Antonio Gasparini et. al. 2015 is an article in Lancet estimating global mortality from heat and cold, using an elaborate statistical process applied to an enormous collection of data, more than 74 million deaths across 384 locations in thirteen countries. It found mortality from cold, from temperatures in each place below that at which mortality was minimized, to be much larger, about seventeen times as large, as mortality from heat, similarly defined. It also found that mortality from both heat and cold was not mainly due to extreme temperatures, heat waves and cold waves, but to less extreme temperatures above or below the optimum.
What surprises me the most is the assumption many people make that the world is static -- that there are no technological advances and that people do not adapt even to gradually changing environments. Assuming a static world when in fact the world is getting more dynamic does not make sense to me.
The problem is that we don't know what technological changes will happen. One response is to conclude that we can't predict the things we want to predict — I made that point in _Future Imperfect_ for anything past the next few decades. Another is to calculate without technological change. If you are pretty sure of the sign of the change — medicine is going to get better — you can sometimes use the result as an upper or lower bound on the prediction.
In the case of adaptation I did find a way of doing at least a rough attempt at that, but Gasparini may have preferred not to try.
In some cases, such as Rennert et. al., I think the explanation is that they know what result they want, a high cost of carbon, so ignore any complications that would interfere with getting it, such as medical progress or the effect of income on vulnerability to weather. That one they could have tried to include but didn't.
I feel like I'm missing something right at the end. On the effects of technological progress in medicine and in protection from weather, you conclude: "they will reduce both the increased mortality from heat and the decreased mortality from cold." I don't see why such advances would reduce the decreased mortality from cold. In other words, you seem to be saying that medical and environmental technology advances will cause more people to die from cold. How can that be?
not more, fewer. If fewer people are dying from cold, warming will reduce mortality less. Similarly, if fewer people are dying from heat because of improved medicine, warming will increase mortality less.
The question isn't how tech advances change mortality but how they change the effect of warming on mortality.
Okay, thanks. That makes sense. I suspected I was interpreting incorrectly, and that was the case! The wording made this unclear. If you reduce a decrease, you are getting higher mortality.
I think the idea is that in the absence of global warming, technological change would have reduced deaths due to cold anyway. With global warming, there are fewer such deaths to reduce and so technological change doesn’t save as many lives from cold as it would have without global warming.
Regardless of other issues, it's disturbing that the authors report results based on "under the highest emission scenario", when 8.5 is thoroughly implausible. At this point, it would make sense to focus on projections based on RCP 2.6 and 4.5, not 6.0 and definitely not 8.5.
That's much better than many papers. However, they might have emphasized that 8.5 was not a plausible scenario. You know that news outlets are going to use the most extreme results and ignore the others...
I made that point in the post. Gasparini is ignoring lots of things in order to focus on the hard problem he is trying to solve.
I'm more concerned with his not pointing out that his mortality figure doesn't distinguish between loss of a month of life and loss of forty years of life. Even if he doesn't have the data to solve that problem he should have pointed it out, since his result, however good statistically, doesn't answer the question it appears to answer — what the costs are of climate change.
Based on actual death statistics from Europe regarding both "excess winter mortality" and deaths in heatwaves I believe that you will find that most of the deaths for either extreme cold or extreme heat are among the elderly.
Elderly people tend to not turn the heat up in the cold and to be chronically dehydrated which impacts how they handle hot temperatures
Roger Pielke Jr., has a lot about the way people keep using 8.5 even though it is generally agreed to be complete fiction. There is no way the RCP 8.5 pathway occurs.
See https://rogerpielkejr.substack.com/p/thou-shalt-use-rcp85 and links. One of which is Hausfather and Peters (2020) in which the authors "do not support a debate over over SSP5-8.5 plausibility. In fact, they claim the opposite: “Happily — and that’s a word we climatologists rarely get to use — the world imagined in RCP8.5 is one that, in our view, becomes increasingly implausible with every passing year.” "
Exactly. RCP8.5 assumes that the world's population will increase from 8 billion (now) to 12 billion (in 2100). Actual information makes that extremely unlikely. China, Russia, Portugal, Japan, ..., are already losing population, and by around 2060 the U.S. and many other countries will be doing so as well. Most estimates are that the world's population will be in the range 6.5 to 9 billion in 2100.
RCP8.5 also assumes all additional energy usage will come from burning coal. Highly unlikely.
Yes. The UN population estimates see global population just about stopping around 2100 but more sophisticated projections -- from IMHE and the Wittgenstein Center -- see the peak around the 2060s or 2080s. (The big wild card is Africa; Depending on which fertility scenario works out, the result varies by a billion.) It doesn't take legal coercion to change the mix of energy sources. Regardless of global temperatures, it would be sensible to greatly deregulate nuclear power.
