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Comments 102651 to 102700:

  1. Renewable Baseload Energy
    Peter Lang - I'm still running the numbers from the critiques, I'll comment when I have a better feel for them. As to site placement, unless there is large scale (national) oversight, I suspect that the individual power companies will not chose the best mix of sites, but rather load sites to the highest wind levels regardless of large scale correlation.
  2. Renewable Baseload Energy
    KR, You say "But even if the costs are off by a factor of two, even if the energy requirements are off by a factor of two." You clearly did not read the critique or else you did not understand it.
  3. Renewable Baseload Energy
    KR, If you are not prepared to look at the links that have been suggested to you, then there is little point in the discussion. The points you are making have been covvered manny many times elsewhere. None of it is new.
  4. Renewable Baseload Energy
    Peter Lang - Looking at Quokka's links, the proposal discussed includes 60% concentrating solar and 40% wind. This is already reducing correlation considerably. I'll also note that this proposal (I'm sure it's optimistic, no worries about that) estimates that when global concentrating solar (CSP) reaches 8-9GW the costs will drop below coal energy costs. This proposal alone has 42GW of CSP. The timeline critiques are quite reasonable - I cannot see action occurring on that schedule. But even if the costs are off by a factor of two, even if the energy requirements are off by a factor of two - this is one potential approach to reducing CO2 consumption.
  5. A basic overview of Antarctic ice
    Hi all, OK, so I have been to the NSIDC FTP site and downloaded some data for sea ice area over the Arctic and Antarctic for January and February (peak of Austral summer) and July through September (Boreal summer) for all years between 1979 and 2010. Daniel and Tamino have also looked at this, but since HR wants us all to be critical ;) Great post Daniel by the way. Some things to note off the bat-- nobody is dismissing the presence of Antarctic sea ice during the austral summer. What I think people have been unsuccessfully trying to communicate to the "skeptics"/contrarians here is the significance of the difference in the rate of change in the sea ice extent. The distribution of land mass is also important, but more about that later. Some numbers: In the Arctic in August and September the rate of loss has accelerated in recent years-- in fact, a quadratic fit provides a much superior fit to the data for July and August and September. But for ease of comparison I will refer only to trends derived using an OLS model. Here statistically significant is set at 95% (p-value < 0.05). Arctic sea ice area trends 1979-2010: January: about -37 000 km/decade (not statistically significant) February: about -34 000 km/decade (not statistically significant) July: about -330 000 km/decade (statistically significant, p-value = 0.000) August: about -390 000 km/decade (statistically significant, p-val =0.000) September: -429 000 km km/decade (statistically significant, p-val =0.000) Antarctic sea ice are trends 1979-2010: January: about +74 000 km/decade (not statistically significant, p-value = 0.219) February: about +75 000 km/decade (not statistically significant, p-value = 0.132) July: about +158 000 km/decade statistically significant, p-value = 0.02) August: about +100 000 km/decade (not statistically significant, p-val =0.072) September: about +100 000 km km/decade (not statistically significant, p-val =0.117) So hopefully this clarifies the point that Robert and others have been trying in vain to make-- the statistically significant and accelerating rate of loss of sea ice during the boreal summer far exceeds the small (statistically insignificant) increase of sea ice during the austral summer. During the boreal summer, the minimum Arctic sea ice area is currently around 3.2 million km^2, compared to 4.5 million km^2 in the early eighties (down 1.3 million km^2). By comparison, the Antarctic sea area minimum during the austral summer is currently around 2 million km^2, compared to 1.8 million km^2 in the early eighties (up 0.2 million km^2 and that trend is not statistically significant). Another issue that I alluded to earlier (here, but I was clearly being too subtle) is that the Arctic ocean is essentially surrounded by a continental land mass which heats up rapidly during the summer. In contrast, the Antarctic ice sheet is thousands of metres high and surrounded by a band of very strong westerlies which essentially isolate it. That is why, for now at least, there has been little polar amplification over most of the Antarctic (not to mention the complicating factor of ozone loss). In contrast, in part because of the albedo feedback, there has been very marked polar amplification of the Arctic. The loss of sea ice from the Arctic during the boreal summer is easily offsetting any gains in the Antarctic sea ice during the austral summer. It will be interesting to see how long it takes before the Antarctic sea ice starts responding to the warming en mass, right now decreases have mostly been regional.
  6. Renewable Baseload Energy
    KR, The best wind sites are selected. All of what you are talking about is well known. The investors and the regulator want the best sites. But I suggest you take a look at the costs. You cannot deal with this in the absence of cost. That is the crunch. One problem is that many people have very little understanding of economics, costs, financing. It is impossible to have a rational discussion with people who want to talk about their beliefs and hopes but cannot ore will not consider the cost of what they advocate.
