We are in the middle of yet another atypical hurricane season. Between hurricane Florence in America and typhoon Mangkhut in the Philippines and China, both hemispheres have been hit almost simultaneously by unusually strong storm systems. As a result, many people are again pointing a finger at climate change. This is not an unreasonable response, but it is one that we should be cautious about, because it is very easy to fall victim to the same logical blunder that often ensnares climate change deniers: confusing weather with climate. What we really need to know is whether there is a consistent pattern of increasing extreme weather events (spoiler alert: there is), so that is what I want to look at in this post (I’ll return to the topic of individual storm systems at the end). I’m going to briefly discuss the literature on extreme weather events to see if there is evidence that climate change is increasing their frequency and/or intensity. For the sake of brevity, I’ll just focus on three major categories of extreme weather: heatwaves, precipitation (both droughts and floods), and hurricanes (aka cyclones, aka typhoons; they are all the same type of storm, the names just differ in different parts of the world, but since most of my readers are American, I will refer to them all as hurricanes throughout).
Before I begin, I want to point out that this is a very important topic for understanding the consequences of anthropogenic climate change, because the extremes are potentially the most dangerous aspect of climate change. If you think about heatwaves for a second, this should make sense. Summers are already hot, but for the most part, they are bearable. They only really become a problem when we have consecutive days of abnormally hot weather (i.e., heatwaves). Thus, having a summer where the temperature is consistently 1°C above normal is inconvenient, but not critical (strictly in terms of the heat itself). However, having a summer with heatwaves that are more frequent and more intense is a far more serious dilemma. That type of summer is far more likely to cause heat strokes and various other problems. Similarly, having an average increase in rainfall (with low variation) is not nearly as problematic as having an increase in the number of massive, flash flood-inducing downpours. So, if we are going to talk about the potential damage and cost (economically, physically, and environmentally) of climate change, it’s important to discuss the extremes.
I’d also like to briefly state that the evidence is extremely clear that we are the primary cause of the current warming. Discussing that evidence is beyond the scope of this post, but I have previously done so here and here, as well as debunking most of the common arguments to the contrary here. Please read those posts before commenting with an argument that it’s not our fault.
Heatwaves
Let’s start with the easy one. As its name suggests, global warming is resulting in a planet that is, on average, warming. Currently, the four hottest years on record are 2014, 2015, 2016, and 2017 (not in that order), and if current trends continue, 2018 will join their ranks, meaning that all five of the top five hottest years will have occurred in the past five years. Based on these increases in mean temperatures, it is hardly surprising that in many areas heatwaves have also been increasing and that increase is linked with global climate change (Klein Tank and Konnen 2003; Della-Marta et al. 2007; Tanarhte et al. 2015; Habeeb et al. 2015). Indeed, Perkins et al. (2012) found that, globally, the intensity, frequency, and duration of heatwaves is increasing. In other words, heatwaves are becoming hotter, we are experiencing more of them, and they are lasting longer (Habeeb et al. 2015). Further, other research has found that not only are heatwaves increasing, but the areas that are affected by them are expanding (Russo et al. 2014).
All of that is really bad, because despite common perceptions to the contrary, heatwaves are actually the most dangerous natural disaster in terms of human mortality. According to the CDC, in the US, heat kills more people than tornadoes, floods, lightning, or hurricanes. Indeed, the death tolls during large heatwaves can be staggering. For example, during 2003, Europe experience a record-breaking heatwave (far beyond expectations for natural weather patterns; Schar et al. 2004; Stott et al. 2004) that resulted in over 70,000 deaths (Robine 2008), with nearly 15,000 deaths in France alone (Argaud et al. 2007)! Let that sink in for a minute. This heatwave was so bad that it killed nearly 15,000 people in a single country.
To be clear, none of this is fearmongering, speculation, or “liberal propaganda.” These are simple facts. People are dying as a direct result of climate change, and the situation will continue to get worse if we don’t take action (Meehl et al. 2004; Luber et al. 2008; Lelieveld et al. 2016).
Extreme precipitation
One of the things that people often find confusing about climate change is that the effects are different in different areas. Indeed, some areas are expected to experience increased precipitation (to the point of flooding), while others are expected to experience increased drought. Sometimes people jump on this fact and claim that climate scientists are simply making things up and claiming that everything is climate change no matter what weather we experience. but such claims are untrue. If you actually read the literature and look at the models, they clearly predicted beforehand that the patterns of change will not be uniform (i.e., some areas will have droughts while others have floods; though the net effect should be increased precipitation globally). Further, we aren’t running around arbitrarily claiming that changes in precipitation are due to climate change. Rather, we are very carefully studying the changes in wind currents, evaporation rates, etc. so that we understand the underlying mechanisms that are driving the changes. Finally, despite common claims to the contrary, our observations are actually pretty consistent with models’ predictions (Dai 2012; more sources and details here).
