America's Forest Dieback
Severe drought in concert with a complex feedback loop is currently at work and it appears that America's Forests are about to experience a major dieback event. This event is just beginning to receive mainstream media coverage, but always without ever mentioning the forbidden words 'global warming' or 'climate change'...rather this is a 'naturally occuring' die off of the forests of the American west, according to the way the story is presented. A discussion follows of this die off and rapid climate change scenarios...
In the Abstract to the paper Massive Forest Dieback (pdf) ecologist Craig Allen of the U.S. Geological Survey points out that "most field studies and model-based assessments of vegetation responses to climate have focused on changes associated with natality and growth, which are inherently slow processes for woody plants?even though the most rapid changes in vegetation are caused by mortality rather than natality." A previous page on this subject, North American drought worst in 500 years includes a survey map which shows the results of a partial survey of the Rocky Mountain Ecosystem and indicates ongoing and widespread tree mortaility taking place in America's forests. Massive forest diebacks are taking place all over the American West, and it would seem that this taking place with little public awareness of the scale of the problem, since you don't hear much about the developing situation outside the affected areas. It was this developing die-off the ecosystem, and the state of America's forests that prompted the sudden interest of the Bush Administration in trees, and resulted in what was called the (Un)Healthy Forests Initiative, one of those Orwellian sounding government programs (Healthy Forests?) which represents both a response to the problem as well as an attempt to hide both the scale and the true nature of the problem (the use of the term 'Healthy Forests'). The solution proposed (increased logging) and the supposed root cause of the problem as described (bad environmentalists who prevented proper management of the forests through logging) failed to address the real root cause of the difficulties being experienced in the forests. The dieback is being caused by a severe climate shift. In the debate over global warming, there is much talk about traumatic and extremely damaging 'transient' shifts in climate on the road to a 'new equilibrium' and so the real question about the shift in climate in the American west as it relates to the global warming issue is whether or not this could be considered the new climate of the American West (a severe desert) or one of those rapid and sudden transient climate regimes that strike unexpectedly on the road to some new, and unknown climate regime. (See the page Our Changing Climate - a summary review for examples of other rapid and sudden climate changes that have taken place concurrent with this dieback in the American West ... this page includes an interesting comment received from a climatologist who seems to support the traditional equilibrium model of climate change...one must recall that rapid climate change is outside the mainstream as far as climatology goes today (see the references in the comments to scientific executive summary of 2001 where the authors state that due to the lack of research they can only warn about the possibility of these sudden dramatic shifts in climate, but they can provide no detailed analysis since there were no papers on the subject available for summarization).|
The question then becomes is this one of those harmful and sudden transient climate shifts or is this the new climate equilibrium for the American West, and no scientist in the world would have the answer to that question, but either way, the end result is extremely damaging and given how even a transient shift in the climate can then create new conditions that create a type of complex feedback loop, the transient winds up influencing the end result (the eventual equilibrium of the new climate regime, here assuming given the constant addition of further stimulus which increases the green house effect that there would even be a chance to achieve equilibrium - here we can see that if the dieback is a transient, the feedback comes in the form of destruction of the hydrological cycle, in that the term 'rain forest' is meaningful for a good reason, in that vegetation exhales water into the atmosphere in order to keep a siphoning action going which works from root to leaf, and thus the transient then influences the final equilibrium in that there is now certain to be even less rain due to the transient, if that is what is was, which destroyed the rain maker, the forests. Simple common sense would then indicate that the final result is therefore more likely to be equilibrium (assuming that this climate can ever achieve equilibrium given the increasing demand for fossil fuels) in the form of a low rainfall environment (the only rain produced then dependant on the oceans, since the forests were dead, and could no longer produce rain).
