from The Conversation on Sep. 4, 2021.
”99.999% certainty humans are driving global warming: new study”
“There is less than 1 chance in 100,000 that global average temperature over the past 60 years would have been as high without human-caused greenhouse gas emissions, our new research shows.
”Published in the journal Climate Risk Management today, our research is the first to quantify the probability of historical changes in global temperatures and examines the links to greenhouse gas emissions using rigorous statistical techniques.
”Our new CSIRO work provides an objective assessment linking global temperature increases to human activity, which points to a close to certain probability exceeding 99.999%.
”Our work extends existing approaches undertaken internationally to detect climate change and attribute it to human or natural causes.
“The 2013 Intergovernmental Panel on Climate Change Fifth Assessment Report provided an expert consensus that:It is extremely likely [defined as 95-100% certainty] that more than half of the observed increase in global average surface temperature from 1951 to 2010 was caused by the anthropogenic [human-caused] increase in greenhouse gas concentrations and other anthropogenic forcings together.
”Decades of extraordinary temperatures
”July 2014 was the 353rd consecutive month in which global land and ocean average surface temperature exceeded the 20th-century monthly average. The last time the global average surface temperature fell below that 20th-century monthly average was in February 1985, as reported by the US-based National Climate Data Center.
”This means that anyone born after February 1985 has not lived a single month where the global temperature was below the long-term average for that month.
”We developed a statistical model that related global temperature to various well-known drivers of temperature variation, including El Niño, solar radiation, volcanic aerosols and greenhouse gas concentrations. We tested it to make sure it worked on the historical record and then re-ran it with and without the human influence of greenhouse gas emissions.Our analysis showed that the probability of getting the same run of warmer-than-average months without the human influence was less than 1 chance in 100,000
