The Rate Debate Slowing
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AT: PhytoplanktonClimate change does not harm plankton, it makes them more resilient Pedro Cermeno Departamento de Ecología y Biología Animal, Universidad de Vigo July 20, 2011 Marine planktonic microbes survived climatic instabilities in the past http://rspb.royalsocietypublishing.org/content/279/1728/474.full The results presented here demonstrate that the probability of extinction of microbial plankton species did not increase during periods of enhanced climatic instability over the past 65 Myr. Arguably, ubiquitous dispersal of marine planktonic microbes and their potential to revive after long periods of metabolic quiescence facilitated environmental tracking, habitat recolonization and community re-assembly, buffering species against extinction. Indeed, previous work has shown that communities of marine planktonic diatoms [10] and calcareous nannoplankton [34,35] recovered from climatic perturbations in the past and that their populations thrived later, once environmental conditions returned to previous-like states. However, my results also show that exceptional climatic contingencies such as those occurring across the Late Palaeocene–Eocene and the Eocene–Oligocene boundary transitions caused substantial morphological diversification. This signature is not manifest in the analysis of generic survivorship curves almost certainly because to a large extent these arising species were classified as new genera. It must be noted that only the evolutionary dynamics of species in pre-existing genera is considered in the survivorship analysis. AT: Natural DisastersClimate Change does not cause more natural disasters Ulf Buntgen et al Rudolf Brázdilc, d, Karl-Uwe Heussnere, Jutta Hofmannf, Raymond Konticg, Tomáš Kynclh, Christian Pfisterb, Kateřina Chromác, Willy Tegeli (Swiss Federal Research Institute) November 2011 Combined dendro-documentary evidence of Central European hydroclimatic springtime extremes over the last millennium http://www.sciencedirect.com/science/article/pii/S0277379111003246 A predicted rise in anthropogenic greenhouse gas emissions and associated effects on the Earth’s climate system likely imply more frequent and severe weather extremes with alternations in hydroclimatic parameters expected to be most critical for ecosystem functioning, agricultural yield, and human health. Evaluating the return period and amplitude of modern climatic extremes in light of pre-industrial natural changes is, however, limited by generally too short instrumental meteorological observations. Here we introduce and analyze 11,873 annually resolved and absolutely dated ring width measurement series from living and historical fir (Abies alba Mill.) trees sampled across France, Switzerland, Germany, and the Czech Republic, which continuously span the AD 962–2007 period. Even though a dominant climatic driver of European fir growth was not found, ring width extremes were evidently triggered by anomalous variations in Central European April–June precipitation. Wet conditions were associated with dynamic low-pressure cells, whereas continental-scale droughts coincided with persistent high-pressure between 35 and 55°N. Documentary evidence independently confirms many of the dendro signals over the past millennium, and further provides insight on causes and consequences of ambient weather conditions related to the reconstructed extremes. A fairly uniform distribution of hydroclimatic extremes throughout the Medieval Climate Anomaly, Little Ice Age and Recent Global Warming may question the common believe that frequency and severity of such events closely relates to climate mean stages. This joint dendro-documentary approach not only allows extreme climate conditions of the industrial era to be placed against the backdrop of natural variations, but also probably helps to constrain climate model simulations over exceptional long timescales.
Sherwood, Keith, and Craig Idso et al 2011 (Craig, PhD in geography @Arizona State, M.S. in Agronomy from U Nebraska) Calcifying Marine Invertebrates "Living in the Future" http://co2science.org/articles/V14/N18/EDIT.php Many are the doom-and-gloom prognostications for earth's calcifying marine invertebrates -- based on what Thomsen et al. (2010) describe as "short to intermediate (days to weeks) CO2 perturbation experiments" -- if the air's CO2 content continues to rise and the pH values of the world's ocean waters concomitantly decline, in a phenomenon that has come to be known by the fright-inducing moniker of ocean acidification. However, the eleven German researchers note that "as most laboratory experiments cannot account for species genetic adaptation potential, they are limited in their predictive power," and that "naturally CO2-enriched habitats have thus recently gained attention, as they could more accurately serve as analogues for future, more acidic ecosystems." Taking this latter course, Thomsen et al. studied the macrobenthic community in Kiel Fjord -- a naturally-CO2-enriched site in the Western Baltic Sea -- that is dominated by calcifying marine invertebrates, where they determined that in 34%, 23% and 9% of the 42 weeks they were there, the partial pressure (p) of CO2 in the water exceeded pre-industrial pCO2 (280 ppm) by a factor of three (>840 ppm), four (>1120 ppm) and five (>1400 ppm), respectively. And what did they find under these conditions? The team of German scientists reports that "the macrobenthic community in Kiel Fjord is dominated by calcifying invertebrates," such as the blue mussel (Mytilus edulis), the barnacle Amphibalanus improvisus and the echinoderm Asterias rubens; and they say that "juvenile mussel recruitment peaks during the summer months, when high water pCO2 values of ~1000 ppm prevail." In addition, they say their short-term laboratory research indicates that "blue mussels from Kiel Fjord can maintain control rates of somatic and shell growth at a pCO2 of 1400 ppm." At 4000 ppm pCO2, however, they say that both shell mass and extension rates were significantly reduced; but they found that "regardless of the decreased rates of shell growth at higher [1400] pCO2, all mussels increased their shell mass at least by 150% during the 8-week trial, even at Ωarg (Ωcalc) as low as 0.17 (0.28)," where Ω is the calcium carbonate saturate state of either aragonite (arg) or calcite (calc). In concluding the report of their field and laboratory work, as well as their