinks that 2 degrees is both attainable and not too high.

    Tom wrote: "it is convenient to communicate in round numbers"

    I would say not just convenient, but effective. And that's most of my point. If we are about to or have already hit a round-number milepost (1 degree C above pre-industrial levels), we should be making more hay about it. Do people disagree with me on that?

    No one knows what will wake up the folks that need waking up, but they need all the prodding they can get.

  16. New study links global warming to Hurricane Sandy and other extreme weather events

    Thanks for the clarifications. John's quote was particularly helpful. I still think the main article above could be edited a bit for clarity.

  17. The latest global temperature data are breaking records

    MA Rodger @63, I noticed that.  My specific claim was that WG1 of the IPCC has not explicitly established a benchmark.  WG2 (and the SPM) of necessity have done so, but discussing the difficulties in making the estimate, and uncertainties are beyond the WG2's brief.  Therefore their statement should be considered a useful benchmark but not authoratitive (IMO).   The AR4 WG2's clearest statement on the issue is on Box 19.2:

    "Box 19.2. Reference for temperature levels
    Levels of global mean temperature change are variously presented in the literature with respect to: pre-industrial temperatures in a specified year e.g., 1750 or 1850; the average temperature of the 1961-1990 period; or the average temperature within the 1990-2000 period. The best estimate for the increase above pre-industrial levels in the 1990-2000 period is 0.6°C, reflecting the best estimate for warming over the 20th century (Folland et al., 2001; Trenberth et al., 2007). Therefore, to illustrate this by way of a specific example, a 2°C increase above pre-industrial levels corresponds to a 1.4°C increase above 1990-2000 levels. Climate impact studies often assess changes in response to regional temperature change, which can differ significantly from changes in global mean temperature. In most land areas, regional warming is larger than global warming (see Christensen et al., 2007). Unless otherwise specified, this chapter refers to global mean temperature change above 1990-2000 levels, which reflects the most common metric used in the literature on key vulnerabilities. However, given the many conventions in the literature for baseline periods, the reader is advised to check carefully and to adjust baseline levels for consistency every time a number is given for impacts at some specified level of global mean temperature change."

    From the wording (ie, "reflecting the best estimate for warming over the 20th century"), the method of the estimate seems to be simply to assume that preindustrial temperatures approximately equal early twentieth century temperatures.  That may be an inaccurate perception, but no method is explicitly stated, nor paper discussing the issue cited.

    For what it is worth, using that estimate and HadCRUT4, 2014 is 0.89 C above preindustrial temperatures.

  18. SuperPosition at 06:31 AM on 24 June 2015
    Renewables can't provide baseload power

    sorry JH, point taken.

  19. SuperPosition at 06:27 AM on 24 June 2015
    Renewables can't provide baseload power

    michael sweet 145.

    It is a comparison of RE and base load supplies, one of which is nuclear - If you want the site to be a 'nuclear free' zone then why not create a page with that in mind.

    Incidentally, I was the one discussing RE and storage whereas you raised the issue of alternates.

    Moderator Response:

    [RH] You're being disingenuous as to your predilection for nuclear over other forms of RE. SkS is not the proper site to have an endless discussion that accomplishes nothing. Michael Sweet has made a reasonable suggestion that you write up your own article and submit it to the SkS author's group for review. It's a process all SkS articles go through. If it's a well cited and compellingly argued piece it will likely get posted.

  20. michael sweet at 06:21 AM on 24 June 2015
    Renewables can't provide baseload power

    Superposition:

    Your post supporting nuclear is off topic on this thread.  If you want to dsicuss nuclear wirte a post for it.  As I stated above, these discussions are invariably a waste of time.

    Moderator Response:

    [JH] Please resist the temptation to perform the role of Moderator. Thank you.

  21. SuperPosition at 06:12 AM on 24 June 2015
    Renewables can't provide baseload power

    It is common for commentors like you to come to SkS and make wild claims about how low CO2 for nuclear is, how the power will be too cheap to meter and that they have no safety issues. This generally results is a long, fuitless argument because there is little data supplied (I see no citations to support your wild claims about nuclear).

    All the more surprising that you didn't think to check the data on the IPCC or any other reputable site - I can only imagine why you would wilfully remain unknowing.

    Why would you argue with the facts at hand?

    (1) Cost

    Technology Cost range (£/MWh)
    Natural gas turbine, no CO2 capture 55 – 110
    Natural gas turbines with CO2 capture 60 – 130
    Biomass 60 – 120
    *Onshore wind 80 – 110
    New nuclear 80 - 92.50 (guaranteed from 2023)
    Coal with CO2 capture 100 – 155
    *Solar farms 125 – 180
    *Offshore wind 150 – 210
    *Tidal power 155 – 390

    *These renewable energy costs exclude the grid huge changes and unknown cost of storage that renewable solar, wind, tidal generators would require to be deployed on a large scale.

    http://en.wikipedia.org/wiki/Cost_of_electricity_by_source#United_Kingdom_.282010.29

