Science and Climate Change

In the previous post, I questioned whether science is being carried out properly. You may well wonder, then, when this week the Intergovernmental Panel on Climate Change issued a rather depressing report, and a rather awkward challenge: according to their report, the world needed to limit the temperature rise to 1.5 degrees C between now and 2050, and to do that, it needed to cut carbon emissions by 45% by 2030, and net zero by 2050. Even then significant amounts of carbon have to be removed from the atmosphere. The first question is, then, is this real, and if so, why has the IPCC suddenly reduced the tolerable emissions? If their scientists previously predicted seriously lower requirements, why should these be considered better? There are two simple answers. The first is the lesser requirements were based on the assumption that nations would promptly reduce emissions. Most actually increased them. The second is more complicated.

The physics have been verified many times. However, predicting the effects is another matter. The qualitative effects are easily predicted, but to put numbers on them requires very complicated modelling. The planet is not an ideal object, and the calculation is best thought of as an estimate. What has probably happened is their modelling made a projection of what would happen, and they did this long enough ago that now that they can compare prediction with where we are now. That tells them how good the various constants they put into the model were. Such a comparison is somewhat difficult, but there are clear signs in our observations, and things are worse than we might hope for.

So, what are we going to do? Nothing dramatic is going to happen on 2040, or 2050. Change will be gradual, but its progress will be unstoppable unless very dramatic changes in our behaviour are made. The technical challenges here are immense. However, there are a number of important decisions to be taken because we are running short of time due to previous inaction. Do we want to defend what we have? Do we want to attempt to do it through sacrificing our life style, or do we want to attempt a more aggressive approach? Can we get sufficient agreement that anything we try will be properly implemented? Worst of all, do we know what our options are? Of these questions, I am convinced that through inaction, and in part the structural defects of academic science, the answer to the last question is no.

The original factor of required emissions reduction was set at 1990 as a reference point. What eventuated was that very few countries actually reduced any emissions, and most increased them. The few that did reduce them did that by closing coal-fired electricity generation and opted for burning natural gas. This really achieves little, and would have happened anyway. Europe did that, although France is a notable exception to this in that it has had significant nuclear power for a long time. Nuclear power has its problems, but carbon emissions are not one of them. The countries of the Soviet Union have also actually had emission reductions, although this is as much as anything due to the collapse of their economies as they made the rather stupid attempt to convert to “free market economics” which permitted a small number of oligarchs to cream the economy, sell off what they could, use what was usable, pay negligible wages and export their profits so they could purchase foreign football clubs. That reduced carbon emissions, but it is hardly a model to follow.

There is worse news. Most people by now have recognized that Donald Trump and the Republican party do not believe in global warming, while a number of other countries that are only beginning to industrialize want the right to emit their share of CO2 and are on a path to burn coal. Some equatorial countries are hell-bent on tearing down their rain forest, while warming in Siberia will release huge amounts of methane, which is about thirty times more potent than CO2. Further, if we are to totally change our way of life, we shall have to dismantle the energy-related infrastructure from the last fifty years or so (earlier material has probably already been retired) and replace it, which, at the very least will require billions of tonnes of carbon to make the required metals.

There will be some fairly predictable cries. Vegetarians will tell everyone to give up meat. Cyclists will tell everyone they should stop driving cars. In short, everyone will have ideas where someone else gives up whatever. One problem is that people tend to want to go for “the magic bullet”, the one fix to fix them all. Thus everyone should switch to driving electric vehicles. In the long term, yes, but you cannot take all those current vehicles off the road, and despite what some say, heavy trucks, major farm and construction equipment, and aircraft are going to run on hydrocarbons for the foreseeable future. People talk about hydrogen, but hydrogen currently requires massive steel bottles (unless you are NASA, or unless you can get hydrides to act reversibly). And, of course, there is a shortage of material to make enough batteries. Yes, electric vehicles, cycling, public transport and being a vegetarian are all noble contributions, but they are just that. Wind and solar power, together with some other sources, are highly desirable, but I suspect that something else, such as nuclear power must be adopted more aggressively. In this context, Germany closing down such reactors is not helpful either.

Removing CO2 from the atmosphere is not that easy either. There have been proposals to absorb it from the effluent gases of coal-fired power stations. Such scrubbing is not 100% efficient, but even if it were, it is not dealing with what is already there. My guess is, that can only be managed by plants in sufficient scale. While not extremely efficient, once going they look after themselves. Eventually you have to do something with the biomass, but restoring all the tropical rain forests would achieve something in the short term. My personal view is the best chances are to grow algae. The sea has a huge area and while we still have to learn how to do it, it is plausible, and the resultant biomass could be used to make biofuel.

