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The emission scenarios were developed decades ago and are proving to be over-estimates. The author interprets that as outdated science which is a rather pessimi
by perrygeo 6y ago
The emission scenarios were developed decades ago and are proving to be over-estimates. The author interprets that as outdated science which is a rather pessimistic view.
I interpret it differently: Scientists make a spread of climate predictions and their potential consequences. Those listening mustered significant market/public/government pressure and ... it worked. We pushed the outcome towards the low end of the predictions. This is good news and demonstrates the efficacy of political action based on science.
If those predictions are correct, between RCP2.6 and RCP4.5 is not a bad place to be. Climate change is still locked in but life on earth has a chance of adapting to it without major upheaval. RCP8.5 otoh, if it were to happen, we'd be screwed.
- psychiatrist24 6y agoWhat exactly was done because of pressure? More solar cells and wind mills? Have those even crossed the point where they produced more energy than what was used in their production yet? In my country, they are shutting down nuclear power plants, relying on coal instead. Electric cars are still a rarity, and global car use seems to be rising still. I find your line of reasoning maddening. While it is possible that pressure had an effect, it can be used to prove almost everything. It rained after rain dances, so rain dances work!
- adrianN 6y ago> Have those even crossed the point where they produced more energy than what was used in their production yet Yes, payback time is quite short.
- brabel 6y agoCounter anecdote: South Australia had almost 100% of its energy from coal burning just a few years ago... Today, it's nearly entirely solar-powered: https://www.abc.net.au/news/2020-10-25/all-sa-power-from-solar-for-first-time/12810366 https://www.abc.net.au/news/2020-10-25/all-sa-power-from-sol... Another one: in Norway, most cars being sold right now are electric: https://www.voanews.com/europe/norway-says-more-50-new-cars-are-electric https://www.voanews.com/europe/norway-says-more-50-new-cars-... These are huge local achievements, but it shows that at least in some parts of the world, things have changed very rapidly in the right direction.
- austhrow743 6y agoWorth pointing out with the Norwegian one as well that almost all of their electricity is renewable. So those cars aren’t just going from oil to coal but oil to renewables.
- psychiatrist24 6y agoAustralia has a lot of land and few people. Norway pays its citizens to buy electric cars with the money they make from their oil fields. So I guess the oil is still being burnt. Not saying it is not nice progress, but I am not convinced those are making a dent. Overall I think technology also progresses without government pressure or climate panic. For example batteries became cheaper because people don't want to charge their phones so often. In general people like more efficient technology and appreciate an unpolluted environment.
- bildung 6y ago> Have those even crossed the point where they produced more energy than what was used in their production yet? Yes, and they do so since the 1980s. Pardon the snark, but did you try to illustrate the article's topic?
- psychiatrist24 6y agoThe wind mills that were built in the 80ies are already scrapped, afaik they only last 20 years. How long does it take for a modern wind mill to produce as much energy as it took to produce it? Edit: a lot of estimates for 6 to 9 months seem to be floating around, but this one cites several years at least for economic break even (not exactly the same as CO2 break even, but perhaps an approximator) https://weatherguardwind.com/how-much-does-wind-turbine-cost-worth-it/ https://weatherguardwind.com/how-much-does-wind-turbine-cost... Of course, pick the estimate that suits your ideology!
- bildung 6y ago"We examine 119 wind turbines from 50 different analyses, ranging in publication date from 1977 to 2007. We extend on previous work by including additional and more recent analyses, distinguishing between important assumptions about system boundaries and methodological approaches, and viewing the EROI as function of power rating. Our survey shows an average EROI for all studies (operational and conceptual) of 25.2 (n = 114; std. dev = 22.3)." https://www.sciencedirect.com/science/article/abs/pii/S096014810900055X https://www.sciencedirect.com/science/article/abs/pii/S09601... Even a quick glance at Wikipedia would have helped: https://en.wikipedia.org/wiki/Energy_return_on_investment#Wind_turbines https://en.wikipedia.org/wiki/Energy_return_on_investment#Wi... TL;DR: Wind Mill EROI is at least about 20, i.e. they produce about 20x the energy that production and maintenance consume.
