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Quote from: Tim the Plumber on 16/06/2017 18:01:12Quote from: chiralSPO on 16/06/2017 17:56:04Regarding mechanism of temperature leading to more extreme weather:The amount of water that can go into the air (vapor pressure) increases with higher temperature. But that increase is not linear, it increases increasingly with higher temperature (see a data table here: http://www.wiredchemist.com/chemistry/data/vapor-pressure )This leads to greater rainfall events with higher temperatures. Consider this: at 25 °C the vapor pressure of water is 23.8 mmHg, but at 20 °C the vapor pressure is only 17.5 mmHg. That means high humidity air at 25 °C would have to lose 6.3 mmHg worth of water on cooling by 5 °C. An increase of 2 °C (which is now essentially unavoidable) changes these numbers to 26.7 mmHg at 27 °C and 19.8 mmHg at 22 °C, a difference of 6.9 mmHg, meaning that 10% more rain would fall. This doesn't sound too scary, but this difference is more exaggerated on more extreme weather.In a major thunderstorm, humid air can be cooled from over 35 °C to 0 °C (based on our chart that's a difference of 37.6 mmHg or 36 metric tons of rain per km3 of air). Bumping the surface temp up by 2 °C to 37 °C does not change the 0 °C, which is set by altitude, so the rainfall increases to 41 metric tons of rain per km3 of air (an increase of almost 14%.)Thank you for a good post.You are most welcome :-)Quote from: Tim the Plumber on 16/06/2017 18:01:12The counter point to that is that there has been no such increase in storm intensity.But there has been and is. See here: https://skepticalscience.com/hurricanes-global-warming-intermediate.htm and here: https://www.epa.gov/climate-indicators/climate-change-indicators-tropical-cyclone-activity and here: https://www.ncdc.noaa.gov/sotc/national/201513 Although, I will point out, Australia seems to be getting a reprieve: http://www.bom.gov.au/cyclone/climatology/trends.shtml but that appears to be largely due to a change in target, as Southeast Asia is seeing an uptick in storm risk: http://www.nature.com/nclimate/journal/v2/n4/abs/nclimate1410.htmlQuote from: Tim the Plumber on 16/06/2017 18:01:12It is also a matter of the additional energy required to get all that water into the cloud. The proposed level of forcing is at most 4 W/m2 (from memory and there are lots of numbers about) from a doubling of CO2.That there would be a general increase in rainfall is I think reasonable. But over most of the world that is a very good thing. Over the wet parts the slight increase in rainfall would be only noticable to those looking at the weather data. It might be a good thing if the rainfall is distributed over time, but my understanding of the models is that the frequency of the storms is not expected to change that much, instead the rainfalls would be more extreme. Yes Arizona is dry, but this: //www.youtube.com/watch?v=jI8d92SWMKw is not what they need. (Click the video)
Quote from: chiralSPO on 16/06/2017 17:56:04Regarding mechanism of temperature leading to more extreme weather:The amount of water that can go into the air (vapor pressure) increases with higher temperature. But that increase is not linear, it increases increasingly with higher temperature (see a data table here: http://www.wiredchemist.com/chemistry/data/vapor-pressure )This leads to greater rainfall events with higher temperatures. Consider this: at 25 °C the vapor pressure of water is 23.8 mmHg, but at 20 °C the vapor pressure is only 17.5 mmHg. That means high humidity air at 25 °C would have to lose 6.3 mmHg worth of water on cooling by 5 °C. An increase of 2 °C (which is now essentially unavoidable) changes these numbers to 26.7 mmHg at 27 °C and 19.8 mmHg at 22 °C, a difference of 6.9 mmHg, meaning that 10% more rain would fall. This doesn't sound too scary, but this difference is more exaggerated on more extreme weather.In a major thunderstorm, humid air can be cooled from over 35 °C to 0 °C (based on our chart that's a difference of 37.6 mmHg or 36 metric tons of rain per km3 of air). Bumping the surface temp up by 2 °C to 37 °C does not change the 0 °C, which is set by altitude, so the rainfall increases to 41 metric tons of rain per km3 of air (an increase of almost 14%.)Thank you for a good post.
