Read here. Santer et al. 2011 research supposedly determines that at least 17 years of data is required to "measure" humans' impact on the climate. Not 15 years, not 16, not 18, not 19, not 20, but most assuredly, their cherry-picked 17-year span is the new gold-standard.
"Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature."
Soooo, what does 17 years of HadCRUT global temperatures and CO2 levels look like versus the previous 'C3' 15-year data plot? Good question!
The linear trend from this 17-year span indicates that global temperatures will be only 0.85°C higher by January 1, 2100. The light blue fitted curve suggests that global temperatures are actually moving towards a cooling period, not a warming. The grey fitted curve for CO2 keeps to a linear path ("business as usual") it has long had.
Let's identify what human CO2 impacts (past, present and future) have had on the climate per this 17-year period:
- This 17-year gold-standard, blessed by the holier than thou team of Santer et cohorts, basically confirms that human CO2 emissions have had little, if any, impact on global temperatures.
- This 17-year span confirms that climate models based on the myopic CO2-"science" are spectacularly wrong.
- This 17-year span confirms that future global warming will at most be modest.
- This 17-year data confirms what skeptics have been saying for the last 17 years: runaway positive feedback is a fantasy and future global warming is unlikely to be catastrophic.
Since this outcome is probably not what Santer et al. expected from looking at the most recent 17-year span, maybe they ought to retract their study for a major revision. It would seem the 17-year span might need to be changed - damn that pesky empirical evidence!
Note1 to readers: Go here for 17-year charts for ocean and atmosphere temps.
Note2 to readers: The linear trend that produces 0.85°C by 2100 is not a prediction. Actual global temperatures may be higher or lower. No one knows for sure. Most importantly, as this 17-year evidence indicates, current climate models are completely clueless as to future temperatures.