Describing these mechanisms in detail is far beyond the scope of this post, but two major patterns seem to be at play. First, many areas will experience more of the extremes of their typical weather patterns (Dai and Trenberth 1998). In other words, if you live in a fairly wet area, it is probably going to become wetter, and if you live in a fairly dry area, it is probably going to become drier. Again, this situation of exaggerated extremes is problematic. Dry areas already struggle with not having enough water, while wet areas already struggle with having too much of it, and climate change is expected to make both of those situations worse. The second pattern, which is related to the first, is that, in many cases, more precipitation is expected at high latitudes, while less precipitation is expected in the arid sub-tropics (Trenberth 2011).
So, what are we actually observing? In short, there is a net increase in precipitation globally (Alexander et al. 2006), and some areas are experiencing more extreme downpours (Dai and Trenberth 1998; Groisman et al. 2005; Trenberth 2011), while dry areas are experiencing more droughts (Dai and Trenberth 1998; Dai 2010; Trenberth 2011). These downpours and droughts in turn are resulting in increased floods and wildfires (respectively), increased damage to crops, increased damage to ecosystems, increased damage to property, increased loss of human life, etc. (Rosenzweig et al. 2001; Milly et al. 2002; Flannigan et al. 2009; Carnicer et al. 2010; Schlenker and Lobell). Further, I want to make it clear again that scientists aren’t running around arbitrarily blaming climate change for these events. We have carefully studied the underlying mechanisms of these precipitation extremes and found that the current trends are unlikely to be natural and are linked to human-induced increases in temperature (Held and Soden 2006; Allan and Soden. 2008; Min et al. 2011).
Cyclones/hurricanes/typhoons
These storm systems are probably the ones that get the most attention in the press and general public, but they are, unfortunately, some of the hardest to study. This is because they are infrequent (resulting in small sample sizes per year) and because record keeping for them has been surprisingly inconsistent, making it difficult to look at long-term patterns. Having said that, we have sufficient data from the past few decades to draw some conclusions. Before I get to those though, I want to talk about scientists’ expectations, because most models don’t actually predict an increase in the total number of tropical storms (in some cases they actually predict a slight decrease). Rather, the prediction is that the storms will increase in intensity, and really intense storms will become more common. In other words, the total number of hurricanes per year should stay the same or go down slightly, but we expect more of those hurricanes to be very large, powerful storms (e.g., category 4 and 5 hurricanes). As with everything else that I have talked about thus far, that is problematic because the extremes are where most of the damage comes from. Having the same total number of hurricanes but more category 4s is worse than having a greater total number of hurricanes with mostly category 1s and 2s.
So, with all of this in mind, let’s once again look at what we have actually found. Walsh et al (2016) published a fairly recent review of this topic, so I recommend reading them for more details and sources, but in short, what we’ve found is that there is a general increase in both storm intensity and the proportion of storms that are really powerful (e.g., 4s and 5s), but the total number of hurricanes has not increased (Emanuel 2005; Elsner et al. 2008; Holland and Bruyere 2014). Also, the trends are more pronounced in some areas than others, with the North Atlantic basin (i.e., the one that affects the US) showing the strongest patterns. Another interesting and alarming result is that hurricanes are moving further away from the tropics and towards the poles (Kossin et al. 2014). In other words, as the planet warms, the tropics are expanding north and south of the equator, and, as a result, powerful hurricanes can strike further north and further south than they could previously. Thus, cities that have never had serious hurricane problems may now be faced with strong storm systems.
Update 2019: There is increasing evidence that hurricanes are also “stalling” more frequently. In other words, they are staying in one area for longer, thus resulting in increased damage (Kossin 2018; Hall and Kossin 2019).
As a final note, the damage caused by these systems is also increasing not only because the storms are becoming more intense, but also because sea level rise is resulting in increased storm surge and flooding.
The influence of climate change
Before I conclude this post, I want to return briefly to the topic of blaming particular storm systems on climate change, because that situation is actually more complex than most people give it credit for. In short, we can never say with 100% probability that climate change caused a particular extreme weather event, but, based on all of the data that I have discussed, we can confidently say that climate change is making these events more likely, and for any particular event, it is likely that climate change played a role.
Let me use smoking as an example. If a regular smoker is diagnosed with cancer, you can never say with 100% certainty that smoking caused the cancer. It is always possible that they would have developed cancer even if they never smoked. However, because we know that there is an overarching causal relationship between smoking and cancer, we can say that smoking very likely contributed to their cancer and that, in general, smoking rates contribute to cancer rates. The same thing is true with climate change and storms. Because of the known causal relationships between temperatures and extreme weather events, for many extreme events, we can state that climate change likely played a role in them and that, in general, increased climate change is resulting in increased extremes.
Additionally, in the case of climate change, we can often go even further. By examining natural trends, our influence on the climate, and the causes of particular storm systems, we can often calculate the probability that a given system would arise absent our influence (and, conversely, how likely it is that our actions played a role). Indeed, several of the studies that I have cited throughout this post have done that. For example, as I mentioned earlier, when scientists examined the 2003 heatwave in Europe, they found that it was unlikely based on natural patterns (Schar et al. 2004) and that our actions have doubled the risk of such events (Stott et al. 2004). So, while we should be cautious about blaming everything on climate change, there is often very good evidence that particular events were probably influenced by our actions.