Regarding mechanism of temperature leading to more extreme weather:The amount of water that can go into the air (vapor pressure) increases with higher temperature. But that increase is not linear, it increases increasingly with higher temperature (see a data table here: http://www.wiredchemist.com/chemistry/data/vapor-pressure )This leads to greater rainfall events with higher temperatures. Consider this: at 25 °C the vapor pressure of water is 23.8 mmHg, but at 20 °C the vapor pressure is only 17.5 mmHg. That means high humidity air at 25 °C would have to lose 6.3 mmHg worth of water on cooling by 5 °C. An increase of 2 °C (which is now essentially unavoidable) changes these numbers to 26.7 mmHg at 27 °C and 19.8 mmHg at 22 °C, a difference of 6.9 mmHg, meaning that 10% more rain would fall. This doesn't sound too scary, but this difference is more exaggerated on more extreme weather.In a major thunderstorm, humid air can be cooled from over 35 °C to 0 °C (based on our chart that's a difference of 37.6 mmHg or 36 metric tons of rain per km3 of air). Bumping the surface temp up by 2 °C to 37 °C does not change the 0 °C, which is set by altitude, so the rainfall increases to 41 metric tons of rain per km3 of air (an increase of almost 14%.)
The counter point to that is that there has been no such increase in storm intensity.
It is also a matter of the additional energy required to get all that water into the cloud. The proposed level of forcing is at most 4 W/m2 (from memory and there are lots of numbers about) from a doubling of CO2.That there would be a general increase in rainfall is I think reasonable. But over most of the world that is a very good thing. Over the wet parts the slight increase in rainfall would be only noticable to those looking at the weather data.
I will also add that there is currently a record-setting heat wave across the Southwestern corner of the US. Phoenix Arizona (same location as the rainburst I mentioned in my last post) reached 118 °F yesterday (48 °C). This is a tie with the record temp, which was set last year. I will point out that the mechanism by which global warming increases the maximum temperatures observed is well understood, and to some extent self-explanatory.Where the economics/human suffer comes in is this:1) some of the roadways have melted! The expense of repairing these roads would not necessarily be that much more than the "traffic light rule of thumb" proposed by Tim, but updating all the roadways to be rated for higher temps will be massively expensive!
2) Electricity usage spiked because everybody needed their AC. But the local power can't keep up, and they have rolling blackouts (eek). This is not only dangerous for those who are depending on AC for maintaining livable conditions at home (there have been some deaths reported), but also throws a wrench in the works for businesses, hospitals, factories etc.
3) Oh, and remember how the roads are melting? Similar problems at the airport...So, if the average temperatures creep up another 2–3 °C over the next 30 years, these people could be facing yearly heat waves the pass 50 °C! Did I mention the humidity is increasing too?
Quote from: jeffreyH on 16/06/2017 18:20:24And this is why Tim. Read it carefully.https://en.m.wikipedia.org/wiki/1997%E2%80%9398_El_Ni%C3%B1o_eventNo.I will not read a load of drivel you want to throw at me to avoid actually answering anything yourself.To pass this challenge you have to;1, Choose 1 aspect/effect/issue of a slighly warmer world that is bad.2, Then in your own words, describe the mechanism that will cause this. 3, Then support this mechanism with some science.4, Then I will read it and look at it. If it is more bad than would be sorted out with the budget of traffic lights for any local council that has them you win.Otherwise you demonstrate that you have no clue at all.