    (2) Emissions

    2014 IPCC, Global warming potential of selected electricity sources
    Lifecycle CO₂ equivalent (including albedo effect) from selected electricity supply technologies. Arranged by decreasing median (gCO₂eq/kWh) values.
    Technology:: Median values
    Currently commercially available technologies
    Coal – PC 820
    Biomass – cofiring with coal 740
    Gas – combined cycle 490
    Biomass – dedicated 230
    Solar PV – utility scale 48
    Solar PV – rooftop 41
    Geothermal 38
    Concentrated solar power 27
    Hydropower 24
    Wind offshore 12
    Nuclear 12
    Wind onshore 11
    Pre‐commercial technologies
    CCS – Coal – PC 220
    CCS – Coal – IGCC 200
    CCS – Gas – combined cycle 170
    CCS – Coal – oxyfuel 160
    Ocean (tidal and wave) 17

    http://report.mitigation2014.org/report/ipcc_wg3_ar5_annex-iii.pdf

    (3) Safety

    Energy Source Mortality Rate (deaths/trillionkWhr)
    Coal – global average 170,000 (50% global electricity)
    Coal – China 280,000 (75% China’s electricity)
    Coal – U.S. 15,000 (44% U.S. electricity)
    Oil 36,000 (36% of energy, 8% of electricity)
    Natural Gas 4,000 (20% global electricity)
    Biofuel/Biomass 24,000 (21% global energy)
    Solar (rooftop) 440 (< 1% global electricity)
    Wind 150 (~ 1% global electricity)
    Hydro – global average 1,400 (15% global electricity)
    Nuclear – global average 90 (17% global electricity w/Chernobyl &Fukushiima)

    **The dozen or so U.S. deaths in nuclear have all been in the weapons complex or are modeled from general LNT effects. The reason the nuclear number is small is that it produces so much electricity per unit. There just are not many nuclear plants. And the two failures have been in GenII plants with old designs. All new builds must be GenIII and higher, with passive redundant safety systems, and all must be able to withstand the worst case disaster, no matter how unlikely.

    If you genuinely want to discuss the issues then fine, but if your beliefs are so fragile that you have to throw cheap accusations then you are on your own with a mirror and a box of Andrex.

    You choose.

    Moderator Response:

    [JH] Your histrionics are not welcome on this website. Please cease and desist.

    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.

  22. michael sweet at 06:06 AM on 24 June 2015
    Renewables can't provide baseload power

    SUperposition,

    Currently in the open market wind and solar are the cheapest and most efficatious methods of generating power.  They are being built at a rapid rate around the world.  As costs decrease more will be built.  Investors are unwilling to take a gamble on your choice of nuclear. There are a number of studies, including the one I cited above, that estimate the cost and feasibility of implementing wind and solar.  Your claim that these costs are uknown is simply false.  This technology exists today.  

    Nuclear would take at least 10 years to start to build out even if people changed their opinions today.  There is no way nuclear could be done quickly.  By contrast, wind and solar are cheap enough to compete without subsidy against fossil fuels with large subsidies.  No unsubsidized nuclear is proposed or has been built in the US in decades.

    You are making up problems with wind and solar that do not exist.  For example spinning reserve, speed of build out and cost of storage issues.

    SkS has a large number of threads.  Some of them are tangental to the central theme of AGW scientific facts.  For example the thread about hte Popes' work last week.  If you want a nuclear thread write it yourself.

  23. SuperPosition at 05:52 AM on 24 June 2015
    Renewables can't provide baseload power

    Tom Curtis 134.

    If you do not find any substantial errors in the summary, then your problem comes down to:

    1) Some wording in the article can be improved to avoid ambiguity; and (possibly)

    2) The wording of the "myth" needs to be restated to better reflect "pseudo-skeptic" arguments.

    The later because pseudo-skeptics do not argue that storage technology is not currently adequate to make a full renewable plus storage system capable of meeting baseload demand, but also that they will never be able to do so, either as a technical impossibility or because it will be to expensive.

    Given that the contributors to SkS are volunteers, if your points are (1) and (2), how would you word the myths and or sections of the article you consider dodgy without at the same time implying (falsely) that renewable energy could never provide baseload power.

    Well both 1 and 2 as already stated.

     

    You'll have to excuse me but I do not know what a 'pseudo-skeptic' is plus, with respect,your premise seems a little convoluted.

    In context it seem you equate querying the efficacy of RE with climate change denial. I hope not.

     

    (1) The issue addressed by SKS is climate change. Yes?

    (2) In absolute terms the solution to AGW/ACC is reducing or removing anthropogenic (human) forcing on the climate. 

     

    I wish to achieve (1) by implementing (2)

    I am guessing that you agree.

    >>

    There are a number of methods that can be deployed - therefore I hope that you agree that whilst many are applicable, the best methods are the ones that meet the criteria of efficacy and affordability  accepting that the missing of either would result in faulure.

    Simply put, that is:: speed, availability, efficiency and cost. Yes?

    One of those solutions is RE with an unknown, unplanned cost and technology component that must be available if large scale deployment is intended.

    In summary, should SKS be proscriptive over what the solutions to AGW are or should it concern itself solely with addressing the issue of AGW denial.

