Climate Change and Political inertness

Since the season of goodwill and general cheerfulness is approaching, it seems wrong to present even more bad news for this rather dismal year, yet we cannot hide from it, The problem was presented in Nature (  and relates to the Thwaites glacier. This glacier flows off the Antarctic continent into the Southern ocean. The glacier is 120 kilometers wide and about two thirds of this flows into the Southern Ocean, but one third runs into its eastern ice shelf. Here, the flow grinds to a halt because the ice out at sea hits an underwater mountain that is about 40 kilometres offshore. The Mountain is stopping the ice from flowing.

Unfortunately, thanks to the warmer water flowing underneath, that part of the glacier is becoming unstuck from the mountain, and this is causing cracking and fracturing across parts of the ice shelf. The fractures are propagating through the ice at several kilometres per year, and are heading towards thinner ice, which may lead to the whole lot shattering. To add to the problem there is tidal flexing as the glacier starts to separate from the rock and the “up and down” movement with the tides causes the glacier to flex further upstream, including where it is over land. Because of this flexing, warm water from the Southern Ocean could make its way beneath the glacier more easily.

Current estimates are that this mass of ice over the water could shatter within five years, which would release an huge mass of icebergs into the Southern Ocean, and the whole glacier could start flowing much faster into the sea. That means sea level rise. Currently the Thwaites already loses around fifty billion tonnes of ice each year and causes 4% of global sea level rise. If this eastern ice shelf collapses, ice would flow three times faster into the sea. If the glacier were to collapse completely sea levels would rise 65 centimetres. The glacier itself is moving towards the sea at about a mile each year. This is a fairly fast moving glacier.

So, what do we do about it. In this case it is probably impossible to do much. There is no way to stop a glacier moving. The only possible thing to do to stop the sea level rise would be to somehow engineer more snow to fall further inland to Antarctica. Fifty billion tonnes of snow each year would cancel out the sea level rise, but we all know that is not about to happen any time soon. But not to worry. Senator Manchin does not believe in climate change as a hazard, and he will torpedo President Biden’s efforts to get the US to do something. This Senator wants to burn more coal, and this one man will torpedo everyone else’s limited efforts. So is the Senator right? No. We might not be able to stop the Thwaites, but there are worse problems downstream we can still stop if we act before they become activated. Of course, he is not alone. Australia is selling more coal, China is building more coal-foired power stations, Germany has turned of nuclear to burn lignite. A cartoon in our paper had it: the Devil was reading about our activities and he said, “Aw, no fun. They’re not even pretending to try now.”

The nature of the problem is what we call hysteresis. If you have an equilibrium, such as when there is no change of temperature in an object over time, this arises because the heat loss equals the heat input. Now, suppose you increase the heat input a little. Now we are out of equilibrium, but since the heat loss depends on the temperature what you expect is the temperature will rise to reach the equilibrium position corresponding to where the heat loss now equals the heat input. Unfortunately, it doesn’t quite work like that. Suppose I have a lump of iron, and I increase the amount of heat going into it. The surface may well get warmer, but heat then starts flowing into the inside of the object. It takes time before the object reaches the new temperature. With something like ice, it is worse. The ice will warm, but once it gets to its melting point the increased heat flowing in starts to melt the ice. The ice stays at the same temperature. If we increase the heat flow inwards there is no change, other than the ice melts faster. Then, when it has all melted, suddenly the temperature starts to increase quickly.

To some extent, that is what has happened on our planet. Our greenhouse effect has been slowing the heat loss to space, and since the heat input remains the same, effectively the system is absorbing more heat. However, to start with all that happened was the surface of the oceans warmed up and some ice melted. So we ignored the problem because we observed no change in temperature, and poured more heat in. All that did was warm more water and melt more ice. The problem then is that we have now reached the point where the increase in heat that we are pouring into the Earth is starting to reach the point where the effects that absorbed heat without altering our temperature too much have now reached the end of their capacity. We are now going to make major changes to the planet, and we cannot stop them because the forces are already in place to generate far more heat.

Another characteristic of hysteresis is you cannot reverse what you have done simply by stopping increasing the heat input. Because the ice is melting because the water is above its freezing point, if we stopped adding heat now and stopped all greenhouse emissions, the oceans are still warm and the melting continues. However, there are thresholds. One calculation (Nature 585 (2020) p 538) indicated that for every degree of global temperature rise up to 2 degrees above pre-industrial levels will lead to 1.3 metres of sea-level rise. Between 2 – 6 degrees of warming it doubles to 2.4 metres per degree, and between 6 – 9 degrees, we get an extra 10 meters per degree. Further, the nature of hysteresis is that this is irreversible. If we want to turn it around we have to reduce global temperatures to one degree below what they were in 1850.

With that dismal thought, I wish you all a very Merry Christmas and all the best for 2022. This will be my last post for the year, and as usual I shall resume in mid-January. Finally, there are still my ebooks on the Smashwords sale.