- psychiatrist24 6y agoWikipedia doesn't really prove anything, and I already mentioned that there are many claims of 6 to 9 months. Your paper seems to suggest 12 months (assuming a lifetime of 20 years).
- perrygeo 6y ago> What exactly was done because of pressure? In the past 2 decades: * Big business on the whole went from ignoring or denying climate change to embracing solutions. * Innovation in alternative energy tech and its production has driven prices for non-carbon energy down to parity with coal. * The political world has gone from ignoring it to signing on to international support for climate agreements. * People are aware of the issue and it's a central issue to billions of voters globally. * Carbon capture and other methods of reducing atmospheric carbon are being developed and scaled up significantly. > I find your line of reasoning maddening I can't prove causality but any good faith scientific argument needs to at least consider the hypothesis that the efforts of the last two decades might have had an effect. Simply ignoring the changes and saying that the original predictions were "wrong" is not a good faith argument, let alone a scientific one.
- psychiatrist24 6y agoI don't think the article was about pointing out that the original predictions were wrong. It was about the need to adjust them according to actual developments. About the other points, it is possible that politics had some effect, but I personally rather doubt it. The general assumption that businesses would just waste away energy is incorrect imo. There is always an incentive to become more efficient.
- ilaksh 6y agoBut the problem is that they are continuing to use the outdated models for current science.
- roenxi 6y agoHaving consulted a graph [0] of coal production in the UK, it seems a difficult sell to argue that there have been any policy changes in the last century. It seems likely oil will follow the same trajectory. We've been due to hit the global peak sometime soon, more oil has been consumed than discovered for a while now. If people persist in using the stuff until it runs out, it is hard to see what the effect of all the pressure was. [0] https://ourworldindata.org/death-uk-coal https://ourworldindata.org/death-uk-coal
- scatters 6y ago"Discovered" is a pretty flexible term. Geologists will only go out to look for the stuff if there's an expected return on extracting it. Similarly, "reserves" means stuff that (a) we know about and (b) that we think can be extracted economically. In effect, it's tautological to say that we'll "use the stuff until it runs out", because at whatever point we stop using it there'll still be some left that's just slightly too difficult to extract (given, hopefully, alternatives and taxes) for it to be worth it.
- sgt101 6y agoI don't understand your comment - there have been many policy interventions that have changed coal consumption in the UK in the last 100 years. There is a large amount of coal still available for mining in the uk - but lack of demand and low prices coupled with high extraction costs have destroyed the industry. - The clean air act made it illegal to burn many forms of coal and required coal producers to use higher standards. Many areas were banned from coal burning of any sort. This drove the adoption of gas central heating. - Safety measures introduced after many mining tragedies drove up the costs of the industry significantly. - The attack on organised labour in the 1980's resulted in the shuttering of large parts of the UK coal industry. - The development of the EU single market drove the importation of cheap coal from Germany and Poland, dealing a further blow to the domestic industry. - Many initiatives on home insulation driving down utilization. But you may be making a point I just haven't understood - can you clarify?
- roenxi 6y agoThey've been in a steady linear downtrend of coal production for more than a century. Then stopped producing the stuff roughly on schedule for a prediction made in 1970 or 1980. Occam's razor here is they stopped producing coal because they ran out of coal, rather than because of any political will. > There is a large amount of coal still available for mining in the uk - but lack of demand and low prices coupled with high extraction costs have destroyed the industry. That is what running out of coal looks like. Based on the 100 year trendline, Occam's razor is they can't sustain their lifestyle using coal. It wouldn't surprise me if they struggled even with new forms, their energy use figures [0] are eye watering. [0] https://en.wikipedia.org/wiki/Energy_in_the_United_Kingdom#Overview https://en.wikipedia.org/wiki/Energy_in_the_United_Kingdom#O...