Conclusion
In short, there is very clear evidence that extreme weather events are increasing, and that increase is linked to climate change (which we are causing). Heat waves, floods, and droughts are all on the rise, and they bring with them heavy economic, environmental, and health burdens, with thousands of people dying as a result of them. Further, the intensity of these events is increasing as well as their frequency. Similarly, for hurricanes, storms are becoming more intense, and the strongest, most dangerous categories are becoming more common. This is a very real and dangerous consequence of our actions.
Again, this is not fearmongering or “liberal propaganda,” it’s not something that will only happen in the distant future, and it certainly isn’t a Chinese hoax. This is real, and it is happening right now. People are already dying as a direct result of what we are doing to the atmosphere, and those death tolls will only become worse if we don’t immediately take action to stop the climate from changing any further. I rarely include calls to action in my posts (other than encouraging people to fact check and think critically), but this topic is far too important for me to end the post without one. We need to start taking climate change seriously and stop relying on fossil fuels, even if it costs some jobs, increases taxes, etc. The cost of not taking action will be far, far higher than the cost of taking action, both economically and in terms of human lives. Thousands have already died because of climate change, and thousands more, probably millions more, will die if we don’t change our actions. We have the technology right now to make a huge difference, we just need to invest in it, and that means that you need to take personal responsibility in your daily choices and, perhaps most importantly of all, you need to contact your governmental representatives and tell them that this needs to be a priority. Then, you need to vote accordingly.
Note: In all likelihood, switching energy sources would actually result in a net increase in jobs and net increase in the economy, but even if that wasn’t true, the jobs of a few coal miners and bank accounts of rich oil CEOs aren’t worth the lives of the thousands of people who will die because of climate change.
Related posts
- 25 myths and bad arguments about climate change
- Basics of Global Climate Change: A Logical Proof That it is Our Fault
- Global warming hasn’t paused
- Global warming isn’t natural, and here’s how we know
- Yes, there is a strong consensus on climate change
Literature cited
- Alexander et al. 2006. Global observed changes in daily climate extremes of temperature and precipitation. Atmospheres 111:D05109.
- Allan and Soden. 2008. Atmospheric warming and the amplification of precipitation extremes. Science 321:1481–1484.
- Argaud et al. 2007. Short- and Long-term Outcomes of Heatstroke Following the 2003 Heat Wave in Lyon, France. Archives of Internal Medicine 167:2177–2183.
- Carnicer et al. 2010. Widespread crown condition decline, food web disruption, and amplified tree mortality with increased climate change-type drought. PNAS
- Dai 2010. Drought under global warming: a review. Cliamte Change 2:45–65
- Dai 2012. Increasing drought under global warming in observations and models. Nature Climate Change 3:52–58.
- Dai and Trenberth 1998. Global variations in droughts and wet spells: 1900–1995. Geophysical Research Letters 25:3367–3370.
- Della-Marta et al. 2007. Doubled length of Western European summer heat waves since 1880. Atmospheres 112:D15103.
- Elsner et al. 2008. The increasing intensity of the strongest tropical cyclones. Nature 455:92–95.
- Emanuel 2005. Increasing destructiveness of tropical cyclones over the past 30 years. Nature 436:686–688.
- Flannigan et al. 2009. Implications of changing climate for global wildland fire. International Journal of Wildland Fire 18:483–507.
- Groisman et al. 2005. Trends in intense precipitation in the climate record. Journal of Climate 18:1326–1350.
- Habeeb et al. 2015. Rising heat wave trends in large US cities. Natural Hazards 46:1651–1655.
- Hall and Kossin 2019. Hurricane stalling along the North American coast and implications for rainfall. Climate and Atmospheric Science 2
- Held and Soden 2006. Robust response of the hydrological cycle to global warming. Journal of Climate 19:5686–5699.
- Holland and Bruyere 2014. Recent intense hurricane response to global climate change. Climate Dynamics 42:617–627.
- Kossin et al. 2014. The poleward migration of the location of tropical cyclone maximum intensity. Nature 509:349–352.
- Kossin 2018. A global slowdown of tropical-cyclone translation speed. Nature Letters 558: 104-108.
- Klein Tank and Konnen 2003. Trends in indices of daily temperature and precipitation extremes in Europe, 1946–99. Journal of Climate 16:3665–3680.
- Lelieveld et al. 2016. Strongly increasing heat extremes in the Middle East and North Africa (MENA) in the 21st century. Climate Change 137:245–260.
- Luber et al. 2008. Climate change and extreme heat events. 35:429–435.
- Meehl et al. 2004. More intense, more frequent, and longer lasting heat waves in the 21st century. Science 305:994–997.
- Milly et al. 2002. Increasing risk of great floods in climate change. Nature 415:514–517.
- Min et al. 2011. Human contribution to more-intense precipitation extremes. Nature 470:378–381.
- Perkins et al. 2012. Increasing frequency, intensity and duration of observed global heatwaves and warm spells. Geophysical Research Letters 39:L20714.
- Robine et al. 2008. Death toll exceeded 70,000 in Europe during the summer of 2003. Epidemiology 331:171–181.