     

     

  24. CO2 measurements are suspect

    @Daniel Bailey
    Sorry, perhaps I didn't phrase my question clearly enough. My question was specifically about reconstructions of CO2 levels, not temperature data.
    I'm aware of the multiple proxies used for temperature reconstruction, but I can't find reconstructions of CO2 levels over the last several thousand years that use anything other than ice core data, although reconstructions over millions of years use stomata and ocean sediment for the earliest periods.
    Given that stomata-based data indicate higher levels of CO2, how do we know ice core data for CO2 levels is more reliable? Once local variability and other factors are taken into account, aren't stomata indices useful proxies? Are there other proxies which could be used to back up ice core CO2 results?

  25. michael sweet at 05:23 AM on 24 June 2015
    Renewables can't provide baseload power

    Superposition,

    Please read the Budischak citation I posted earlier.  When they studied a large power systen in the US they found that they got sufficient power with RE.  Your scenrio is just your imagination running wild.  When you do not know what you are talking about it is a waste of time for me to respond.  

  26. michael sweet at 05:20 AM on 24 June 2015
    Renewables can't provide baseload power

    Superposition,

    It is common for commentors like you to come to SkS and make wild claims about how low CO2 for nuclear is, how the power will be too cheap to meter and that they have no safety issues.  This generally results is a long, fuitless argument because there is little data supplied (I see no citations to support your wild claims about nuclear).  If someone who was informed about nuclear, you for instance, took the time to write and article for SkS; we could all review the relevant literature and than we could agree on what the data are.  

    I have invited several posters like you in the past to write such a post but none of them were willing to do the work and write it.  Perhaps all the nuclear proponents know in their hearts that nuclear will look stupid when the data is collected in one place.  Show that I am wrong and write a post so we can review all the data.  It is a waste of time to post it again in an unrelated thread where it can never be found again in the future.

    Write a post supporting nuclear and send it in.  I have written several posts in the past, it is not hard.  The volunteers at SkS will review it and, if you do a reasonable job, it will be posted.  Then we will all know what a great technology nuclear is. If you cannot be bothered to do the work, like everyone else who supports nuclear, don't bother the rest of us with your unsupported wild claims.

    This article was written by someone who supports wind and solar.  They took the time to write an article supporting their technology.  Nuclear posters do not care enough to write anything so they have no posts.

  27. SuperPosition at 05:16 AM on 24 June 2015
    Renewables can't provide baseload power

    michael sweet 137.

    Your argument is built on a list of falicities. RE energy does not have to look exactly the same as current power generation. For example, it is not required to have so much unused excess capacity all night, and it does not require spinning reserve all the time like nuclear power. You can make any idea look bad by raising enough straw men.

    I'm sorry, but I think you missed the point of what i was saying or are just looking for an argument. I'll assume the former. 

    I have no idea what sort of grid you envisage - if you are asleep at night you still need a grid that does not drop below demand.

    On a still winters night when your sollar array's have been under two feet of snow for the last week and your massive 20hrs of grid storage is long depleted the power has to come from somewhere.

    Why bother with all that infrastructure when you can build a simple base load supply, doesn't require interlinks and hugely costly (yet to be proven or deployable) storage at half the cost and at a smaller carbon footprint?

  28. SuperPosition at 05:01 AM on 24 June 2015
    Renewables can't provide baseload power

    Superposition 134, what part of this summary from the OP do you consider inaccurate:

    The claim that RE is baseload when by definition it is not - storage may be just around the corner, but is only a potential option to accomodate variable RE onto a grid. Possibly most important is the issue of cost that would quite possbibly double that of generation is ignored.

    A solution that neither we nor the developing world can afford is not an option at all. Is it.

    At present, the only RE supply that is (marginally) cheaper than (for example) nuclear is onshore wind.

    OnShore wind requires grid extensions and storage (at 85% efficiency) to make it work and even then it would also require gas backup with our current technology and quite possibly hugely costly HVDC ibnterlinks.

    The same for CSP with storage in thiose locations where it is feasible.

     

    In contrast, Nuclear is high density, has a smaller CO₂ footprint, it requires no grid changes or special consideration and the technology is available 'off the shelf' as it were; considerably faster than RE with storage.

  29. michael sweet at 04:54 AM on 24 June 2015
    Renewables can't provide baseload power

    Superposition,

    No-one builds storage now because it is not cost effective.  It is cheaper to just sell all your power onto the grid.  Who wants to build a bunch of hydro storage (like was done for nuclear in the 1970's) and than have a white elephant.  It is not necessary to have any storage with less than 40% RE supply.  Budischak, cited above, has shown that storage is not generally economic.  With the decrease in RE costs since than it is even less economic.  The facilities to supply power on the rare occasions that RE does not supply enough are already built for peak power supply.  Solar and wind can be forecast days in advance so spinning reserve is not necessary.

    Your argument is built on a list of falicities.  RE energy does not have to look exactly the same as current power generation.  For example, it is not required to have so much unused excess capacity all night, and it does not require spinning reserve all the time like nuclear power.  You can make any idea look bad by raising enough straw men.

  30. SuperPosition at 04:38 AM on 24 June 2015
    Renewables can't provide baseload power

    PhillipeChantreau @131, renewable energy in the form of wind and solar cannot provide base load power by themselves, but the OP read in context does not claim that they can (although it is guilty of ambiguous wording). However, wind and solar energy can in principle provide baseload power when coupled with energy storage such as batteries (currently pre-orderable from Tesla, see 11:50 on the video); Pumped Heat Storage (at the prototype stage and likely to be commercialized within a few years); or pumped hydro (currently commercially available but geographically limited). The OP mentions other potential storage methods.

