Ask me anything on Climate and Energy

[sayak83]

One of the arguments I often hear is how climate change was predicting catastrophic end-of-the-world scenarios that haven't come to fruition. But from my own education, it appears that many of the predictions have been occurring: droughts, severe weather, sea-level rise, etc.

What have climate change predictions gotten correct or incorrect, and what may still yet occur?

Quantitative predictions of extreme weather events is relatively new. So I could not yet find previous quantitative predictions that that match currently observed intensities. However, predictions of 1980-2000 climate models about future projected temperature rise has borne out very well with current observations. This can be seen here.

Study Confirms Climate Models are Getting Future Warming Projections Right – Climate Change: Vital Signs of the Planet

As we can see the observed post 2000 surface temperature closely track the ensemble mean of all pre-2000 climate models. This shows that the basic predictions even of very early models are robust.

Further recent studies have shown that, if we neglect climate change based forcing of the weather, we underpredict currently ongoing extreme weather events by about 50%. This roughly means that if climate change were not there, the number of extreme weather events (no. of heatwave days and no. of extreme rainfall days) would have been halved over the last decade.

Climate change means more extreme weather than predicted

 

[sayak83]

Are we in fact, already ****ed?

Climate change induced Weather will cause large scale damages to human society over the next 50-60 years, that is certain. But we can still decrease the intensity of such effects by going CO2 free as fast as possible. The more we delay, the worse it gets.

 

[sayak83]

Why such wide swings in climate
in past 10k years

10,000 years ago we moved into an interglacial period. So at that time there was climatic instabilities associated with the transition. But the climate stabilized after that.

 

[sayak83]

Been looking into this a lot, I have soooooo, many questions

1 - It seems we could make far better use of the fact that once you get about 4-6 feet underground, it's always around 54 degrees. Why aren't we making better use of that geothermal property to heat and cool our homes and greenhouses? Some people are doing it, why isn't it far more common?

Primarily because it is not cost-competitive with cheap fossil-based heat yet and you need to construct the buildings differently from the beginning to exploit this resource properly. It absolutely necessary to push this technology faster into the market. But rapid market growth is happening. Check out page 114 of the report below on the status of groud source heat pumps.
https://www.ren21.net/wp-content/uploads/2019/05/GSR2022_Full_Report.pdf

2 - What do you think our best non-battery storage technologies will be? Huge cookoo clock thingies? Sand batteries? compressed gasses?

Pumped hydro is and will remain the largest energy storage technology followed by batteries for grid applications. Sand batteries are basically thermal storage systems and may be useful where thermal energy needs to be stored (rocks and bricks are also used in many places for this). Calling it a battery is a misnomer as it can only store and release thermal energy, not electrical energy. The only thing I can see possibly competing with pumped hydro and battery for grid storage is maybe electrolysis based hydrogen...but for that a lot of the conversion and storage technologies need to improve.

3 - How's algae diesel coming along?

Still too slow and expensive conversion process. But researchers (including myself) are trying to improve the process. Basically, the challenge is to get the algae to produce enough lipids in its cells and then to extract these lipids efficiently by breaking the cell structure. Lipid to diesel conversion is relatively straightforward. Also we are trying to grow these algae on waste and saline water to avoid resource costs. Let's see how it goes.

4 - Why aren't we sinking HUNDREDS of BILLIONS of dollars into fusion research?

I think there are several research groups and lots of investment going on already. I am not an expert on the topic, but it seems there continues to be issues. I am not seeing anything commercial in that space till 2040 at least (probably 2050).
Science | AAAS
People do not realize how much solar PV and wind energy has benefitted from the silicon based electronics industry and the advances in polymer technologies in the materials industry to make the power production processes more efficient. Renewable grid would never have been possible without advances in computing and machine learning based optimization algorithms that were developed for other purposes. The problem I am seeing with fusion is that its material requirements are not needed anywhere else in our current industries...so it needs to do everything for itself. That is causing the slow speed of technology maturation.

 

[exchemist]

Nope for the CO2. It also binds to haemoglobin, the same as CO and O2. That's the way it gets out of the body, the same way the O2 got in.

That's not the case. Only 25% of CO2 is carried by haemoglobin, the majority being simply dissolved in the blood plasma, mostly as bicarbonate.