- Rosenzweig et al. 2001. Climate change and extreme weather events – Implications for food production, plat diseases, and pests. Global Change and Human Health 2:90–104.
- Russo et al. 2014. Magnitude of extreme heat waves in present climate and their projection in a warming world Atmospheres 119:12500–12512.
- Schar et al. 2004. The role of increasing temperature variability in European summer
- heatwaves. Nature 427:332–336.
- Schlenker and Lobell. Robust negative impacts of climate change on African agriculture. Environmental Research Letters 5:1–8.
- Stott et al. 2004. Human contribution to the European heatwave of 2003. Nature 432:610–614.
- Tanarhte et al. 2015. Heat wave characteristics in the eastern Mediterranean and middle East using extreme value theory. Climate Research 63:99–113.
- Trenberth 2011. Changes in precipitation with climate change. Climate Research 47: 123–138.
- Walsh et al. 2015. Tropical cyclones and climate change. Climate Change 7:65–89.
The Logic of Science 
Excellent post.
Two typos: 1- with all of the in mind. “these”? 2- from away from
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fixed, thanks
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Kudos on a very informative and timely article. Also see…
https://blogs.ei.columbia.edu/2018/09/12/hurricane-florence-resources-journalists/
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If extreme weather events are getting worse, then why aren’t more people dying from them? The statistics here http://www.nws.noaa.gov/om/hazstats/resources/weather_fatalities.pdf show a rather flat trend for weather-related deaths, which doesn’t make sense since we know temperatures are getting more extreme. Do you have any ideas why this is happening?
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It’s hard to know for sure without knowing more about that dataset and how it was collected, but I suspect that several things are happening.
First, improved technologies can help, especially with increases in means. So when looking at something like this, you have to take into account increased use of ACs, improved medical technologies, improved first response plans, etc.
Second, because extreme events are the real killers (and are harder to battle with improved technologies), you don’t neccissarily expect a liner trend. Rather, you expect an increasing number of spikes. For example, in that data set you see a massive spike in hurricane deaths in 2005. I suspect that this data set is only for the continental 48 US states, and that is the general cause of the shortage of spikes. If you expand that out to the entire world, the situation would be quite different, because it would also include 3000 people in Puerto Rico last year, 70,000 people in Europe in 2003, etc. To put that another way, even though extremes are increasing, they are still extremes. So you don’t expect many of them in any one area. Therefore, to actually see trends, you often have to look at the larger data set.
There are, of course, other factors that need to be taken into account such as increasing population size and other related variables. So I think the situation is really more complicated than a simple chart like that can capture.
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Thanks for this post.
One small error: there is a place that you say ” if we don’t action”; this should probably say “if we don’t act” or “if we don’t take action”.
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Fixed it, thanks
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In the current post you wrote: “I’d also like to briefly state that the evidence is extremely clear that we are the primary cause of the current warming. Discussing that evidence is beyond the scope of this post, but I have previously done so here [https://thelogicofscience.com/2016/06/06/global-warming-isnt-natural-and-heres-how-we-know/] and here [https://thelogicofscience.com/2015/01/30/basics-of-global-climate-change-a-logical-proof-that-it-is-our-fault/], as well as debunking most of the common arguments to the contrary here [https://thelogicofscience.com/2016/10/17/25-myths-and-bad-arguments-about-climate-change/]. Please read those posts before commenting with an argument that it’s not our fault.”
I read your “Comment Rules,” which state among other things: “Second, please stay on topic. If your comments are not relevant to the specific topic discussed in the post, the [sic] will be ignored or deleted.”
Since in the current post (a) you identify previous posts you have written and ask us to read those posts before commenting on the current post, and (b) in part you cite those posts as proof that your current post is valid, I’m going to assume that although from your perspective “Discussing that evidence [the evidence of the referenced posts] is beyond the scope of your current post,” from a commenter’s perspective, discussing the contents of your referenced posts is not beyond the scope of comments to this, the current, post. After all, if you call out specific references and you ask people to read those references before commenting on this post, aren’t the contents of those references fair game for comments on his post?
In one of your cited references (Global warming isn’t natural, and here’s how we know), you wrote: “A final major driver of climate change is, in fact, CO2. Let’s get a couple of things straight right at the start. First, we know that CO2 traps heat and we know that increasing the amount of CO2 in an environment will result in the temperature increasing (you can find a nice list of papers on the heat trapping abilities of CO2 here [https://agwobserver.wordpress.com/2009/09/25/papers-on-laboratory-measurements-of-co2-absorption-properties/]).”
