In Part 1, I established the basis of my predictions with an overview of biological and technological evolution. In Part 2, I described high-probability changes over the next decade that will serve as the foundation of much more complex and radical changes over longer timescales. Please review those entries, as this series is intended to build progressively. In Part 3, we magnify the scope of time to 100 years and examine systemic changes in civilization over the coming century.
Table of Contents
(Current part in bold)
I. The Energy History of Life (Part 1)
II. The Energy History of Humanity (Part 1)
III. The Next Decade (Part 2)
IV. The Next Century
V. The Next Millennium
VI. 10,000 Years
VII. 100,000 Years
VIII. Mark: One Million Years
Due to its short time-scale, Part 2 was largely a discussion of likely extrapolations from present trends, but as we zoom outward the larger-scale patterns discussed in Part 1 become increasingly relevant. So at this point it is useful to explicitly lay out those patterns:
Restatement of Assumptions:
1. The basis of life is energy.
2. The evolution of life is determined by the optimum dynamic balance of energy, water, and raw materials.
3. This dynamic balance forms the basis of the Root/Spore Cycle.
4. The Root/Spore Cycle is fractal, and occurs at all scales of life from individual organisms to entire ecosystems, and all scales of time from bacterial growth rates to geologic epochs.
The Root/Spore Cycle
1. A living system in an abundant environment will grow contiguously in all directions until it reaches the boundaries of abundance in any given direction. This condition is called Root.
2. Once a living system encounters the boundary of abundance, elements on the margins of that boundary will be iteratively selected for versatility and mobility until some become independent of the original system. This condition is called Spore.
3. Evolution within the Root environment leads to increasing specialization, density, diversity, and interdependence.
4. Evolution within the Spore environment leads to increasing mobility, generalization, geographic dispersal, and independence.
5. Once the Root environment reaches its contiguous boundaries in all directions, it achieves steady-state equilibrium and ceases to evolve internally - all subsequent change is driven by environmental changes or invasion by external forces.
6. Independent Spore persist as such until they reach a new pool of resources sufficient to spawn or conquer another Root condition.
7. Middle-case environments (neither abundant nor desolate) colonized by Spore will accelerate rather than dampen Spore evolution, outstripping earlier iterations of Spore from more abundant regions. This can continue iteratively to an arbitrary degree until Root-sufficient abundance is found.
I should state that this is not a scientifically rigorous model - it is simply a useful heuristic for understanding how living systems (including human civilization) evolve over large time scales. The following illustrated slideshow should more clearly demonstrate the principles involved. Keep in mind, though, that this is supposed to demonstrate an abstract principle, and that it applies just as well to human civilizations as to bacteria. A complete Root/Spore cycle is depicted:
Note that this cycle is recursive rather than recurrent: Each iteration changes the initial environment of the next iteration: I.e., Root at the end of one cycle is the Abundant environment at the beginning of the next, and Degenerate Root is the Harsh environment. Areas where Abundant and Degenerate Root interact would correspond to Middle-case in the next iteration of the cycle. In human history, these Middle-cases would usually be associated with peninsulas and the birth of Faster (N+1) Spore civilizations (e.g., Greece, Rome, Aztecs, etc.) - which is surprisingly well-indicated by the illustration, even though I made no conscious effort to show that.
Another principle we see is that colonized environments, regardless of their initial local abundances, can become either Root or Degenerate Root (i.e., location-bound due to scarcity) based on the context of their whole-system relationships. If the local system is too isolated, the N+1 Root will be Degenerate because resources will be consumed before renewable equilibrium can be achieved. Unfortunately, Degenerate Root does not bud Spore - there is no accessible surplus energy in the environment to form it, and that does not change until evolutions in the whole system make further iterations more successful.
This is critical because the global transition to renewable energy is the end of the current Root/Spore Cycle - a cycle that had begun with the invention of agriculture 10,000 years ago. Agriculturally abundant locations like the Nile formed the initial (N) Root, with places like the Levant and the Aegean forming the N-Spore. The above slideshow only depicts one Spore acceleration, but in fact it can accelerate several times (N+1, N+2, N+3, etc.) before achieving the next stable Root condition, and that is precisely what happened.
Powerful Spore civilizations arose in peninsulas and large island chains around the world at various times - Greece, Southern Mexico, Java, etc. - and their evolution, stagnation, or demise was determined by the local geography and the relative timing of their ascent. However, some arose under particularly auspicious conditions: In contrast to the rest of the world, Europe is practically a geographic step-ladder - a peninsula of peninsulas.
