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Physics v. climate prevarication

We have witnessed the consequences of ignoring three significant warnings this century; 9/11, the 2008 Financial Crisis and the pandemic and now are countenancing the discounting of climate change.

Instead of observing the science, we are falling for the technologies and politics of prevarication.

Global warming is a problem of thermodynamics. The second law of which says heat flows from warm to cold and never the reverse.

The following schematic of the Pacific Ocean from the equator to the North Pole, the greatest repository of the heat of warming, shows the heat of warming delineated in degrees Celsius where red is hot, dark blue is cold, gray is land and white is the polar icecap.


Figure 1

The latitudinal scale of Figure 1 is 10,000 greater than the 600-meter depth of the ocean shown in the schematic.

The movement of heat from the surface into deep water is facilitated by the trade winds which blow heat from east to the west and pile water up to the extent shown in Figure 2 where the Pacific Ocean is close to 30 centimeters higher on the western side than the eastern side of the ocean.

Figure 2

The second law of thermodynamics also states, regarding using heat transfer to do work, it is impossible in any system for heat transfer from a reservoir to completely convert to work in a cyclical process in which the system returns to its initial state.

The following schematic shows how this embodiment of the second law relates to the Pacific Ocean and the potential of the ocean to produce work given the latitudinal scale is 6,000 times greater than the depth of the ocean which reaches a depth of 1,000 meters in this example.


Figure 3

 The hot source as represented by the red band of the tropics is the only segment of the heat of global warming capable of producing work, which requires a temperature differential of a least 18oC between the surface and the cold sink to be serviceable.

According to the National Oceanic and Atmospheric Administration, between 1993–2018 the full-depth of the ocean gained between 0.57 to 0.81 watts per square meter of heat and since the surface area of the ocean is 360 million square kilometers, this translates to between 194.4 and 291.6 terawatts of heat, which although being stored will eventually be released, committing Earth to additional warming in the future.

The efficiency of the conversion of the heat of warming to work is the relationship 1- (QH-QC)/QH)  from  Figure 1 or 1-(303-277)/303 or 8.6% so, the heat of warming can produce between 16.7 and 25.1 terawatts of work initially and the balance can be converted at a latter time.

This analogy is both broken down and reinforced by the buoyancy shown in Figure 3 and by the heat pipe in Figure 4, which moves heat from a hot source to a cold sink through the phase changes of a working fluid.

Figure 4

Figure 5

Global warming heats surface water in the tropics, but not sufficiently to produce a vapor pressure capable of moving the heat of warming into deep water. As a result, the warmed water is buoyant, and has as its only avenue of escape the poles.  

A heat pipe, however, draws heat from the surface into a low-boiling-point working fluid, like ammonia, to produce a vapor pressure that moves the heat into the vacuum of a condenser where the vapor condenses and releases the heat of global warming into the cold sink of the ocean. The residual heat of warming not converted in Figure3 warms the cold water, giving it buoyancy so the warmed water resurfaces where it can be recycled.    

This is the technically sound way of addressing global warming as opposed to the technologies of prevarication identified by Duncan McLaren & Nils Markusson in their paper The co-evolution of technological promises, modelling, policies and climate change targets where the authors note, “The nature and framing of climate targets in international politics has changed substantially since their early expressions in the 1980s. Here, we describe their evolution in five phases—from ‘climate stabilization’ to specific ‘temperature outcomes’— co-evolving with wider climate politics and policy, modelling methods and scenarios, and technological promises (from nuclear power to carbon removal). We argue that this co-evolution has enabled policy prevarication, leaving mitigation poorly delivered, yet the technological promises often remain buried in the models used to inform policy. We conclude with a call to recognize and break this pattern to unleash more effective and just climate policy."

The five phases of evolution and their definitions are:

The contemporary technological proposals for responding to climate change identified by  McLaren and Markusson include nuclear fusion, giant carbon sucking machines, ice-restoration using millions of wind-powered pumps, and spraying particulates in the stratosphere.