    When this was pointed out to Superposition, he simply ignored it.

    I'm sorry but that is not a definition of a base load supply and you cite technologies which are not available to us.

    I was not ingoring the solutions you mention - quite the opposite, I was pointing out that they are not available, pursuant to which I would also point out that no grid operator has plans to deploy them.

    Storage is feasible. That does not mean that it is practical or even the best solution.

    Perhaps one day grid companies will deploy them alongside RE plants but they are not doing so now.

    The issue is that we need to address GHGs now, not in 20 years. Do you agree?

    As I quite clearly state, a variable supply can be accomodated by the addition of storage - that doesn not change the nature of the supply, only the way that it is accomodated.

    Incidentally, you cite Tesla for micro generation/arbitrage.

    Yes indeed you could class your property as a micro base load supply (assuming that you always use a fraction of what you consume) but the costs would be tremendous.

    It's an attractive idea, but if you do the maths the storage losses are quite large (for every kw/h you generate you can only recover circa 800w/h after inversion) and you would still need to produce considerably more than you use for most of the day to be available at night or else all you are doing is arbitrage between day rate and cheap rate electricity.

    ie a Tesla lithium-ion system with an initial installation cost of $400 per kwh capacity, 80% efficiency and ability to run 5,000 cycles, the average cost of stored electricity will be 15 cents per kwh.
    To get your real electricity cost, you have to add to that 15 cent battery charge whatever you’re paying for that electricity in the first place (solar or grid)

    So yes it's handy for a rural house or well exposed off grid cabin, but a meaningless environmentally damaging toxic lithium based toy to >90% of the population, urban or not.

    Even if you did have enough left over to pump back into the grid, I do not see how an operator could possibly afford to run a grid that way on the limited number of properties where it would work.

    Domestically, it would be considerably more efficient and  easier to take the huge cost of your Powerwall system (with its limited lifespan) and spend it on increasing your thermal insulation, induction hob cooking, heat pump/recovery and installing triple glazing and let your power company supply you with what you need over and above your micro-generation.

  31. michael sweet at 04:33 AM on 24 June 2015
    Renewables can't provide baseload power

    Budischak et al (2013) claim that renewables can be used for 99+% of all power in the New England area and are more cost effective than any other method of power generation.  They do not model using any hydroelectricity (they say with hydro it is too easy to use renewables) and they do not use any linkage of their grid to nearby grids to suppliment power over larger areas.  They also do not use any method of load adjusting (as is currently used to switch industrial power to night use when coal cannot be turned off) to minimize load on days when renewables are forcast to be low.

    It is undoubtable that as engineers become acquainted with the issues of renewables they will overcome many of the current perceived issues.  Perhaps those who claim, without any data, that renewables cannot be used for baseload can point out the errors in Budischak's analysis.

    If grid balancing and load shifting are used renewables become even cheaper.  I will point out that the cost of renewables has dramaticly dropped since Budischak was written and his estimates of the cost of renewables have to be revised strongly downward.

  32. 2015 SkS Weekly News Roundup #25B

    I agree with Tor B that there must be a typo there. Also, I'm having trouble finding the NOAA data being referenced. Does NOAA have something equivalent to this NASA GISS data page?

  33. The latest global temperature data are breaking records

    Tom Curtis @59.

    The obscure IPCC inference I mention @55 for the pre-industrial tempeature being 0.3ºC below the 1951-1980 average, equivalent to 0.5ºC below 1990 levels comes from AR4 SPM5 "...a 1 to 2°C increase in global mean temperature above 1990 levels (about 1.5 to 2.5°C above pre-industrial)..." which concurs with what you brand as my "guess", and happily also concurs with your own "reasonable estimate".

  34. The latest global temperature data are breaking records

    Willi,  the 2 C limit is not a cliff.  That is, the costs of reaching 2.1 C will not differ very greatly from that of reaching 2 C, or 1.9 C.  Rather, costs will gradually increase with higher values.  As a result, the 2 C target is a  fuzzy estimate, set at 2 C (rather than 1.8 or 2.15) because it is convenient to communicate in round numbers.  When uncertainty on the estimates are included, they show a similar range to the uncertainty in temperature change since the preindustrial.  That means that with low probability we may have already reached the threshold of "dangerous" climate change; or that with equally low probability we may have a 2 C leeway.  The central estimate (of about 1 C leeway ignoring warming "already in the pipeline") is, however, a reasonable estimate for policy.

    Having said that, the uncertainty is sufficient that tracking every 0.1 C difference is largely irrelevant except that each 0.1 C increase is a step in the wrong direction.  We can track those increases from temperature anomalies from the mid twentieth century (which are well known) more easilly than those from the preindustrial (which is not well known).

    Finally, I agree with Rahmstorff (and Rob Honeycutt) on the validity and achievability of the 2 C target.