Greece, Italy, Iberia, Britain (effectively a peninsula), and Scandinavia are all major peninsulas of the European continent, which is itself a peninsula, so Spore iteration occurred much more quickly than in other parts of the world. This resulted not only in physical colonization of the globe by European powers, but in the transformation of existing cultures and societies along lines that first evolved in Europe: Most importantly, the scientific method and the ideal of progress.
Virtually no other civilization prior to Enlightenment Europe had conceived of systemic progress: The vast majority were concerned only with maintaining a changeless cycle of tradition, and those few who pursued some form of progress conceived of it only along the lines of military conquest or philosophical perfection - they had no means of rigorously penetrating the unknown and discovering new possibilities. As a result, they not only advanced slowly, but literally did not know what they were missing - there was only the Known and the Unknown Unknown, with no middle-ground that could be consistently expanded upon.
That all changed with the Scientific Revolution, and particularly with the widespread adoption of its most potent product: The heat engine. As a result, the world has been in a continuously-accelerating Spore state ever since, and the overwhelming driver of that acceleration has been fossil fuels - time-concentrated chemicals capable of fueling powerful heat engines, and thus radically mobilizing humanity. But the limits, political disadvantages, and hidden environmental costs of fossil fuels have become manifest, and humanity increasingly recognizes that energy renewability is a long-term necessity for civilization to continue.
We have, in other words, encountered a resource boundary. And according to the Root/Spore cycle, the response of N-Spore to encountering a boundary is for the system inside it to become either Root or Degenerate Root, and for that which becomes Root to bud N+1 Spore. What this means for the next century in practical terms is that humanity's transition to renewability will form three somewhat-overlapping tracks of development:
1. Areas with an optimum balance of renewable energy, water, and raw materials will form the basis of N+1 Root: Rich, increasingly diverse, and economically interconnected societies that grow continuously by climbing their energy pathways - i.e., by accessing the energy more directly, and utilizing it more efficiently.
2. Areas with extreme resource-imbalances - such as having plenty of energy, but having to spend most of it accessing water and raw materials - or those that are poor overall in renewable energy will form Degenerate Root: Societies that achieve sustainability, but have extremely simple economies with little surplus energy remaining for diversification, growth, or change. Societies that fail to achieve sustainability at all will simply shrivel until they do, or become dependent on those who do.
3. N+1 Spore: Given that the scope of the system is now the entire planet Earth, the Spore-budding boundary is (not surprisingly) space. Economies that grow from it will be dynamic, unprecedentedly mobile, and generalized by necessity. However, since it is the first iteration to leave Earth, it will do so slowly, expensively, and in small numbers.
Based on the Root/Spore Cycle and the processes begun over the coming decade, my view of the next century may not be surprising at first glance: Global energy infrastructure will be entirely renewable, with the vast majority of generation being wind and solar - as these are the most abundant, cheaply harvested, and easily-accessible options. They are also the most fertile for technological advancement due to modularity and variety of potential approaches.
As noted in Part 2, implementation of wind power is likely to temporarily exceed that of solar due to regional considerations - i.e., being more attractive to Northern Europe, and both the Midwestern and Northeastern regions of the United States - as well as being more controllable by oligopolous energy interests looking to survive the transition to renewability.
However, a couple of factors guarantee that solar will accelerate beyond wind and ultimately become overwhelmingly dominant in this century: (1) As noted in the above graphic (courtesy of Wikimedia), the sheer size of currently accessible solar energy far outweighs that of wind; and (2) the growth in accessible solar energy will far exceed wind due to the much greater scalability of photovoltaics - i.e., PV solar can be scaled from microscopic components up to arbitrarily large panels and fields, while wind has much harder practical limits. In fact, solar will eventually eliminate wind entirely as a significant source of energy, but not by 2110.
We will also see the outcomes of two other significant competitions: Utility-scale renewable energy vs. distributed generation, and PV solar vs. solar thermal. In both cases, the side that initially dominates due to affinity toward the existing industrial base will ultimately fall behind and be defeated by the side that is more modular, scalable, and adaptable. Utilities will dominate the renewable energy landscape for the next few decades, but small-scale power systems applicable to individual homes and businesses will experience radical growth and rapid cycles of innovation analogous to the IT industry while utility companies adapt much more slowly. Ultimately distributed options will dominate, and utilities will be progressively phased out in favor of scaled versions of distributed technology.
In the competition between PV and solar thermal, the latter will initially be dominant because it generates electricity with a heat engine - a technology that is virtually perfected, cheap, and well-understood, but has relatively little room for additional innovation. This will occur in tandem with the dominance of utilities, since solar thermal is ideal for utility-scale solar generation and is much less practical on smaller scales (with solar water heaters being a minor exception).