And this is why Tim. Read it carefully.https://en.m.wikipedia.org/wiki/1997%E2%80%9398_El_Ni%C3%B1o_event
Quote from: chiralSPO on 20/06/2017 16:09:53I will also add that there is currently a record-setting heat wave across the Southwestern corner of the US. Phoenix Arizona (same location as the rainburst I mentioned in my last post) reached 118 °F yesterday (48 °C). This is a tie with the record temp, which was set last year. I will point out that the mechanism by which global warming increases the maximum temperatures observed is well understood, and to some extent self-explanatory.Where the economics/human suffer comes in is this:1) some of the roadways have melted! The expense of repairing these roads would not necessarily be that much more than the "traffic light rule of thumb" proposed by Tim, but updating all the roadways to be rated for higher temps will be massively expensive!But they will be maintained over time and if different ratios of tar are to be used like they do in hotter places the net cost is tiny.
Quote2) Electricity usage spiked because everybody needed their AC. But the local power can't keep up, and they have rolling blackouts (eek). This is not only dangerous for those who are depending on AC for maintaining livable conditions at home (there have been some deaths reported), but also throws a wrench in the works for businesses, hospitals, factories etc.Again, we need to establish a direct link that says that this is due to global warming from CO2. How many deaths? How do you know that this is not within normal variability of weather? How many deaths are not happening due to warmer winters?Quote3) Oh, and remember how the roads are melting? Similar problems at the airport...So, if the average temperatures creep up another 2–3 °C over the next 30 years, these people could be facing yearly heat waves the pass 50 °C! Did I mention the humidity is increasing too?How big a trouble is this? Iran often has such temperatures. They manage. How would the airport manage if all flights were canceled due to the panic over CO2? If you want a decent airport with easy flights then you will have to accept the CO2 that that will inevitable mean. Unlucky.
2, The link https://www.epa.gov/climate-indicators/climate-change-indicators-tropical-cyclone-activity shows a graph of no real difference. It shows that there has not been any change in the amount of huricanes in the Atlantic.
3, The next one is long. Which bit of it says that there is a link? How do they explain this in a detailed mechanism? Can you explain this mechanism yourself? Can you quote from it to show that you have read it and undeerstand it? How big is it?
Quote from: Tim the Plumber on 24/06/2017 14:23:53Quote from: jeffreyH on 16/06/2017 18:20:24And this is why Tim. Read it carefully.https://en.m.wikipedia.org/wiki/1997%E2%80%9398_El_Ni%C3%B1o_eventNo.I will not read a load of drivel you want to throw at me to avoid actually answering anything yourself.To pass this challenge you have to;1, Choose 1 aspect/effect/issue of a slighly warmer world that is bad.2, Then in your own words, describe the mechanism that will cause this. 3, Then support this mechanism with some science.4, Then I will read it and look at it. If it is more bad than would be sorted out with the budget of traffic lights for any local council that has them you win.Otherwise you demonstrate that you have no clue at all.If you won't read it then you are showing yourself to be foolish. Anyone else reading it will get it. Except you won't since you don't care about evidence. Bye.
Quote from: Tim the Plumber on 24/06/2017 14:29:372, The link https://www.epa.gov/climate-indicators/climate-change-indicators-tropical-cyclone-activity shows a graph of no real difference. It shows that there has not been any change in the amount of huricanes in the Atlantic.Correct, there has not been a change in the frequency of the storms. But figure 3 clearly shows an increase in the storm *intensity*
According to the total annual ACE Index, cyclone intensity has risen noticeably over the past 20 years, and six of the 10 most active years since 1950 have occurred since the mid-1990s (see Figure 2). Relatively high levels of cyclone activity were also seen during the 1950s and 1960s.
Quote from: Tim the Plumber on 24/06/2017 14:29:373, The next one is long. Which bit of it says that there is a link? How do they explain this in a detailed mechanism? Can you explain this mechanism yourself? Can you quote from it to show that you have read it and undeerstand it? How big is it?The noaa one? That is not about mechanism, it is a summary of a few dozen climate metrics, and how they have changed in different regions over the past few decades. It clearly shows that there are changing weather patterns (not just weather) across the entire US, with changes in seasonal weather, rainfall amounts (some areas increase, some decrease) temperatures (increasing everywhere), and it shows the increasing rates of record-breaking weather (events and averages).
