A largely unreported study published in August finds no evidence of a tipping point for the climate as the US continues to lead the world in carbon emission reductions even after pulling out of the failed Paris Climate Accords
The climate doomsday clock in Times Square flashes ominously, “Earth has a deadline,” and then proceeds to count it down to the second. As of this morning, it read “7 yrs 017 days 20:41:20.” By the time I post this article it will have ticked down another day.
Nor is this the only warning about the Earth’s expiration date. In October 2018, the United Nations warned that there was only 12 years left to save the planet. Scientific American fears that we’ll cross the threshold by 2036.
Neither are these claims a new phenomenon, emerging only over the past few years: In 2006, former Vice President Al Gore put the figure out 10 years, making us 4 years too late. In 2009, Prince Charles claimed there were only a hundred months left, putting us a year overdue already.
Right or wrong, these claims are based on a pretty simple concept: The tipping point. In his excellent book, The Tipping Point: How Little Things Can Make a Big Difference, Malcom Gladwell defines a tipping point as “the moment of critical mass, the threshold, the boiling point.” The point where what comes after is different than what came before.
In terms of climate, the tipping point is considered the point of no return for the future of the Earth and humanity itself. While models predict the world will warm somewhere around 3-5 degrees celsius above pre-industrial levels by 2100, the period during which we can have an impact on the outcome is much shorter according to the scientists and accompanying policy makers.
Therefore, if we don’t act before a certain date, the warming will continue unchecked no matter what we do. As Time magazine reported in July: “We’re standing at a climate crossroads: the world has already warmed 1.1°C since the Industrial Revolution. If we pass 2°C, we risk hitting one or more major tipping points, where the effects of climate change go from advancing gradually to changing dramatically overnight, reshaping the planet. To ensure that we don’t pass that threshold, we need to cut emissions in half by 2030.”
There’s only one problem with these pronouncements: They’re simply not true according to a study published in Nature Ecology & Evolution earlier this year. Not surprisingly, this study received absolutely no attention in the mainstream media. In fact, the doomsday clock in New York City was turned on after it was published.
Regardless, Helmut Hillebrand, Ian Donahue, and others looked at 36 meta-analyses that measured more than 4,600 global change impacts on natural communities to determine that such tipping points are rarely detectable, either within the individual analyses or across the analyses.
The study starts by defining the thresholds. “Concepts of thresholds, tipping points and regime shifts dominate current ecological frameworks aiming to understand ecosystem responses to anthropogenic global change. A threshold corresponds to a level of environmental pressure that creates a discontinuity in the ecosystem response to this pressure.”
The climate clock in New York counts down to the hypothetical threshold after which we will lose control over the increase in temperature in the future (the discontinuity). Of course, this line of thinking assumes both the existence of a threshold and that it can be predicted with some precision.
As the study notes, the thresholds “implementation in policy hinge upon the assumption that the presence of thresholds can be detected in data or—even better—predicted.” Forget predictions, however, the study had a hard time detecting the existence of thresholds entirely across the thousands of different experiments they analyzed.
To try to find these thresholds, the authors reasoned that after a threshold was crossed, you would expect to see “increased variance in response to variables,” meaning the change to the system is greater after than the threshold than before. It has crossed the tipping point.
Yet, the authors were only able to find such thresholds in less than a quarter of the studies. “Significant changes in the variance of effect sizes were present in only eight out of 36 cases, challenging the widespread expectation of rising variance as a signal of threshold transgression. Moreover, in those cases… the increase in variance occurred frequently only at the most extreme pressure level observed in the respective meta-analysis.”
The authors likened this extreme pressure event to hitting the system with a sledgehammer. “This observation resembles a ‘sledgehammer effect’; that is, system transformation by huge impact, which is a trivial consequence of the large pressure magnitude and the complete transformation of the system.”
Meaning, the system didn’t cross the tipping point via a gradual means like increasing CO2 in the atmosphere. The threshold was crossed by a single, large event.
The study went even further and attempted to use simulations to detect these thresholds, also with no luck. “The simulations corroborate our general empirical finding across the 36 datasets that thresholds are rarely detectable in data even if using statistical methods developed for threshold detection.”
Even worse for the doomsday clock proponents, “even when thresholds were detected, limited inference can be made.” “Analysis of the 4,601 experiments that we assembled here, potentially the most comprehensive data available, did not enable us to estimate where thresholds might have been crossed.”
Ultimately the study concludes that data suggests the opposite, favoring smaller, gradual shifts as a result of man-made influence. “Instead, the data suggest that the ecosystem impacts of human-induced changes in environmental drivers are better characterized by gradual shifts in response magnitudes with increasing pressure coupled with broad variations around this trend.”
Of course, the authors are clear to indicate that anything remains possible; some systems may be subject to tipping points, but not enough to base policy on them, much less claim the end of the world is nigh. “While our analyses do not rule out the existence of tipping points, they bring into question the utility of threshold-based concepts in management and policy if we cannot detect thresholds in nature.”
Translation: There is no climate doomsday clock.
This December also marks the fifth anniversary of the Paris Climate Accords, the non-binding agreement to reduce carbon emissions worldwide. The accords were adopted by 196 Parties in Paris on December 12, 2015, taking effect on November 4, 2016. The goal was to limit global warming to well below 2 degrees Celsius, compared to pre-industrial levels.
According to the United Nations, “to achieve this long-term temperature goal, countries aim to reach global peaking of greenhouse gas emissions as soon as possible to achieve a climate neutral world by mid-century.”
Though much was made of President Trump pulling the United States out of the agreement, very little attention is paid to the underlying facts. “The decision to leave the Paris agreement was wrong when it was announced and it is still wrong today,” explained Helen Mountford from the World Resources Institute. “Simply put the US should stay with the other 189 parties to the agreement, not go out alone.”
Yet, carbon emissions from the burning of fossil fuels for energy and cement production in the United States peaked in 2007 at 6.13 billion metric tons. By 2016, these emissions had already been reduced to 5.31 billion, a 13.4% drop.
The US’s share of global carbon emissions has also declined steadily, from 24.2% in 2000 to 14.58% in 2016. During this same period, China’s share of emissions has risen from 13.61% to 27.21%. India’s share of emissions has also increased from 4.19% in 2000 to 6.8% in 2016. Both countries’ emissions are rising far faster than the US is falling. For example, China’s went from 6.86 billion in 2007 to a whopping 9.84 billion in 2016.
The situation in those countries hasn’t improved after the accords, either. In fact, the United States leads the world in the reduction in global emissions over the past 2 years. Commenting on 2019 and 2020’s figures, the executive director of the International Energy Agency, Fatih Birol, said to Reuters: “Two years in a row the largest reductions in global emissions came from the US. If we like it or not these are the numbers.”
If numbers don’t lie, why are scientists and the media obsessed with thresholds that don’t exist and non-binding agreements that don’t appear to be slowing the growth in carbon emissions of the two largest polluters?
Thanks to advances in technology including the much-maligned fracking and switch to natural gas, the United States is among the few countries in the world likely to even come close to the Paris Climate Accord targets, with or without formally participating in the agreement. China and India, however, are formally participating and continue to increase their emissions.
Does that make any sense to you? Somehow, it does to the scientists and policy makers.