A series of new studies on everything from errors in calculating sea temperatures to the earth’s ability to adapt in assimilating carbon dioxide has sent climate scientists scrambling to readjust their predictions concerning climate change.

A group of scientists hailing from European research institutes are now suggesting that models used to estimate past ocean temperatures were based on an erroneous assumption, in a new study published in Nature.

Since we have no actual measurements of historic ocean temperatures, scientists must rely on proxies to estimate them, which currently involves examining ocean fossils whose development varies according to factors such as acidity, salinity and water temperature.

The level of calcite in the exoskeletons of tiny marine organisms called foraminifera is thought to vary with the isotope concentrations in their ocean environment, helping scientists to get a sense of past marine temperatures.

By experimenting with a sample of foraminifera in artificial sea water in an effort to recreate historic circumstances, however, scientists found that their reaction to factors such as heat was not what was previously thought, and actually altered the ratio of oxygen-18 to oxygen-16 in their shells—a ratio that scientists had assumed to be stable.

“This means that the paleotemperature estimates made up to now are incorrect,” said Sylvain Bernard, a mineralogist from the French National Center for Scientific Research.

“What appeared to be perfectly preserved fossils are in fact not,” he said.

According to geochemist Anders Meibom from the Swiss Federal Institute of Technology in Lausanne, this means going back to the drawing board and examining other species of marine fossils.

In order to quantify this re-equilibration, he said, “we have to work on other types of marine organisms so that we clearly understand what took place in the sediment over geological time.”

Meanwhile, Time Magazine ran a story claiming that “The Level of Carbon Dioxide in the Atmosphere Hasn’t Been This High in 800,000 Years,” based on a report released Monday by the United Nation’s World Meteorological Organization (WMO).

Time reports that although human-driven emissions of carbon dioxide have remained constant in recent years, in 2016 the increase in CO2 concentration was 50% greater than the average yearly increase over the past decade.

The WMO admitted that the sharp rise in atmospheric CO2 had little to do with human emissions, but was rather due to droughts that curbed plants’ ability to absorb CO2, caused by the natural El Niño climate event.

Basing itself on the same WMO report, BGR went further still, announcing that atmospheric CO2 levels are now the highest not in 800,000 years, but actually in 3 million years.

BGR lamented that the WMO report meant “pretty bad news for any of us imagining that climate change can be curbed before humanity causes its own extinction,” despite the report’s findings of the natural causes behind the rise in carbon dioxide.

Speaking of unforeseen natural adaptation, another report from the Finnish Meteorological Institute has found that boreal forests are now absorbing more carbon dioxide from the atmosphere, due to melting seasonal snow cover.

Part of predicting changes in carbon dioxide levels in the atmosphere involves calculating the absorption of carbon dioxide both on land and in the oceans, a phenomenon that can change from year to year due to countless factors. In the case of high-latitude boreal forests, an important carbon sink on land, the amount of snow cover directly influences the amount of carbon they can absorb.

Northern forests aren’t the only carbon sinks showing resilience—or positive adaptation—to climate change.

A new study published in the journal Nature Communications has found that plants in carbon-rich European peat bogs, one of the world’s most important carbon-storing ecosystems, have proven able to adapt to changes in temperature, precipitation and other climate-related factors.

Variations in temperature and precipitation result in significant levels of species turnover, but these changes in vegetation allow the bog itself to remain largely unaffected, the study found.

Last fall, a group of scientists Lawrence Berkeley National Laboratory similarly discovered that the world’s plants have somehow increased their capacity to assimilate carbon, resulting in an actual decline in the percentage of human-produced CO2 remaining in the atmosphere.

The researchers found to their surprise that despite the increased human emissions of greenhouse gases, between 2002 and 2014, plants were somehow able to absorb more carbon dioxide out of the atmosphere than in previous decades.

This means that certain other assumptions by climate change activists are simply wrong.

Dave Reay, for instance, a professor of carbon management at the University of Edinburgh, said recently that “as climate change intensifies, the ability of the land and oceans to mop up our carbon emissions will weaken,” a claim that directly contradicts the findings of the Finnish researchers.

Living up to his reputation as a climate alarmist, Reay said that the recent WMO report “should set alarm bells ringing in the corridors of power,” adding that “if we wait too long humankind will become a passenger on a one-way street to dangerous climate change.”

A new report in Vox, however, underscores the impact of purely natural phenomena on the environment, noting that “climate change is nothing new.” The report goes on to chronicle that long before the Industrial Revolution, “climate change” contributed decisively to the fall of the Roman Empire, a factor somehow overlooked by Edward Gibbon.

“Slight variations in the tilt, spin, and orbit of the earth change the amount and distribution of solar energy reaching its surface; the sun itself emits variable amounts of radiation; volcanoes spew ash that hangs in the upper atmosphere and reflects heat back into space,” the report declares.

“Historians have only recently begun to take into account the gold rush of new data about the climate in the classical world,” something completely unrelated to human carbon dioxide emissions.

As of the middle of the second century, Vox states, “the climate became less reliable” than it had been during the period of the Roman Republic and the early empire.

“The all-important annual Nile flood became erratic. Droughts and severe cold spells became more common,” it reads, and thus the “Climate Optimum became much less optimal.”

Climate change might have even affected barbarian invasions, the report speculates, claiming that new “paleoclimate evidence” suggests that the nomadic Huns might have moved west as a result of a “megadrought,” which drove them in desperate search for greener pastures.

None of the uncertainties, flawed proxies or unexpected natural increase in carbon dioxide assimilation have put a damper on diehard climate activists, who will meet later this week in Bonn, Germany, for the COP23 international climate conference.

“We are running out of time,” warned Nick Nuttall from the United Nations Framework Convention on Climate Change (UNFCCC). “We need COP23 to accelerate action on climate.”

Dirk Jansen, head of environmental and nature conservation policy with NRW Friends of the Earth (BUND), also believes that COP23 is the world’s last chance to combat climate change.

“It is not just about climate justice, but about the existence of humanity — and that’s a task that certainly justifies such efforts,” Jansen said.

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