Your sentence “First, we know that CO2 traps heat and we know that increasing the amount of CO2 in an environment will result in the temperature increasing…” contains two declarative statements: (1) “we know CO2 traps heat”, and (2) “we know that increasing the amount of CO2 in an environment will result in the temperature increasing…”. From a logic perspective, the two statements may be completely unrelated—like saying we know the sky is blue and we know the sky has a density less than that of water. But if your statement “that increasing the amount of CO2 in an environment will result in the temperature increasing” is completely separate from and unrelated to your statement that “CO2 traps heat,” then (a) why even mention the heat-trapping nature of CO2 gas at all, and (b) why provide an extensive list of references characterizing the electromagnetic spectral absorption properties of CO2 gas? In my opinion, if your statement “that increasing the amount of CO2 in an environment will result in the temperature increasing” is true, by itself that statement is sufficient for the purposes of your current post. Therefore, I believe it is fair to assume that in your mind the two statements (the heat-trapping nature of CO2 gas and a temperature increase of the Earth) are related—i.e., it is the heat-trapping nature of CO2 gas that is the reason CO2 gas in the earth’s atmosphere leads to increasing Earth temperature. If my belief is invalid (i.e., if you believe the heat-trapping nature of CO2 is completely separate from and unrelated to the claim that CO2 in an environment will result in the temperature increasing), then a statement from you to that effect warrants an apology from me and I freely give you that apology.
If my belief that the heat-trapping nature of CO2 plays a critical role in your claim that the presence of CO2 gas in an environment produces a temperature increase, then your readers would benefit from a definition, or at a minimum a fuller discussion, of what you mean by a “heat-trapping gas.” For example, what property or properties, if any, does a heat-trapping gas possess that a non-heat-trapping gas lacks; and what property or properties, if any, does a non-heat-trapping gas possess that a heat-trapping gas lacks? And if the two gases share a common set of properties, what property or properties are quantifiably different between the two kinds of gases, and what are the threshold values of those quantifiable differences that distinguish a heat-trapping gas from a non-heat-trapping gas?
Based on your extensive reference list supporting the contention that CO2 is a heat-trapping gas (https://agwobserver.wordpress.com/2009/09/25/papers-on-laboratory-measurements-of-co2-absorption-properties/) cited in one of your posts, I infer that the primary relevant property (if not the only property) that separates a heat-trapping gas from a non-heat-trapping gas is the property of a heat-trapping gas (which is lacking in a non-heat-trapping gas) to absorb electromagnetic radiation in sub-bands of the IR band. Furthermore, and in conjunction with the above, I infer that it is the atmospheric CO2 gas property of Earth-surface-emitted sub-band IR absorption that causes the Earth’s temperature to rise.
All else being equal, surrounding an active object (an active object is an object possessing an internal source of thermal energy) with inactive material (inactive material is material devoid of an internal source of thermal energy) that absorbs all radiation (not just IR sub-band radiation) emitted from the surface of the active object does not guarantee that the temperature of the active object will increase. In fact situations exist where the active object temperature is lowered in the presence of surrounding heat-trapping material. Thus, although (a) it may be true that relative to a designated starting time, the temperature of the Earth is increasing, and (b) atmospheric CO2 may play a measurable role in that temperature increase, it does not follow that because atmospheric CO2 absorbs IR sub-band electromagnetic energy emitted from the surface of the Earth, the presence of CO2 in the Earth’s atmosphere guarantees an Earth temperature increase. Thus to claim that because CO2 is a heat-trapping gas (i.e., absorbs radiation in sub-bands of the IR band) its presence in the Earth’s atmosphere will (must) result in an increase in the Earth’s temperature is simply wrong. If by experiment you want to show that atmospheric CO2 will (must) increase the Earth’s temperature, then controlled laboratory experiments on small systems are insufficient. You must perform a controlled experiment on a planet-like environment similar to the Earth. Since such a controlled experiment is in a practical sense impossible, you cannot from the outcomes of any number of controlled laboratory experiments conclude that an atmospheric heat-trapping gas will increase the Earth’s temperature.
Of course a heat-trapping gas can be defined to be “(all else being equal) any gas whose presence in the Earth’s atmosphere produces an increased Earth temperature relative to the Earth temperature with an atmosphere devoid of the gas.” But using that definition, the fact that a gas absorbs electromagnetic radiation in sub-bands of the IR band does not establish the heat-trapping nature of the gas. Using that definition, the only way to establish that CO2 is a heat-trapping gas is to show (either by experiment or by a complete theoretical treatment) that CO2 gas in the Earth’s atmosphere will, in fact, increase the Earth’s temperature.
The references you cite in your current post in turn reference papers that (a) discuss the IR sub-band absorption nature of CO2 gas, which as I have noted, in your mind is a necessary and sufficient condition to characterize CO2 as a heat-trapping gas, and (b) describe laboratory experiments where the presence of CO2 gas surrounding an active object increases the temperature of the object. Thus at a minimum, these papers establish that it is possible that the presence of CO2 gas in the Earth’s atmosphere will increase the Earth’s temperature. Other laboratory experiments, however, show that the presence of CO2 gas surrounding an active object possessing a constant-rate heat source lowers, not increases, the temperature of the active object. I described one such experiment in a comment to your “https://thelogicofscience.com/2018/07/19/6-major-problems-with-a-flat-earth/” post. Below I describe another laboratory-amenable situation where everything else being equal, the presence of an inactive heat-trapping substance surrounding an active object with a constant-rate heat source results in a temperature decrease of the active object relative to the active object’s temperature in the absence of the heat-trapping substance. If the referenced experiment and the described situation are valid, then they establish that the heat-trapping nature of a substance by itself does not guarantee that the presence of a heat-trapping substance surrounding an active object will increase the temperature of the active object. As such, the heat-trapping nature of CO2 gas cannot, by itself, be used to “prove” that atmospheric CO2 will increase the temperature of the Earth.