As for the 'Healthy Forest Initiative', it is unfair to blame the problem on 'environmentalists' and 'lack of logging', when actually it was environmentalists who were arguing that the forest fire suppression activities intended to benefit the logging industry (by saving 'valuable timber from fire') was creating dangerous fire conditions, and fires should be allowed to burn naturally. To ignore the industrial contribution to fire conditions and then blame enviromentalists is just partisan politics and one of those schemes that come out of the White House (was this one thought up by Karl Rove?) which attempts to obtain a political advantage and assign blame rather than objectively dealing with the real problems in America's forest policies. Furthermore the real problem is drought, and further deforestation, on top of the already serious dieback which is underway, is no way to minimize a drought. As well the suicidal policy of cutting in the last remaining stands of old growth rain forests should be halted. While even one old growth tree is worth close to a quarter of a million dollars, they do not call these 'old growth rain forests' for no good reason. These ancient trees move the most water into the atmosphere and the power of their rain making ability is evident to anyone who has experienced a really good soaking in the forest (or tired to keep their gear dry, which is almost impossible). Deforestation of this type which is taking place around the world is also an element in the feedback loop, which then contributes further to the end result of climate change (reduced precipitation, forests are part of the carbon cycle, as well as the lungs of the planet, increased susceptibility to natural disasters such as flooding and mudslides, and so forth).
The dieback in America's forests is the most severe in Southern California, and given the developing conditions, it looks to be the case that Southern California will lose all its forests. The situation is also very bad and getting worse in the Rocky Mountain ecosystem, as a holocaust of sorts is destroying millions and millions of trees, which once again becomes an element in a feedback loop, both in that these dead trees feed wild fires, and there is then also less rain due to the loss of rain making trees which then feeds back to kill even more trees.
This feedback loop then results in an exponentially increasing rate of dieback as the effects compound, as discussed in the Allen paper linked to above. Speaking of this sort of 'nonlinear' feedback loop and thresholds, which once exceeded cause rapid changes in an ecosystem, he wrote, "Drought-induced tree mortality exhibits a variety of nonlinear ecological dynamics. Tree mortality occurs when drought conditions cause threshold levels of plant water stress to be exceeded, which can result in tree death by loss of within-stem hydraulic conductivity (Allen and Breshears - in press). Also, herbivorous insect populations can rapidly build up to outbreak levels in response to increased food availability from drought-weakened host trees, such as the various bark beetle species (e.g. Dendroctonus, Ips, and Scolytus spp.) that attack forest trees (Furniss and Carolin 1977). As bark beetle populations build up they become increasingly successful in killing drought-weakened trees through mass attacks (Figure 1), with positive feedbacks for further explosive growth in beetle numbers which can result in nonlinear ecological interactions and complex spatial dynamics (cf. Logan and Powell 2001, Bjornstad et al. 2002). Bark beetles also selectively kill larger and low-vigor trees, truncating the size and age distributions of host species (Swetnam and Betancourt 1998)."
It is interesting to note here that the dieback of America's forests is now being discussed in mainstream media (for example there was story in Time magazine in August) and the theme of these stories is that 'drought happens all the time' and not once is the forbidden phrase 'global warming' or 'climate change' ever mentioned, even as a possible explanation. It is worth noting here that the debunking of 'global warming' is now obsolete. In order to debunk 'global warming' it would be required that one insist that one can increase green house gases without increasing the greenhouse effect. These Greenhouse gases are the tiniest component of the planet's atmosphere, a very small percentage of the gases in the atmosphere, and their potency in even these small concentrations is evidence for the power of the greenhouse effect. (These same gases are present in high concentrations in the atmosphere of Venus, with the result being that the surface temperature of Venus is close to 800 degrees.) Fortunately on Earth the percentage of these gases is tiny, thus making the planet livable, and when these gases are increased by between one third and one half (and projected to double in the future) one can of course expect an increased green house effect. For these reason the debunking of 'global warming' requires the debunking of 'the greenhouse effect', and this would be psuedo-science. The proper course of action then is to suggest, as the mainstream press reports as one example, that 'climate change is natural and drought happens all the time'. A common debunking argument suggests that while human beings have increased green house gases by a large amount, nevertheless we are in an 'interglacial' and therefore most of the warming taking place is natural, and the human component is quite small. This, by the way, seems to be the new archetype for debunking global warming, combined with the argument that 'climate change is natural'. This contradicts the evidence for 'equilibrium' and it would seem that the preference for gradual climate shifts and equilibrium is prevalent in climatology studies for the simple reason that for thousands of years the climate has been in a state of equilibrium with very little forcing of the climate. Studies of ice core gases have revealed that during an ice age the amount of green house gases in the atmosphere is lowered and during the interglacial period the amount increases, with a type of recurring feedback loop taking place over a time frame typically covering thousands of years for the transition. Thus nature does not do much 'forcing' of the climate, and given how small the amounts of greenhouse gases are in the atmosphere, such a tiny percentage, it does not take much change one way or the other to switch between glaciation and the interglacial period. So then to debunk the human contribution to global warming requires one to debunk the effects of rapid forcing which is what is taking place (if nature was to pump that much CO2 into the atmosphere, studies of the past indicate that a climate shift would take place, and so then how can one argue that such rapid forcing as we see taking place due to human activities would not result in climate changes. This newest version of the debunking argument does not make sense on a number of levels, and is just a form of denial as far as I can see, and thus it is not helpful but just another one of those stalling tactics that does not help the situation whatsoever).