No, it is not going to be easy. The real question is, can we be bothered trying to save what we have?

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Colonizing Mars

Recently, Elon Musk threw a Tesla car at Mars and somewhat carelessly, missed. How can you miss a planet? The answer is, not unsurprisingly, quite easily. Mars might be a planet, and planets might seem large, but they are staggeringly small compared with the solar system. But whatever else this achieved, it did draw attention back to thoughts of humans on Mars, and as an exercise, it is not simple to bring the two together. Stephen Hawking was keen on establishing a colony there, mainly as some sort of reserve for humanity in case we did something stupid with out own planet. Would we do that? Unfortunately, the answer is depressingly quite possibly.

So what is required to get to Mars? First, not missing. NASA has shown that it can do this, so in principle this problem is solved. The second requirement is to arrive at the surface at essentially zero vertical velocity, and NASA has not been quite so successful at that, nevertheless, we can assume that landing will be with a piloted shuttle, so this should be able to be done. So far, so good? Well, not quite, because when you get there you have to have enough “stuff” to ensure you can survive. If it is a scientific exploration, the people will be away for over two years, so at a minimum, they will need groceries for two years, unless they grow their own food. They will need their own oxygen and water unless they can recycle it. They will need some means of getting around or there is no point in going, and they will need some sort of habitat. If they are settlers they will need a lot more because they are not coming back.

The obvious first thing to for settlers to do is to have somewhere to live. We can assume that the ship that brought them will provide a temporary place, although if the ship is to be recycled back to earth and they came down in a shuttle, this is a priority. At the same time they must build facilities to grow their own food and make oxygen. This raises the question, how many people could actually grow food and guarantee to do it well enough not to starve in a totally different environment to here? I am not sure you can train for that, but even if you can, there will still need to be a lot of food taken as well as oxygen. However, let’s assume these settlers are really competent and they are raring to get on with it.

The first requirement would be enough area to do it, so they would need a giant glass house (or houses). That means glass, and metal to hold it, but there is worse. You have to pressurize it, because the Martian atmospheric pressure on average is only about ½% of Earth’s. That means you need a strong pump, but because of the aggressive nature of dust in the atmosphere much of the time, you need some form of filter. The air is about 95.3% carbon dioxide, about 2.7% nitrogen and 1.6% argon. If you want to recover the oxygen to breathe, you want to boost the nitrogen so that what is produced is breathable as air, and that requires a major gas separator. The best way is probably to seriously overpressurise it, so the carbon dioxide comes out as a liquid, and keep the rest. However, there is another problem: you need water, so that equipment will probably have to be made even more complicated so the water in the atmosphere can be recovered. The next problem is that if the glasshouse is to be pressurized, it has to be leak-proof. All the joints have to be sealed with something that will not decay under UV radiation, and worse than that, a deep footer is needed around the glasshouse. That means digging a deep trench, pouring concrete, and sealing the walls. Finally, the whole regolith inside the glasshouse has to be treated to decompose its strong oxidizing nature (but this does produce a small amount of oxygen) otherwise the soil will sterilize anything you plant, then you have to add some actual soil. Many of these operations would be best done mechanically, but they each need their own machine.

You may notice that all of these things costs weight, and that is not what is wanted on a space ship. So the question is, how much can be brought there? There is a second requirement. Every time you use a machine, you need fuel. That has to be electric, which means either batteries, which so far would require huge numbers to keep going all day, or fuel cells, but if fuel cells are selected, what will be the fuel? Note that two fuels are required; one to “burn” and the other to burn it in, as there is no oxygen in the atmosphere worth having. Either way, a serious energy producer is required because not only do you have to power things, but you have to keep your glasshouse warm. The night-time temperatures can drop below minus 100 degrees Centigrade. The most obvious source is nuclear, either fission or fusion, but that requires shielding and even more weight.

The above is just some of the issues. I wrote a novel (Red Gold) that involved Martian settlement. The weight of the two ships was twenty million tonne each, and each had a thermonuclear propulsion system that detached and could be used as power plants and mineral separation units later. The idea was that construction materials would be made there, but even if that is done, a huge amount of stuff has to be taken. Think of the cost of lifting forty million tonne of stuff from Earth into orbit alone. Why two ships? Because everything should be done in duplicate, in case something goes wrong. Why that much stuff? Because you want this not to be some horrible exercise in survival.

At this stage I shall insert a small commercial. Red Gold is a story of such colonization, and of fraud, and it includes a lot more about what it might take to colonize Mars. It is available on Kindle Countdown discounts from 13 – 19 April. (http://www.amazon.com/dp/B009U0458Y)