Critically, they say,  “in this process, each technological promise has  enabled  a  continued  politics  of  prevarication  and  inadequate  action  by  raising  expectations  of  more  effective  policy  options  becoming available in the future, in turn justifying existing limited and  gradualist  policy  choices  and  thus  diminishing  the  perceived  urgency  of  deploying  costly  and  unpopular,  but  better  understood  and tested, options for policy in the short term. The prevarication they identify isn’t necessarily intentional, but feeds on systemic 'moral corruption', in which current elites are enabled to pursue self-serving pathways, while passing off risk onto vulnerable people in the future and in the global South.”

The article describes a history of such promises, showing how the overarching international goal of 'avoiding dangerous climate change' has been reinterpreted and differently represented in the light of new modelling methods, scenarios and technological promises.

The targets, models and technologies have co-evolved in ways that enable delay: "Each novel promise not only competes with existing ideas but also downplays any sense of urgency, enabling the repeated deferral of political deadlines for climate action and undermining societal commitment to meaningful responses,” they say. And conclude: "Putting our hopes in yet more new technologies is unwise. Instead, cultural, social and political transformation is essential to enable widespread deployment of both behavioral and technological responses to climate change."

And  McLaren and Markusson aren’t alone in their call for more effective and just climate policy.

In the paper, Decision making in contexts of deep uncertainty – an alternative approach for long-term climate policy by Workman et al., show  that the IAMs McLaren and Markusson referenced have been developed within a very small, narrow community and can heavily distort decision-making processes. For example, large-scale Carbon Dioxide Removal (CDR) is one such distortion that is problematic for a number of reasons. Most worrying, dependence on CDR is being baked into international emissions targets without public debate, which is likely to lead to polarization as a function of the trade-offs and side-effects of large-scale CDR deployment and is likely to hinder progress on CDR and alternative mitigation strategies.

Workman says, “One of the most high profile distortions in climate policy development has been that the majority of global emissions scenarios compatible with holding global warming to less than 2°C depend on the large-scale use of BECCS of up to 15 billion tons pa – to compensate for an overshoot of atmospheric CO2 concentrations. Recent critiques have highlighted the ethical and environmental risks of this strategy – The scale of carbon removal deployment would rival the worlds’ largest industries and sectors such as Oil and Gas and Agriculture. At present less than a few thousand tonnes of carbon dioxide are removed annually.”

The authors argue “the tendency to view model outputs as objective science, capable of defining “optimal” goals and strategies for which climate policy should strive, rather than as exploratory tools within a broader policy development process. Effectively, a model-centric decision-making philosophy is highly sensitive to uncertainties in model assumptions and future trends and tends to favour solutions that perform well within a narrow-modelled framework at the expense of exploring a wide and diverse mix of strategies and values.”

And that “the need for an alternative approach that explicitly embraces uncertainty, multiple values and diversity among stakeholders and viewpoints, and in which modelling exists in an iterative exchange with policy development rather than separate from it. Such an approach would provide more relevant and robust information to near-term policy-making and enable appropriate goals for climate policy in a given context being agreed and defined by dialogue between multiple stakeholders rather than based on forecasts rather than actual results of a single community.”

In the contemporary lexicon, going 'viral' means a piece of news, image or video that has become incredibly popular on social media in a short time.

A viral solution that can be rapidly absorbed and acted on by the masses is required to address global warming but instead élites, in recent months bolstered by the virus that is wiping out their nascent competition, are crushing the environmental wants and needs of society.

The only antidote to this rout are the laws of physics dealing with heat, temperature, and their relation to energy, work, radiation, and the properties of matter.

 

Discussions

Bob Meinetz's picture
Bob Meinetz on May 8, 2020

Jim, though I understand (and agree with) the point you're trying to make, you're still confusing energy with rate of energy transfer. For example, you write

"According to the National Oceanic and Atmospheric Administration, between 1993–2018 the full-depth of the ocean gained between 0.57 to 0.81 watts per square meter of heat..."

That's not what NOAA is saying, however. They say

"Averaged over the full depth of the ocean, the 1993–2018 heat-gain rates are 0.57-0.81 watts per square meter."

