Science The Cool Down Scientists stunned after newly surfaced data counters popular consensus on global phenomenon: ‘It changes our perception’

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Researchers have introduced a new temperature dataset that incorporates nearly seven more decades of climate data. Scientists said this more complete picture of our world’s climate could reshape how we understand the total human impact on our planet’s climate system.

“It changes our perception of how far we have already pushed the climate system in important ways,” Peter Thorne, a Maynooth University professor and ICARUS Climate Research Centre director, told CNN.

The groundbreaking temperature dataset was recently released by a team of scientists based in the United Kingdom. It incorporates climate data dating back to 1781, further into the past than most conventional datasets. Scientists usually measure modern climate change using datasets that begin in 1850, the benchmark behind estimates of nearly 1.5 degrees Celsius (2.7 degrees Fahrenheit) of warming.

The new dataset, referred to as GloSAT, indicates that heat-trapping gases rose by 2.5% between 1750 and 1850, possibly responsible for more warming than previously thought. GloSAT suggests humans are responsible for 0.09 degrees Celsius of warming over the 100-year period.

A second study published last month in the Institute of Physics journal Environmental Research Letters estimates that an additional 0.1 to 0.2 degrees Celsius of warming was caused by early increases in carbon dioxide.

“Climate simulations of the industrial era typically start in 1850, using the first 50 years as a baseline for ‘preindustrial’ climate,” according to the authors of the study. “However, the period immediately prior to 1850 is of particular interest due to early human influence and heightened volcanic activity, the latter of which led to cooler global temperatures than those observed in the subsequent historical period.”

“As the authors themselves make clear, there is larger uncertainty prior to 1850,” commented Thorne. “But it is cooler; it’s undoubtedly cooler.” The climate scientist cautions that we need to carefully consider the implications of these findings.

GloSAT indicates the planet was far cooler from the late 1700s through 1849 than during the 1850-1900 preindustrial baseline, in part due to cooling from two major early-1800s volcanic eruptions.

While the data shows more warming than once thought, scientists said it doesn’t alter climate targets or hasten expected impacts.

“It does mean we warmed the Earth more, but it doesn’t mean the impacts are suddenly going to occur sooner,” Thorne added, per CNN. “They are where they are. And they’ve almost invariably been calculated relative to a much more recent reference period.”

In Thorne’s view, the research fits into a broader picture that points to rising concern over worsening impacts. “It changes our perception of how far we have already pushed the climate system in important ways,” he explained.

The National Oceanic and Atmospheric Administration’s global climate report uses the conventional 176-year record that begins in 1850. The agency’s global climate report for November revealed that with an average temperature of 1.18 degrees Celsius (2.12 Fahrenheit) above average for the first 11 months of this year, there is a 99.9% chance that 2025 will rank among the five warmest years on record.

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