  7. Renewable Baseload Energy
    Ogemaniac, "Economically competitive vs what? Subsidized-up-the-ying-yang fossil fuels, whose free public garbage dumping rights alone are worth something on the order of a trillion dollar per year?" It is renewables that are "Subsidized-up-the-ying-yang". Try putting properly comparable figures on your assertions (per $/MWh; even better, take it a step further and provide $/MWh of energy that meets our demand for power quality). Regarding the cost of externailites, why don't you provide actual figures instead of adjectives. Read this and get a handle on the actual value of externalities: http://www.externe.info/externpr.pdf Look at the tables at the top and bottom of page 13. The point is that even when the externailities are included, renewables are still many times higher cost that fossil fuels or the other (unmentionable) baseload electricity generation technology. You should also taske into consideration what is the real cost to society of higher cost energy. Have a long hard think about that!!
  8. Renewable Baseload Energy
    Peter Lang - I would be very interested in a wind correlation study for Australia. That would prove or disprove any possibility of reliable power by splitting generation between different regions. Not knowing Australian wind patterns, might it possible that this region is covered by the same strong trade winds? The study I referred to here indicated correlations as low as 0.3 for Australian sites only 375km separation (small by the measures proposed) - if you chose sites in different wind patterns.
  9. Renewable Baseload Energy
    KR, You said: "First, what you want is negative correlation between wind sites." I agree. But that is not what happens in practice over areas of over a thousand km east west as is demonstrated in the Australian National Grid and other large grids. @ 184 I said: "This grid demonstrates high correlation of wind power output." That is, high positive correlation, the opposite of high negative correlation. I thought I was sufficently clear. Solar and wind cannot provide baseload generation at a cost that is anywhhere near viable. Furthermore, they are unlikely to ever be the case. US DOE hasd a goal for solar thermal with energy storage to be able to provide "baseload" generation by 2030. But the costs would appear to be enormous. The costs of providing 24 hour power (as long as there is not more than 1 day of overcast weather in a row and no dust storms) are reasonably estimated in Quokka's first link in post #175.
  10. A basic overview of Antarctic ice
    #70: "Bad data analysis is ..." Here are some key points about the data analysis in Velicogna: For both the Greenland and Antarctica ice sheets, we found that Radj^2 is larger when we use a quadratic fit, i.e., the data are better modeled by a linear increase in mass loss than with a constant mass loss. To verify that the improvement obtained with the quadratic model is significant we used an F-test. The F-test show that the improvement obtained with the quadratic fit is statistical significant at a very high confidence level (99%). Note that if we use the unfiltered GRACE time series instead of the smoothed one, the Radj^2 values drop by 2% and 16% for Greenland and Antarctica, respectively. This illustrates the importance of removing the seasonal variability in the trend estimates. The improvement is much larger for Antarctica than for Greenland. So it doesn't sound 'bad'. But I guess I would accept HR's nitpick: Why wasn't the quadratic function used shown in the paper? That way the 'acceleration' could be determined directly. But here is some 'hedging': The Antarctic filtered data also suggest a slight change in trend around the end of year 2006. It appears that the long term variability could be described by two linear trends, one for the period 2002–2006 and the second during 2006–2009. ... We fitted two straight continuous lines through the data, i.e., connected in the middle. We find that the Radj^2 for the two lines regression model is 0.97, the same than for the quadratic model So to answer HR in #55: It appears that breaking the data into two segments is not arbitrary, nor is it necessarily 'bad'. My key take-away: GRACE supports a flat rejection of the skeptic claim that Antarctica is gaining ice.
  11. The Inconvenient Skeptic at 15:01 PM on 1 December 2010
    Stratospheric Cooling and Tropospheric Warming
    Bob, I agree in keeping it simple for this. It would be interesting to see what would happen with the temperature profile with the model. I tinkered with the one in the link and didn't see anything that would generate a temp profile as a response. I am curious about the convection only model. Nitrogen would have to dissipate heat at the top, but I am curious as the method. Say a planet with nitrogen density comparable to Venus. What would happen there? I don't know, but I am thinking about that model. That is why I ask. Hope to see more like this one.
  12. A basic overview of Antarctic ice
    HR, yes, at least we can agree that your analysis of the V09 data is a distraction.