Plastics and Rubbish

In the current “atmosphere” of climate change, politicians are taking more notice of the environment, to which as a sceptic I notice they are not prepared to do a lot about it. Part of the problem is following the “swing to the right” in the 1980s, politicians have taken notice of Reagan’s assertion that the government is the problem, so they have all settled down to not doing very much, and they have shown some skill at doing very little. “Leave it to the market” has a complication: the market is there to facilitate trade in which all the participants wish to offer something that customers want and they make a profit while doing it. The environment is not a customer in the usual sense and it does not pay, so “the market” has no direct interest in it.

There is no one answer to any of these problems. There is no silver bullet. What we have to do is chip away at these problems, and one that indicates the nature of the problem is plastics. In New Zealand the government has decided that plastic bags are bad for the environment, so the single use bags are no longer used in supermarkets. One can argue whether that is good for the environment, but it is clear that the wilful throwing away of plastics and their subsequent degradation is bad for it. And while the disposable bag has been banned here, rubbish still has a lot of plastics in it, and that will continue to degrade. If it were buried deep in some mine it probably would not matter, but it is not. So why don’t we recycle them?

Then first reason is there are so many variations of them and they do not dissolve in each other. You can emulsify a mix, but the material has poor strength because there is very little binding at the interface of the tiny droplets. That is because they have smooth surfaces, like the interface between oil and water. If the object is big enough this does not matter so much, thus you can make reasonable fence posts out of recycled plastics, but there really is a limit to the market for fence posts.

The reason they do not dissolve in each other comes from thermodynamics. For something to happen, such as polymer A dissolving in polymer B, the change (indicated by the symbol Δ) in what is called the free energy ΔG has to be negative. (The reason it is negative is convention; the reason it is called “free” has nothing to do with price – it is not free in that sense.) To account for the process, we use an equation

            ΔG = ΔH -T ΔS

ΔH reflects the change of energy between each molecule in its own material and in solution of the other material. As a general rule, molecules favour having their own kind nearby, especially if they are longer because the longer they are the interactions per atom are constant for other molecules of the same material, but other molecules do not pack as well. Thinking of oil and water, the big problem for solution is that water, the solvent, has hydrogen bonds that make water molecules stick together. The longer the polymer, per molecule that enhances the effect. Think of one polymer molecule has to dislodge a very large number of solvent molecules. ΔS is the entropy and it increases as the degree of randomness increases. Solution is more random per molecule, so whether something dissolves is a battle between whether the randomness per molecule can overcome the attractions between the same kind. The longer the polymer, the less randomness is introduced and the greater any difference in energy between same and dissolved. So the longer the polymers, the less likely they are to dissolve in each other which, as an aside, is why you get so much variety in minerals. Long chain silicates that can alter their associate ions like to phase separate.

So we cannot recycle, and they are useless? Well, no. At the very least we can use them for energy. My preference is to turn them, and all the organic material in municipal refuse, into hydrocarbons. During the 1970s oil crises the engineering was completed to build a demonstration plant for the city of Worcester in Massachusetts. It never went ahead because as the cartel broke ranks and oil prices dropped, converting wastes to hydrocarbon fuels made no economic sense. However, if we want to reduce the use of fossil fuels, it makes a lot of sense to the environment, IF we are prepared to pay the extra price. Every litre of fuel from waste we make is a litre of refined crude we do not have to use, and we will have to keep our vehicle fleet going for quite some time. The basic problem is we have to develop the technology because the engineering data for that previous attempt is presumably lost, and in any case, that was for a demonstration plant, which is always built on the basis that more engineering questions remain. As an aside, water at about 360 degrees Centigrade has lost its hydrogen bonding preference and the temperature increase means oil dissolves in water.

The alternative is to burn it and make electricity. I am less keen on this, even though we can purchase plants to do that right now. The reason is simple. The combustion will release more gases into the atmosphere. The CO2 is irrelevant as both do that, but the liquefaction approach sends nitrogen containing material out as water soluble material which could, if the liquids were treated appropriately, be used as a fertilizer, whereas in combustion they go out the chimney as nitric oxide or even worse, as cyanides. But it is still better to do something with it than simply fill up local valleys.

One final point. I saw an item where some environmentalist was condemning a UK thermal plant that used biomass arguing it put out MORE CO2 per MW of power than coal. That may be the case because you can make coal burn hotter and the second law of thermodynamics means you can extract more energy in the form of work. (Mind you, I have my doubts since the electricity is generated from steam.) However, the criticism shows the inability to understand calculus. What is important is not the emissions right now, but those integrated over time. The biomass got its carbon from the atmosphere say forty years ago, and if you wish to sustain this exercise you plant trees that recover that CO2 over the next forty years. Burn coal and you are burning carbon that has been locked away from the last few million years.