No adaptation is almost as ludicrous as the use of RCP 8.5 (and as I commented else thread RCP 8.5 is not at all plausible as a scenario). Unless governments mandate the use of technology that doesn't work in abating heat, buildings all over the world will be built to adapt to higher temperatures. Mind you if governments mandate unreliable and intermittent electrical supplies (wind, solar) and don't have those decisions reversed by subsequent governments we could see increasing deaths from excess heat/cold, but these deaths are due to governments interfering rather than any change in temperatures.
One can get some idea of the size of adaptation, as I do, by looking at cities with different average temperatures. My examples were SJ vs Chicago and Tucson but that's a much bigger difference than between San Jose now and in 2099 under even RCP8.5. My regression result suggests that including it reduces the size of effects but by less than a factor of two.
I plan to redo the regression using only US cities, only developed world cities, and a few more categories to see if the result is being distorted by variables such as income that correlate with average temperature.
Adaptation can be quite inadvertent. As the population grows, new housing built to higher efficiency standards comes on stream. Growth causes the conversion of older units built to older, lower standards, to be destroyed. Over time, creative destruction causes the stock of housing to become more energy efficient.
This adaptation need not include mechanical processes like heating or cooling machinery. My new german made triple glazed windows are astoundingly warm. A 10' wide coolaroo roll down external shade [costing only $110] on my largest south facing window kept my house noticably cooler without blocking the garden view and costs nothing to operate. Despite claims of a record warm summer I didn't turn on the AC.
It seems to be that virtually no papers calculating the net costs/benefits of global warming are properly weighting the utility loss suffered by me, personally, because I hate the heat.
I have read your paper "A Theory of the Size and Shape of Nations" with great interest. I have a question about the equation on page 66 of the journal of political economy, where you derive the optimal size of a nation.
You write that Ri = VTi, where Ri is the revenue from territory i, V is the total volume of trade along a single trade route and Ti is t-nation i. Then you differentiate both sides with respect to Ti and get dRi/dTi = V - BTi, where B is a constant, to maximize revenue of t-nation i.
I don't understand how you get this result. If Ri = VTi, then dRi/dTi should be V, not V - BTi. Could you please explain how you obtain this equation?
Sorry for posting this here, perhaps it is irrelevant.
It's irrelevant here and I wrote that paper 46 years ago so would have to go back over it to answer your question. I may get around to doing so but no promise.
The .41 coefficient for the effect of ambient temperature on MMT comes from cities that have been there for a hundred years or more, and are presumably quite well adapted to their climates (until the last twenty years or so). But adaptation isn’t instantaneous, particularly if it involves building new housing, so you should probably use a smaller coefficient for shorter-term projections. And no, I have no idea how much smaller :-)
I did say that I was assuming that the effect of average temperature on MMT was the same across time as across space. I agree that it isn't perfect. Neither is the assumption that mortality depends only on temperature relative to MMT but I think it is better than the alternative assumption Gasparini is implicitly making.
Thanks, David. Excellent as usual.
What surprises me the most is the assumption many people make that the world is static -- that there are no technological advances and that people do not adapt even to gradually changing environments. Assuming a static world when in fact the world is getting more dynamic does not make sense to me.
The problem is that we don't know what technological changes will happen. One response is to conclude that we can't predict the things we want to predict — I made that point in _Future Imperfect_ for anything past the next few decades. Another is to calculate without technological change. If you are pretty sure of the sign of the change — medicine is going to get better — you can sometimes use the result as an upper or lower bound on the prediction.
In the case of adaptation I did find a way of doing at least a rough attempt at that, but Gasparini may have preferred not to try.
In some cases, such as Rennert et. al., I think the explanation is that they know what result they want, a high cost of carbon, so ignore any complications that would interfere with getting it, such as medical progress or the effect of income on vulnerability to weather. That one they could have tried to include but didn't.
I feel like I'm missing something right at the end. On the effects of technological progress in medicine and in protection from weather, you conclude: "they will reduce both the increased mortality from heat and the decreased mortality from cold." I don't see why such advances would reduce the decreased mortality from cold. In other words, you seem to be saying that medical and environmental technology advances will cause more people to die from cold. How can that be?
not more, fewer. If fewer people are dying from cold, warming will reduce mortality less. Similarly, if fewer people are dying from heat because of improved medicine, warming will increase mortality less.
The question isn't how tech advances change mortality but how they change the effect of warming on mortality.
Okay, thanks. That makes sense. I suspected I was interpreting incorrectly, and that was the case! The wording made this unclear. If you reduce a decrease, you are getting higher mortality.
I think the idea is that in the absence of global warming, technological change would have reduced deaths due to cold anyway. With global warming, there are fewer such deaths to reduce and so technological change doesn’t save as many lives from cold as it would have without global warming.
Regardless of other issues, it's disturbing that the authors report results based on "under the highest emission scenario", when 8.5 is thoroughly implausible. At this point, it would make sense to focus on projections based on RCP 2.6 and 4.5, not 6.0 and definitely not 8.5.
They report results under all four scenarios.
That's much better than many papers. However, they might have emphasized that 8.5 was not a plausible scenario. You know that news outlets are going to use the most extreme results and ignore the others...