  13. A basic overview of Antarctic ice
    HumanityRules: Rather than trying to get to the heart of "skeptics" mental state why not try looking at the data critically. The comment you objected to wasn't directed at you specifically. Sorry that wasn't clear. As for your other comment, I've been looking at the data critically since the late 1980s. Please don't make the mistake of assuming that people have not been critical until they've embraced whatever species of "skepticism" you favor.
  14. Stratospheric Cooling and Tropospheric Warming
    Thanks John, It is a completely artificial and impossible situation. However, my objective was to make it understandable and to do that I had to keep it very simple. Also, the nitrogen is not necessary. People understand parts per million but the concept of an equivalent CO2 vapor pressure to that of 100 ppm and 1000 ppm would have made it more complicated. I read other explanations on the Internet explaining this but I could not understand any of them. It drove me crazy and then I had one of those Eureka moments when I realized what was going on. It is really not explainable without considering the absorption spectrum. I suppose for simplicity, I cannot allow convective transfer:):) Bob
  15. The Inconvenient Skeptic at 14:31 PM on 1 December 2010
    Stratospheric Cooling and Tropospheric Warming
    Nice article here. I have been looking at this issue as well recently. One thing I would argue is that the tropopause would be much less defined (or possibly not exist) in this situation. The tropopause on Earth is impacted by water vapor and in this case water vapor would not be an issue. As the density of the atmosphere dropped, less energy would be needed to cause a comparable amount of temperature increase. I really don't see how the tropopause would develop in this situation unless full saturation was reached. It is an interesting situation. Also. Curious if you have run a model with just nitrogen. The atmosphere would warm from convective transfer, but after that the model gets odd and I am still sorting through it. This is fun science. John Kehr The Inconvenient Skeptic
  16. Twice as much Canada, same warming climate
    GC - me too.
  17. Renewable Baseload Energy
    "The point of this post, that renewables can provide base load energy, is true. However, it is NOT accurate to claim that renewables can provide economically competitive base load energy" Economically competitive vs what? Subsidized-up-the-ying-yang fossil fuels, whose free public garbage dumping rights alone are worth something on the order of a trillion dollar per year?
  18. A basic overview of Antarctic ice
    #69 muon Thanks for playing. I acknowledged later my data presentation was a distraction from V09 data but I don't think it really matters because as you say it's all about trends. So please stay with V09's original data. It's not just about whether there is a downward trend it's about whether there is an acceleration in that trend. I think V09 (along with Rignot 2008a) appear on the surface to be the strongest supporting data for that outlook based on the Copenhagen Diagnosis figure. So the blip matters here. Look I have to disagree with your final paragraph. Bad data analysis is bad data analysis. There's no running away from that, no matter how inconsequential you think it is.
  19. Twice as much Canada, same warming climate
    Re: gallopingcamel (73) Let me know or send me a link. I'd be interested in hearing your ideas on those topics. Thanks! The Yooper
  20. gallopingcamel at 13:30 PM on 1 December 2010
    Twice as much Canada, same warming climate
    Daniel Bailey, Thanks for your comment. This is a great blog as it does not censor non-conformists (such as camels and BPs). I visited NOAA in Asheville; the most senior person I met was Tom Peterson. What he told me was "very enlightening" and I am still trying to digest it all, especially climate change at high latitudes such as Greenland and arctic Canada. I hope to have my ideas organized in a few weeks with the idea of posting them on "Digging in the Clay".
  21. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel, people have asked you, repeatedly, the simple and essential question "What happens to the photons from sources cooler than the target?" You have ignored those repeated questions, despite them being at the heart of the topic of this thread. Please answer my most recent version of that question: What happens to the photon named Greg?
  22. A basic overview of Antarctic ice
    #67: "nobody has even acknowledged whether they see that short-lived upturn around 2006." HR, I'll play. I see it! And I acknowledge it appears just as you describe: 'a short-lived upturn'. Unfortunately, your graph in #55 is in 'sea level equivalents (cm) anomalies', so there's some appling and oranging going on. However, this blip does not eclipse the downward trend, which is present no matter how you slice and dice these data. Trends, its all about trends. Agnostic at #43 made it quite clear that this is one complicated subject and we're trying to sum it up with one number. It's a bit like a conversation that someone might have over whether the stuff in their freezer is thawing evenly -- while their house burns down.