The difference between "heat" (energy, measured in watthours or joules) and "heat-gain rate" (power, measured in watts) is significant. To calculate the amount of heat the ocean has accumulated from 1993-2018 we take the number of hours during that period (227,904), multiply by the average rate at which heat accumulated, then multiply by the surface area of the ocean, in m^2. This gives us the amount of heat (or energy, or work, all the same thing) the ocean has accumulated during that period.

If we take the ocean heat anomaly as shown on NOAA's chart (~18e+22 joules), convert to terawatthours (50e+6 TWh), then divide by the number of hours between 1993-2018, we get a number representing a rate of energy transfer, 219.4 TW, very close to the one you came up with (between 194.4 and 291.6 TW).

So what's the diff? You incorrectly assume "between 194.4 and 291.6 TW" represents heat, but neither figure represents heat. They represent the rate of heat transfer between 1993 and 2018 - how fast the ocean warmed. Maybe, energy from the ocean could not be taken out as fast as it went in. But maybe, with a significant investment in OTEC technology, it could be taken out faster - even fast enough to provide much of our future energy needs without creating any carbon emissions.

I hope you'll take the time to gain a better understanding of these concepts. Bringing physics into these discussions is always welcome, and I think you're on to something.

Jim Baird's picture
Jim Baird on May 9, 2020

Bob I am a backyard inventor rather than a power engineer, therefore it isn't surprising we look at things from a different perspective and I may well confuse energy with a rate of energy transfer but I am only interested in the bottom line, which Ralph Keeling points out in Realclimate yields a ΔOHC trend of 1.21 ± 0.72 x 1022 J/yr.

Kyle's converter converts this to  3361111.11 TWh, which is 384 terawatts/yr.

As to bringing in Physics, in his article, Ocean heat storage: a particularly lousy policy target, In Realclimate, Stefan Rahmstorf claims there are Two basic ocean physics facts, (i) heat content is an integral quantity and (ii) the response time of the ocean. And goes on to say, "Imagine you’ve recently turned on the stove. The heat content of the water in the pot will increase over time with a constant setting of the stove (note that zero emissions correspond to a constant setting – emitting more greenhouse gases turns up the heat). How much heat is in the water thus depends mainly on the past history (how long the stove has been on) rather than its current setting (i.e. on whether you’ve recently turned the element up a bit). That is why it is an integral quantity – it integrates the heating rate over time. You can tell from the units: heat content is measured in Joules, heating rate in Watts which is Joules per second, i.e. per unit of time.

The water in the pot heats up much faster than the global ocean. The water in the pot may be typically ~10 cm deep and heated at a rate of 1500 Watt or so from below. But the ocean is on average 3700 meters deep (thus has a huge heat capacity) and is heated at a low power input of the order of ~1 Watt per square meter of surface area. Also it is heated from above and not well mixed but highly stratified. Warm water floats on top, which hinders the penetration of heat into the ocean. Water in parts of the deep ocean has been there for more than a millennium since last exposed to the surface. Therefore it will take the ocean thousands of years to fully catch up with the surface warming we have already caused. That is why limiting ocean heat content to 1024 Joules is not possible even if we stop global warming right now – even though this amount is four times the amount of heating already caused since 1970. Ocean heat content simply does not respond on policy-relevant time scales."

I disagree completely and that this lack of foresight about how ocean heat can be manipulated with heat pipes is ensuring that the problems of global warming and energy aren't being solved. 

And to be fair to Dr. Rahmstorf, a number of other climate scientists have used the buoyancy argument to refute Figure 3 as well.  

 Thank you for your acknowledgment I might be onto something. 

I don't think though we want to take energy out of the ocean as fast as it went in. Particularly since, with negative emissions CO2 ocean thermal energy conversion, the current load of CO2 in the atmosphere could be drawdown in as little as 7 years. Absent the greenhouse effect the atmosphere would warm rapidly therefore I think we need to govern the release of the accumulate over thousands of years  by recyling the OHC. 