But you are partly right in that the 25% that is carried by haemoglobin does tend to reduce its affinity for oxygen, though it does not bind to the Fe atom in the way that O2 and CO do. CO2 forms an adduct with an amine group on haemoglobin. Both this and the lowering of pH by higher concentrations of dissolved CO2 favour the T conformation of haemoglobin, in which its oxygen affinity is reduced.

 

[Heyo]

Pumped hydro is and will remain the largest energy storage technology followed by batteries for grid applications. Sand batteries are basically thermal storage systems and may be useful where thermal energy needs to be stored (rocks and bricks are also used in many places for this). Calling it a battery is a misnomer as it can only store and release thermal energy, not electrical energy. The only thing I can see possibly competing with pumped hydro and battery for grid storage is maybe electrolysis based hydrogen...but for that a lot of the conversion and storage technologies need to improve.

There is also pressurised air, though that isn't tested enough, afaik. A depleted gas field near me was scheduled to be a test case but that got cancelled and the field is now used for gas storage. (We need that currently.)

 

[sayak83]

I am interested in how realistic it is now thought to be for hydrogen to play a role as an energy storage and transfer medium. I am thinking of two applications: motive power for trucks, and home heating (to replace piped natural gas).

I imagine a great depends on the prospects for more efficient large-scale electrolysis (though blue hydrogen could be a useful temporary source, to help hydrogen achieve scale quickly enough to get the truck and heating applications to take off commercially.)

What is the current thinking on this?

The problem with hydrogen currently is that the elctrolysis technology is still not as efficient as it should be and that the storage is big issue. Developing better electrolysis technologies and forms of physical and chemical storage is crucial for this to work in an economical manner. You can see the report below that shows that green hydrogen is still the costliest route to hydrogen production. That needs to change.
https://iea.blob.core.windows.net/a...-b499-7ca48e357561/The_Future_of_Hydrogen.pdf

Figure from the report shows that at least till 2030 hydrogen from grid electricity remains the costliest option. Hydrogen production in standalone renewable energy systems becomes reasonably cost competitive especially as a means of storing excess energy that the grid does not need. So hydrogen could become an alternative to battery based energy storage systems for a renewable energy generation plant (wind or solar). It is also important to understand, using electricity to generate hydrogen is only carbon neutral when the electricity comes from a renewable source. Otherwise it is not. For current world electricity mix, H2 production will have high CO2 costs. So hydrogen production must be done in concert with shifting of electricity to renewables for it to be useful from a GHG reduction perspective.

Another possibility of generating carbon free hydrogen is producing hydrogen from waste biomass (agro and forest waste) through gasification or stripping of hydrogen from methane producing hydrogen gas and solid carbon. Both are promising and is being researched actively.

Compressed hydrogen (at 700 bar pressure) has only 15% of the energy density of gasoline, so
storing the equivalent amount of energy at a vehicle refuelling station would require nearly
seven times the space. Also hydrogen is very light (and hence can escape more easily) and, to compound the problem, hydrogen is extremely explosive and its flame is almost colorless. So hydrigen transportation and storage infrastructure is a significant additional cost.

One option is the direct production and utilization of Ammonia (NH3) which can be easily liquified (like propane) and is much heavier and has lower flammability. It is much easier to transport. But it is toxic on inhalation, hence there are concerns about using it in cars. Another challenge is direct production of ammonia is difficult and the current conversion processes are not that cost effective or CO2 friendly. There is intense research going on in this sector and already start-ups are coming up that are producing direct green ammonia that can be used as a hydrogen carrier.
https://www.thyssenkrupp-industrial-solutions.com/power-to-x/en/green-ammonia

I am currently working on both generation of hydrogen from biomass sources and the utilization of ammonia as fuel in internal combustion engines. The projects are under research stage. Similar efforts by other researchers are going on around the world.

 

[sayak83]

There is also pressurised air, though that isn't tested enough, afaik. A depleted gas field near me was scheduled to be a test case but that got cancelled and the field is now used for gas storage. (We need that currently.)

Yes. There are working compressed air storage based energy systems. They work well with gas power plants. You need depleted gas fields, oil fields or salt caverns to get such things to work, so their potential growth is geographically limited.