  23. A basic overview of Antarctic ice
    Re: Steve L (26, 28, 65) Sorry I missed your earlier questions! You are correct in that austral summer solstice is important (due to the sun being the highest above the horizon at that point), but remember that summer minimum ice extent is also important, as even low-angle sun hitting open water late in the melt season still gets absorbed, contributing to warming. As you noted, this then contributes in the Arctic to an extension of the fall melt season (the fact that melt there is now actually lasting into fall is remarkable). In fact, Arctic area and extent have declined in every month: and ice-edge latitude has moved poleward as well: The money shot for the Antarctic is this: poleward retreat of sea ice goes only so far. The continent, with its lofty elevation and citadel of cold (buttressed by the ozone-hole-strengthened circumpolar vortex) is relatively immune for now to the summer suns' direct effects. The Arctic has no such reinforcements at its back. Latitudinal retreat will continue until the pole is reached, and summer ice known to millennia of mankind will be no more. Cryosat-2 data will provide definitive data on Arctic ice mass & will be the final (until we get something better) arbiter for ice data for both poles. Per Tamino's post, Antarctic summer ice minima increase is not statistically significant. When the Southern Ocean warms enough, then we will see an early and longer melt season in the Antarctic (with trends growing similar to those I showed you for the Arctic). Which is bad news for the WAIS in general and the PIG in specific... Thanks for reminding me about Tamino's post! The Yooper
  24. A basic overview of Antarctic ice
    64 Philippe Chantreau My point hasn't got as far as the wider perspective on the subject. It's specifically about the way the data is used in Velicogna 2009. If data is used badly in making an argument there is no defense for that work in the fact that it is in agreement with other studies. I don't disagree with your general argument that there is strength in independant well crafted analysis supporting a particular interpretation. My question is whether we have that in the first place. I'm still looking for a bold defence of V09's method of data analysis given that I recognise important variablity in the data. Of the few people who've responded to my post nobody has even acknowledged whether they see that short-lived upturn around 2006. Philippe please have a go at critiquing my specific criticisms of the data, I'm happy to discuss the merits of mutaully supporting evidence after I've got over the hurdle of whether the V09 estimates are meaningful.
  25. A basic overview of Antarctic ice
    HumanityRules, Perhaps the reason Velicogna uses 2006 as a start date is because the rate of ice loss after 2006 was greater and because Rignot et al. 2008 a,b measured accelerations in glaciers for sure between 2006 and 2007. I also noticed that you have yet to address the issue that multiple methods are supporting the same answer. It is because of the aforementioned uncertainties that we should look for independent measurements in agreement. That is the crux of science. We acknowledge there is the potential for error in analyis but when we see it repeated with similar conclusions and different methods then we conclude that there is a foundation upon which claims can be built.
  26. Renewable Baseload Energy
    An Australian study (very small) on wind speed correlations: Gloor 2010 "Due consideration must be given to local conditions when assessing these correlations. Take Carnarvon and Geraldton for example. Though they are fairly distant from each other (446 km) they show a strong correlation (0.47) as they are in the same wind conditions of the Trade Winds that blow constantly and consistently over a wide area. So wind farms in Carnarvon and Geraldton would tend to go offline at the same time despite being quite well separated in distance. Contrast this with Perth Metro to Albany. Albany is in the southern ocean wind pattern, well out of the trade winds and has a lower correlation (0.33) with Perth Metro despite being only (375km) distant. So wind farms in Albany could continue to provide power to Perth when the wind farms around Perth would be at low output potentially. This is taking advantage of the different wind regimes. ... The graph of correlation with distance for these datasets does show a decreasing correlation with increasing distance however the spread of data is quite large. There is not a neat line of decreasing correlation but more a broad range. However it does support the idea that widely spread wind farms, taking into account the wind regimes of the sites, can be less correlated than closely spaced wind farms. If the correlation relationship held up then these wind farms, if connected together, could perhaps provide more reliable power than a single wind farm or group of closely grouped wind farms."
  27. Renewable Baseload Energy
    Peter Lang - First, what you want is negative correlation between wind sites. If you use sites with negative correlations, when the wind dies at one site it's high at another - say sites on opposite sides of the country. And using a mix of renewables (solar and wind) reduces correlation of down times even more. Second, you are once again focusing on a single area of Australia, the South-East. As I stated in an earlier discussion, widely separated sites are required. I don't know the details of Australian wind samples, it may not be possible to get sufficient negative correlation to supply significant baseline. On the other hand, it quite possibly may. It certainly seems possible in Europe, but again I don't have detailed multi-site wind/sun surveys with correlations in Australia. Third, with sufficient negatively correlated sites, base capacity, and storage, your argument that wind farm backups would burn more gas than straight non-stop natural gas turbines is, frankly, simply ridiculous. That requires near-constant use of the turbines with stop/start cycle energy outweighing the time off due to wind input - and with uncorrelated sites and storage, that's not going to be the case. Personally, I consider Masterresource a strongly biased and poor source (like WUWT) - I would prefer seeing calculations by someone without an axe to grind. The article you pointed out on baseline requirements is interesting - instant loads covered by generators, intermediate by gas turbines. Solar cannot cover the 'generator spin' loads, although wind can. There are certainly some points worth considering there, points directly related to renewables. I would strongly suggest (Moderators - opinions?) that any discussion of nuclear energy pros and cons remain on What should we do about climate change?, where that has been hashed out over 379 comments to date. Please do not hijack this thread.
