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Sunday, June 17, 2012

The End Is Near - Chicken Little meets high impact journal

The Mayan Calendar identified this year as the year of the apocalypse. However, my retirement planning is based upon having sufficient money to live beyond December 21, 2012. I can discount the predictions of ancient Mayan texts reinterpreted by New Age "Scholars", carrying on a traditions of many who preceded them predicting "The End is Near".

However, new players have now entered the game, supported by what is perceived as cutting edge science, similarly predicting that the end is near. What near means is an open question. Last week in the journal Nature (impact factor 36.1 - #1 for all general scientific journals), an apocalypse predicting article was published (behind the fire wall) entitled "Approaching a Stage Shift in Earth's biosphere".  http://www.nature.com.proxy.library.emory.edu/nature/journal/v486/n7401/full/nature11018.html#/affil-auth The authors were careful not to violate the a famous dictum of professional economics, that being never provide both a specific prediction or number and a date in the same prediction.
"Humans now dominate Earth, changing it in ways that threaten its ability to sustain us and other species. This realization has led to a growing interest in forecasting biological responses on all scales from local to global
However, most biological forecasting now depends on projecting recent trends into the future assuming various environmental pressures, or on using species distribution models to predict how climatic changes may alter presently observed geographic ranges. Present work recognizes that relying solely on such approaches will be insufficient to characterize fully the range of likely biological changes in the future, especially because complex interactions, feedbacks and their hard-to-predict effects are not taken into account."
Here we have it in the introduction to the article. The tools used to make predictions are insufficient to characterize "fully" the range of changes in the future. I am reminded of the Nicholas Taleb book "The Black Swan" and the chapter entitled "we just can't predict". In this chapter he explains the simple problem of predicting the speed and direction of billiard balls. After 40+ collisions one needs to account for every particle of the universe in order to predict the speed and direction of the last ball struck. We are talking about predicting events minutes into the future and a limited number of interactions of well defined objects and we need to account for every particle in the universe! Tell me again how we can reliably predict and control stage shifts involving the entire Earth?
The introduction of the Nature article goes on to state:
"Particularly important are recent demonstrations that ‘critical transitions’ caused by threshold effects are likely12."
What do they mean by likely??? Can they provide us with some modest quantitation here? Perhaps likely means a one in 10 chance or a 1 in a 100 or perhaps 1 in a 100 million. What time frame are they suggesting? Next week? Next year? Next century or millennium? Next million years? I do not need the mantle of science to make such predictions. The reference for this particular statement was also published in Nature in 2009 in an article entitled "Early-warning signals for critical transitions". (http://www.nature.com.proxy.library.emory.edu/nature/journal/v461/n7260/full/nature08227.html)
Notable in the introduction of this article is the statement:
"It is notably hard to predict such critical transitions, because the state of the system may show little change before the tipping point is reached. Also, models of complex systems are usually not accurate enough to predict reliably where critical thresholds may occur."
I wonder if they are ever accurate enough, particularly when the model they are dealing with is the entire earth. In any case,  I fail to see where the "likely" claim is supported, whatever the authors mean by likely. Such predictions can never be falsifiable and if they are can not be falsifiable, they cannot be science.

The authors go on the state:
"Critical transitions lead to state shifts, which abruptly override trends and produce unanticipated biotic effects. Although most previous work on threshold-induced state shifts has been theoretical or concerned with critical transitions in localized ecological systems over short time spans, planetary-scale critical transitions that operate over centuries or millennia have also been postulated. Here we summarize evidence that such planetary-scale critical transitions have occurred previously in the biosphere, albeit rarely, and that humans are now forcing another such transition, with the potential to transform Earth rapidly and irreversibly into a state unknown in human experience."
Within the article they identify previous phase shifts which include glacial–interglacial transition,
‘Big Five’ mass extinctions,.and the Cambrian explosion. Unless I am horribly mistaken all these events occurred independent of human activity. The authors imply that humans are now taking on God like characteristics and whatever the next transition may be and whenever it might happen, it will be due to human activity. I would call that a stretch. They go on to conclude:
Two conclusions emerge. First, to minimize biological surprises that would adversely impact humanity, it is essential to improve biological forecasting by anticipating critical transitions that can emerge on a planetary scale and understanding how such global forcings cause local changes. Second, as was also concluded in previous work, to prevent a global-scale state shift, or at least to guide it as best we can, it will be necessary to address the root causes of human-driven global change and to improve our management of biodiversity and ecosystem services.
Humans have engaged in all types of activities throughout history to predict and control future events ranging ranging from use of oracle bones by the ancient Chinese, astrology, water divining, dream interpretation, and other forms of magic. For much of the past two millennium the source of "truth" and tool for divination in the western world were holy scriptures and educated classes were in general agreement that the Bible held all of the information needed to divine the future and guide human decisions.   All of these approaches seemed to make sense at the time they were used and their deployment and were supported by the best evidence that these particular cultures had at the time. Some still believe this to be the case.

I too do not like surprises, particularly the types which adversely affect humanity. However, I am also distressed when the most prestigious scientific begins to sound like a press release from the Millerites. The Millerites were not quite as clever in that they provided specific dates and when the apocalypse failed to materialize, their followers lost interest. Our modern day Millerites are clever enough to cover themselves in the veil of science and use vague terms such as likely and avoid any specific time frame whatsoever.

I believe that we humans are pretty much just passengers on this planet and we have little or not real lasting impact on the course of the planet. Furthermore, we are simply delusional if believe humans are capable of predicting future courses of events and the effects of specific human actions on broad ecosystems. We may believe we can manage the earth but I believe that is a mistaken belief. We simply will never be able to muster that type of control and any attempts to develop such control mechanisms will likely have terrible unintended consequences.






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