April 30, 2003

SARS and 6 Degrees

We probably dodged the bullet on this one but it provides a vivid illustration of the level of our interconnection and the vulnerability that might present. The SARS story broke right around the time that the US invaded Iraq and as riveting as the embedded reporting was, I was playing close attention to the scroll at the bottom of the screen and wondering about the priorities of the news media (but that is a different rant).

SARS seems to have had it origin in Guangzhou. It is likely to be a coronavirus and it is possible that close contact between humans and animals in Guangzhou allowed the virus to jump from animals to humans.

What is fascinating and scary about SARS is how fast and widely it spread. The speed of spreading is due to the biology of humans and the virus. The virus could survive for fairly long periods outside of the human body and is spread in droplets related to the coughing and other symptoms of the disease. In addition it seems that some people are extremely efficient at spreading the disease.

The geography of the spreading is primarily related to the extent that humans move around the globe. It has been observed many times that replacing sea voyages with air travel allows people to get from point A to point B much more rapidly than the incubation period of the disease. This allows the pathogen to mix well around the globe.

The reason I am writing about this today is an article in the New York Times. It seems that a case of SARS has been identified in the very exclusive enclave that houses the senior leadership of the Communist party in China. To me this highlights the interconnection elements of the epidemic.

Think of SARS as a tracer. There is a path from any new case to an old case. Thus there is a path from the elite of Zhongnanhai to the outlaws of Guangzhou. More impressive is that there are fairly short paths from China to all of the developed economies in the northern hemisphere and many of the better developed economies in the southern hemisphere. All of this illustrates the importance of the ideas around 6 degrees of separation.

It is especially sobering to imagine the what it would like if instead of about 6% mortality, SARS had 25% mortality and rather than superspreaders being rare, they were the norm. If this were the case we would probably recognize the problem faster than we did this time round, but given our experience in Toronto, it is not hard to imagine falling behind the curve and not being able to recover.

April 29, 2003

Enter Democracy

I ended last night with a thought experiment to meant to twist your brain regarding the kinds of policies we will need to develop if we are going to move toward something like sustainability (which is another idea we will need to come back to). Implicit in whatever sustainability is the notion/objective that all of Earth’s (human?) inhabitants have an improving quality of life (what ever that means). I proposed that we imagine the kinds of infrastructure and processes we will need to manage Earth systems that have century time scales.

The best example, that I am aware of anyway, of a policy document that has the requisite time scale to manage things like the concentration of CO2 in the atmosphere is the Constitution of the United States. Roughly that document sets out a set of over arching objectives (life, liberty and the pursuit of happiness) and an infrastructure and procedural frame to facilitate moving toward those objectives. It leaves tremendous flexibility regarding exactly how those objectives will be reached. That flexibility allows us to learn-by-doing.

While there is flexibility in the details of implementation, the framework laid out by the Constitution is difficulty to modify. Thus in the language of time scales, the framework of the Constitution has a longer time scale than the processes it guides.

So what is the point with respect to the title of this entry? The point is that if we are going to move toward some set of objectives, we not only have to figure out how to move, but we also have to figure out where we hope to end up and how to know if we are moving in the right direction. Democracy is related to identifying where we want to end up.

Our early framers had a bit of an advantage over our current situation. They could reasonably focus on fairly restricted geographic locale. They could reasonably assume unlimited natural resources. And perhaps most importantly, while their ideas about who exactly was "created equal" were pretty expansive for the time, it was still a pretty homogeneous set. These things made it fairly straight forward for them to agree on a set of "self-evident" postulates and a set of related objectives for their new society.

Shear numbers ensure that no such homogeneous, representative decision making body can be assembled today over the space and time scales I am talking about. Thus one of the great challenges we face as we move forward is how to deal with heterogeneity in our populations and in our geography.

Let me be clear, I am not calling for a single Planetary Constitution that is a simple metaphor to the US version. I am (at least for the moment) arguing that we need to invent or identify some set of processes that will provide a framework to guide democratic processes on scales larger than the nation state. This infrastructure will need to rooted in some evolved form of democratic principles and have time scales that are long compared to many of the natural and social processes we are trying to protect.

April 28, 2003

Time Scales


Yesterday I wrote a short introduction to spatial scales. Today I will write briefly about time scales.