I made that point in the post. Gasparini is ignoring lots of things in order to focus on the hard problem he is trying to solve.
I'm more concerned with his not pointing out that his mortality figure doesn't distinguish between loss of a month of life and loss of forty years of life. Even if he doesn't have the data to solve that problem he should have pointed it out, since his result, however good statistically, doesn't answer the question it appears to answer — what the costs are of climate change.
Based on actual death statistics from Europe regarding both "excess winter mortality" and deaths in heatwaves I believe that you will find that most of the deaths for either extreme cold or extreme heat are among the elderly.
Elderly people tend to not turn the heat up in the cold and to be chronically dehydrated which impacts how they handle hot temperatures
Roger Pielke Jr., has a lot about the way people keep using 8.5 even though it is generally agreed to be complete fiction. There is no way the RCP 8.5 pathway occurs.
See https://rogerpielkejr.substack.com/p/thou-shalt-use-rcp85 and links. One of which is Hausfather and Peters (2020) in which the authors "do not support a debate over over SSP5-8.5 plausibility. In fact, they claim the opposite: “Happily — and that’s a word we climatologists rarely get to use — the world imagined in RCP8.5 is one that, in our view, becomes increasingly implausible with every passing year.” "
Exactly. RCP8.5 assumes that the world's population will increase from 8 billion (now) to 12 billion (in 2100). Actual information makes that extremely unlikely. China, Russia, Portugal, Japan, ..., are already losing population, and by around 2060 the U.S. and many other countries will be doing so as well. Most estimates are that the world's population will be in the range 6.5 to 9 billion in 2100.
RCP8.5 also assumes all additional energy usage will come from burning coal. Highly unlikely.
Yes. The UN population estimates see global population just about stopping around 2100 but more sophisticated projections -- from IMHE and the Wittgenstein Center -- see the peak around the 2060s or 2080s. (The big wild card is Africa; Depending on which fertility scenario works out, the result varies by a billion.) It doesn't take legal coercion to change the mix of energy sources. Regardless of global temperatures, it would be sensible to greatly deregulate nuclear power.
No adaptation is almost as ludicrous as the use of RCP 8.5 (and as I commented else thread RCP 8.5 is not at all plausible as a scenario). Unless governments mandate the use of technology that doesn't work in abating heat, buildings all over the world will be built to adapt to higher temperatures. Mind you if governments mandate unreliable and intermittent electrical supplies (wind, solar) and don't have those decisions reversed by subsequent governments we could see increasing deaths from excess heat/cold, but these deaths are due to governments interfering rather than any change in temperatures.
One can get some idea of the size of adaptation, as I do, by looking at cities with different average temperatures. My examples were SJ vs Chicago and Tucson but that's a much bigger difference than between San Jose now and in 2099 under even RCP8.5. My regression result suggests that including it reduces the size of effects but by less than a factor of two.
I plan to redo the regression using only US cities, only developed world cities, and a few more categories to see if the result is being distorted by variables such as income that correlate with average temperature.
Adaptation can be quite inadvertent. As the population grows, new housing built to higher efficiency standards comes on stream. Growth causes the conversion of older units built to older, lower standards, to be destroyed. Over time, creative destruction causes the stock of housing to become more energy efficient.
This adaptation need not include mechanical processes like heating or cooling machinery. My new german made triple glazed windows are astoundingly warm. A 10' wide coolaroo roll down external shade [costing only $110] on my largest south facing window kept my house noticably cooler without blocking the garden view and costs nothing to operate. Despite claims of a record warm summer I didn't turn on the AC.
It seems to be that virtually no papers calculating the net costs/benefits of global warming are properly weighting the utility loss suffered by me, personally, because I hate the heat.
Just move south a little.
I have read your paper "A Theory of the Size and Shape of Nations" with great interest. I have a question about the equation on page 66 of the journal of political economy, where you derive the optimal size of a nation.
You write that Ri = VTi, where Ri is the revenue from territory i, V is the total volume of trade along a single trade route and Ti is t-nation i. Then you differentiate both sides with respect to Ti and get dRi/dTi = V - BTi, where B is a constant, to maximize revenue of t-nation i.
I don't understand how you get this result. If Ri = VTi, then dRi/dTi should be V, not V - BTi. Could you please explain how you obtain this equation?
Sorry for posting this here, perhaps it is irrelevant.
It's irrelevant here and I wrote that paper 46 years ago so would have to go back over it to answer your question. I may get around to doing so but no promise.
The .41 coefficient for the effect of ambient temperature on MMT comes from cities that have been there for a hundred years or more, and are presumably quite well adapted to their climates (until the last twenty years or so). But adaptation isn’t instantaneous, particularly if it involves building new housing, so you should probably use a smaller coefficient for shorter-term projections. And no, I have no idea how much smaller :-)
I did say that I was assuming that the effect of average temperature on MMT was the same across time as across space. I agree that it isn't perfect. Neither is the assumption that mortality depends only on temperature relative to MMT but I think it is better than the alternative assumption Gasparini is implicitly making.