  35. Renewables can't provide baseload power

    Superposition 134, what part of this summary from the OP do you consider inaccurate:

    "To sum up, there are several types of renewable energy which can provide baseload power. It will be over a decade before we can produce sufficient intermittent renewable energy to require high levels of storage, and there are several promising energy storage technologies. One study found that the UK power grid could accommodate approximately 10-20% of energy from intermittent renewable sources without a "significant issue" (Carbon Trust and DTI 2003). By the time renewable energy sources begin to displace a significant part of hydrocarbon generation, there may even be new storage technologies coming into play. The US Department of Energy has made large-scale energy storage one if its research priorities, recently awarding $24.7 million in research grants for Grid-Scale Rampable Intermittent Dispatchable Storage. And several plans have been put forth to meet 100% of global energy needs from renewable sources by 2050."

    If you do not find any substantial errors in the summary, then your problem comes down to:

    1)  Some wording in the article can be improved to avoid ambiguity; and (possibly)

    2)  The wording of the "myth" needs to be restated to better reflect "pseudo-skeptic" arguments.

    The later because pseudo-skeptics do not argue that storage technology is not currently adequate to make a full renewable plus storage system capable of meeting baseload demand, but also that they will never be able to do so, either as a technical impossibility or because it will be to expensive.

    Given that the contributors to SkS are volunteers, if your points are (1) and (2), how would you word the myths and or sections of the article you consider dodgy without at the same time implying (falsely) that renewable energy could never provide baseload power.

  36. Renewables can't provide baseload power

    PhillipeChantreau @131, renewable energy in the form of wind and solar cannot provide base load power by themselves, but the OP read in context does not claim that they can (although it is guilty of ambiguous wording).  However, wind and solar energy can in principle provide baseload power when coupled with energy storage such as batteries (currently pre-orderable from Tesla, see 11:50 on the video); Pumped Heat Storage (at the prototype stage and likely to be commercialized within a few years); or pumped hydro (currently commercially available but geographically limited).  The OP mentions other potential storage methods.

    When this was pointed out to Superposition, he simply ignored it.

    More concerning he cites as appropriate communication an article by Leo Smith that says:

    "We have the necessary ideas in place to demonstrate that renewable energy by dint of its intrinsic nature is big, and hence expensive, impracticable, and environmentally unpleasant in its use of space, that it increases problems for conventional power stations, rather than replacing them altogether, that it can't exist alone, but only in partnership, that all of the ideas that are touted to render it effective are either impossible or totally impractical ..."

    Those claims are, of course, complete nonsense.  The ideas Leo Smith considers to be "impossible or totally impractical" are currently being commercialized.  Yet Superposition apparently considers Smith's propoganda piece as a model of accurate communication; but I would take the OP here over Smith's piece for accuracy any day of the week.

  37. Rob Honeycutt at 03:28 AM on 24 June 2015
    The latest global temperature data are breaking records

    Wili...  On RealClimate, Dr Stefan Rahmstorf makes a strong case that the 2C limit is not too high and is still achievable.

    Limiting global warming to 2 °C – why Victor and Kennel are wrong

  38. SuperPosition at 03:28 AM on 24 June 2015
    Renewables can't provide baseload power

    CBDunkerson @130.

    SuperPosition, it seems like you are misreading the text.

    You object that, "I'm sorry but what the above article descibes is the definition of somwething that is variable - The fact that storage (if it existsed) or spinning reserve (which uses fuel) could 'step in' does not magically make RE base load supplies."

    My primary concern is the description of it as a myth.

    Personally I find the description out of step in a publication that strives to debunk bad science.

    Surely it is, at the very least, confusing to the reader who may conclude that the site is biased. 

     

    For instance, It would be wrong of me to claim that my car can or could fly  - unless that is, I specifically stated that for it to do so would require the addition of wings and further noted that they cost more and were not commercially available at this time and even if they were.

    I would certainly be accused of over egging the claim unless I agreed to re-phrase my claim as "it has the potential to fly." - and then explained why.

     

    Intermitaant/variable RE is not baseload and it is utterly incorrect to class that as myth.

    The fact remains that even though technology may be deployable to accomodate large scale variation on the grid generators does not mean that variable o/p sources are baseload sources or indeed that the issue is not an issue and I would also point you to my comment ref 127. 

    The issue of the unknown cost to the consumer of the correcting mechanisms, interconnects and grid changes to accomodate variable RE sources.

    It's not like nobody will notice.

  39. Eight things we learned from the pope's climate change encyclical

    chriskoz @77, the "fossil fuel waste heat" you cite includes all non-renewable resources including nuclear power.

    To a close approximation the waste heat from nuclear industries cannot be less than the waste heat from total power consumption.  Thus, if human energy consumption rises to 600 TW, waste heat will generate a forcing of at least 1.176 W/m^2 averaged over the Earth's surface.  That low value assumes 100% efficiency in energy generation, with the only waste heat being the unavoidable waste heat from end use.  Because this is a forcing on top of any excess CO2 retained in the atmosphere, over the next several thousand years it would lift global surface temperature very close to the 2 C target even if we ceased all emissions now.  On the other hand, if return emissions to preindustrial levels that would represent about half of the current anthropogenic forcing.

