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Climate Change 2007: Credible Science, Tipping Points, Feedback, and the Great North

| Monday January 14th, 2008 | 4 Comments

An Arctic SunsetAndrew 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”, mentioned previously on this blog. If you are at all concerned or interested in climate change, even if (especially if) you harbor skepticism regarding the efficacy of the science and are bothered by words like “consensus” I can’t recommend these videos highly enough. 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. (here’s a hint, individual bloggers are toward the bottom of the list – more on that in a moment)

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. I make no bones about what I think of 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.

This is something I deal with almost every day. Even running a sound system I am very familiar with, in a room I’ve worked in for years, with sound sources that, more or less, remain the same, I can never be fully confident that I will not unexpectedly run the system into feedback.

Certainly with modern tools and experience, I am able 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.

Climate change in the north - skating on thin iceAnd 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.

Through the Earthwatch Institute, I will have the opportunity next month of participating in a research expedition assisting Kershaw in his ongoing work in the region.

I see 2007 as a tipping point. It is something, in one way or another, everybody that contributes to this blog is talking about – how to create a sustainable and prosperous world. In terms of climate change, I see potential environmental tipping points possibly 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, I also see 2007 as 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 blog 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.

 

Tom Schueneman writes on environmental issues to GlobalWarmingisReal.com and Hugg.ca. He also publishes MarkTwainBlog.org, ThomasPaineBlog.org, and AlbertEinsteinBlog.org. His humorous account of life as a sound engineer is known as the Soundman Chronicles.

 

 

 

 

 

  

 


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  • John Howard

    The positive-feedback, tipping point argument is an analogy, not a fact. Positive feedbacks are quite rare in the natural sciences. Negative feedback is the norm. The older the system, the truer this becomes. The climate is a very old system. Claiming to know that positive-feedback tipping points are approaching in climate science is pure bluff and science fiction. They are counter intuitive and counter factual.
    The Anthropogenic Global Warming theory is a dying theory. The tipping point scare is the latest attempt to save it. Essentially the argument says, “Maybe the facts don’t support us now, but they will suddenly tip in our direction and then we will be right. Just you wait!”
    The tipping point that has come in 2007 is that AGW is no longer taken seriously by enough knowledgable people for it to survive as a viable theory.

  • http://www.globalwarmingisreal.com/blog Tom

    Sure thing John – thanks for the comment.

  • John Howard

    Sure thing Tom – you’re welcome.

  • CobblyWorlds

    I agree Tom,
    2007 will probably be notable for some time. In particular due to the events in the Arctic.
    The Potsdam Institute of Physics already consider the Arctic ice cap to have tipped. http://www.pik-potsdam.de/infodesk/tipping-points
    For what it’s worth I agree, we are almost certainly in a transitional period to a seasonally ice free Arctic, with a much thinner ice cap through the winter (although the winter extent will very probably remain large). As to how fast this transition will be: Models for the IPCC showed seasonally ice free at the end of the 21st century. But this is generally agreed to be wrong. Most like Serreze point to 2030, Wadhams points to before 2020, and Maslowski between 2010 and 2015 – which can be taken as the lower bounding. So we have any time between 2015-2030 as the earliest first occurrence of summer ice free Arctic.
    Given the role of the Arctic in Northern Hemisphere climate, e.g. jetstream position, this is something we need to watch. However although there is reason to expect climate impacts from a severe reduction in Arctic ice, it remains unclear what the exact impacts will be. I am happy to be on record, both here and elsewhere, that we will see IPCC regional change projections over-run by the shifts in precipitation patterns due to the Arctic changes. Some areas may benefit, some will not, overall it’s a worrying situation with >6bn mouths to feed.
    I have to strongly disagree with John Howard when he says “Negative feedback is the norm. The older the system, the truer this becomes. The climate is a very old system.”
    That is not correct. The Earth is not in a reducing energy state like Mars, the bisosphere has an active and ongoing role in our planet.
    The amounts and potentials of feedback actually vary with time. For example leading into an ice age the build up of ice sheets is a slow process (you can only accumulate a year’s ice from snow as a result of a year’s snow fall surviving a year). However leading out of an ice age you can lose more than a year’s accumulation of glacial ice by melt processes. Hence the asymetry in the time-axis, e.g. http://www.brighton73.freeserve.co.uk/gw/paleo/400000yrfig.htm
    It is clear that the direction of change impacts the nature of the feedback, and it’s strength.
    Similar time asymetricality occurs in human impacts, if you move a rain band (such as the preciptation due to the Hadley cells) you can lose good farming land in a decade, but a precipitation increase in a formerly arid region will take much more than a decade to become good fertile farmland.
    Furthermore John claims “The Anthropogenic Global Warming theory is a dying theory.” This is not the case in the scientific literature, which is where the meaningful consensus is to be found. All that said, I’m bored of so-called sceptics, so will merely suggest to John that we leave the ongoing physical process to answer his doubts.
    I did format – apologies if lost (not formatted in preview anyway).