What to do about Climate Change

As noted in my previous post, the IPCC report on climate change is out. If you look at the technical report, it starts with pages of corrections. I would have thought that in these days the use of a word processor could permit the changes to be made immediately, but what do I know? Anyway, what are the conclusions? As far as I can make out, they have spent an enormous effort measuring greenhouse gas emissions and modelling, and have concluded that greenhouse gases are the cause of our problem and if we stopped emitting right now, totally, things would not get appreciably worse than they are now over the next century. As far as I can make out, that is it. They argue that CO2 emissions give a linear effect and for every trillion tonnes emitted, temperatures will rise by 0.45 Centigrade degrees, with a fairly high error margin. So we have to stop emitting.

The problem is, can we? In NZ we have a very high fraction of our electricity from renewable sources and we recently had a night of brown-outs in one region. It was the coldest night of the year, there was a storm over most of the country, but oddly enough there was hardly any wind at a wind farm. A large hydro station went out as well because the storm blew weeds into an intake and the station had to shut down and clean it out. The point is that when electricity generation is a commercial venture, it is not in the generating companies’ interests to have a whole lot of spare capacity and it make no sense to tear down what is working well and making money to spend a lot replacing it. So, the policy of using what we have means we are stuck where we are. China has announced, according to our news, that its coal-fired power stations will maximise and plateau their output of CO2 in about ten years. We have no chance of zero emissions in the foreseeable future. Politicians and environmentalists can dream on but there is too much inertia in an economy. Like a battleship steering straight for the wharf, the inevitable will happen.

Is there a solution? My opinion is, if you have to persist in reducing the heat being radiated to space, the best option is to stop letting so much energy from the sun into the system. The simplest experiment I can think of is to put huge amounts of finely dispersed white material, like the silica a volcano puts up, over the North Polar regions each summer to reflect sunlight back to space. If we can stop as much winter ice melting, we would be on the way to stop the potential overturn of the Gulf Stream and stop the Northern Siberian methane emissions. Just maybe this would also encourage more snow in the winter as the dust falls out.

Then obvious question is, how permanent would such a dispersion be? The short answer is, I don’t know, and it may be difficult to predict because of what is called the Arctic oscillation. When that is in a positive phase it appears that winds tend to circulate over the poles, so it may be possible to maintain dust over summer. It is less clear what happens in the negative phase. However, either way someone needs to calculate how much light has to be blocked to stop the Arctic (and Antarctic) warming. Maybe such a scheme would not be practical, but unless we at least make an effort to find out, we are in trouble.

This raises the question of who pays? In my opinion, every country with a port benefits if we can stop major sea level rising, so all should. Of course, we shall find that not all are cooperative. A further problem is that the outcome is somewhat unpredictable. The dust only has to last during the late spring and summer, because the objective is to reflect sunlight. For the period when the sun is absent it is irrelevant. We would also have to be sure the dust was not hazardous to health but we have lived through volcanic eruptions that have caused major lowering of the temperature world-wide so there will be suitable material.

There will always be some who lose on the deal. The suggestion of putting the dust over the Arctic would make the weather less pleasant in Murmansk, Fairbanks, Yukon, etc, but it would only return it to what it used to be. It is less clear what it would do elsewhere. If the arctic became colder, presumably there would be colder winter storms in more temperate regions. However, it might be better that we manage the climate than then planet does, thus if the Gulf Stream went, Europe would suffer both rising sea levels and temperatures and weather more like that of Kerguelen. In my opinion, it is worth trying.

But what is the betting any proposal for geoengineering has no show of getting off the ground? The politically correct want to solve the problem by everyone giving up something, they have not done the sums to estimate the consequences, and worse, some will give things up but enough won’t so that such sacrifices will be totally ineffective. We have the tragedy of the commons: if some are not going to cooperate and the scheme hence must fail, why should you even try? We need to find ways of reducing emissions other than by stopping an activity, as opposed to the emission.

Climate Change: Are We Baked?

The official position from the IPCC’s latest report is that the problem of climate change is getting worse. The fires and record high temperatures in Western United States and British Columbia, Greece and Turkey may be portents of what is coming. There have been terrible floods in Germany and New Zealand has had its bad time with floods as well. While Germany was getting flooded, the town of Westport was inundated, and the Buller river had flows about 30% higher than its previous record flood. There is the usual hand-wringing from politicians. Unfortunately, at least two serious threats that have been ignored.

The first is the release of additional methane. Methane is a greenhouse gas that is about 35 times more efficient at retaining heat than carbon dioxide. The reason is absorption of infrared depends on the change of dipole moment during absorption. CO2 is a linear molecule and has three vibrational modes. One involves the two oxygen atoms both moving the same way so there is no change of dipole moment, the two changes cancelling each other. Another is as if the oxygen atoms are stationary and the carbon atom wobbles between them. The two dipoles now do not cancel, so that absorbs, but the partial cancellation reduces the strength. The third involves molecular bending, but the very strong bond means the bend does not move that much, so again the absorption is weak. That is badly oversimplified, but I hope you get the picture.