 

 

 

 

Bob Meinetz's picture
Bob Meinetz on May 11, 2020

"I may well confuse energy with a rate of energy transfer but I am only interested in the bottom line..."

The difference is the bottom line, and you're halfway there:

"That is why it is an integral quantity – it integrates the heating rate over time. You can tell from the units: heat content is measured in Joules, heating rate in Watts which is Joules per second, i.e. per unit of time."

Precisely. Think of heat in the ocean being analogous to water in a bucket: "3 TWh of heat content in the bottom of the ocean" is analogous to "3 gallons of water in the bucket".

Similarly: "At the rate of 3 TW (3 trillion joules/second), after one hour the ocean will have accumulated 3 TWh of heat content" is analogous to "Pouring water at the rate of 3 gallons/hour, after one hour the bucket will have accumulated 3 gallons of water."

From this I think you can see why 3361111.11 TWh is not the same as "384 terawatts/yr", but 384 TWy (terawattyears) - the product of terawatts and years, not its quotient.

The NOAA link you provided is fascinating, I had no idea 90% of energy retained by the Earth was in its oceans. That's as good a reason as any to look into OTEC as a possible source of energy. 50 million trillion watthours = 50 exawatthours = 50,000,000,000,000,000,000 watthours could power civilization for a long, long time.

Jim Baird's picture
Jim Baird on May 12, 2020

Marc & Richard Perez in there paper  A FUNDAMENTAL LOOK AT SUPPLY SIDE ENERGY RESERVES FOR THE PLANET show OTEC’s potential at 3-11 TWy/y, based on conventional OTEC, which is about half as efficient as heat pipe OTEC.

The physicist Melvin Prueitt, in his patent application US20070289303A1 Heat transfer for ocean thermal energy conversion, calculated the efficiency of heat pipe OTEC at 7.6%  when using ammonia as the working fluid. So, the heat of global warming is 384 TW, which can produce 29 TW of primary energy a year (1.56 times the world energy use in 2015}.

 Peres & Peres estimate the global energy demand will reach 27TWyr per annum in 2050, which can be provided by the recycling the heat of warming for (100/7.6 = 13.2) * 226 or the next 2983 years.

We won’t have this energy in 2050 if we don’t start building out the infrastructure today.

Peres show the Renewables in TWy/y.  A reviewer of a paper I published on the subject said TWy/y is redundant since the ys cancel out and wouldn’t publish the paper until I revised  TWy/y to TW.

Bob Meinetz's picture
Bob Meinetz on May 14, 2020

Jim, the reviewer is correct. Both "27 TWy/y" and "27 TWyr per annum" are very complicated ways to write "27 TW".

"So, the heat of global warming is 384 TW, which can produce 29 TW of primary energy a year (1.56 times the world energy use in 2015}."

This doesn't make sense. 384 TW is not a quantity of heat energy, but a rate of energy transfer. To find out how many TWh of energy will be transferred over a year's time, multiply by the number of hours in a year: 384 terawatts x 8,760 hours = 3,363,840 terrawatthours (TWh - the units multiply too).

Global primary energy consumption in 2015 was 149,634 TWh.
If we're assuming 384 TW is how fast energy is being absorbed from the sun into the Earth's oceans, one year's worth of sunlight could power all of humanity's needs for 22 years. But with 50,000,000 TWh of heat energy already stored in the ocean,  the tank is full now - there's already enough energy to power humanity for a long, long time.

If, that is, it can be converted to electricity, and if it can be distributed to where it's needed - two very big IFs.

I didn't see where Prueitt identified his low-boiling-point "working fluid", but using ammonia would be insanity. For many species of fish, ammonia is toxic at 1 mg/L. A spill of hundreds of tons of ammonia in the ocean would leave a lot of dead fish and a lot of explaining to do.

Jim Baird's picture
Jim Baird on May 14, 2020

The heat pipe as shown in Figure 5 is a closed system and ammonia is only one of the working fluids he studied, although it seems to be the most efficient. Although he didn't consider CO2 as the working fluid, others have. It would be far less toxic.

Jim Baird's picture

Thank Jim for the Post!

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