 

[Guitar's Cry]

Quantitative predictions of extreme weather events is relatively new. So I could not yet find previous quantitative predictions that that match currently observed intensities. However, predictions of 1980-2000 climate models about future projected temperature rise has borne out very well with current observations. This can be seen here.

Study Confirms Climate Models are Getting Future Warming Projections Right – Climate Change: Vital Signs of the Planet

View attachment 68260

As we can see the observed post 2000 surface temperature closely track the ensemble mean of all pre-2000 climate models. This shows that the basic predictions even of very early models are robust.

Further recent studies have shown that, if we neglect climate change based forcing of the weather, we underpredict currently ongoing extreme weather events by about 50%. This roughly means that if climate change were not there, the number of extreme weather events (no. of heatwave days and no. of extreme rainfall days) would have been halved over the last decade.

Climate change means more extreme weather than predicted

Thanks for the information!

 

[sayak83]

People were able to walk the Bering "land
bridge" which was wider than the state of Alaska is now. Sea level has been rising for some time.

A more detailed reply

So there is something called the mid-Holocene maxima that lasted between 7000 years b.p. - 3000 years b.p. when temperatures where around 0.5 C above the 1750-1850 average values. This increase is the natural progression of the increasing warmth caused by increasing solar insolation (through the Milankovitch cycle) and the resultant shrinking of North Hemisphere ice sheets that decreased the earth's albedo and further warmed the globe. The estimated paleo temperature (with uncertainty range) is given (IPCC AR6 report)

Note however that such temperature changes occur over relatively long periods. So it takes a 1000 years for the mean temperature to rise or by 0.1 C up or down. The current growth rate of temperature increase of 1.1 C in a 120 year span is unseen in any past record. No geological, astronomical or ecological change can account for this. Only anthropogenic GHG emissions is the cause.

 

[sayak83]

Plus the existing CO2 will continue to warm us for quite some time. It is like going to bed and piling on a bunch of extra blankets because it is too cold. It takes a while to get to the new equilibrium temperature. And one may end up throwing off half of the blankets because they are too many. Sadly that is rather difficult to do with the atmosphere. It takes a long time to get excessive CO2 out.

And that leads me to my question for the OP:

If we became carbon neutral today what would be the "new normal" temperature? In other words, how much is the temperature going to go up due to what we have already added?

Since we are talking about "almost crossed the 1.5 C limit" I think that is the ceiling if we stopped now (or in 1-2 years) at least for the coming 100 years. We are at 1.1 C warming....so about 0.4 C more. This is the short term. In the long term (1000 year scales or more) we have shifted the climate from "Ice-House" state to "Cool-House" state already. What this means is at current CO2 levels, all Northern Hemisphere Ice Sheets cannot sustain themselves and will melt eventually.
The ice sheets will respond very slowly to the increased temperature and will continue to melt off for many centuries. That will also impact the albedo and cause further warming over century to millennial scales. With a stabilized CO2 conc. of 420-440 ppm we will be looking at a stabilized climate of mid-Pliocene (3 million years ago) when the earth was 2-2.5 C above preindustrial average. These correlates to what is called the warmhouse climate where there are no glaciers in the Northern Hemisphere (Ice free Greenland and North Pole) but glaciers remain the Antarctic. It may take a thousand years for this melting to happen, so if the climate stabilizes there, we will have enough time to move the 5-6 billion strong human population out of all our major coastal lands and countries and move them into continental interiors. This will be because sea levels will rise at least 30 m due to loss of Northern Hemosphere ice sheets. Of course, we may be able to prevent this too by technologies that absorb the CO2 back from the atmosphere in the 22nd or 23rd century.

Illustrative figure below of past climate and associate CO2 values and temperature. Note that current preindustrial average was 13.8 degrees and today we are around 14.9 degrees C. Our preindustrial CO2 was 280 ppm and now we are at 410 ppm. If we stabilized (optimistically) at below 440 ppm, even then we are looking at a Miocene climate when there was no ice sheet in the Northern Hemisphere.

 

[sayak83]

As the climate changes, what new kinds of storms might people come to expect?