One of the big controversies in climatology surrounds the issue of 'rapid climate change' versus the 'equilibrium model', and there is also the poorly understood question of 'transients' (sudden rapid changes in climate that take place when thresholds are exceeded, and which then in a complex pattern result in feedback loops that create unexpected outcomes, or 'surprises' in the field of climatology). According to what was written in the Climate Change 2001: Working Group II: under the section Impacts, Adaptation and Vulnerability rapid climate change is currently outside the mainstream of climatology, and the end result, as far as I can see, is the propogation of a type of 'equilibrium' model which gives the public the impression that in gradual manner, over say fifty or one hundred years, the climate will change. This leaves the public unprepared for the possibility of sudden, rapid climate change when thesholds are exceeded, as well as vulnerable to the shocks of sudden transients, and then there is the issue of those feedback loops and sudden surprises. The working group produced an 'executive summary' of a host of papers written in the field of climatology, which was intended for policy makers and interested readers who would not be likely to read through piles of scientific papers. They note that they were unable to provide anything more than vague warnings about the possibility of sudden, rapid climate changes due to what they called 'the paucity of literature' due to a lack of research on this subject (rapid climate change is currently outside the mainstream of climatology at this time, for it is was mainstream, then there would be papers to summarize). Commenting on this conservatism within climate science, they wrote, ""Because of the magnitude of their potential consequences, large-scale discontinuous responses warrant careful consideration in evaluations of climate change dangers. Working Group II points to the potential for such occurrences and their potential consequences for human and natural systems, but it is unable to provide detailed assessments of potential effects, given the paucity of information in the literature." They also state that, "Transient scenarios are just entering the climate impacts literature, which unfortunately tends to lag the climate effects literature by several years; thus, much of the impacts literature still is based on equilibrium climate change scenarios." And here we get those climate simulations that model gradual shifts in the climate that take 50 to 100 years to take place. In the American West we can see rapid changes taking place, and the establishment of feedback loops leading to 'nonlinear' rates of change, and the same pattern has emerged in ecosystems around the world, all at the same time (the late 1990s, as I attempted to point out in the summary page linked to above). Now if you point this out you are condemned for being 'alarmist' (exactly the criticism the climatologist made in his comments on the summary page I posted on rapid concurrent climate changes, linked to above).
However there is all sorts of evidence to indicate that the equilibrium model is incorrect, and given the forcing taking place (rapid increases in CO2) the possibility of transients and rapid or sudden climate changes increases. As well there is good evidence that the climate is a system with thesholds. IN such a system there would be small changes, as the system attempts to maintain equilibrium, and then suddenly changes take place once the threshold is crossed. Various feedback loops then feed into the process leading to 'strongly nonlinear responses' which are not slow and gradual, but rather these feedback loops can actually accelerate the process (as described above...another example of the same sort of process is the melting of glaciers or ice caps...melt water absorbs heat while ice reflects heat, so that as melting occurs, a feedback loop then begins which accelerates melting, and so we see that at the end of the 1990s south American glaciers began to melt at a rate 32 times faster than in the previous three decades, and the melt in the artic experienced a similar acceleration (about 20 times faster). It is ironic that the dumping of this much cold melt water into the ocean could then shut down the Atlantic conveyer belt currents, which brings tropical water to Europe, through a type of sinking action in the North Atlantic (as the water cools, it sinks, pulling more water up from the tropics), leading to one of those transients, in the form of a mini-ice age, a temporary effect of global warming leading to very bad winters in Europe.
