Global Warming and SF

Global Warming and SF

Global warming is an issue which is not going to go away, and that has implications for anyone writing fiction set in the foreseeable future. Any SF novel set within the next century or few which ignores this issue and its probable consequences will be likely to have a very short shelf-life before being seen as increasingly irrelevant. That doesn't mean that every such story should be about global warming, but that it should be set against a background which includes it – or the measures which were used to overcome it.

I don't, in this brief blog, want to rehearse the well-known basic arguments around global warming. Anyone who isn't yet convinced that this is happening as a result of human activities can read a wide variety of authoritative material on the web, such as the report of the US National Academies: Understanding and Responding to Climate Change; the Royal Society's Facts & Fictions about Climate Change; or, if you want the official 2007 report of the International Panel on Climate Change (the largest and most authoritative body studying this subject) go to the IPCC website. A more user-friendly summary can be found on Wikipedia, while I particularly recommend the New Scientist magazine's Climate Change: a guide for the Perplexed, since that also discusses the usual objections raised.

Instead, I want to focus on what might happen, and (in a later post) what might be done about it – subjects which provide very wide scope for science-fictional speculation. A recent conference of climate scientists in Copenhagen attracted some 2,500 delegates and heard 600 presentations over the three days. In the words of the New Scientist, "the majority [of these] showed the impacts of climate change would happen faster and be worse than previously thought". In other words, the predictions of the 2007 IPCC report are already being overtaken by events. This has been dramatically illustrated by the rapid shrinkage in summer Arctic ice cover.

This should be no great surprise. The rapid industrialisation of China (with a new coal-fired power station reportedly being built every week over the past few years) combined with the fact that very few countries have slowed down the increase in their CO2 output, was until recently boosting the rate of increase in atmospheric CO2 levels over that predicted by the IPCC. For all of its other unhappy consequences, the current economic recession should at least slow down the rate of change and provide a bit of a breathing space to get our environmental act together.

Despite this general view that conditions are changing quickly and that this will result in serious consequences for the global environment and for humanity, there is still much uncertainty over what precisely is going to happen. This is partly because no-one is certain of the exact link between the rate of increase in CO2 production and the rate and ultimate level of the global temperature increase; and similarly no-one knows the exact implications, for climate patterns across the world, of any specific increase in average temperature. This leaves scope for some imagination on the part of SF writers.

Perhaps the greatest uncertainty – and cause for worry – is over the issues of feedback and tipping points. Feedback concerns the threat that some consequences of increased temperature will themselves increase the rate of increase. One obvious example concerns the accelerating shrinkage in polar sea ice. The ice reflects 90 percent of the sun's rays and thus keeps temperatures down. As this disappears, more of the sea is exposed and this absorbs over 90 percent of the solar heat, which helps to explain why the Arctic is warming up faster than the rest of the world. Another example is the existence of large quantities of frozen methane in the ground within arctic regions. As the ground warms up large quantities are already being released into the atmosphere – and methane is itself a greenhouse gas. This could all result in a tipping point, when the self-reinforcing changes gather such momentum that they rapidly accelerate beyond recovery. Nothing like as rapidly as shown in the ludicrous film The Day After Tomorrow, in which temperatures plummet drastically in a matter of minutes, but significant change could happen over a period of decades rather than centuries.

The expected consequences of climate change can be grouped under several broad headings: weather fluctuations; temperature and rainfall patterns; sea level changes; and ocean acidification.

The weather fluctuations we can already see happening are the result of increased atmospheric instability as the temperature rises. That means we are likely to see more, and more violent, storms. It also means that we are likely to see annual temperature and rainfall records continuing to be broken (in both directions). This is, however, by far the least serious of the likely consequences.

Changes in regional temperature and rainfall patterns, and their consequences for agriculture, will be far more significant. These are extremely complex and cannot be predicted with any great confidence, but some general trends are becoming evident. One is that some currently fertile areas, mainly in continental interiors, will become a lot drier. We are already seeing a pattern of increased droughts, in Africa, Australia, China and the USA, where water sources are being used up faster than they are being replenished. This is likely to have a significant effect on agricultural production, since this is one of the major users of fresh water. In part compensation, certain other regions of the world which are now too cold for agriculture will become available. However, it takes a very long time to develop fertile soils suitable for agriculture, and the total area of agricultural land is likely to diminish significantly. Meanwhile, it is virtually certain (for demographic structural reasons – lots of young people in many parts of the world) that barring devastating epidemics, warfare or famine, the world's population will continue to rise until the middle of this century, up from the current 6.4 billion to around 9 billion, with obvious implications for the demand for food and living space – and CO2 production.