Consider a solid sphere of radius 0.1 meters. Assume the surface of the solid sphere behaves like a black body [i.e., the surface of the solid sphere (a) absorbs all electromagnetic energy incident on it, and (b) radiates electromagnetic energy in accordance with Planck’s Black Body Radiation Law]. Just below the surface of the solid sphere uniformly distribute a thermal energy source (maybe radioactive material) with a constant thermal energy rate output of 60 Watts. Locate the solid sphere either in the vacuum of cold space far removed from all other mass or in a laboratory environment where the solid sphere exists in a vacuum and is completely surrounded by a “wall” at a temperature near the temperature of liquid helium. Let the sphere come to energy-rate-equilibrium (ERE). ERE is the state such that the rate energy enters a system equals the rate energy leaves the system. Since the rate energy enters the solid sphere is 60 Watts and energy can leave the isolated solid sphere only via thermal radiation from its surface (which for the solid sphere acts like a black body), according to the Stefan-Boltzmann Law, which is derivable from Planck’s Black Body Radiation Law, the ERE temperature of the solid sphere in isolation will be approximately 302.923 Kelvin.
Now surround the solid sphere with an inactive, concentric, thin, electromagnetic-energy-absorbing, shell whose inside and outside surfaces behave like a black body. Since the shell absorbs ALL electromagnetic radiation emitted from the surface of the solid sphere, the shell qualifies as a heat-trapping substance in that it absorbs electromagnetic energy in sub-bands of the IR band. The outer radius of the shell is 0.2 meters and the thickness of the shell is so small that for all practical purposes the inner radius of the shell is also 0.2 meters. When coupled with the thin nature of the shell, the thermal conduction property of the material comprising the shell is such that for all practical purposes the temperature of the shell’s inner surface will be the same as the temperature of the shell’s outer surface. Wait for the solid-sphere/shell system to come to ERE. Energy can leave the solid-sphere/shell system only via thermal radiation from the outer surface of the shell. Since energy enters the solid-sphere/shell system only via the solid-sphere’s internal source of energy (60 Watts), in ERE 60 Watts must be radiated from the outer surface of the shell. Given that the outer surface of the shell acts like a black body radiator with a surface area of 0.502655 square meters, in ERE the temperature the outer (and inner) surface of the shell will everywhere be approximately 214.199 Kelvin.
The law of radiative cooling says that for a black body object having a surface area “A” surrounded by a wall at temperature T0, the rate of object cooling (i.e., the net rate thermal energy leaves/enters the object) is sigma (the Stefan-Boltzmann constant) …times… “A” …times… the difference between (a) the temperature (TBB in Kelvin) of the black body’s surface to the fourth power and (b) the temperature (T0 in Kelvin) of the surrounding wall to the fourth power. For the situation being discussed, in ERE (a) the solid sphere must cool at a rate of 60 Watts, (b) T0 is 214.199 Kelvin, and (c) the surface temperature, TBB, of the solid sphere will be approximately 320.302 Kelvin. The temperature 320.302 Kelvin is greater than the temperature 302.923 Kelvin so in this case surrounding the active solid sphere with the heat-trapping shell produces an increased solid sphere temperature.
Now connect the solid sphere to the shell with six, inactive, uniformly-distributed, radially oriented, cylindrical rods having a radius of 0.002582 meters and a thermal conductivity of 401 Watts per meter per Kelvin (the thermal conductivity of copper). The rods support the conductive transfer of thermal energy from the solid sphere to the shell. The six rods decrease the radiative surface area of the solid sphere by approximately 0.000125665 square meters, which is a small fraction of the solid sphere’s surface area of 0.125664 square meters. This means that even in the presence of the six connecting rods, the solid sphere still contains a large surface area from which electromagnetic energy can and will be radiated and will be “trapped” by the shell and/or by the connecting rods. Thus, although the connecting rods may have a significant effect on the rate energy is radiated from the surface of the solid sphere, that effect will be due almost exclusively to a change in solid sphere surface temperature and not to a change in solid sphere surface radiation area.
Note that provided the presence of the connecting rods has negligible effect on the uniform-temperature nature of the outer surface of the shell, the presence of the connecting rods will have no effect on the ERE temperature of the shell’s outer surface. To radiate energy at 60 Watts (the ERE condition), the temperature of the outer surface of the shell must be 214.199 Kelvin just as it was in the absence of the connecting rods. However, the presence of the connecting rods will have significant effect on the ERE temperature of the surface of the solid sphere. This is because the connecting rods provide a conductive (non-radiative) path for the transfer of thermal energy from the solid sphere to the shell, where the conductive path of thermal energy transfer obeys a linear-temperature-difference rule rather than a temperature-to-the-fourth-power-difference rule. For the situation described above, the ERE temperature of the solid sphere surface with the six connecting rods cannot exceed approximately 281.362 Kelvin, which is less than the surface temperature, 302.923 Kelvin, of the solid sphere in isolation. Thus a situation exists where surrounding a constant-energy-rate active solid sphere with inactive heat-trapping material produces a lower, not higher, active sphere surface temperature.