    With respect to the difference between fusion and fission waste heat, fission waste heat is partially compensated for by the reduction in geothermal heat by removal of radioactive ores from the natural ore bodies.  That, however, is compensated by the generation of short lived radioisotopes that mean the waste heat of the waste is greater than that of the original ore body.  Whether this balances I do not know, but the balance is likely to be small relative to the additional waste heat from inefficiencies in energy generation.  Because current fusion designs require a large energy usage to maintain the reaction, fusion reactors would likely be less energy efficient but some of the waste heat from energy used maintaining the reaction may be usable to generate power.  Consequently, if anything I would suspect fusion reactors would generate more waste heat for a given power output, but that is by no means certain.

    Finally, I made a mistake in my energy calculations above (for which I apologize).  Specifically, I described 600 TW as sufficient for 10 billion at 5 times current US per capita energy usage when it is actually 20 times.  I translated that mistake through to my estimate of nuclear waste heat.  Correcting for that, nuclear waste heat for total energy generation for 10 billion people at current US per capita levels would be about that of the current forcing of CFC11 (0.06 W/m^2).  Consequently it would not be a problem for nuclear power supply at that level, but waste heat is a limiting factor on sustainable nuclear power supply unlike the case with traditional renewable energies (solar, wind, wave etc).

  40. PhilippeChantreau at 02:30 AM on 24 June 2015
    Renewables can't provide baseload power

    Superposition's argument has some validity. This article is very much on point and does not downplay the intermittency of specific RE sources. It clearly identifies that solar and wind do not provide baseload now and are not expected to do so. However, it classifies the claim "renewables can't provide baseload power" as a myth. Unfortunately, the oversimplification imposed on any debate by the mind manipulators who inevitably hijack it has come to equate rewable with wind and solar for the general public, even though there are many other sources, some that are not affected by intermittency.

    Nonetheless, I believe that Superposition's point is that most people would come to this page in order to addess the claim that wind and solar can not provide baseload power, a claim that is, in fact, true. Perhaps the article should have an introduction emphasizing that "renewable" does not mean exclusively wind and solar.

    Personally, I think that the potential for geothermal is immense and has been barely tapped at all. Considering the treasures of ingeniosity that have gone into drilling for oil and gas, I believe that we have quite a margin of improvement for tapping into heat that's there, completely free and with little to no side effects.

  41. The latest global temperature data are breaking records

    So let me get this straight:

    Not only is the 2 degree target almost surely set way too high;

    Not only is the 2 degree target almost surely unattainable now;

    But we also will not even be able to tell when we hit or exceed the 2 degree target, nor accurately track our 'progress' toward that dreaded goal?

    Wow, I knew we were pretty totally lost, but I didn't realize how lost we were in even determinging how lost we are.

    So all the people deciding to set a goal of two degrees have not come around to agree on one standard to measure our progress toward that limit? That just seems at ones unbelievable and all too typical. Yes there are difficuluties, but you pick one measure and stick with it unless it is found to be woefully inadequate, it seems to me.

    In any case, by all of the three measure that Tom has so kindly provided, we seem to have passed the one degree mark now.

    I know this is just an arbitrary place on the number line, but to most of us this looks like a pretty significant milestone, much lie the 400ppm mark, not to be wasted in minutiae of figuring what proxy is used for historical temperatures.

    We need as many wake up calls as we can possibly get at this point, and it just seems to me that the climate communications community is squandering an important opportunity here.

    Am I crazy?

    OK, I know, yes, I'm crazy, and histrionic as well, apparently '-).

    But is this idea wacko for some reason that I'm not seeing?

  42. Daniel Bailey at 01:30 AM on 24 June 2015
    CO2 measurements are suspect

    "Can somebody please explain why only ice core data is used for the pre-instrumental measurement period"

    It's not.  Temperature measurements began in 1659. Stations were added throughout the centuries since then, becoming a truly global network beginning in 1880. Multiple proxy records extend that record literally millions of years into the past.

    http://www.ncdc.noaa.gov/paleo/globalwarming/instrumental.html
    http://www.ncdc.noaa.gov/oa/climate/research/1998/anomalies/anomalies.html
    http://www.ncdc.noaa.gov/ghcnm/v3.php
    http://www.ncdc.noaa.gov/data-access/paleoclimatology-data/datasets
    http://www.realclimate.org/index.php/data-sources/
    http://en.wikipedia.org/wiki/Instrumental_temperature_record

    Multiproxy reconstructions are now commonplace.  For example, per the PAGES 2000 reconstruction, current global surface temperatures are hotter than at ANY time in the past 1,400 years, and that while the Medieval Warm Period and Little Ice Age are clearly visible events in their reconstruction, they were not globally synchronized events.

    http://www.skepticalscience.com/pages2k-confirms-hockey-stick.html

    From the peak temps and CO2 at the height of the Holocene Climatic Optimum some 7,000 years ago, temps and CO2 went into a long, slow decline, until about 100 years ago. Global temperatures dropped about 0.8 degrees C.

    Over the past 100 years we have entirely erased that 5,000+ years of natural cooling (Marcott et al 2013), with global temperatures rising a full degree C:
    http://www.realclimate.org/images//Marcott.png
    http://climatedesk.org/wp-content/uploads/2013/03/marcott-B-1000.jpg
    http://www.realclimate.org/index.php/archives/2013/09/paleoclimate-the-end-of-the-holocene/
    http://www.sciencemag.org/content/339/6124/1198

    Given that orbital forcing is still negative, and will continue to be negative for the next several thousand years, natural forcings are not responsible for this current warming period.