Methane has four vibrations, and rather than describe them, try this link:

Worse, its vibrations are in regions totally different from carbon dioxide, which means it is different radiation that cannot escape directly to space.

This summer, average temperatures in parts of Siberia were 6 degrees Centigrade above the 1980 – 2000 average and methane is starting to be released from the permafrost. Methane forms a clathrate with ice, that is it rearranges the ice structure and inserts itself when under pressure, but the clathrate decomposes on warming to near the ice melting point. This methane has formed from the anaerobic digestion of plant material and been trapped by the cold, so if released we get delivered suddenly all methane that otherwise would have been released and destroyed over several million years. There are about eleven billion tonnes of methane estimated to be in clathrates that could be subject to decomposition, about the effect of over 35 years of all our carbon dioxide emissions, except that as I noted, this works in a totally fresh part of the spectrum. So methane is a problem; we all knew that.

What we did not know a new source has been identified as published in the Proceedings of the National Academy of Sciences recently. Apparently significantly increased methane concentrations were found in two areas of northern Siberia: the Tamyr fold belt and the rim of the Siberian Platform. These are limestone formations from the Paleozoic era. In both cases the methane increased significantly during heat waves. The soil there is very thin so there is very little vegetation to decay and it was claimed the methane was stored in and now emitted from fractures in the limestone.

The  second major problem concerns the Atlantic Meridional Overturning Circulation (AMOC), also known as the Atlantic conveyor. What it does is to take warm water that gets increasingly salty up the east Coast of the US, then switch to the Gulf Stream and warm Europe (and provide moisture for the floods). As it loses water it gets increasingly salty and with its increased density it dives to the Ocean floor and flows back towards the equator. Why this is a problem is that the melting Northern Polar and Greenland ice is providing a flood of fresh water that dilutes the salty water. When the density of the water is insufficient to cause it to sink this conveyer will simply stop. At that point the whole Atlantic circulation as it is now stops. Europe chills, but the ice continues to melt. Because this is a “stopped” circulation, it cannot be simply restarted because the ocean will go and do something else. So, what to do? The first thing is that simply stopping burning a little coal won’t be enough. If we stopped emitting CO2 now, the northern ice would keep melting at its current rate. All we would do is stop it melting faster.

Venus with a Watery Past?

In a recent edition of Science magazine (372, p1136-7) there is an outline of two NASA probes to determine whether Venus had water. One argument is that Venus and Earth formed from the same material, so they should have started off very much the same, in which case Venus should have had about the same amount of water as Earth. That logic is false because it omits the issue of how planets get water. However, it argued that Venus would have had a serious climatic difference. A computer model showed that when planets rotate very slowly the near absence of a Coriolis force would mean that winds would flow uniformly from equator to pole. On Earth, the Coriolis effect leads to the lower atmosphere air splitting into three  cells on each side of the equator: tropical, subtropical and polar circulations. Venus would have had a more uniform wind pattern.

A further model then argued that massive water clouds would form, blocking half the sunlight, then “in the perpetual twilight, liquid water could have survived for billions of years.”  Since Venus gets about twice the light intensity as Earth does, Venusian “perpetual twilight” would be a good sunny day here. The next part of the argument was that since water is considered to lubricate plates, the then Venus could have had plate tectonics. Thus NASA has a mission to map the surface in much greater detail. That, of course, is a legitimate mission irrespective of the issue of water.

A second aim of these missions is to search for reflectance spectra consistent with granite. Granite is thought to be accompanied by water, although that correlation could be suspect because it is based on Earth, the only planet where granite is known.

So what happened to the “vast oceans”? Their argument is that massive volcanism liberate huge amounts of CO2 into the atmosphere “causing a runaway greenhouse effect that boiled the planet dry.” Ultraviolet light now broke down the water, which would lead to the production of hydrogen, which gets lost to space. This is the conventional explanation for the very high ratio of deuterium to hydrogen in the atmosphere. The concept is the water with deuterium is heavier, and has a slightly higher boiling point, so it would be the least “boiled off”. The effect is real but it is a very small one, which is why a lot of water has to be postulated. The problem with this explanation is that while hydrogen easily gets lost to space there should be massive amounts of oxygen retained. Where is it? Their answer: the oxygen would be “purged” by more ash. No mention of how.

In my ebook “Planetary Formation and Biogenesis” I proposed that Venus probably never had any liquid water on its surface. The rocky planets accreted their water by binding to silicates, and in doing so helped cement aggregate together and get the planet growing. Earth accreted at a place that was hot enough during stellar accretion to form calcium aluminosilicates that make very good cements and would have absorbed their water from the gas disk. Mars got less water because the material that formed Mars had been too cool to separate out aluminosilicates so it had to settle for simple calcium silicate, which does not bind anywhere near as much water. Venus probably had the same aluminosilicates as Earth, but being closer to the star meant it was hotter and less water bonded, and consequently less aluminosilicates.