mini-review of the pertinent scientific literature, Thomsen et al. state that it is likely that "long-term acclimation to elevated pCO2 increases the ability to calcify in Mytilus spp.," citing the studies of Michaelidis et al. (2005) and Ries et al. (2009) in addition to their own. And they say that they could find "no causal relationship between the acid-base status and metabolic depression in this species at levels of ocean acidification that can be expected in the next few hundred years (IPCC, 2007)," after discovering in the waters of Kiel Fjord (and demonstrating in the laboratory) that "communities dominated by calcifying invertebrates can thrive in CO2-enriched coastal areas." There is virtually no scientific understanding of ocean acidification, and it will probably be beneficial to organisms Sherwood, Keith, and Craig Idso et al 2012 (Craig, PhD in geography @Arizona State, M.S. in Agronomy from U Nebraska) The Unsettled Science of Ocean Warming and Acidification http://co2science.org/articles/V15/N19/EDIT.php The world's climate alarmists would have us believe that they know all they need to know about earth's climate system and its biological ramifications to justify an unbelievably expensive and radical restructuring of the way the industrialized world both obtains and utilizes energy. But is this really so? In an eye-opening "perspective" article published a couple of years ago in the 9 December 2009 issue of the Proceedings of the National Academy of Sciences of the United States of America, three researchers from the Marine Biogeochemistry Section of the Leibniz Institute of Marine Sciences in Kiel, Germany, describe their assessment of various possible responses of the global ocean's seawater carbonate system, plus its physical and biological carbon pumps, to ocean warming and associated changes in vertical mixing and overturning circulation, as well as the closely-allied phenomena of ocean acidification and carbonation. All of these phenomena, many of which are nonlinear and extremely complicated, are interlinked; and Riebesell and his colleagues thus conclude, from their objective review of the pertinent scientific literature, that the magnitude and even the sign of the global ocean's carbon cycle feedback to climate change are, in their words, "yet unknown." They note, for example, that "our understanding of biological responses to ocean change is still in its infancy." With respect to ocean acidification, in particular, they write that the impact it will have on marine life "is still uncertain," and that the phenomenon itself is but "one side of the story," the other side being what they call "ocean carbonation," which, as they describe it, "will likely be beneficial to some groups of photosynthetic organisms." Thus, they write that "our present understanding of biologically driven feedback mechanisms is still rudimentary," and that with respect to many of their magnitudes, "our understanding is too immature to even make a guess." What is more, they imply that even what we do think we know could well be wrong, because, as they elucidate, "our present knowledge of pH/CO2 sensitivities of marine organisms is based almost entirely on short-term perturbation experiments, neglecting the possibility of evolutionary adaptation." Adaptation solves Sherwood, Keith, and Craig Idso et al 2012 (Craig, PhD in geography @Arizona State, M.S. in Agronomy from U Nebraska) The Potential for Adaptive Evolution to Enable the World's Most Important Calcifying Organism to Cope with Ocean Acidification http://co2science.org/articles/V15/N28/EDIT.php In an important paper published in the May 2012 issue of Nature Geoscience, Lohbeck et al. write that "our present understanding of the sensitivity of marine life to ocean acidification is based primarily on short-term experiments," which often depict negative effects. However, they go on to say that phytoplanktonic species with short generation times "may be able to respond to environmental alterations through adaptive evolution." And with this tantalizing possibility in mind, they studied, as they describe it, "the ability of the world's single most important calcifying organism, the coccolithophore Emiliania huxleyi, to evolve in response to ocean acidification in two 500-generation selection experiments." Working with freshly isolated genotypes from Bergen, Norway, the three German researchers grew them in batch cultures over some 500 asexual generations at three different atmospheric CO2 concentrations - ambient (400 ppm), medium (1100 ppm) and high (2200 ppm) - where the medium CO2 treatment was chosen to represent the atmospheric CO2 level projected for the beginning of the next century. This they did in a multi-clone experiment designed to provide existing genetic variation that they said "would be readily available to genotypic selection," as well as in a single-clone experiment that was initiated with one "haphazardly chosen genotype," where evolutionary adaptation would obviously require new mutations. So what did they learn? Compared with populations kept at ambient CO2 partial pressure, Lohbeck et al. found that those selected at increased CO2 levels "exhibited higher growth rates, in both the single- and multi-clone experiment, when tested under ocean acidification conditions." Calcification rates, on the other hand, were somewhat lower under CO2-enriched conditions in all cultures; but the research team reports that they were "up to 50% higher in adapted [medium and high CO2] compared with non-adapted cultures." And when all was said and done, they concluded that "contemporary evolution could help to maintain the functionality of microbial processes at the base of marine food webs in the face of global change [our italics]." In other ruminations on their findings, the marine biologists indicate that what they call the swift adaptation processes they observed may "have the potential to affect food-web dynamics and biogeochemical cycles on timescales of a few years, thus surpassing predicted rates of ongoing global change including ocean acidification." And they also note, in this regard, that "a recent study reports surprisingly high coccolith mass in an E. huxleyi population off Chile in high-CO2 waters (Beaufort et al., 2011)," which observation is said by them to be indicative of "across-population variation in calcification, in line with findings of rapid microevolution identified here."
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