    Please place relevant comments and questions on the pertinent thread.

  43. New study links global warming to Hurricane Sandy and other extreme weather events

    @willi #1:

    I believe the answer to your question is contained in an article by Chris Mooney about the same Trenberth et al paper that is summarized by John Abraham in the OP.

    Here are the relevant sections from Mooney's paper:

    More particularly, Trenberth and his team are arguing, while changes in atmospheric dynamics are very hard to blame on climate change at the present time, thermodynamic changes involving heat and moisture are relatively easy to attribute — the world’s air and oceans are, after all, warmer. So to understand what they’re arguing in the new paper, you first have to understand this distinction that is fundamental to atmospheric science — between dynamics and thermodynamics.

    Dynamics governs the large scale motions of the atmosphere — the way in which the fluid flow of air molecules on a rotating planet leads to major patterns, such as gigantic cyclonic storms or the jet stream. In effect, dynamics governs the arrival of a given weather event in a given place, at a given time.

    Thermodynamics, in contrast, involves how temperature and moisture shape atmospheric events. Here, hotter temperatures can lead to more evaporation of water — and are also directly related to the ability for more retention of water vapor, or humidity, in the air. (“The water-holding capacity of the atmosphere goes up exponentially at a rate of about 7% per degree Celsius,” noted Trenberth and his colleagues.) Meanwhile, hotter ocean temperatures can also have a variety of effects, such as strengthening storms like hurricanes.

    Study sees a ‘new normal’ for how climate change is affecting weather extremes by Chris Mooney, Energy & Environment, Washington Post, June 22, 2015

  44. One Planet Only Forever at 00:29 AM on 24 June 2015
    New study links global warming to Hurricane Sandy and other extreme weather events

    wili,

    I believe the answer is provided in the following statements near the end of the article.

    "This new study reconciles past conflicting studies where very little evidence of a climate link was found of general circulation changes, but evidence is clear in the thermodynamics."

    "In summary, human warming affects weather in two ways. It changes the odds that any given extreme event will occur. But more importantly it makes the events more severe".

  45. Renewables can't provide baseload power

    SuperPosition, it seems like you are misreading the text.

    You object that, "I'm sorry but what the above article descibes is the definition of somwething that is variable - The fact that storage (if it existsed) or spinning reserve (which uses fuel) could 'step in' does not magically make RE base load supplies."

    All true, but irrelevant. The article does not say that these types of RE (e.g. wind and solar) can supply base load electricity. The problem is that you are assuming the words, "this is simply untrue" refer to "some types of renewable energy do not provide baseload power". They clearly do not. That phrase is preceded by the word "because"... an explicit acknowledgement that these types of RE do not provide baseload power.

    Rather, what the text is saying is untrue is the next clause, "they require an equivalent amount of backup power provided by fossil fuel plants".

    Yes, solar&wind are variable and do not provide baseload power. No, that doesn't mean that an equal amount of fossil fuel power needs to be on standby at all times.

  46. CO2 measurements are suspect

    Hello,

    Can somebody please explain why only ice core data is used for the pre-instrumental measurement period? I understand that stomatal index data has certain problems, but then so does ice core data. Fossilized stomata data is used for the more distant past, and some Holocene studies seem pretty robust and use multiple locations, e.g. Steinthorsdottir et al. (2013).
    Surely any issues with the stomatal data could be taken into account and it could be combined with ice core data to make a more accurate reconstruction of past CO2 levels. Is there simply not enough of it?
    Stomata studies showing high levels of CO2 in the relatively recent past are being used to suggest that current levels are not unusual in human history, even though this contradicts ice core data. I understand the obvious problems with the Beck (2007) work for example, but what about studies suggesting higher CO2 at the end of the Younger Dryas?

  47. Eight things we learned from the pope's climate change encyclical


    Tom@74

    Supply of energy by nuclear technologies (fission or fusion) is less efficient because waste heat becomes a relevant climate forcing at that level of production, limiting the sustainable energy supply for a 10 billion population...

    How much "relevant" climate forcing is nuke waste heat? Can you be more specific and tell us the actual numbers backed by relevant references? I think fusion WH would be somewhat different (much smaller) than fission WH because background radiation be smaller.

    We know that FF waste heat (defined as all energy from FF burning converted to equivalent heat) is 100 times less that the anthropo change in greenhouse effect and still 10 times less than e.g. solar variations, so indeed irrelevant.

  48. SuperPosition at 20:54 PM on 23 June 2015
    Renewables can't provide baseload power

    Thank you for your reply.

    I'm afraid that I must disagree - 

    Whilst I am not a electrical systems engineer, I have worked as a scienctific consultant and in particular, a Green energy consultant for the UK DCMS (gov media) and the London 2012 Olympics.

    Not once did I ever see or hear of a manufacturer or developer of the types of RE we are talking about discuss them in terms other than of none base load, variable output.

    The Industry does not regard them as BL, nor does the national grid operators of any country that I am aware of.

     This is a wholly unnecesary contradiction that may turn people away from your site and perhaps even your cause, simply because your definition and characterisation of variable o/p as 'myth' contradicts far too many accepted sources including Grid Operators, ETSO, IPCC, SDSN, DDPP and even GreenPeace for it to be credulous. 

