Spencer R. Hall, Alan J. Tessier, Meghan A. Duffy, Marianne Huebner, and Carla E. Cceres. Warmer Does Not Have to Mean Sicker: Temperature and Predators can Jointly Drive Timing of Epidemics. Ecology, 87(7), 2006, pp. 1684-1695
Ecologists and epidemiologists worry that global warming will increase disease prevalence. These fears arise because several direct and indirect mechanisms link warming to disease, and because parasite outbreaks are increasing in many taxa. However, this outcome is not a foregone conclusion, as physiological and community-interaction-based mechanisms may inhibit epidemics at warmer temperatures. Here, we explore this thermal-community ecology-based mechanism, centering on fish predators that selectively prey upon Daphnia infected with a fungal parasite. We used an interplay between a simple model built around this system’s biology and laboratory experiments designed to parameterize the model. Through this data-model interaction, we found that a given density of predators can inhibit epidemics as temperatures rise when thermal physiology of the predator scales more steeply than that of the host. This case is met in our nsh-Daphnia-iungus system. Furthermore, the combination of steeply scaling parasite physiology and predation-induced mortality can inhibit epidemics at lower temperatures. This effect may terminate fungal epidemics of Daphnia as lakes cool in autumn. Thus, predation and physiology could constrain epidemics to intermediate temperatures (a pattern that we see in our system). More generally, these results accentuate the possibility that warmer temperatures might actually enhance predator control of parasites.
Shuai-Lei Yao, Jing-Jia Luo, Gang Huang & Pengfei Wang. Distinct global warming rates tied to multiple ocean surface temperature changes. Nature Climate Change (2017) doi:10.1038/nclimate3304
The globally averaged surface temperature has shown distinct multi-decadal fluctuations since 1900, characterized by two weak slowdowns in the mid-twentieth century and early twenty-first century and two strong accelerations in the early and late twentieth century. While the recent global warming (GW) hiatus has been particularly ascribed to the eastern Pacific cooling, causes of the cooling in the mid-twentieth century and distinct intensity differences between the slowdowns and accelerations remain unclear. Here, our model experiments with multiple ocean sea surface temperature (SST) forcing reveal that, although the Pacific SSTs play essential roles in the GW rates, SST changes in other basins also exert vital influences. The mid-twentieth-century cooling results from the SST cooling in the tropical Pacific and Atlantic, which is partly offset by the Southern Ocean warming. During the recent hiatus, the tropical Pacific-induced strong cooling is largely compensated by warming effects of other oceans. In contrast, during the acceleration periods, ubiquitous SST warming across all the oceans acts jointly to exaggerate the GW. Multi-model simulations with separated radiative forcing suggest diverse causes of the SST changes in multiple oceans during the GW acceleration and slowdown periods. Our results highlight the importance of multiple oceans on the multi-decadal GW rates.
“A global warming research study in Canada has been cancelled because of “unprecedented” thick summer ice.
Naturally, the scientist in charge has blamed it on ‘climate change.’ “ click here
“It has taken far too long, but the self-correcting mechanisms of science finally are contradicting the global warming fraud. Despite billions of dollars of grants for those who support the so-called “consensus” (itself, a lie), and the fear of retaliation, scholars interested in the truth are publishing a wave of scientific papers contradicting the orthodoxy.” click here
“We’ve been highly critical for some time of the paper in summer 2015 by Karl et al.that claimed “the pause” or hiatus went away once “properly adjusted” ocean surface temperature data was applied to the global surface temperature dataset. Virtually everyone in the climate skeptic community considers Karl et al. little more than a sleight of hand.”
“No matter, this paper published today in Nature Climate Change by Hedemann et al. not only confirms the existence of “the pause” in global temperature, but suggests a cause, saying “…the hiatus could also have been caused by internal variability in the top-of-atmosphere energy imbalance“.” click here
“In late 2015, Soon, Connolly, and Connolly (hereafter SCC15) published a comprehensive (101 pages) analysis of how the modern anthropogenic global warming (AGW) paradigm has been constructed. The paper, published in Earth Science Reviews, is entitled Re-evaluating the role of solar variability on Northern Hemisphere temperature trends since the 19th century.” click here
“It is premature to conclude that human activities–and particularly
greenhouse gas emissions that cause global warming–have already had a detectable impact on Atlantic hurricane or global tropical cyclone activity.” click here