    Moderator Response: [Daniel Bailey] Agreed. This thread is about Renewable Baseload Energy. Comments about nuclear energy are off-topic here, and should more appropriately be posted on the What-should-we-do-about-climate-change thread. Thank you all in advance.
  28. A basic overview of Antarctic ice
    Re #62 & 63, I posted comments similar to what Bill wrote here (see #26 and 38). My comments were ignored. :( DB(Yooper) -- the fact that Antarctic sea ice melts back to the continent by the end of the austral summer does not contradict the fact that there is sea ice there during the austral summer solstice. Cryosphere today says the current sea ice area there is 10.9 million sq km. There will still be millions on December 21 and even January 21. There could be as much as a half million sq km more ice than the 1979-2008 average over that time period (currently 0.3 million sq km). This anomaly in reflective area may not be as great as is observed in the Arctic during the boreal summer solstice (can someone check?), but we shouldn't pretend that it doesn't exist.
  29. Renewable Baseload Energy
    Rob Honeycutt, Have you heard of the Pareto Principle. One application is to put most of your effort into what can have the largest effect. Non hydro renewables may provide 10% of future power supply - perhaps. Nuclear and pumped hydro can provide 100% now. It has been doing nearly that for the past 30 odd years in France and providing low cost electricity as well. We have a proven way to cut emissions at low cost. Why waste any more time chasing the renewable dream. @180 last paragraph you put out the often stated argument which in effect is "I am not against nuclear, but renewables will be part of the solution so let's focus on them". This has been going on for 20 years in Australia so no one is prepared to remove the impediments to nuclear in Australia. We need to put our main effort where we can get the biggest gains. That is on nuclear. So I'd urge all those who want to cut emissions to put their efforts into changing the opinions of the anti-nukes - the environmental NGOs, media (especially ABC), and the politicians. It is far more important, and urgent, to remove the impediments to nuclear than it is to implement a carbon price. Once a carbon price is implemented then the many impediments to nuclear and favouritism for fossil fuels and renewables will be very hard to remove. We need to focus first on removing the impediments to nuclear.
  30. Renewable Baseload Energy
    Rob Honeycutt, Investor dollars are being poured into renewables because the government is mandating them and subsidising them. Wind power is subsidised by about 100% to 150% and solar by about 1000%. The investors are guaranteed the income from government and consumers for 20 years. Under such conditions of course investors will invest. The point I'd make is, people contributing on Skeptical Science think they can do objective research. But just wishing and wanting is not going to make renewables viable. They are not viable and probably never can be (at more than about 10% of the total generation). There is far too much to explain in the comments field. I'd urge those that are seriously interested to actually read the links from people in the industry, not just the renewable energy advocates. The anti nuclear protesters over the past 40 years (the same people as the renewable energy advocates), by blocking nuclear have caused CO2 emissions to be about 20% higher now than they would have been if the development of nuclear power had been allowed to progress in the Western democracies over the past 40 years. Not only are emissions 20% higher now than they could and should have been but they will remain much higher for many decades because the development process was stalled and it will take decades to recover to catch up. That is what irrational advocacy does. So, I urge you that think you can do objective research to start informing yourselves. Look beyond the spin propagated by the so called environmental NGO's like Greenpeace, WWF, FoE, and the Australian Conservation Foundation.
  31. Renewable Baseload Energy
    KR, There is another really important point to understand. The claims about how much CO2 emissions are avoided by wind farms are bogus. It seems that wind farms avoid littel if any CO2 emissions and can actually cause more emissions than if there is no wind in the system. This explains: http://www.masterresource.org/2010/06/subsidizing-co2-emissions/
  32. Renewable Baseload Energy
    KR, To see the positive correlation across the Australian NEM wind farms look at the charts for - August 2010 (seven cycles of power output from 20% to 80% of capacity), http://windfarmperformance.info/documents/analysis/monthly/aemo_wind_201008_hhour.pdf - May 2010 (Capacity factor averaged less than 5% for a week and was negative on 65 5-minute intervals during that week) http://windfarmperformance.info/documents/analysis/monthly/aemo_wind_201005_hhour.pdf To get the data: http://www.landscapeguardians.org.au/data/aemo/
  33. Philippe Chantreau at 11:36 AM on 1 December 2010
    A basic overview of Antarctic ice
    HR says: "The conclusions in the Velicogna paper should stand on their on feet irrespective of what other authors have published." That only is to be understood in terms of its internal logic and how results are supported by data used. It does not go beyond that. When considering the field of study, the conclusions of a paper should always be weighed with what else has been published before and after on the subject. Why should it not?