Global warming during the Industrial Age
Above is the famous global warming graph, which shows how temperature has risen during the age of industrialization, and human forcing of the climate regime through rapid increases in greenhouse gases. The graph remains a source of controvery, and can be interpreted in a number of ways. You will notice, that if you ignore the 'background noise' (the sharp up and down spikes in the graph) the climate is revealed to be one of those 'choatic systems' where order emerges (one of the interesting aspects of what is known as chaos theory, where somehow a system, like the weather, which is chaotic, produces order, in this case the order being the climate regime within which chaotic weather exists). Here you can see that during the 1800s the graph is pretty much flatlined. Then at around 1900 the graph begins to climb. Once again the graph flatlines in the 1940s, and then around 1970 it begins once to climb. Thus we can see both an equilibrium reponse in the climate (the flat line areas of the graph) and a strongly nonlinear response in the climate (the rapid rises seen in the graph).
The reason for this response remains a source of controversy, but one theory that does fit the evidence is as follows. If the climate is a system with thresholds, and which attempts to maintain equilibrium, even under conditions of forcing, then one would expect the climate to not change much for a period of time. When a threshold was crossed one would expect one of those strongly nonlinear responses which are characteristic of systems with thresholds. A system with thesholds shows almost no response before the threshold is crossed, and then suddenly all that pentup energy is released in the form of a strongly nonlinear change.
Other explantions for the strangeness of the global warming graph have been proposed. However the data does fit the rapid climate change scenario, and if this was true that means that what we are experiencing around the world in recent years is part of the process of global climate change, and given the particularly rapid changes taking place in ecosystems around the world since the late 1990s, it would then follow that yet another threshold has been crossed, which would then relate the American forest dieback, which began at the end of the 1990s, to the accelerated melting of the glaciers and ice caps, which began in the late 1990s, as well as many other rapid changes (the rapid retreat of the Sahara as one more example, which began at the same time). All these strongly nonlinear responses would then be seen as related to one another, and the common media explanation for America's forest problem would be revealed as bogus (there are always droughts, it is said, while not even once is 'global warming' or 'climate change' mentioned).
Given the importance of the oceans to climate (with even far away oceans influencing countries that don't even have a shoreline on those oceans) it would also seem that these strongly nonlinear responses are also related to the sudden rise in temperature of the tropical Atlantic over the last four years, shown in the graph below.
Rise in temperature of the Tropical Atlantic from 2000 to 2004
However, as I said, rapid climate change has not been in the mainstream of climatology, and in history, it has often been the case that what has been mainstream science offers resistance to what is once on the margins, only to move into the mainstream later, so the fact that 'alarmist' scenarios about 'rapid changes' and 'transients' and 'feedback loops' are set aside in favor of the currently popularly understood model of smooth changes over 50 or 100 years does not make that scenario true, and might lead to both inappropriate levels of public apathy as well as some really unpleasant surprises in the future, as people find themselves caught up in surprising feedback loops or enduring nasty transients, and rapid climate changes related to rapid forcing of a system which it turned out had thresholds, which while it might not have changed on them before, when it finally got around to releasing all those pent up changes it gave them some very unpleasant surprises, and if those feedback loops compound they might also find themselves enduring the difficult task of adapting to increasingly rapid climate changes which it turns out were only being stored up, even though it might have seemed at the time that not much was happening.
And we can see practical examples of how even the small changes in climate we have seen so far can have catastrophic effects, as the retreat of the Sahara over the last few years has now created a locust plague which in its infancy is already being called worst than the worst year of the previous locust plagues. The FAO is now talking about famine, which isn't surprising, especially when you consider the social factors that combine with climate change to create disasters (bad debts, bad policies, and a rapid climate change - any one of these would be bad enough, but together they create a disaster on a very short time scale making adaption difficult, and given the lack of a response to the growing crisis we can see then that in the time of climate change humanity will no doubt just be forced to endure one horrible disaster after antoher with no help forthcoming, if this locust plague is going to be the archetype of what is to come. This is worth considering since it is a common strategy of global warming debunkers to talk about the rosy scenario of long growing seasons, and to hail what they call 'human adaptability', but when push comes to shove the entire system proves to be lethally nonadaptive, and what you wind up with is 'Social Darwinism'. (See the page Plague Locusts poised to destroy Sahelian Harvest for a discussion of how bad policy combines with climate change to create a particularly bad disaster.)
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