What about the deuterium enhancement? Surely that is evidence of a lot of water? Not necessarily. How did the gases accrete? My argument is they would accrete as solids such as carbides, nitrides, etc. and the gases would be liberated by reaction with water. Thus on the road to making ammonia from a metal nitride

M – N  + H2O   →  M – OH  +  N-H  ; then  M(OH)2    →  MO + H2O and this is repeated until ammonia is made. An important point is one hydrogen atom is transferred from each molecule of water while one is retained by the oxygen attached to the metal. Now the bond between deuterium and oxygen is stronger than that from hydrogen, the reason being that the hydrogen atom, being lighter, has its bond vibrate more strongly. Therefore the deuterium is more likely to remain on the oxygen atom and end up in further water. This is known as the chemical isotope effect, and it is much more effective at concentrating deuterium. Thus as I see it, too much of the water was used up making gas, and eventually also making carbon dioxide. Venus may never have had much surface water.

Geoengineering – to do or not to do?

Climate change remains an uncomfortable topic. Politicians continue to state it is such an important problem, and then fail to do anything sufficient to solve it. There seems to be an idea amongst politicians that if everyone drove electric vehicles, all would be well. Leaving aside the question as to whether over the life of a vehicle the electric vehicle actually emits less greenhouse gas (and at best, that is such a close call it is unlikely to have any hope of addressing the problem) as noted in my post

the world cannot sustain then necessary extractions to make it even vaguely possible. If that is the solution, why waste the effort – we are doomed.

As an article in Nature (vol 593, p 167, 2021) noted, we need to evaluate all possible options. As I have remarked in previous posts, it is extremely unlikely there is a silver bullet. Fusion power would come rather close, but we still have to do a number of other things, such as to enable transport, and as yet we do not have fusion power. So what the Nature article said is we should at least consider and analyse properly the consequences of geoengineering. The usual answer here is, horrors, we can’t go around altering the planet’s climate, but the fact is we have already. What do you think those greenhouse gases are doing?

The problem is that while the world has pledged to reduce emissions by 3 billion t of CO2 per year, even if this is achieved, and that is a big if, it remains far too little. Carbon capture will theoretically solve some of the problems, but it costs so much money for no benefit to the saver that you should not bet the house on that one. The alternative, as the Nature article suggests, is geoengineering. The concept is to raise the albedo of the planet, which reflects light back to space. The cooling effect is known: it happens after severe volcanic eruptions.

The basic concept of sending reflective stuff into the upper atmosphere is that it is short-term in nature, so if you get it wrong and there is an effect you don’t like, it does not last all that long. On the other hand, it is also a rapid fix and you get relatively quick results. That means provided you do things with some degree of care you can generate a short-term effect that is mild enough to see what happens, and if it works, you can later amplify it.

The biggest problem is the so-called ethical one: who decides how much cooling, and where do you cool? The article notes that some are vociferously opposed to it as “it could go awry in unpredictable ways”. It could be unpredictable, but the biggest problem would be that the unpredictability would be too small. Another listed reason to oppose it was it would detract from efforts to reduce greenhouse emissions. The problem here is that China and many other places are busy building new coal-fired electricity generation. Exactly how do you reduce emissions when so many places are busy increasing emissions? Then there is the question, how do you know what the effects will be? The answer to that is you carry out short-term mild experiments so you can find out without any serious damage.

The other side of the coin is, if we even stopped emissions right now, the existing levels will continue to heat the planet and nobody knows by how much. The models are simply insufficiently definitive. All we know is that the ice sheets are melting, and when they go, much of our prime agricultural land goes with it. Then there is the question of governance. One proposal to run small tests in Scandinavia ran into opposition from a community that protested that the experiments would offer a distraction from other reduction efforts. It appears that some people seem to think that with just a little effort this problem will go away. It won’t. One of the reasons for obstructing research is that the project will affect the whole planet. Yes, well so does burning coal in thermal generators, but I have never heard of the rest of the planet being consulted on that.

Is it a solution? I don’t know. It most definitely is not THE solution but it may be the only solution that acts quickly enough to compensate for a general inability to get moving, and in my opinion we badly need experiments to show what can be achieved. I understand there was once one such experiment, although not an intentional one. Following the grounding of aircraft over the US due to the Twin Tower incident, I gather the temperatures the following two days went up by over a degree. That was because the ice particles due to jet exhausts were no longer being generated. The advantages of an experiment using ice particles in the upper atmosphere is you can measure what happens quickly, but it quickly goes away so there will be no long term damage. So, is it possible? My guess is that technically it can be managed, but the practical issues of getting general consent to implement it will take so long it becomes more or less irrelevant. You can always find someone who opposes anything.