     

    Yes I think most if not all would agree that variability/intermittancy can potentially be corrected for either by demand side management, spinning reserve or storage the fact is that those are external mechanisms which, with the sole exception of [inefficient] spinning reserve, we do not have yet.

     This point is made by Leo Smith MA [Limitations of Renewable Energy] and it is not untrue as is claimed elsewhere on SKS.

    As with addressing AGW denial, it requires a nuanced technical rebuttal of the bits that are wrong, not a dismissive gainsay or attack on the author.

    Afterall, you are not writing for people who accept AGW/ACC, you seek, do you not, to convince undecided or lay individual with fact based knowledge and logic and if a simple wiki search of the term is at odds with you then that should be addressed.

    I suggest that you accept that variability is NOT a myth, but explian that technical (and regional) solutions exists that may, over time, help mitigate/address the issue and can compensate for the variability and that these solutions need investment tio the point where it becomes irrelevent. 

    Alternately and with the greatest of respect for SKS motives, I suggest that it reference DDPP (par exemplar) and then remove all mention of Green energy alternatives to concentrate on the climate science only.

  49. The latest global temperature data are breaking records

    wili @58, while the IPCC expresses targets in terms of degrees C above the preindustrial temperatures, it reports temperatures as anomalies with respect to various multidecade periods in the 20th century (depending on which temperaure record they are using).  There is a very good reason for that.  Nobody really knows what the temperature was in 1750, although we can make a reasonable guess.

    MA Rodger @55 makes a guess based on the BEST 1750 land only temperature, but BEST land only in 1750 amounts to a few European thermometers only, and is a poor index of global temperatures.  Consequently the errors on that temperature determination are approximately as large as the difference between 1750 and 2000 temperatures in that index.  Treating the land only temperature as a global (land and sea) index would only increase that error.  This just illustrates that there were simply not enough temperature records kept in the 18th century to reasonably estimate the temperature difference between preindustrial temperatures and modern temperatures.

    An alternative approach is to use "natural thermometers" in the form of paleotemperature reconstructions.  Of this, probably the best current global reconstruction in Mann 08 (EIV).  That is expressed in terms of temperature anomalies indexed to the HadCRUT3 temperature series.  Because of the method used to correlate reconstructed temperatures with the instrumental record, and because of the slight differences between different instrumental records, using a different instrumental record will result in a different estimate of 1750 temperatures relative to modern temperatures.  This is true even if the records use the same base period.  The difference will approximately scale with the difference in the trend over the calibration period (1850-1995), but an exact determination would require replicating the reconstruction with the different temperature index.  Unfortunately, the NCDC and GISS temperature indices do not extend back past 1880 and so cannot be used in such a replication.  

    The upshot is that even using reconstructed preindustrial temperatures, we cannot determine the difference modern temperatures in general, and preindustrial temperatures.  The most we can do is determine an temperature index specific comparison which can give a rough idea, but no precise values.  And that is restricting ourselves to a particular set of paleo data for the reconstruction, and a particular methodology.

    Given these difficulties, it is unsurprising that nobody has in fact made a determination of the difference between preindustrial and modern temperatures in precise enough a manner that the IPCC WG1 considers worth citing.  Given that the role of SkS is to communicate the science, that means SkS should not give specific values for the difference no matter how convenient it would be to have them.  To do so would be to go beyond the science. 

    Having said that, it is possible to make educated guesses as to what the difference is.  Based on Mann 08 EIV, my best guess as to the difference between the 1741-1760 average and 2014 is, for three different temperature indices:

    HadCRUT4: 1.01 C
    NOAA:      1.06C
    GISS:      1.04 C

    The error for HadCRUT4 is on the order of 0.4 C, and due to the inability to determine an approximate calibration for NOAA and GISS, is likely over 0.5 C for GISS (although I have not calculated it explicitly).  So, a 1 C temperature difference is a reasonable estimate, but the error is too large for differences of +/- 0.1 C to be meaningful in the estimate.

     

    Addendum:  I should note that the SkS team are volunteers, with none of them being paid for their contributions.  In addition to the problem of not having an accurately determined scientific value for the figure you want reported, it should be recognized that volunteers have limited time.  I, for one, am thankful for the amazing resource the volunteers have managed to provide.  While constructive criticism and requests to improve articles are always appropriate, they should be made in the recognition that any response is in the nature of a favour, not something that can be demanded as a right.  

  50. The latest global temperature data are breaking records

    One last gasp...

    Look good and wonderful people.

    We need to have the whole world...the entire freaking world...riveted, glued, fixed fast to...just two or three numbers:

    1) The concentration of CO2 in the atmosphere (just passing 400ppm)

    2) The resulting global average temperature, which has generally and most publically been expressed in terms of degrees C above pre-industrial levels, as expressed in IPCC, major international agreements, books like "6 degrees," etc., etc...

    If a major new finding came out about CO2 concentrations and people decided to express it in, I don't know, drams per stone or something rather than in parts per million like everyone else, wouldn't you expect, from the writers trying to publicize such finding, that they would at the very mininmally least somewhere translate their peculiar (to most) measure into the much more widely used one??

    Please tell me what I'm missing, here, if I'm missing something glaringly obvious (it wouldn't be the first time).

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