Based on 1979-2017 dataset, tropical cyclones are increasing in intensity so that significant cyclones (category 3 or greater) are becoming more common.
https://doi.org/10.1073/pnas.1920849117
Models also predict that, along with increasing intensity, they are likely to cause increased rainfall (14% increase for a 2 C temperature rise) and stronger storm surge. They may travel slower and there may be (though this is less certain) fewer of them. So more of high intensity highly damaging cyclones but less number of total cyclones per year.
Tropical Cyclones and Climate Change Assessment: Part II: Projected Response to Anthropogenic Warming in: Bulletin of the American Meteorological Society Volume 101 Issue 3 (2020)

 

[zerogain]

So...
I teach three graduate level courses on Climate Change Physics, Sustainable Energy Technology and Combustion Science and Biofuels. Since there seems to be a lot of politically charged what-aboutery going on in these topics in the forum, I thought it would be a good idea to open a thread for anyone to ask me any question related to climate change science and Energy Technology Transitions going on in the world. Hopefully I can provide science based insightful answers...at least I will try.

So...shoot.

Good day to you sir , are you sure you want my questions ? What I mean by this is that my questions maybe beyond your level of expertise and I wouldn't want you to embarrass yourself by not knowing the answer .

I'll start with a simple question that involves fossil fuels !

I have 1kg mass of coal and I transform that into usable energy . The transformation of the coal converts the coal into gases and ash .

The total mass after the transformation remains 1kg .

Using the formula E=mc^2 , the total energy before transformation is equal to the total energy after transformation .

My question is , how can this fossil fuels transformation add energy to the Earths system when the math is equal before and after the transformation ?

 

[sayak83]

Good day to you sir , are you sure you want my questions ? What I mean by this is that my questions maybe beyond your level of expertise and I wouldn't want you to embarrass yourself by not knowing the answer .

I'll start with a simple question that involves fossil fuels !

I have 1kg mass of coal and I transform that into usable energy . The transformation of the coal converts the coal into gases and ash .

The total mass after the transformation remains 1kg .

Using the formula E=mc^2 , the total energy before transformation is equal to the total energy after transformation .

My question is , how can this fossil fuels transformation add energy to the Earths system when the math is equal before and after the transformation ?

It does not add energy to the Earth system. In fact after the burning of that 1kg of coal, earth will contain less energy than it had before as part of the thermal energy of the resultant fire escapes to outer space as energy containing electromagnetic waves. The thermal heat gained by air through the entry of the hot gases also will eventually radiate out to space and will be lost. So earth loses energy when any solid fuel (coal, oil, gas) is burnt.

 

[zerogain]

It does not add energy to the Earth system. In fact after the burning of that 1kg of coal, earth will contain less energy than it had before as part of the thermal energy of the resultant fire escapes to outer space as energy containing electromagnetic waves. The thermal heat gained by air through the entry of the hot gases also will eventually radiate out to space and will be lost. So earth loses energy when any solid fuel (coal, oil, gas) is burnt.

I agree , there is nothing gained by transforming the coal .

Why does the world think that fossil fuels are causing global warming ?

 

[sayak83]

I agree , there is nothing gained by transforming the coal .

Why does the world think that fossil fuels are causing global warming ?

Because they are, but the combustion process and its energy balance has nothing to do with it.
The problem is that fossil fuels, when they burn, emit carbon-di-oxide. Think of methane (which is present in natural gas). When it burns the reaction is
CH4 + 2O2 = CO2 + 2H2O.
So every molecule of methane, when it burns, generated one molecule of carbon dioxide that accumulates in the atmosphere.
Carbon dioxide is a molecule that is very effective in trapping heat radiation. Hence as CO2 increases in the atmosphere, the earth is less able to radiate and loose heat into space that it had been gaining by absorbing sunlight throughout the day. So as the daily heat gained by the earth from the sun exceeds the daily heat lost to space through radiation from earth, slowly the extra heat energy builds up in earth's ocean and the atmosphere and their temperature increases.

The same thing would have happened if you brough a trillion litre tank of CO2 from somewhere and released the gas into the atmosphere. Fossil fuel burning is currently the way CO2 is entering the atmosphere, and that is why it is problematic.

 

[zerogain]

Because they are, but the combustion process and its energy balance has nothing to do with it.
The problem is that fossil fuels, when they burn, emit carbon-di-oxide. Think of methane (which is present in natural gas). When it burns the reaction is
CH4 + 2O2 = CO2 + 2H2O.
So every molecule of methane, when it burns, generated one molecule of carbon dioxide that accumulates in the atmosphere.
Carbon dioxide is a molecule that is very effective in trapping heat radiation. Hence as CO2 increases in the atmosphere, the earth is less able to radiate and loose heat into space that it had been gaining by absorbing sunlight throughout the day. So as the daily heat gained by the earth from the sun exceeds the daily heat lost to space through radiation from earth, slowly the extra heat energy builds up in earth's ocean and the atmosphere and their temperature increases.