Fighting Global Warming Naturally?

In a recent edition of Nature (593, pp191-4) it was argued that to combat global warming, removing carbon from the atmosphere, which is often the main focus, should instead be reviewed in light of how to lower global temperatures. They note that the goal of reducing warming from pre-industrial times to two Centigrade degrees cannot be met solely through cuts to emissions so carbon dioxide needs to be removed from the atmosphere. The rest of the article more or less focused on how nature could contribute to that, which was a little disappointing bearing in mind they had made the point that this was not the main objective. Anyway, they went on to claim nature-based solutions could lower the temperature by a total of 0.4 degrees by 2100. Then came the caveats. If plants are to absorb carbon dioxide, they become less effective if the temperatures rise too high for them.  

Some statistics: 70% of Earth’s land surface has been modified by humanity; since 1960 we have modified 20% of it. Since 1960 changes include (in million square kilometers): urban area  +0.26; cropland +1.0; pasture +0.9; forestry -0.8.

The proposal involves three routes. The first is to protect current ecosystems, which includes stopping deforestation. This is obvious, but the current politicians, such as in Brazil, suggest this receives the comment, “Good luck with that one.” This might be achieved in some Western countries, but then again they have largely cut their forests down already. If we are going to rely on this we have a problem.

The second is to restore ecosystems so they can absorb more carbon. Restoration of forest cover is an obvious place to start. However, they claim plantation forests do not usually give the same benefits as natural forest. The natural forest has very dense undergrowth. Unless there are animals to eat that you may end up generating fuel to start forest fires, which wipe out all progress. Wetlands are particularly desirable because they are great at storing carbon, and once underway, they act rather quickly. However, again this is a problem. Wetlands, once cleared and drained are somewhat difficult to restore because the land tends to have been altered in ways to avoid the land reverting, so besides stopping current use, the alterations have to be removed. 

Notwithstanding the difficulties, there is also a strong reason to create reed beds that also grow algae. The reason is they also take up nitrogen and phosphate in water. Taking up ammoniacal wastes is very important because if part of the nitrogen waste is oxidized, or nitrates have been used as fertilizer, ammonium nitrate will decompose to form nitrous oxide, which is a further greenhouse gas that is particularly difficult because it absorbs in quite a different part of the infrared spectrum, and it has no simple decay route or anything that will absorb it. Consequently, what we put in the air could be there for some time. 

 The third is to improve land management, for timber, crops and grazing, Thus growing a forest on the borders of a stream should add carbon storage, but also reduce flooding and enhance fish life. An important point is that slowing runoff also helps prevent soil loss. All of this is obvious, except, it seems, to officials. In Chile, the government apparently gave out subsidies for pine and eucalyptus planting that led to 1.3 million hectares being planted. What actually happened was that the land so planted had previously been occupied with original forest and it is estimated that the overall effect was to emit 0.05 million t of stored carbon rather than sequester the 5.6 million t claimed. A particular piece of “politically correct” stupidity occurred here. The Department of Conservation, being green inclined, sent an electric car for its people to drive around Stewart Island, the small southern island of New Zealand. It has too small a population to warrant an electric cable to connect it to the national grid, so all the electricity there is generated by burning diesel!

The paper claims it is possible to remove 10 billion tonne of CO2 fairly quickly, and 20 billion tonne by 2055. However, my feeling is that is a little like dreaming because I assume it requires stopping the Amazon and similar burnoffs. On the other hand, even if it does not work out exactly right, it still has benefits. Stopping flooding and erosion while having a more pleasant environment and better farming practices might not save the planet, but it might make your local bit of planet better to live in.

The Non-Green Internet

Did you know that by reading this you are contributing to climate change. Oops! Seriously, it is claimed that by 2025 the internet will use a fifth of the world’s electricity, assuming no massive increase in the use of electric transport. And before you decide to stop reading this to save the climate, apart from the use of your computer, you make no difference whether you read it or not. On the other hand, apparently Bitcoin mining consumes the total electricity consumption of Switzerland, so steady on there. The infrastructure for the internet is always on, and the messages you send make no difference. Sorry but you cannot save the world by not sending that email, and of course had you posted a physical letter, there would have been significant greenhouse gas emissions from getting the letter from your desk to wherever.

People that store their work in the cloud do contribute. A major data centre consumes about 30 GWh per year, and the UK has about 450 data centres. After all, all this rubbish we write and record has to be stored somewhere. That raises the question, how many data centres will have to be built? These centres are where the “cloud” resides, and if everyone is busy filling them up, what happens when it is no longer so easy to build more? How long can we continue recording everything?