It has been suggested that some areas may paradoxically become cooler, at least for a while before the general increase in temperatures pulls them back up again. The best-known possible cause is the stopping of the Gulf Stream (also known as the North Atlantic Drift or the North Atlantic Current, which is part of the Atlantic meridional overturning circulation - AMOC) as a result of a surge of fresh water from melting polar ice. This currently keeps North-West Europe (including the UK) several degrees warmer than it would otherwise be, so the short-term impact of stopping it could be considerable. This was the trigger used for the sudden cooling so exaggerated in The Day after Tomorrow. Some studies have shown that the volume of flow of the Gulf Stream has already reduced by about 30% between 1957 and 2004, but the current view appears to be that a complete stoppage of the Gulf Stream is a less serious risk than previously thought.

The melting of ice brings me on to the third major concern, which is the changes in sea level. These are already happening, partly because the oceanic water expands as it warms up, but that effect is relatively small. It is also worth pointing out that the melting of ice already floating on the ocean (such as the Arctic Ocean ice cap centred on the North Pole, or floating ice sheets around Antarctica) has no direct effect on sea levels because the ice is already displacing water. The threat comes from the melting of ice which is currently on land. Some 90% of such ice covers Antarctica, another 9% is on Greenland, and the remaining 1% is in the form of glaciers and smaller ice caps scattered around the world.

To give an idea of the potential scale of the problem: if the West Antarctic Ice Shelf – WAIS – were to melt or slide into the ocean, global sea levels would rise by an average of about 5 metres. The disappearance of the Greenland ice would add 7 metres. If all ice went, the total rise in sea level would be around 70 metres (220-240 feet) but we don't need to worry about that – according to our current understanding, it would take many millennia, and in such extreme circumstances it is unlikely that humanity would be around to see it. For a more realistic threat, it is worth bearing in mind that sea levels were 3-6 metres higher during the last interglacial period although the global mean temperature was then only 1-2 degrees warmer than now. Current expectations are for an increase in temperature of at least 2 degrees by the end of this century, and it could be a couple of degrees more.

The conventional models of ice melting show that even the WAIS and Greenland ice would take millennia to melt. However, that assumes the ice would melt while still on land; a very slow process. It is now recognised that this isn't necessary, all it has to do is transfer to the ocean to provide the rise in sea level. There are signs that this is already happening, with the rate of movement of many glaciers showing a marked increase as they are lubricated by meltwater flowing underneath them. This could result in a much faster rate of increase of sea level, with an average rise of more than one metre by 2100 now being projected (about double that forecast in the IPCC report). Such a rise would have all sorts of unwelcome consequences for port cities and low-lying areas in which large numbers of people live and farm. There is, of course, a considerable lag between an increase in atmospheric temperatures and the melting of massively thick ice caps. What that means is that even if the average rise in temperature is held to just 2 degrees, the ice will continue to melt, and the sea level to rise, for centuries.

The most recent concern is ocean acidification, which is already happening. As temperatures increase, and the percentage of CO2 in the atmosphere continues to rise, more CO2 is absorbed by the ocean. This causes an increase in the acidity of the water, which potentially will have a serious effect on oceanic ecology as some creatures at the bottom of the food chain may find it impossible to cope. Coupled with world-wide over-fishing, this could result in fish disappearing from the human diet.

In conclusion: as the science firms up, the news concerning climate change keeps on getting worse in almost every respect. However, all is not (necessarily) lost. I will consider what might be done about this, which includes lots of SFnal ideas, in a future post.
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(This entry is cross-posted from my science-fiction & fantasy blog.)
 
Couple of years ago in the UK was a TV documentary about the effects of air pollution in the upper atmosphere shielding the Earth's surface from the sun and reflecting heat back into space.

This was first discovered after the World Trade Center Disaster (9/11) when aircraft were grounded across American, resulting in a suspected one degree increase in ground temperature.