  34. Renewable Baseload Energy
    KR, This talk about wind power and solar power being able to provide baseload generation is just nonsense. I'd suggest you and the others pushing this advocacy of renewables should take more notice of the people in the industry than of the academics wanting renewables at any cost. The Australian NEM is the largest grid in the world in arial extent (so I understand). Wind farms are distrobuted over the southern part in an area 1200km east-west by 800 km north-south. This grid demonstrates high correlation of wind power output. In May we went for a week with almost no output from all the wind farms spread over this area - at times the output was negative by up to 4 MW - thaty is the wind farms were drawing more power that they were generating. The same is being found throughout the world. However, even if positive correlation was the case over much larger areas, the cost of the transmission systems and of the grid power and frequency control systems is enormous. In Australia, the current capital cost of wind farms is aboiut $2900/kW. Grid enhancements allow $1000/kW. Gas back up about $1000/kW. Total about $4900/kW. That is for about 30% of the energy coming from wind power. If you want say 90% coming from wind power (on average) then the cost is three times higher for the wind farms and transmission. The total cost per average kW is 3x($2900+$1000)+$1000 = $12,700/kWy/y. For comparison, nuclear would be about $4,500/kWy/y. This is based on the newly contracted price for the 5400MW nuclear power station being built in UAE by a Korean consortium; the cost is $3,800/kW with say 85% capacity factor, $3,800/85% = $4,470/kWy/y. The comparison is not even close. If we could just throw off the blinkers and stop the wishful thinking about renewable energy, the answer to cutting emissions from electricity generation is obvious. Did you read the links I provided. Have you read the the "Zero Carbon Australia - Stationary Energy Plan - Critique"? Links were provided by Quokka at 2:18 this morning. I'd urge you and others who are objective to read the critiques.
  35. Renewable Baseload Energy
    @RSVP: "As to what other posters have said, and no lack of sincerity, it is precisely the great energy associated with fossil fuels that led to the population explosion in the first place." I'm sure you can provide scientific evidence that the two are directly correlated? I'm intrigued by this idea, because the countries that have had the biggest population increases are far from being the ones with the most gas-powered vehicles per capita. I'll be waiting for that info while making sure that quokka and Peter Lang are repeating the same old arguments about why Nuclear is the *only* solution, disregarding the reality of what renewables have accomplished in just a few years while diminishing the real costs of nuclear...
  36. Renewable Baseload Energy
    As if right on cue Steven Chu spoke yesterday at the National Press Club. Dr Chu states that China is investing aggressively in renewables and expects to be drawing 20% of their electricity from renewables by 2020. Peter Sinclair posted an abbreviated version of his talk here. Or there is a full length video of his speech here.
  37. A basic overview of Antarctic ice
    Re Billhunter (62) What part of: "In Antarctica, sea ice grows quite extensively during winter but nearly completely melts away during the summer" Do you not understand? The point of the post is that focusing on Antarctic Sea Ice (ASI) is a strawman argument. ASI offers little contribution to the global energy budget, unlike changes in Arctic Sea Ice cover.
    "Even if we limit the argument to sea ice we can see that indeed it is gaining sea ice. "
    Which then melts away come Antarctic summer. The Yooper
  38. A basic overview of Antarctic ice
    Your argument is strange. When one looks at the graphs you provide a good amount of sea ice remains in the southern summer, yet your argument turns on sea ice not melting in the summer thus providing no feedback. Sea ice not melting in the southern summer is patently false and can be seen clearly in your own graphics. Now perhaps when and if the antarctic actually does melt to the edge of the continent a month or two earlier than normal your argument will carry some weight. But for the moment it doesn't seem to explain what it purports to explain is some alleged oversight in skeptic arguments that Antarctica is gaining ice. Even if we limit the argument to sea ice we can see that indeed it is gaining sea ice.