How much has to be recorded for posterity? All those pointless Facebook posts that make pointless comments (rude or otherwise) or show a few emoticons. If they were deleted after a few weeks, would anyone notice? The problem then, of course, is, who decides? Notice the recent fuss about Trump not being allowed to tweet. In my opinion, if they had done that to him when he became President he would have been more effective but that is another matter. The problem is, when you appoint a “Great Deleter” you open up so many cans of worms it is not funny. Some of what we store will be of interest historically, perhaps especially Trump’s tweets. Right now photos recovered from long ago fascinate many of us. I know that I recently downloaded a whole lot of photos of the area where my mother grew up, and where, still a long time ago, I drove her back to have a look around. So for me, it was of interest to hear her say what was there, where, and now be able to see it. Quite simply, in two lifetimes everything has changed remarkably, and what was there is no longer, other than in memories, and memories die. Also, storing photos in data centres takes up much less space than storing hard copies. Of the hard copies left, many have been lost, but how much of what is stored digitally will be available in a hundred years?

Much of what is stored digitally may become unreadable. In the scientific community, for example, the Royal Society for Chemistry has noted that computations carried out in the last century often use code that nobody now understands. Some of us have computer files written many years ago, but unless they were updated and converted into new formats they are unreadable other than on an ancient computer. Back to electricity, either we can go into our shell and try to live like the Amish, do something about electricity generation, or be like politicians and make encouraging speeches and hope all gets well. Apparently, Facebook, Apple, Google and others have committed to using 100% renewable electricity (although when is another question) and Microsoft claims that by 2050 it will have removed all the carbon emissions it has ever produced. These are noble aspirations, but so far, according to Greenpeace, only about 20% of the electricity used by the world’s data centres is renewable. Further, the data centres run uniform power consumption over the entire time. Solar is of little use during the night, and wind power fails when the wind is not blowing. If we rely heavily on such renewables, what happens when there are blackouts? And, of course, there is the question of the non-renewable resources used to build the computers in the cloud. So no, I do not think anyone will be reading my blogs in a hundred years. However, we should make more effort to generate electricity more sustainably. Unless we solve the fusion problem, I favour the liquid salt thorium-type reactor.

What are We Doing about Melting Ice? Nothing!

Over my more active years I often returned home from the UK with a flight to Los Angeles, and the flight inevitably flew over Greenland. For somewhat selfish reasons I tried to time my work visits in the northern summer, thus getting out of my winter, and the return flight left Heathrow in the middle of the day so with any luck there was good sunshine over Greenland. My navigation was such that I always managed to be at a window somewhere at the critical time, and I was convinced that by my last flight, Greenland was both dirtier and the ice was retreating. Dirt was from dust, not naughty Greenlanders, and it was turning the ice slightly browner, which made the ice less reflective, and thus would encourage melting. I was convinced I was seeing global warming in action during my last flight, which was about 2003.

As reported in “The Economist”, according to an analysis of 40 years of satellite data at Ohio State University, I was probably right. In the 1980s and 1990s, during Greenland summers it lost approximately 400 billion tonnes of ice each summer, by ice melting and by large glaciers shedding lumps of ice as icebergs into the sea. This was not critical at the time because it was more or less replenished by winter snowfalls, but by 2000 the ice was no longer being replenished and each year there was a loss approaching 100 billion t/a. By now the accumulated net ice loss is so great it has caused a noticeable change in the gravitational field over the island. Further, it is claimed that Greenland has hit the point of no return. Even if we stopped emitting all greenhouse gases now, it was claimed, more ice would be progressively lost than could be replaced.

So far the ice loss is raising the oceans by about a millimetre a year so, you may say, who cares? The problem is the end position is the sea will rise 7 metres. Oops. There is worse. Apparently greenhouse gases cause more effects at high latitudes, and there is a lot more ice on land at the Antarctic. If Antarctica went, Beijing would be under water. If only Greenland goes, most of New York would be under water, and just about all port cities would be in trouble. We lose cities, but more importantly we lose prime agricultural land at a time our population is expanding

So, what can be done? The obvious answer is, be prepared to move where we live. That would involve making huge amounts of concrete and steel, which would make huge amounts of carbon dioxide, which would make the overall problem worse. We could compensate for the loss of agricultural land, which is the most productive we have, by going to aquaculture but while some marine algae are the fastest growing plants on Earth, our bodies are not designed to digest them. We could farm animal life such as prawns and certain fish, and these would help, but whether productivity would be sufficient is another matter.

The next option is geoengineering, but we don’t know how to do it, and what the effects will be, and we are seemingly not trying to find out. We could slow the rate of ice melting, but how? If you answer, with some form of space shade, the problem is that orbital mechanics do not work in your favour. You could shade it some of the time, but so what? Slightly more promising might be to generate clouds in the summer, which would reflect more sunlight.