World-wide efforts to reduce air pollution will reduce this shielding effect with the potential of comparable effects, not necessarily one percent from complete removal of air traffic, but some measurable portion thereof.

If you were thinking of a SF work on the theme of planetary warming (I call it "The Greenheat"), then an exploration of these kind of side-effects is worthy of consideration.

Imagine, using this as your starting point, the idealism of a new eco-technology designed to solve a problem, setting in motion a far greater danger.

:eek:
 
That's true, there are all sorts of conflicts within environmental concerns.

For instance, most environmentalists have always been opposed to nuclear power, but some are now advocating it as a lesser evil than producing more CO2.

Renewable energy such as wind and tidal power is welcomed by many environmentalists, but others are horrified by their effect on the natural environment.

The environmentalist movement tends to support the idea of local power generation, with each house having solar panels and so on, but such forms of power are erratic (i.e. the wind doesn't always blow) a problem best addressed by having huge, continent-spanning DC power grids linking large concentrations of wind, hydro and solar generators.

I'll be posting the second part of my tour around global warming this weekend.
 
What's irked me about so-called sustainable sources over nuclear is that you can't run a starship on wind power.

Without investment in vastly superior technologies we'll never keep up with human hunger for energy, and I don't mean the greed of the Americans, but the need to give everyone a dignified lifestyle in every corner of the world, and sustain the expansion of man's vision of the universe beyond the limited, flat-earth horizons dominating so much modern policy-making.

Long term I see the benefits of better, more efficient technologies, those that don't waste so much energy.

For example the lost of power in high tension cables between the generator and the consumer could be offset by looking into the efficiencies of superconductors. Or just move the power stations close enough to a community to benefit from combined heat and power methods; but who would tolerate a safe nuclear power station next door, when so many protesters and politicians insist they are so unsafe they have to be placed hundred of miles away?

Another campaign I've been developing aims to solve the issue of traffic congestion and air pollution with an, effectively, free for of personal urban transport. This uses existing technology, design and energy sources, but adds a very sophisticated financial model to the mix, reducing cost of investment to nought.

I understand the fear brought on by ignorance, but would like to see better design, better safety, better management over better protest campaigns.

:mad:
 
One of the fun things about reading - and writing - SF is the ability to play with all sorts of ideas for the future. The story I'm working on at the moment is set c.100 years into the future, in a changed world.

What's irked me about so-called sustainable sources over nuclear is that you can't run a starship on wind power.
You're forgetting this: Solar sail - Wikipedia although it would admittedly take a long time to get to another star!
 
...

The environmentalist movement tends to support the idea of local power generation, with each house having solar panels and so on, but such forms of power are erratic (i.e. the wind doesn't always blow) a problem best addressed by having huge, continent-spanning DC power grids linking large concentrations of wind, hydro and solar generators.

...
Unless the technology that allow for local power generation at the individual house changes to have an increased efficiency, there is no way of getting around still having some type of national grid. Most generation schemes do not provide for enough actual energy to power the house. Sure, we've all seen examples of certain houses where the entire roof was solar panels or houses on sprawling compounds with their own wind generators, but those types of systems are not plausible in urban & even most suburban environments.

I would love to be "off the grid" but I don't think my neighbors would really appreciate me turning the nearby soccer field into my own personal wind farm. If I went the solar panel route, the cost of outfitting the house with enough solar panels to be energy independent would never be recouped in our life time.
 
One of the fun things about reading - and writing - SF is the ability to play with all sorts of ideas for the future. The story I'm working on at the moment is set c.100 years into the future, in a changed world.


You're forgetting this: Solar sail - Wikipedia although it would admittedly take a long time to get to another star!


:smiley:

Yes, I know the argument - use solar sails. But as you have already appreciated - it's just not going to be fast enough for sensible journeys.

And would solar sails provide the internal power for the ship's functions, especially if you wanted a sensibly-sized crew (minimum ought to be 300 personnel for genetic health's sake if you're colonizing, or anticipating emergency colonization)?

A good power source ought to be small, fast, light, compact and sustainable. Nuclear is one such form, within certain limitations of what you define as sustainable (i.e., do you rely on a sun for your power or extract it from fuel for your own internal sun/fusion reactor?).

:smiley:
 
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