Photovoltaics, on the other hand, are a far newer technology that has already spawned a multitude of considerably different approaches and an ever-thicker backlog of laboratory innovation. They are also arbitrarily scalable, arbitrarily modular, have no (intrinsic) moving parts, and represent a more direct pathway from solar energy to electricity than one involving a heat engine. At some point we will see that laboratory backlog explode into realization, commencing a process of radical growth in the PV industry and major expansions in the diversity, adaptability, efficiency, and cheapness of the technology.
The PV/ST competition will parallel another major change in technology: Namely, the death of the heat engine. I am, of course, exaggerating - we will still find uses for heat engines to some extent, such as in geothermal plants (which will be a minor component of renewable infrastructure) - but they will cease to play any major role in energy generation or transportation. Photovoltaics will progress to the point of making solar thermal obsolete, and both electricity storage and rapid-charging technology will advance to the point that the internal combustion engine - even with innovations making it significantly more efficient - will not be able to compete.
This means that, for the first time in history, human civilization will be directly powered by the Sun - we will have made a collective evolutionary leap as significant as the evolution of photosynthesis, and formed the basis of an enduring (and continuously evolving) human ecology. The long-term implications of this are rather astounding, but over the next century humanity will still be in the initial stages of forming a standard energy framework based on PV solar: There will still be a significant level of wind power, and some geothermal plants in seismically active regions. Still, by 2110, humanity will not even have come close to realizing the limits of Earth-based renewable energy, so we can expect centuries of additional growth and complexification to follow as the Root expands into its new energy environment.
Although energy will become radically decentralized, with PV being generally incorporated into building materials and structural surfaces, we will also see the densest urban environments begin to act cooperatively to most effectively harness solar energy. Some skyscraper and high-rise owners will find their property values harmed by having sub-optimal views of the Sun, forcing their tenants to rely more on the grid for electricity, and groups of such buildings may cooperate to build solar canopies above them. This, in turn, may result in other buildings losing solar flux and complaining, causing city officials to regulate the process and ultimately construct municipal solar canopies over the downtown core.
Transparent or arbitrarily tinted solar panels already exist in the laboratory, so a solar canopy over part of a city wouldn't turn it into a dark, foreboding Blade Runner environment - the light might look virtually the same, or might be polarized in different places at different times for artistic effect or to absorb specific wavelengths.
The entire process of urban zoning and building regulation will change to allow for fair (or at least politically advantageous) access to the Sun, altering not only the look and shape of downtown skyscrapers, but how they're constructed in relation to each other. Such canopies could double as systems for capturing and channeling rainwater, making them just as useful when the Sun is hidden or has set. Even with the first municipal PV canopies going up - perhaps over Manhattan, Tokyo, and Beijing - people probably won't notice the increasingly striking similarity between how their cities are shaping up and how rainforest ecologies evolve. The Root will not quite be obvious yet, but civil engineering will become a lot more complex and faceted.
Climate change, unfortunately, will remain a major and increasingly obtrusive problem even with the transition to full renewability. Greenhouse gases stored in the environment will continue to be released by the self-reinforcing cycle of global warming even after humanity has zeroed its emissions or even gone negative, so there are likely to be regional disruptions, sea-level rises, and growing pressure on both water and food supplies in some parts of the world. This may cause some degree of mass-migration, although I doubt it will occur rapidly enough, or on a large-enough scale in one event to majorly disrupt global civilization - population will continue to increase. Some countries, however, may become destabilized having to manage too large a number of foreign or internal refugees.
The resulting economic pressures will further drive resource-localization, energy decentralization, and systemic efficiency, causing some areas to lose economic viability while others gain it. With the dampening of high-mass global trade in favor of local resource-utilization, this will spawn the kernel of something I call General Technology (GT) - the ability to sustain a prosperous local economy given an arbitrary set of resources above an absolute minimum.
In other words, rather than buying a product from abroad, or buying resources from abroad to build the product, you find a way to use the resources you have to build what you want. GT will not be realized in the coming century, but its economic basis will likely occur in that time period due both to localization and Spore influence from space-based activities (see: In-Situ Resource Utilization).
A key component of rigorous GT is the ability to practically break down or manufacture atomic elements, which requires practical fusion energy - something I do not think will be achieved in this century. I do think working fusion reactors that release more energy than they consume will be achieved, but are likely to remain uneconomical within the 100-year timeframe: They will likely cost more to build and maintain than the value of the energy they generate, and will not remotely have been evolved to the point of being used as efficient elemental-recyclers. So energy-generating fusion will exist in successful pilot projects, but not as part of the economy.