The next obvious answer (OK, obvious may not be the best word) is to cause more snow to fall in winter. Again, the question is, how? Generating clouds and seeding them in the winter might work, but again, how, and at what cost? The end result of all this is that we really don’t have many options. All the efforts at limiting emissions simply won’t work now, if the scientists at Ohio State are correct. Everyone has heard of tipping points. According to them, we passed one and did not notice until too late. Would anything work? Maybe, maybe not, but we won’t know unless we try, and wringing our hands and making trivial cuts to emissions is not the answer.

The Hangenberg Extinction

One problem of applying the scientific method to past events is there is seldom enough information to reach a proper conclusion. An obvious example is the mass extinction that we know occurred at the end of the Devonian period, and in particular, something called the Hangenberg event, which is linked to the extrinction of 44% of high-level vertebrate clades and 97% of vertebrate species. Only smaller species survived, namely sharks smaller than a meter in length and general fish less than ten centimeters in length. This is the time when most ammonites and trilobites, which had been successful for such a long time, failed to survive. One family of trilobites survived, only to be extinguished in the Permian extinction, another  of those that wiped out 90% of all species. 

So why did this happen? First, it is most likely the ecosystems had been stressed. The Hangenberg event occurred about 358 My ago, but before that, at about 382 My BP most jawless fish disappeared, while from 372 – 359 My BP there were a series of extinctions or climate changes known as the Kellwasser event (although it was almost certainly a number of events.) So for about 30 million years leading up to the Hangenberg event, there had been severe difficulties for life. At this stage, leaving aside insects and plants that had left the oceans, most life were in marine or freshwater environments and it was this life that appears to have suffered the most. That conclusion, however, may more reflect a relative paucity of land-based fossils. Climate change was almost certainly involved because over this period there was a series of sea level rises while the water became more anoxic. The causes of this are less than clear and there have been a numper of suggestions.

One possibility is an asteroid collision, and while impact craters can be found they cannot be dated sufficiently closely to be associated with any specific event. A more likely effect questions why anoxic? The climate  should have no direct effect on this, although the reverse is possible. The question is really was it the seas only that became anoxic? One possibility is that on land the late Devonian saw a dramatic change in plant life. In the early Devonian, plants had made it to land, but they were small leafy plants like liverworts and mosses. In the late Devonian they developed stems that could move water and nutrients, and suddenly huge plants emerged. One argument is that this caused a flood of nutrients through the weathering of rocks caused by the extensive root systems to flow down into the sea, which caused algal blooms, which led to anoxic conditions. Meanwhile, the huge forests of the Devonian may have reduced carbon dioxide levels, which would lead to glaciation, and the sea level fall in the very late Devonian. However, it does not explain sea level rise earlier. That may have arisen from extensive volcanism that occurred around 372 My ago, which would enhance greehouse warming. You can take your pick from these explanations because even the experts in the field are unsure.

Accordingly, a new theory has just emerged, namely Earth was bombarded by cosmic rays from a nearby supernova (Fields, et al., arXiv:2007.01887v1, 3rd July, 2020). This has the advantage that we can see why it is global. The specific event would be a core-collapse supernova. If this occurred within 33 light years from Earth, it would probably extinguish all life on Earth, but one about twice as far away, 66 light years, would exterminate much life, but not all. The mechanism is in part ozone depletion, but there is the possibility of enhanced nitrogen fixation in the atmosphere, which might lead to algal blooms. One of the good things about such a proposition is it is testable. Such an event would bombard Earth with isotopes that would otherwise be difficult to obtain, and one would be plutonium 244. There is no naturally occurring plutonium on Earth, so if some atoms were found in the fossils or in accompanying rock, that would support the supernova event.

So, is that what happened? My personal view is that is unlikely, and the reason I say that is that most of the damage would be done to life on land, and as I gather, the insects expanded into the Carboniferous period. The seas would be relatively protected because the incoming flux would be protected by the water. The nitrate fixation might cause an algal bloom and while a lot of energy would be required to saturate the world’s oceans, maybe there was sufficient. The finding of plutonium in the associated deposits would be definitive, however. The typical deposits were black shales overlaid by sandstone, and are easy to locate, so if there is plutonium in them, there is the answer. If there is not, does that mean the proposition is wrong? That is more difficult to answer, but the more samples that are examined from widespread sources, the more trouble for the proposition.

My preferred explanation is the ecological one, namely the development of tree ferns, etc. The Devonian extinction was slow, taking 24 million years, and while most marine extinctions occurred during what is called the Hangenberg event, the word event may be misleading. That specific period took 100,000 – 300,000 years, which is plenty of time for an ecological disaster to kill off that which cannot adapt. To put it into perspective, Homo Sapiens has been around for only 30,000 years, and effective for only about 10,000 years. Look at the ecological change. Now, think what will happen if we let climate change get out of control. We are already causing serious extinction of many species, but the loss of habitat if the seas rise will dwarf what we have done so far because our booming population has to eat. We should learn from the late Devonian.