  39. Renewable Baseload Energy
    #178, #179 I don't think base load is a precisely defined quantity - it is dependent on the energy system, energy use and incentives/price structures. If, for example, nighttime power were 10 times as expensive as daytime (think PV-based supply, high CO2-taxes for fossile backup), most persons and businesses would be able to adapt to that. (People charging their electric vehicles at daytime and partly running household applications off battery at nighttime, for example.) Most heating can be buffered, and process industry could have its own supply structure, etc etc. Without rather high-resolution wind data, it is, generally, impossible to give precise estimates of the coverage of a regional wind turbine system, but if a fossile-based generation capacity is already in place, the question will just be how much this backup will be run, not whether a system can be based on renewable energy as one main component. If the main variability is on short (hours) time scales, solar thermal could have a role, biomass could be used for longer time scales.
  40. Renewable Baseload Energy
    Peter @ 177... I've not read the entire article you linked to but I would suggest that is one case against renewables for baseload. There are obviously huge investor dollars going into renewables right now, and I don't think those dollars are being put in just out of the goodness of people's hearts. They are in this because they think this will be the future of energy generation. Think about it this way: One, we have peak oil either here or coming soon. People can try to wiggle around about that idea and what it means but it's going to affect the future energy mix. Two, at some point climate change is going to become dreadfully obvious to everyone. If we price carbon early it's going be a relatively painless transition. If we put it off, we're still going to have to price carbon but it's going to have to be very aggressive and very painful. There is just no getting around it. Eventually we are going to end up with a carbon free baseload. A large part of that may be nuclear. But I would certainly bet a % of my investment dollars that a sufficient chuck of that baseload is going to be renewables as well.
  41. Solving Global Warming - Not Easy, But Not Too Hard
    Not what a lot of skeptics would expect (or want to hear): http://www.bbc.co.uk/news/science-environment-11881663 CBI (Confederation of British Industry) supportive of carbon counting and most companies say it is beneficial.
  42. A basic overview of Antarctic ice
    59 Phila I think if I made those sort of accusations about climate scientists that you make about "skeptics" my post would be deleted. I see no comspiracy and don't suffer from nihilism. What I see is data and interpretations that are put forward by Velicogna for critical analysis. That's the way normal science works. Rather than trying to get to the heart of "skeptics" mental state why not try looking at the data critically. You can make a much better defence of the data by doing that.
  43. A basic overview of Antarctic ice
    56 Albatross Albatross thanks for recognizing I tried hard with that analysis. The one thing I didn't do is insinuate anything or suggest anything nefarious. I did think about doing that but tried to stick with John's comment policy and stick to a critique of the authors results. I think we all know that a difficulty with describing rates of change from very short data sets is that variability can lead to very different trends depending on where you start and stop your analysis. I don't really know why I'm describing this to you because I know you have the skill set to appreciate this very basic point already. Please ignore my data presentation, it was only intended to illustrate my points but know I see it's just a distraction. Look at the Velicogna graph (red x's) I show in #55. Tell me around 2006 there isn't a short term slowdown and reverse in the trend. Tell me that if you start and end analysis then that this won't affect the value of your rates. Please tell me the slope of the data is signficantly different before (2003-2005) and after (2007-2009) this 2006 blip. This can all be done by just eyeballing Velicogna's graph, remember she is suggesting rates of ice mass loss have more than doubled over this time period. Do you see that? The conclusions in the Velicogna paper should stand on their on feet irrespective of what other authors have published, I'm really happy to look at the quality of those other results but I relly think if you are going to defend what Velicogna writes then do it based on the merits of her methods not on what others have done. Look I would turn your own comment back onto you in relation to looking at the quality of Velicogna's interpretation of this data. "Really, the lengths some people will go to to convince themselves that there is not a problem."
  44. Renewable Baseload Energy
    Peter Lang - You might want to look at the link Alexandre posted, noting low and even negative correlation between power available when generating stations are widely enough separated. This includes a fairly detailed case study for Europe. It's worth noting that the correlation between windmills separated by as few as couple hundred meters show extremely low values over the <1 minute scale, and proper site selection around Europe shows negative correlation sufficient to handle even seasonal irregularities without a dropout - thus supplying baseline power. I don't know if the same analysis would apply to Australia (due to area and local variations - that would take a sufficiently detailed wind/solar survey), but it would be interesting to look into. You had complained about intermittent power at a particular wind farm - but sufficiently separated wind farms mixed with sufficiently separated solar farms might be quite capable of complete baseline power for Australia too. Yes, long distance DC lines and power storage are important requirements for renewables. But if we have sufficient power and low correlation between sites, your concerns about huge natural gas burners for backup essentially go away. Power storage for short term variations is required for coal and nuclear too - they simply don't ramp up/down fast enough for those variations. If you wish to go on about nuclear (as opposed to the renewables discussed here), I would suggest directing people to the threads where that conversation has already taken place - no need to repeat it here.
