I want to discuss a couple of key ideas which I think are important to the climate discussion.
- Mankind is producing a monotonically increasing driver into the climate system, ~2-3 ppm/year of additional CO2, due to industrialization, which is an unusual forcing function. Most natural systems produce either cyclical (like solar irradiation) or aperiodic (like volcanoes) forcing functions, which provoke complex dynamic responses in the climate system, but ones that tend to return to previous states, over long time frames.
- The increasing interdependence of mankind on the geographic stability of weather, driven by climate, particularly in food production and water resources, but also reflected in expected sea levels, severity of storms, etc.
The first cause is relentlessly driving our climate from the relatively stable plateau that civilization arose in to a new state that will potentially be very different from the current one. And the second effect is that we have created a system that, relying on this relative stability, and through a lot of fine tuning and optimization, is able to maintain a population in excess of 7 Billion (on the way to 10 Billion) long-lived humans on the earth.
So, arguments that rely on the undeniably true fact that the earth's climate has varied more in the past than it is doing now are truly irrelevant to the experience to which we are about to subject 7+ billion humans. We live increasingly in fixed cities, mostly near the sea, incredibly interdependent on a complex web of relationships for food, water, economic viability, physical health, and many more factors. The experiences of nomadic tribes of humans or pre-humans in some previous era has virtually no relationship to now.
It is a fact of most dynamic systems that the efficient states are near the line of instability - they are more efficient in the use of resources, but less able to withstand deviations in underlying conditions. Included in these underlying conditions are our assumptions about them, which, seemingly as a part of human nature, we take as steady and non-changing (it seems to only take a few generations to once again build in low lying zones, after the previous flood event, or below the volcano).
As we push ourselves closer to the instability margin in a variety of areas, always looking for optimal efficiency, and towards states that are very efficient and fine-tuned to local conditions, we begin to expose all the many hidden assumptions that we so rely on.
An example of pushing towards these edges is an idea called the "Age of Hyperspecialization" The Big Idea: The Age of Hyperspecialization. As the efficiency benefits of parallel development, sub-goal competition, and knowledge matching play out, we, as a global society, become dependent on these new efficiencies. We build them into the market, into our expectations for costs and quality, without analyzing the assumptions (instant and constant communication, global movement of goods and education, relative political stability in key areas, and basic living standards,...) that go into exploiting the efficiency gains.
So when we threaten the underlying stability, be it militarily, politically, economically, or, more universally, with climate, we really need to understand how that might affect the systems we have grown to rely on.
This is old thinking with regards to certain commodities, like oil, as we can see from the size and scope of the American military complex. And, in fact, there is a huge concern among military strategists regarding climate change and how it can substantially, and perhaps irrevocably, shift the underlying base on which civilization's stability rests.
We are not talking about the necessity of a huge decrease in food production and fresh water supply - but rather about a reduction in the rate of increase in production of these key commodities. With every technological breakthrough and efficiency increase, we ratchet up our expectations for more. And if we don't get it, great suffering can result, in the forms of recessions, political unrest and revolution, or worse.
Now imagine a sustained, negative effect on our ability to produce more and more, faster and faster, due to fundamental shifts in rainfall, food growing regions and seasons, natural disaster locations and severity - these can make our man-made financial recessions look like "blips on the radar".
In many parts of the world, especially the third of humanity that resides in China and India, there is a direct relationship between GDP growth and energy use. So what happens while trying to pull 1.5 Billion people out of abject poverty with this relationship in place? Even if the average energy density in those two countries is currently less than 25% of the US, and even if it is only projected to reach 50%? The math tells us that, without very substantial, almost revolutionary, modifications to conventional, cost effective energy production methods (both electricity and transportation fuels), we will face a very real adjustment to our climatic steady state, with all the ramifications that will have upon our finely-tuned, complexly integrated global systems.
Another example of the unprecedented interdependence in today's global economy is the effect that the sovereign debt crisis in Greece, a small economy and population, can have on the global economy. If chaos can be inflicted on the world's markets, causing real harm to people's everyday lives, from an artificially created financial crisis in a small country, imagine what havoc actual crop shortfalls and shifting weather patterns could cause.
It is telling that consumer confidence is a key economic indicator in the modern world, and that small variations in it can send shock waves through an increasingly global supply chain of manufacturing and services. The run on the banks in 1929 was primarily driven by panic, resulting in coordinated activity amongst a large population. The working assumption built into our financial systems, in order to drive efficiency and scale, is that there would never be that level of correlation of actions, allowing the system to function with only a few percent of capital in reserve. In steady state conditions, with relatively small excursions, this works, and is very effective at getting the most value out of capital. In extreme cases, the underlying assumption does not hold, and all hell breaks loose.
Imagine the fundamental and long lived (think hundreds of years) shifting of underlying assumptions - about the California valley's ability to grow produce, about the sea levels in low lying areas throughout the world, about the typical severity (he "100 year storm") of natural disasters that we are actually prepared for, and you begin to see the absolute necessity to insure ourselves against even the possibility of this, or at least attempting to mitigate the severity of the climactic shift that we are driving.
Being very dependent on fixed areas to produce very large percentages of food works really well in stable times. However, just move the jet stream 200, or even 100 miles north or south as it crosses California, and the opportunity for massive disruption of production efficiency of the Central Valley is almost assured. Even a few percent decrease in production can play havoc with food prices around the world. Imagine the same effect in the midwest (as we are seeing this year with corn], and watch the reverberations cycle throughout the global system.
Will these things cause humanity to go extinct? Of course not. Can it cause a lot of pain for a lot of people? Absolutely. We need to focus on insuring against that pain.
There is a self correction mechanism here, of course, as there is with most large scale systems. There are several involuntary ways for humanity to reduce GHG emissions - one has just happened, to a small degree - the financial crisis and associated recessions. A long, deep, global recession will certainly reduce emission, at least for the short term.
The other obvious way, of course, is to have many less humans on the planet. This can happen in several ways, but the most likely is probably related to communicable disease, as that vector exists already, has some correlation to both temperature and water incursion, and has the scale to be able to affect a substantial portion of the population.
I would hope no one is interested in this type of solution. It would be much more rational, as a species, to invest a few percent of global GDP into a climate insurance fund, and reduce this risk as soon as possible.