Some timescales of interest:

  • Decision making - minutes to months
  • Attention span - about 15 minutes
  • Seasons - 3-6 months depending on latitute and other geographic factors
  • Career span - 40 years
  • Lifetime of Carbon in the atmosphere - hard to say, but a century or two is a useful approximation
  • Age of the United States and the time since oxygen was discovered - 250 years
  • Time since end of the last glacial period and the invention of agriculture - 10,000 years
  • Age of humans - 1million (1e6) years
  • Age of Earth - 4.5e9 years


    15 minutes is about 3e-5 years; thus if we just take the times outlined above and restrict our attention to human time scales, the time scales of interest span somewhere between 9 and 11 orders of magnitude. This is a huge range. Even if we decide not to worry about times longer than the age of the United States, we still have management time scales that range over 6-7 orders of magnitude.


    Let me give a concrete example. There is much concern about about the rapidly increasing concentration of CO2 in the atmosphere. It is pretty clear that most of this increase is due to the burning of fossil fuels due to rapid industrialization over the last couple of centuries. Carbon that was put into the atmosphere at the beginning of the industrial revolution has only recently cycled out of the system. Carbon that we are emitting now from our energy production and transporation systems will continue to influence the heat budget of our climate for about 2 centuries. Thus actions that we take to mitigate the impact of CO2 emissions will not have their strongest impacts for at least several decades.


    One more point on time. Think about the amont of learning and technological advance we have seen since oxygen was discovered sometime in the late 18th century. Think about what we will learn and how things will change over a comperable time into the future. Now try to imagine what kinds of policies and practices we will need in order to accomplish long-term human well being.

  • April 27, 2003

    On Scale (first words)


    Understanding scale and scaling is crucial to the task of managing our interactions with Earth systems. There are two kinds of scale that must be considered - space and time. I will consider space first and time in a future installment.

    "Think Global, Act Local" recognizes two important scales. At the large end is the scale of the planet. Assuming that the radius of Earth is 6000 kilometers, we can put a number on this planetary scale that is on the order of Earth's circumference - 2*pi*radius or about 40,000km. Note that considering the atmosphere does nothing to change this number as 99% of the atmosphere's mass is contained in the first 40km of altitude (my rounding does not see this). (More on the structure of the atmosphere)

    Begin Aside As a physical scientist, I am going to work in the metric system. A useful conversion from km to mi is 2/3 (my rough value for Earth's radius is equivalent to 4000 miles, which yields a planetary scale of 25,000mi). Note also that as a I am trying to make points I am likely to be rough with numbers, but I will try to keep track of rounding to keep things close). So pi might become simply 3, pi squared will definitely be 10 (with a nod to Ms. King). The radius of a sphere of equal volume to Earth is 6371km. 6000 is close enough for me (do the math and round to a nice number). End Aside

    At the small end is the local. This is not quite so clean in terms of a number. In the context of the bumper sticker I interpret it to imply the level of a community which I would scale at about 1 km. But local can also refer to one's own behavior which in its most intimate sense has a scale of about 0.001km (about 1m).

    Thus in terms of space we have scales that range from about 1e-3 to about 1e4 (if you don't recognize this notation, see next aside), or about 7 orders of magnitude. I will have plenty to say about the scales in between the global and the local in future posts.

    Begin Aside I am going to use the "e" format for scientific notation. Thus 1e4 is 1 times 10 raised to the 4th power or 10,000. When the number following the "e" is negative, the decimal point moves to the left; thus 1e-3 becomes 0.001. End Aside

    It is perhaps trite in this day and age to observe that human numbers and technological capacity have become significant factors in the functioning of Earth systems. In particular Herbert Simon's artificial now rivals the natural in determining the evolution of our planet's future.

    I saw a book today by the founder of Greenpeace. The book is called Thermageddon and, based on the jacket blurbs it argues that Earth is on the verge of an irreversible transition due to the ongoing increase in CO2 concentration in our atmosphere. The possiblility of such transition is real and we should do everything we can to avoid them, but in recognizing their possibliltity, we should also consider how we might manage the risk. Planetary Management is the effort to develop and implement managment structures that recognize the spatial and temporatl scales of human activities in relation to the functioningn of our planet.