  45. Renewable Baseload Energy
    I think it is important to differentiate between investment and operating costs. With sufficiently high calculation interest rate, any sustainable project can be made "too expensive", and with sufficiently low rate, a lot of impractical projects may become "profitable". Because this rate is so essential to all calculations, I tend to distrust purely theoretical analyses. To me, it is much more important what kind of track record the different systems have. So far, it seems to me that renewable technologies are more expensive to implement, but I don't know if the operating costs always have to be that high. I think we need quite a lot of operation data for full-scale systems to make safe judgments. Experience from Scandinavia, where Denmark has a very high coverage of wind power, Sweden has started utilizing biomass for energy production on a large scale (in an ecologically rather safe manner), and Norway traditionally has ca 50% coverage of _total_ energy consumption from hydroelectric power, indicates that sustainability doesn't necessarily come at extremely high costs.
  46. Renewable Baseload Energy
    I've only just spotted this thread and haven't been following it. Others may have already posted this link to "The Case for Baseload": http://www.eei.org/magazine/EEI%20Electric%20Perspectives%20Article%20Listing/2010-09-01-BASELOAD.pdf This explains why the concept of baseload is rock solid and intermittent renewables cannot meet the requirements. Baseload comprises over 75% of our electricity demand and generation in Australia. It cannot be ignored. David Mills, Mark Diesnedorf, Mark Jacobson and many other renewable energy advocates have been arguing for over 20 years that solar and wind power can meet our needs for reliable power. It is just not true. This is also an excellent article pointing out the reality of how much intermittent renewable energy generation can be accommodated in the grid. Rupert Soames Speach to Scottish Parliament, 12 November 2010: http://www.aggreko.com/media-centre/press-releases/speech-to-scottish-parliament.aspx There is reality and there is wishful thinking. We've had 40 years of anti-nuclear protesting and 30 years of renewable energy advocacy and wishful thinking. It is time for some reality.
  47. Greenland ice mass loss after the 2010 summer
    There is no fixed concept of how many data points you need for statistical significance. When you try to relate two data sets where you have reason to believe one is causally related to the other, you need to use two measures:
    • strength of the relationship, measured by correlation
    • significance of the relationship, measured by the t-test of the correlation
    If you use this calculator, you will see that a correlation of 0.9 (very strong relationship) is also highly significant (p = 0.0073) with as few as 6 data points (the smallest number the calculator accepts). You use a one-tailed test a scenario where only a positive or negative correlation is meaningful, not both. On the other hand a correlation of 0.2 with so few data points is not significant (p = 0.352), whereas the same correlation with 100 data points is (p = 0.023). It is not quite this simple: you need to worry about issues like autocorrelation, and your trust in a statistical test is higher if you have a well-tested causal model, but the basic principle is if you have a p-value < 0.05 (95% chance the effect isn't random) your confidence that you have a real effect should be high, and it consequently becomes more interesting to demonstrate why the effect is not real, rather than the converse. You also cannot apply this kind of correlation (Pearson's) to data sets with very different statistical properties, or where the two data sets have different scale intervals (e.g. one is a log scale and the other isn't and you don't expect an exponential relationship).
  48. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel - Also, you're incorrect in your statement about equilibrium temperature being unconnected to albedo. Even a simple climate model indicates about a 1°C temperature change for 3.3% change in albedo, 1.4% change in solar constant, or 1.4% in emissivity (for independent changes of a single value).
  49. 2nd law of thermodynamics contradicts greenhouse theory
    damorbel - You are incorrect when you state that IR from the Earth without GHG's (at current temperatures) would be anything but 396 W/m^2.
  50. 2nd law of thermodynamics contradicts greenhouse theory
    Emissivity of the ground is in the range of 0.96 to 0.99, with cloud albedo at 0.5 accounting for a combined emissivity (relative to a blackbody) of ~0.612. An effective emissivity change of 1.4% (from that same link, with a very simple climate model) will result in a 1°C temperature change. And greenhouse gases directly affect the emissivity of the Earth. As to your "helium atmosphere", total removal of greenhouse gases is a Gedankenexperiment. It's not intended to fully determine an end state, but rather serve as an illustration of how changing a parameter would cause a change from the current state, thus illustrating the importance of that parameter. Arguing about the endpoint of a Gedankenexperiment is quite simply a red herring.

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