Quote from: Tim the Plumber on 24/06/2017 14:35:17Quote from: chiralSPO on 20/06/2017 16:09:53I will also add that there is currently a record-setting heat wave across the Southwestern corner of the US. Phoenix Arizona (same location as the rainburst I mentioned in my last post) reached 118 °F yesterday (48 °C). This is a tie with the record temp, which was set last year. I will point out that the mechanism by which global warming increases the maximum temperatures observed is well understood, and to some extent self-explanatory.Where the economics/human suffer comes in is this:1) some of the roadways have melted! The expense of repairing these roads would not necessarily be that much more than the "traffic light rule of thumb" proposed by Tim, but updating all the roadways to be rated for higher temps will be massively expensive!But they will be maintained over time and if different ratios of tar are to be used like they do in hotter places the net cost is tiny.They have to switch from asphalt to concrete. There are pros and cons to each, and it is not clear which one is cheaper, but changing from one to the other is a big project.QuoteQuote2) Electricity usage spiked because everybody needed their AC. But the local power can't keep up, and they have rolling blackouts (eek). This is not only dangerous for those who are depending on AC for maintaining livable conditions at home (there have been some deaths reported), but also throws a wrench in the works for businesses, hospitals, factories etc.Again, we need to establish a direct link that says that this is due to global warming from CO2. How many deaths? How do you know that this is not within normal variability of weather? How many deaths are not happening due to warmer winters?Quote3) Oh, and remember how the roads are melting? Similar problems at the airport...So, if the average temperatures creep up another 2–3 °C over the next 30 years, these people could be facing yearly heat waves the pass 50 °C! Did I mention the humidity is increasing too?How big a trouble is this? Iran often has such temperatures. They manage. How would the airport manage if all flights were canceled due to the panic over CO2? If you want a decent airport with easy flights then you will have to accept the CO2 that that will inevitable mean. Unlucky.Yes, those in the Middle East can deal with these temperatures. I never claimed that this was an insurmountable problem. That wasn't the "challenge." You were looking for substantial increased cost. Air conditioning (both hardware and energy) is very costly. And the higher the outside temperature, the more costly it is to keep the inside livable. Also, since you brought it up, let us consider Iran and the Middle East as global temperatures rise: An article from last year ( https://link.springer.com/content/pdf/10.1007%2Fs10584-016-1665-6.pdf ) shows that since the turn of the century, much of the Middle East and North Africa has had hotter and longer heat waves during the summer months than they were in the 70s, 80s and 90s. Furthermore, they use several computational models which predict that by 2100, there will be on average about seven days of the year with high temperatures over 50 °C, and lows above 30 °C.Again, because it apparently needs repetition, the problem is not that the world will be a particular temperature. The problem is how quickly it will change, and how expensive it will be to keep up.Much of the cost of infrastructure is determined by its maximum capacity, which is determined by the extreme cases that one expects: Storm water systems are designed to handle downpours of multiple inches of rain per hour, even though this might only happen once or twice in a year, when it does happen you need a system that can handle it. So when the worst case scenario gets worse, you need to update the whole system. Similarly buildings need AC systems that can handle the hottest days of the year, and when that changes from 40 °C to 42 °C across much of Europe and Northern America over the next 50 years, you better bet that the cost of AC upgrades is going to reflect that. One more example: building codes for areas that are threatened by hurricanes and tornados--as maximum wind speeds and maximum storm surges increase, buildings will have to be reinforced or raised to accommodate the new maximal threats.
As you said it is not clear which is more expensive, concrete or tarmac. So there is obviously not going to be a large cost increase as all roads have to be remade/repaired all the time.
