In the latest journal Nature, an article entitled "Approaching a state shift in Earth’s biosphere" argues for improved biological forecasting techniques in the face of an approaching "planetary-scale critical transition."
Or, to put it another way: it's quite plausible that we're nearing catastrophe, and we're not doing well enough to monitor and predict the coming storm, much less stop it.
Here's the article's abstract:
Localized ecological systems are known to shift abruptly and irreversibly from one state to another when they are forced across critical thresholds. Here we review evidence that the global ecosystem as a whole can react in the same way and is approaching a planetary-scale critical transition as a result of human influence.
After exploring previous global-scale shifts in the Earth's history, the article examines the current "shift" being caused by human activity. It also emphasizes that the magnitude of our current global environmental crisis far exceeds the last global scale-shift the Earth witnessed (the glacial-interglacial transition).
It also emphasizes some of the already-observable results and dire forecasts for the future:
Already observable biotic responses include vast ‘dead zones’ in the near-shore marine realm, as well as the replacement of > 40% of Earth’s formerly biodiverse land areas with landscapes that contain only a few species of crop plants, domestic animals and humans. Worldwide shifts in species ranges, phenology and abundances are concordant with ongoing climate change and habitat transformation. Novel communities
are becoming widespread as introduced, invasive and agricultural species integrate into many ecosystems...Recent and projected extinction rates of vertebrates far exceed empirically derived background rates. In addition, many plants, vertebrates and invertebrates have markedly reduced their geographic ranges and abundances to the extent that they are at risk of extinction.
Looking towards the year 2100, models forecast that pressures on biota will continue to increase...Modelling suggests that for ~30% of Earth, the speed at which plant species will have to migrate to keep pace with projected climate change is greater than their dispersal rate when Earth last shifted from a glacial to an interglacial climate, and that dispersal will be thwarted by highly fragmented landscapes Climates found at present on 10–48% of the planet are projected to disappear within a century, and climates that contemporary organisms have never experienced are likely to cover 12–39% of Earth. The mean global temperature by 2070 (or possibly a few decades earlier) will be higher than it has been since the human species evolved.
In short, the article warns that it's possible we should be "expecting the unexpected," meaning a massive global shift, and that we should not only be doing better to measure our changing world, but to halt the human activities which are changing it.
And as the article indicates, perhaps it is time to name the current age in which we're living, and which may become another marker on the Earth's historical timeline:
Humans have already changed the biosphere substantially, so much so that some argue for recognizing the time in which we live as a new geologic epoch, the Anthropocene. Comparison of the present extent of planetary change with that characterizing past global-scale state shifts, and the enormous global forcings we continue to exert, suggests that another global-scale state shift is highly plausible within decades to centuries, if it has not already been initiated.
If it has not already been initiated. The force of those words are almost more than I can bear.
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