Wednesday, January 16, 2008

Climate Change, Tipping Points, Feedback and the North

This has been amended slightly from another blog - Triple Pundit, as linked to ENN News. Definitely worth a read, as are the embeded links.

Andrew Burger posted two excellent articles on 3P here and here regarding the general state of research, science, and the modeling of climate change. I refer you to those article for a good foundation. There are also a variety of excellent resources on the web, some of which Andrew cites in his posts, and other worthwhile sources such as RealClimate, The National Academy of Sciences, USCap (an alliance of business and environmental research and advocacy groups), and the American Association for the Advancement of Science.

One of the best sources for getting a grasp on science in general and climate change in particular is the video series from “WonderingMind42”. If you are at all concerned or interested in climate change, even if (especially if) you harbour scepticism regarding the efficacy of the science and are bothered by words like “consensus” - see these great videos. Look especially for the “Nature of Science” videos to get a great overview of the process of science and a guideline to assessing the credibility of sources.

Of course, not everyone agrees with the peer-reviewed science represented in the aforementioned sources and so aptly explained in Andrew’s posts. James Inhofe has released his report from 400 “prominent” scientists refuting the reality of anthropologic climate change. Many disagree with the “James Gang” — but you should make up your own mind.

Good scientific theories are continually challenged as a means of making them stronger.

I’d like to follow up in this post regarding tipping points, a look at 2007, and why I expect to be very cold next month as I try to learn more about climate change.

Positive Feedback Loops that Can’t Just be “Turned Down”

In the WonderingMind videos there is a detailed discussion of positive feedback loops and tipping points. His method of demonstration does a great job showing the nature of thresholds and positive feedback, and relates directly to my own practical experience as well.

We’ve all seen the bit in TV shows and movies where some nervous (or guilty) individual steps tentatively up to a microphone, taps it (something you should never do incidentally), and causes the sound system to emit an ear-piercing screech. We all know about “feedback” in live sound systems, but did we ever relate that phenomenon to climate change?

Despite the fact that the typical scene I just described demonstrates an unrealistically low feedback threshold in most cases (unless you’re inexperienced setting up sound systems), it is an excellent example of a system reaching a threshold or “tipping point”, after which the system enters an accelerating and largely uncontrollable positive feedback loop — Screech!

Two salient points here are 1) that the exact location in the system dynamics of a tipping point or threshold, after which the system becomes unstable, is unknown until that threshold has already been crossed and 2) once crossed things get crazy and happen fast.

Even running a sound system you are very familiar with, in a room worked in for years, with sound sources that, more or less, remain the same, you can never be fully confident that they will not unexpectedly run the system into feedback.

Certainly with modern tools and experience, it is possible to have a good estimate of where that tipping points is, and thus keep the system from reaching that point most of the time. But not always. Every so often a “mic will ring” and — oops — I’ve crossed a threshold and the system is out of my control until I turn the offending sound source down.

Sound systems, acoustics, and the physics of sound can be complex subjects, but they are obviously child’s play in relation to understanding the nature of our climate. I can just turn down a sound system, but once a system in our climate has reached its tipping point, something we won’t know until it is passed, the “steady-state” of the system is replaced with accelerating positive feedback loops of increasing instability that cannot simply be “turned down” and the effects of which are highly unpredictable.

And it is not always apparent that the tipping point has been reached even if we’ve reached it. In terms of global averages, last year was the second warmest year on record (behind 2005). However, in northern latitudes temperatures are increasing much more rapidly than the global average and there are indications that 2007 represents a tipping point in the far north, with arctic ice and permafrost melt.

Permafrost and peatland are an area of concern for scientists studying the climate. Alaskans are increasingly confronted with shifting land and damaged housing and infrastructure from melting permafrost. Of even more significant concern is the vast stores of methane and carbon in the permafrost of the subarctic and arctic regions and what happens when it melts, releasing that carbon and methane into the atmosphere, further warming the climate, accelerating the melting ice and permafrost, releasing more carbon and methane, warming the atmosphere even more”¦ Screech!

Dr. Peter Kershaw studies the subarctic region known as the “continental treeline”, a region where permafrost underlies the landscape, and has established several study plots throughout the Hudson Bay region near Churchill, Manitoba. Kershaw’s goal is to quantify the environmental conditions present in this region of permafrost and peatland landforms and monitor the changes in order to best asses the effects climate change has on these landforms, and how those changes in turn effect ongoing climate change.

Many see 2007 as a tipping point. It is something, in one way or another, everybody that contributes is talking about — how to create a sustainable and prosperous world. In terms of climate change, potential environmental tipping points possibly are already crossed as climate models for arctic sea ice are proven wrong — and conservative. But also where public, corporate, and even government awareness has reached it’s own tipping point — where positive feedback is good thing.

And thus, 2007 may be the point where the reasonable and responsible debate moves forward.

Climate change is here. Human activity is a major contributing factor. At some point, we need to respectfully choose to ignore those that refuse to act reasonably in the face of the evidence. They may think and act as they choose, of course, but we do not need to give it much credence until there is real, falsifiable evidence to warrant it.

Therefore, the debate must be: What do we do about it?

Readers of this information are among the smart innovators, visionary business leaders and solution-minded individuals that can help answer that fundamental question.

And so I say to you, to me, to all of us — let’s get after it.

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