National Oceanic and Atmospheric Administration scientists have found a solution to the 15-year “pause” in global warming: They “adjusted” the hiatus in warming out of the temperature record.
New climate data by NOAA scientists doubles the warming trend since the late 1990s by adjusting pre-hiatus temperatures downward and inflating temperatures in more recent years.
“Newly corrected and updated global surface temperature data from NOAA’s [National Centers for Environmental Information] do not support the notion of a global warming ‘hiatus,'” wrote NOAA scientists in their study presenting newly adjusted climate data.
To increase the rate in warming, NOAA scientists put more weight on certain ocean buoy arrays, adjusted ship-based temperature readings upward, and slightly raised land-based temperatures as well. Scientists said adjusted ship-based temperature data “had the largest impact on trends for the 2000-2014 time period, accounting for 0.030°C of the 0.064°C trend difference.” They added that the “buoy offset correction contributed 0.014°C… to the difference, and the additional weight given to the buoys because of their greater accuracy contributed 0.012°C.”
NOAA says for the years 1998 to 2012, the “new analysis exhibits more than twice as much warming as the old analysis at the global scale,” at 0.086 degrees Celsius per decade compared to 0.039 degrees per decade.
“This is clearly attributable to the new [Sea Surface Temperature] analysis, which itself has much higher trends,” scientists noted in their study. “In contrast, trends in the new [land surface temperature] analysis are only slightly higher.”
Global surface temperature data shows a lack of statistically significant warming over the last 15 years — a development that has baffled climate scientists. Dozens of explanations have been offered to explain the hiatus in warming, but those theories may be rendered moot by NOAA’s new study.
NOAA’s study, however, notes the overall warming trend since 1880 has not been significantly changed. What’s increased is the warming trend in recent decades.
“Our new analysis now shows the trend over the period 1950-1999, a time widely agreed as having significant anthropogenic global warming, is 0.113 [degrees Celsius per decade], which is virtually indistinguishable with the trend over the period 2000-2014” of 0.116 degrees per decade, according to the study.
The U.N.’s Intergovernmental Panel on Climate Change’s “statement of two years ago — that the global surface temperature has shown a much smaller increasing linear trend over the past 15 years than over the past 30 to 60 years’ — is no longer valid,” the study claims.
But that’s not all NOAA did to increase the warming trend in recent decades. Climate expert Bob Tisdale and meteorologist Anthony Watts noted that to “manufacture warming during the hiatus, NOAA adjusted the pre-hiatus data downward.”
“If we subtract the [old] data from the [new] data… we can see that that is exactly what NOAA did,” Tisdale and Watts wrote on the science blog Watts Up With That.
“It’s the same story all over again; the adjustments go towards cooling the past and thus increasing the slope of temperature rise,” Tisdale and Watts added. “Their intent and methods are so obvious they’re laughable.”