I now demonstrate that for the conditions described above, the surface temperature of the active solid sphere in the presence of the surrounding heat-trapping shell and connecting rods cannot exceed 281.362 Kelvin. I start by computing the heat current through the six connecting rods.
For a uniform cross-sectional-area thermally conductive barrier (in our case, the thermally conductive barrier is a connecting rod) having a cross sectional area of (0.0000209441 square meters), Newton’s Law of thermal conduction says that the heat current through each connecting rod is directly proportional to (a) the cross section area of the rod (0.0000209441 square meters) and (b) the temperature difference between the two ends of the connecting rod (281.362 minus 214.199 equals 67.163 Kelvin), and inversely proportional to the length of the rod (0.1 meters). The proportionality constant is the thermal conductivity, “k” of the rod (401 Watts per meter per Kelvin). For the temperatures, dimensions, and thermal conductivity given above, the heat current through each connecting rod is approximately 5.6407 Watts, and the heat current through all six connecting rods is approximately 33.844 Watts.
I next compute the rate radiative energy leaves the solid sphere. For the conditions of this example, the Stefan-Boltzmann Law, which can be derived from Planck’s Black Body Radiation Law, can be used to compute the rate radiative energy leaves the solid sphere. The Stefan-Boltzmann Law says the rate energy is radiated from a black body surface at temperature “T” (Kelvin) and surface area “A” is directly proportional to the product of “A” and the temperature T to the fourth power, where the proportionality constant is the Stefan-Boltzmann Constant (0.00000005670373 Watts per square meter per Kelvin to the fourth power). In our case, the solid sphere has a radiating area “A” equal to the surface area of the solid sphere less the cross sectional area of the six connecting rods. Thus, in our case where “A” is approximately 0.125538 square meters and T is 281.362 Kelvin, the rate energy is radiated away from the solid sphere is approximately 44.612 Watts. Combining these two rates, the total rate (radiation and conduction) energy leaves the solid sphere is approximately 78.456 Watts.
The rate energy enters the solid sphere is the sum of (a) the solid sphere’s internal thermal energy rate (60 Watts), (b) the rate radiated energy from the inner surface of the shell is incident on and absorbed by the solid sphere, and (c) the rate radiated energy from the walls of the six cylinders is incident on and absorbed by the solid sphere.
Consider a planar differential surface area at temperature T (Kelvin) and a sphere of radius RS whose center is located a distance R>RS away from the planar differential surface area on the line passing through the “center” of and perpendicular to the planar differential surface area. Some of the radiation emitted from the planar differential surface area will be directed towards and strike the surface of the sphere; and some of the radiation emitted from the planar differential surface area will be directed away from and miss the surface of the sphere. If the planar differential surface area radiates like a black body, then the ratio of the energy striking the sphere to the total energy radiated by one side of the planar differential surface area is equal to the ratio of RS squared to R squared. For our example of a concentric solid sphere and shell, the value of RS is 0.1 meters and the value of R is 0.2 meters. For these values, one quarter of the energy radiated by one side of the planar differential surface area will strike the solid sphere. Since the surface of the solid sphere acts like a black body, all of the energy incident on the solid sphere will be absorbed by the solid sphere.
Now for the geometry of a solid sphere of radius 0.1 meters and a thin concentric spherical shell of radius 0.2 meters where the inner surface of the spherical shell is the black body radiating surface, all differential surface areas on the inner surface of the shell satisfy the conditions that (a) the solid sphere’s center is a distance of 0.2 meters from the differential surface area, and (b) the solid sphere’s center is on the perpendicular “bisector” of the differential surface area. Since the ratio of the energy from each differential surface area directed towards the solid sphere is one quarter of the energy radiated by the differential surface area, the ratio of the total energy radiated from the inner surface of the shell towards the solid sphere is one quarter of the total energy radiated from the inner surface of the shell. Now the six connecting rods cover a portion of the inner surface of the shell. Thus, in the presence of the six connecting rods, the available radiating surface area of the inner shell is slightly reduced. For our example, the reduced area is approximately 0.00012567 square meters relative to a total inner shell surface area of approximately 0.502655 square meters. Thus, in the presence of the connecting rods, the available radiating area on the inner surface of the shell is 0.502529 square meters. This means that in the presence of the connecting rods, (a) the inner surface of the shell at a temperature of 214.199 Kelvin radiates energy at a rate of approximately 59.985 Watts, and (b) one quarter of this radiated energy (a rate of 14.996 Watts) is radiated in the direction of the solid sphere. Using the approximation that none of the energy radiated from the inner surface of the shell is absorbed by the connecting rods, the rate energy from the inner surface of the shell is incident on and absorbed by the solid sphere is approximately 14.996 Watts.
Note that because some of the energy radiated from the inner surface of the shell is incident on and absorbed by the connecting rods, the value of 14.996 Watts is greater than the actual solid sphere absorbed energy from the shell’s inner surface; and thus using 14.996 Watts will result in an overestimation of the energy entering the solid sphere which in turn will result in an over estimation of the temperature of the surface of the solid sphere.
