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#191
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Global Warming/Climate Change (was contrails)
delboy wrote:
xt - The UK Government was very keen on carbon neutral biofuels from crops, until it was pointed out to them that the land area required would leave very little for growing food! Derek Copeland They now seem enthused about the off-shore windmills now in operation there. Some said to be many miles offshore. Brian W |
#192
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Global Warming/Climate Change (was contrails)
On Jan 10, 11:59*pm, T8 wrote:
Oh, dear...http://www.dailymail.co.uk/sciencete...DAVID-ROSE-The... A good rule of thumb with the Daily Wail is that if it says X is true then don't merely regard X as unproven, but do regard not-X as true. |
#193
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Global Warming/Climate Change (was contrails)
On Jan 10, 11:15*pm, delboy wrote:
On 10 Jan, 20:39, Tom Gardner wrote: On Jan 10, 8:24*pm, Gary Evans wrote: MacKay has interesting, simple and plainly valid "normalisation techniques", *one* of which is: * - work out the land area we each occupy (in the UK) * * i.e. area/population, which has to be sufficient for * * all our needs if we are to be self-sufficient * - for each use to which that area could be put, how * * much can we extract * - what are our current needs, and how could they be * * realistically changed Examples are energy from wind, energy from crops, energy for food, energy for cars or busses or trains or aircraft etc.- Hide quoted text - - Show quoted text - The UK Government was very keen on carbon neutral biofuels from crops, until it was pointed out to them that the land area required would leave very little for growing food! Derek Copeland MacKay is very good at pointing out such woolly thinking. Or, more accurately, at pointing out that what you gain on the swings you lose on the roundabouts. |
#194
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Global Warming/Climate Change (was contrails)
On Jan 10, 4:59*pm, T8 wrote:
Oh, dear...http://www.dailymail.co.uk/sciencete...DAVID-ROSE-The... Well, if it is the start of an ice age, those transitions tend to happen extremely fast in geologic terms. Sort of like a sudden viscous winter storm that doesn't stop for 200,000 years. In reality, the part of the story about arctic sea ice increasing 27% since 2007 is typical media rabble rousing. 2007 saw the least arctic sea ice on record so any subsequent year would likely see an increase even though the overall trend is steeply down. Seeing the Arctic ocean clear of ice in summer within the next decade is still a plausible bet. If it does happen, there will be political havoc on the right. |
#195
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Global Warming/Climate Change (was contrails)
On Jan 10, 8:41*pm, Tom Gardner wrote:
On Jan 10, 11:59*pm, T8 wrote: Oh, dear...http://www.dailymail.co.uk/sciencete...DAVID-ROSE-The... A good rule of thumb with the Daily Wail is that if it says X is true then don't merely regard X as unproven, but do regard not-X as true. :-). Yes, I added that primarily for light amusement. The gal on the right hand margin in body paint adds a little color to a drab January day, as well. Thanks again for the link to MacKay. I'm fascinated by the deftness with which he breaks these topics down into bits that any sharp highschool student can grapple with. A superb teacher. -T8 |
#196
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Global Warming/Climate Change (was contrails)
Tom Gardner wrote:
On Jan 10, 11:59 pm, T8 wrote: Oh, dear...http://www.dailymail.co.uk/sciencete...DAVID-ROSE-The... A good rule of thumb with the Daily Wail is that if it says X is true then don't merely regard X as unproven, but do regard not-X as true. And along those lines, be sure to read what the US National Snow and Ice Data Centre in Colorado, a source they reference, says regarding 2009: "Arctic sea ice extent remains low; 2009 sees third-lowest mark" "We still expect to see ice-free summers sometime in the next few decades. "Arctic sea ice extent at end of December 2009 remained below normal" "The linear rate of decline for December is now 3.3% per decade." "Despite the cool summer, the ice remained thin and vulnerable at the sea ice minimum, with little of the older, thicker ice that used to characterize much of the Arctic." "Only 19 percent of the ice cover was over 2 years old, the least in the satellite record and far below the 1981-2000 average of 52 percent." No good news there, unfortunately, despite The Mail's spin on it. -- Eric Greenwell - Washington State, USA * Change "netto" to "net" to email me directly |
#197
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Global Warming/Climate Change (was contrails)
On 10 Jan, 20:47, Tom Gardner wrote:
On Jan 10, 8:24*pm, Gary Evans wrote: Quote from the book of Gore, chapter 7, verse 3. Numbers can be our friend if we use them correctly. As MacKay says ... In a climate where people dont understand the numbers, newspapers, campaigners, companies, and politicians can get away with murder. We need simple numbers, and we need the numbers to be comprehen- sible, comparable, and memorable. With numbers in place, we will be better placed to answer questions such as these: 1) Can a country like Britain conceivably live on its own renewable en- ergy sources? 2) If everyone turns their thermostats one degree closer to the outside temperature, drives a smaller car, and switches off phone chargers when not in use, will an energy crisis be averted? 3) Should the tax on transportation fuels be signi?cantly increased? 4) Should speed-limits on roads be halved? 5) Is someone who advocates windmills over nuclear power stations an enemy of the people? 6) If climate change is a greater threat than terrorism, should govern- ments criminalize the glori?cation of travel and pass laws against advocating acts of consumption? 7) Will a switch to advanced technologies allow us to eliminate car- bon dioxide pollution without changing our lifestyle? 8) Should people be encouraged to eat more vegetarian food? 9) Is the population of the earth six times too big? Hopefully yes to question 1 and possibly question 7, and no to the rest. If AGW is shown to be a scientific myth, I trust that the UK Government will withdraw Airport Passenger Duty (tax) and other 'green' taxes. Derek Copeland |