The same thing would have happened if you brough a trillion litre tank of CO2 from somewhere and released the gas into the atmosphere. Fossil fuel burning is currently the way CO2 is entering the atmosphere, and that is why it is problematic.

Ok , I see what they are saying but doesn't the C02 pre-exist within the mass before the transformation ?

Anology - I have a box of smarties and tip them on the floor , the red smarties and the blue smarties are now separated but the total number of smarties remains the same . I had red smarties and blue smarties in my box that could conserve heat , the total heat they can conserve within the box and out of the box doesn't change ?

 

[sayak83]

Ok , I see what they are saying but doesn't the C02 pre-exist within the mass before the transformation ?

Anology - I have a box of smarties and tip them on the floor , the red smarties and the blue smarties are now separated but the total number of smarties remains the same . I had red smarties and blue smarties in my box that could conserve heat , the total heat they can conserve within the box and out of the box doesn't change ?

Energy is conserved as well as the elements (C, H, O). But molecular identity is not conserved, nor the molecular properties. CO2 as a molecule is being created (with its unique properties) during the combustion process and the fuel molecule (carbon or methane as the case may be) is being destroyed during the combustion process. Its the properties that the chemical compound CO2 has, that coal or methane did not, which is causing the problem.

 

[zerogain]

Energy is conserved as well as the elements (C, H, O). But molecular identity is not conserved, nor the molecular properties. CO2 as a molecule is being created (with its unique properties) during the combustion process and the fuel molecule (carbon or methane as the case may be) is being destroyed during the combustion process. Its the properties that the chemical compound CO2 has, that coal or methane did not, which is causing the problem.

I disagree and my reason for this is that a piece of coal is much more dense than the transformed product . A piece of coals conservation of thermal energy is higher than the transformed product .
Thermal energy created from the transformation is always outward bound .

Anology - All heat goes to heaven , all electrical charge goes to hell !

Isn't my anology the cause of global warming ?

v(Q) = -ve where v is velocity , Q is electrical charge and -ve is a negative vector .

The Earth is full of conductive material and we know that electrical charge is attracted to conductive things !

(m1*Q^3)/t

You may not recognise this math but it reads true in regards to the physical process . Charge is conserved for a very long time compared to thermal energy .

 

[exchemist]

I disagree and my reason for this is that a piece of coal is much more dense than the transformed product . A piece of coals conservation of thermal energy is higher than the transformed product .
Thermal energy created from the transformation is always outward bound .

Anology - All heat goes to heaven , all electrical charge goes to hell !

Isn't my anology the cause of global warming ?

v(Q) = -ve where v is velocity , Q is electrical charge and -ve is a negative vector .

The Earth is full of conductive material and we know that electrical charge is attracted to conductive things !

(m1*Q^3)/t

You may not recognise this math but it reads true in regards to the physical process . Charge is conserved for a very long time compared to thermal energy .

So here we go again. I repeat below the text I have just posted on the other thread started today by @zerogain :

Aha, Theorist/Sustainer/James Blunt/ANEWDAWN/The Broken Soul etc., etc., back again, as yet another sockpuppet, with more nonsense.

It's been a while, but evidently too much to hope that he had gone away for good.

I wonder how his neurological reference frames are coming along, these days........

Just so readers are aware, the game is usually to start a discussion based on some semi-scientific nonsense and then to keep it going by means of replies with just enough science to keep people responding, but simultaneously adding a drip-feed of new nonsense, requiring further requests for correction, requests for clarification and so on. I suppose the idea is see how long he can make it last before people give up or, on science forms at least, he gets banned as a sock or for time-wasting. (Here on RF he adds a bit of religious-sounding mumbo jumbo, hence the equation with God in it.)

Readers looking at the series of posts on @sayak83 's excellent thread here will note the process I have described is being followed exactly. He's just arrived on the forum and immediately he's going to fill a good science thread with trash, if people keep responding to him.