Using worst case assumptions (which are not valid, but which produce the highest solid sphere surface temperature) that (a) the temperature of the cylindrical surface of each connecting rod is everywhere the same as the temperature of the solid sphere surface, and (b) all of the radiation emitted from the cylindrical surfaces of the six connecting rods is directed towards and absorbed by the surface of the solid sphere, the rate radiative energy from the six connecting rods is absorbed by the solid sphere is approximately 3.460 Watts. [Note: As with the surface of the solid sphere and both surfaces of the shell, we assume the cylindrical surfaces of the connecting rods behave like black body surfaces.]
In actuality the surface temperature of the rods decreases with distance from the solid sphere so that assuming a uniform rod temperature equal to the temperature of the solid sphere overestimates the actual rate of solid sphere energy absorption. In addition, some of the radiation emitted from the cylindrical surface of the rods will be directed towards and absorbed by both “other rods” and the inner surface of the shell. Thus assuming all of the radiation emitted from the rods is absorbed by the solid sphere, also overestimates the actual rate of solid sphere energy absorption from the connecting rods. Overestimating the rate the solid sphere absorbs radiated energy produces an ERE temperature higher than the actual ERE temperature.
Bottom line, for an active solid sphere surface temperature of 281.362 Kelvin, the maximum rate energy enters the active solid sphere is approximately 60 + 14.996 + 3.460 = 78.456 Watts and the rate energy leaves the active solid sphere is approximately 78.456 Watts. Thus the ERE temperature of 281.362 Kelvin represents the maximum rate energy can enter the solid sphere and generates a solid sphere ERE surface temperature higher than the actual solid sphere ERE surface temperature. Since the maximum possible temperature of the surface of the solid sphere is lower than the solid sphere surface temperature in isolation, we have a situation where the presence of heat-trapping material surrounding an active object with a constant-rate internal source of thermal energy decreases the surface temperature of the active object.
Now any number of valid statements can be made to the effect that an active solid sphere connected via thermally-conducting rods to a surrounding inactive heat-trapping shell does NOT represent the condition of an Earth with CO2 gas in the Earth’s atmosphere. These statements will not, however, negate the point that everything else being equal, inactive heat-trapping material surrounding an active object may or may not increase the temperature of the active object. Thus, BY ITSELF the fact that CO2 is a heat-trapping gas cannot be used to prove that atmospheric CO2 will increase the Earth’s temperature. Atmospheric CO2 gas may increase the Earth’s temperature; but to so demonstrate requires either (a) a planetary-like controlled experiment, or (b) a theoretical analysis that takes into account more than the condition that “CO2 is a heat-trapping gas.”
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A). This is extremely off topic, so I’m not going to discuss it beyond this comment. I specifically said that it was beyond the scope of this post (i.e., off topic) and your mental gymnastics to convince you that it is on topic are truly baffling (indeed, the entire point of directing people to my previous articles about CO2 was precisely to avoid having to have this type of conversation on this post).
B). My previous discussions with you have demonstrated that having such discussions with you is pointless, and I simply don’t have the time, patience, or energy to go over all of this with you again.
C). As I explained at length previously, your previous example did not demonstrate that CO2 is not a heat trapping material. Rather, it simply demonstrated that a vacuum is a good insulator due to a lack of convection.
D). By your own admission, your example in this thread is extremely, extremely different from CO2. It is different to the point of irrelevance. As you seem to have acknowledged, we know from countless experiments that if you increase the concentration of CO2 in a container, that container will trap more heat than an identical container with lower CO2 concentrations. There is absolutely no reason to think that this doesn’t scale up to the atmosphere, and your example does nothing to change that.
E). You are ignoring the studies of past climate that have demonstrated that CO2 concentrations are a major driver of the earth’s climate.
F). You are ignoring the satellite studies that have directly measured our CO2 in the atmosphere trapping increased amounts of IR. Nothing that you have said changes the results of those studies.
For anyone who is curious, you can read the previous debates between Reed and I in the comments of this post https://thelogicofscience.com/2018/07/19/6-major-problems-with-a-flat-earth/
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“… because it is very easy to fall victim to the same logical blunder that often ensnares climate change deniers: confusing weather with climate.”
Perhaps IPCC scientist and director of the Australian National University’s Climate Change Institute, Prof. Will Steffen will be interested to know he is now a “climate change denier” …
“A few years ago, talking about weather and climate change in the same breath was a cardinal sin for scientists.
Now it has become impossible to have a conversation about the weather without discussing wider climate trends, according to researchers who prepared the Australian Climate Commission’s latest report.
Previously, ”weather is not climate” was the mantra, but now the additional boost from greenhouse gases was influencing every event.
It might even be the case that the mantra chanted after every catastrophic weather event – that it can’t be said to be caused by climate change, but it shows what climate change will do – has become a thing of the past.”
https://www.theage.com.au/national/climate-change-a-key-factor-in-extreme-weather-experts-say-20130303-2fefv.html
Worst Apocalypse. Ever.
Undeniably.
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