#198
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Global Warming/Climate Change (was contrails)
On Jan 11, 4:39*pm, Eric Greenwell wrote:
"Only 19 percent of the ice cover was over 2 years old, the least in the satellite record and far below the 1981-2000 average of 52 percent." I don't know about you, but it seems clear to me that if ice was at the lowest level ever two years ago and has since staged a huge recovery, then saying that 81% of the the ice cover is less than two years old doesn't actually add any new information and certainly is not bad news. |
#199
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Global Warming/Climate Change (was contrails)
On 11 Jan, 01:37, brian whatcott wrote:
delboy wrote: xt - The UK Government was very keen on carbon neutral biofuels from crops, until it was pointed out to them that the land area required would leave very little for growing food! Derek Copeland They now seem enthused about the off-shore windmills now in operation there. * Some said to be many miles offshore. The off-shore windmills will be a hazard to navigation and shipping, and possibly sea birds. Windmills on land apparently interfere with Air Traffic Control radar, as well as making some ridges untenable for gliders and being a general eyesore (visual pollution of the environment). Every bit of high ground in otherwise beautiful Spain is covered with the goddam things. If we relied on these for electricity, we would have to turn everything off on still days, or fire up the remaining fossil fuelled power stations. Derek Copeland |
#200
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Global Warming/Climate Change (was contrails)
Read the book; it *is* worth it.
On Jan 11, 6:04Ā*am, delboy wrote: On 10 Jan, 20:47, Tom Gardner wrote: On Jan 10, 8:24Ā*pm, Gary Evans wrote: Quote from the book of Gore, chapter 7, verse 3. Numbers can be our friend if we use them correctly. As MacKay says ... In a climate where people donāt understand the numbers, newspapers, campaigners, companies, and politicians can get away with murder. We need simple numbers, and we need the numbers to be comprehen- sible, comparable, and memorable. With numbers in place, we will be better placed to answer questions such as these: 1) Can a country like Britain conceivably live on its own renewable en- ergy sources? 2) If everyone turns their thermostats one degree closer to the outside temperature, drives a smaller car, and switches off phone chargers when not in use, will an energy crisis be averted? 3) Should the tax on transportation fuels be signi?cantly increased? 4) Should speed-limits on roads be halved? 5) Is someone who advocates windmills over nuclear power stations āan enemy of the peopleā? 6) If climate change is āa greater threat than terrorism,ā should govern- ments criminalize āthe glori?cation of travelā and pass laws against āadvocating acts of consumptionā? 7) Will a switch to āadvanced technologiesā allow us to eliminate car- bon dioxide pollution without changing our lifestyle? 8) Should people be encouraged to eat more vegetarian food? 9) Is the population of the earth six times too big? Hopefully yes to question 1 and possibly question 7, and no to the rest. "Hopefully" is intellectually lazy; we need numbers and consequences (e.g. yes, X can happen provided that Y is halved, or whatever) MacKay gives such numbers and consequences, and presents a number of possible futures. As he says part way through the book We are drawing to the close of Part I. The assumption was that we want to get off fossil fuels, for one or more of the reasons listed in Chapter 1 ā climate change, security of supply, and so forth. Figure 18.9 shows how much power we currently get from renewables and nuclear. They amount to just 4% of our total power consumption. The two conclusions we can draw from Part I a 1. To make a difference, renewable facilities have to be country- sized. For any renewable facility to make a contribution comparable to our current consumption, it has to be country-sized. To get a big contribu- tion from wind, we used wind farms with the area of Wales. To get a big contribution from solar photovoltaics, we required half the area of Wales. To get a big contribution from waves, we imagined wave farms covering 500 km of coastline. To make energy crops with a big contribution, we took 75% of the whole country. Renewable facilities have to be country-sized because all renewables are so diffuse. Table 18.10 summarizes most of the powers-per- unit- area that we encountered in Part I. To sustain Britainās lifestyle on its renewables alone would be very difļ¬cult. A renewable-based energy solution will necessarily be large and intrusive. 2. Itās not going to be easy to make a plan that adds up using renewables alone. If we are serious about getting off fossil fuels, Brits are going to have to learn to start saying āyesā to something. Indeed to several somethings. In Part II Iāll ask, āassuming that we canāt get production from renew- ables to add up to our current consumption, what are the other options?ā |
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