Quote from: jeffreyH on 24/06/2017 16:19:05Quote from: Tim the Plumber on 24/06/2017 14:23:53Quote from: jeffreyH on 16/06/2017 18:20:24And this is why Tim. Read it carefully.https://en.m.wikipedia.org/wiki/1997%E2%80%9398_El_Ni%C3%B1o_eventNo.I will not read a load of drivel you want to throw at me to avoid actually answering anything yourself.To pass this challenge you have to;1, Choose 1 aspect/effect/issue of a slighly warmer world that is bad.2, Then in your own words, describe the mechanism that will cause this. 3, Then support this mechanism with some science.4, Then I will read it and look at it. If it is more bad than would be sorted out with the budget of traffic lights for any local council that has them you win.Otherwise you demonstrate that you have no clue at all.If you won't read it then you are showing yourself to be foolish. Anyone else reading it will get it. Except you won't since you don't care about evidence. Bye.The fact that you cannot quote from it shows that you have not read it.The fact that you cannot explain it your self shows you do not understand it.The fact that you choose to avoid making any attempt at answering the challeng shows that you know you can't.
Quote from: Tim the Plumber on 25/06/2017 06:35:08As you said it is not clear which is more expensive, concrete or tarmac. So there is obviously not going to be a large cost increase as all roads have to be remade/repaired all the time. Except that it's obvious that there will be a large cost because all the roads will need to be upgraded on a fast schedule based on the weather, rather than a slow schedule based on wear and tear (or equivalently, that wear and tear will be much faster).
In December of 1999 there was another event.https://en.m.wikipedia.org/wiki/Vargas_tragedy"The 1999 Vargas tragedy was a disaster that struck the Vargas State of Venezuela on 15 December 1999, when the torrential rains and the flash floods and debris flows that followed on December 14–16 which killed tens of thousands of people, destroyed thousands of homes, and led to the complete collapse of the state's infrastructure. According to relief workers, the neighborhood of Los Corales was buried under 3 metres (9.8 ft) of mud and a high percentage of homes were simply swept away to the ocean. Whole towns like Cerro Grande and Carmen de Uria completely disappeared. As much as 10% of the population of Vargas perished during this event."It would need to be diamond encrusted gold traffic lights to outdo this.
Quote from: jeffreyH on 25/06/2017 14:47:03In December of 1999 there was another event.https://en.m.wikipedia.org/wiki/Vargas_tragedy"The 1999 Vargas tragedy was a disaster that struck the Vargas State of Venezuela on 15 December 1999, when the torrential rains and the flash floods and debris flows that followed on December 1416 which killed tens of thousands of people, destroyed thousands of homes, and led to the complete collapse of the state's infrastructure. According to relief workers, the neighborhood of Los Corales was buried under 3 metres (9.8 ft) of mud and a high percentage of homes were simply swept away to the ocean. Whole towns like Cerro Grande and Carmen de Uria completely disappeared. As much as 10% of the population of Vargas perished during this event."It would need to be diamond encrusted gold traffic lights to outdo this.Yet again;1, show the mechanism that links this to global warming.2, describe it yourself.3, link to some sort of supporting science.4, Then we can look at it and see how big an issue it will be.
In December of 1999 there was another event.https://en.m.wikipedia.org/wiki/Vargas_tragedy"The 1999 Vargas tragedy was a disaster that struck the Vargas State of Venezuela on 15 December 1999, when the torrential rains and the flash floods and debris flows that followed on December 1416 which killed tens of thousands of people, destroyed thousands of homes, and led to the complete collapse of the state's infrastructure. According to relief workers, the neighborhood of Los Corales was buried under 3 metres (9.8 ft) of mud and a high percentage of homes were simply swept away to the ocean. Whole towns like Cerro Grande and Carmen de Uria completely disappeared. As much as 10% of the population of Vargas perished during this event."It would need to be diamond encrusted gold traffic lights to outdo this.