In lieu of fusion-based GT, the aforementioned pressures will yield iteratively greater focus on desalinized seawater as the basis of humanity's water supply, and large-scale water pipelines will be constructed to distribute it inland from coasts. This will initially serve to mitigate the effects of climate change on agriculture, although food and water shocks are still likely to occur with the potential for starvation and dehydration in affected areas. But eventually the water distribution system will become scaled and efficient enough that it will substantially increase agricultural output and climate-robustness. In particular, I would expect to see these systems have the most radical impact in Australia, the Middle East, and California, but they are likely to become widespread everywhere that rainfall is not abundant.
As you may already be aware, renewable energy is not 100% free of pollution: It emits heat that further drives global warming. One unfortunate result of global adoption of solar energy will be that the albedo (i.e., reflectivity) of the Earth will change: Some of the energy that would have been reflected back into space is instead absorbed, utilized for electricity, and emitted as infrared radiation that the atmosphere traps. The fact that glaciers and snowpacks are disappearing - highly reflective, white surfaces - only exacerbates the effect.
Fortunately the solution is straightforward, and much easier to implement than renewable energy: Replace and exceed the lost reflectivity. In other words, complement solar panels in one area with mirrors in another so that the Earth is not taking in net energy - i.e., no longer warming. Reflective surfaces would probably have to be much larger than the total solar-harvesting area in order to counter past warming and reverse course, but it can be done. Given its simplicity, I strongly suspect the process of reversing global warming through albedo-manipulation will be begun in the coming century, although it will take considerably longer to achieve its objectives.
As for Spore, the initial movement into space will not be based on energy: Although it's abundant in the inner solar system, it will still be much cheaper to build more solar capacity on the terrestrial surface than to construct space-based solar arrays. Thus the destinations and structure of spaceward expansion will not depend on energy, but on the two secondary requirements: Water and raw materials.
There aren't much of either accessible inside the solar orbit of Earth, so the first iteration of Spore will expand away from the Sun - i.e., its destinations outside of the Earth-Moon system (which I expect to be teeming by 2110) will overwhelmingly be Mars and asteroids. The Sun is still powerful enough at these locations for solar energy to be practical, but the environment is cold enough to accumulate volatiles (i.e., water ice) that can be used not only for water itself, but to generate rocket fuel.
While I do expect initial settlements on the Moon to precede Mars exploration, the first major expansions on both will proceed simultaneously due to the VASIMR rocket engine - an ion propulsion system that could reduce transit time to Mars from 6 months to 6 weeks. A scaled prototype is scheduled to fly on the International Space Station as a thruster, but the firm developing it - Ad Astra Rocket Company - has planned for the Mars application from the beginning. It will likely take several decades to scale the technology for crewed applications and develop a sufficient power source (e.g., a weightless nuclear reactor), but since the time-scale of this entry is 100 years, I am positing that VASIMR will be operational and in widescale use.
Because of how VASIMR functions, it reduces the time to Mars by a much larger factor than it reduces time to the Moon, so in essence it will serve an equalizing function for the two destinations. Still, I do expect colonization of the Moon to be much more rapid in the inclusive time period than Mars, since it's so much easier to get there - and especially so much easier to get back, which is critical for any sort of business enterprise that depends on returning material to Earth. VASIMR will also make visits to the Main Asteroid Belt feasible, although obviously a more lengthy and involved trip than Mars. I will not speculate on the exact course of exploration and settlement on asteroids in this century, because we know too little about them and their potential.
There are some enthusiasts of the space elevator concept who believe that it will only be a matter of decades before we can achieve it, but I am skeptical. Even when materials science produces the carbon nanotubes needed to meet the strength requirements of a space elevator in sufficient volume and quality to theoretically build one, it will still be decades more before we know how to build one, and decades more still before we actually do - and even then it will be a small prototype that likely fails, serving only to educate people about the extreme complexities involved. Space elevators are inevitable, but they will not be implemented in this century.
However, I can say that the radical increase in material strength due to the advent of such things as carbon nanotubes, graphenes, and other nanomaterials likely means that our cities are going to get A LOT taller over the next century. Particularly the carbon-based nanomaterials will, I think, ultimately be cheaper and more energy-efficient to produce in bulk than steel, in which case the cost of building skyscrapers will fall through the floor as substantially as their height and safety increase. We probably will not see a space elevator, but I don't think 5-kilometer buildings are out of the question over this time scale - the world's current tallest building is 0.8 kilometers. This is also not an essential prediction, just something I think will happen.
In summation, the coming century will be the transitional period marking the end of the Root/Spore cycle that began with the development of agriculture 10,000 years ago, and will give birth to a new Root - global civilization marked by local resource utilization and PV solar energy - and new Spore - initial settlement of the solar system region between Earth and the Main Asteroid Belt, primarily involving the Moon and Mars.