A blanket of
northern snow and lake-effect snow from the Great Lakes and clouds
behind an Arctic cold front are seen in an image from NOAA's GOES-East
satellite taken January 7, 2015. REUTERS/NASA/NOAA GOES Project/Handout
via Reuter.
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.”
NOAA’s updated data was also criticized by climate scientists with
the libertarian Cato Institute. Scientists Richard Lindzen, Patrick
Michaels and Chip Knappenberger argue the adjustments made by NOAA were
“guaranteed to put a warming trend in recent data.”
Cato scientists also argued that NOAA’s new data is an outlier
compared to other global temperature records, which overwhelmingly show a
hiatus in warming.
It “would seem more logical to seriously question the [NOAA] result
in light of the fact that, compared to those bulk temperatures, it is an
outlier, showing a recent warming trend that is not in these other
global records,”
the three scientists wrote.
“Adjusting good data upwards to match bad data seems questionable,
and the fact that the buoy network becomes increasingly dense in the
last two decades means that this adjustment must put a warming trend in
the data,” wrote Michaels, Knappenberger and Lindzen, who is a top
climatologist from the Massachusetts Institute of Technology.
Scientists and climate experts skeptical of man-made global warming
have become increasingly critical of temperature adjustments made by
government climate agencies like NASA and NOAA. Skeptics charge that
agencies like NOAA have been tampering with past temperatures to make
the warming trend look much more severe than is shown in the raw data.
“It is important to recognize that the central issue of human-caused
climate change is not a question of whether it is warming or not, but
rather a question of how much,” they wrote. “And to this relevant
question, the answer has been, and remains, that the warming is taking
place at a much slower rate than is being projected.”
Georgia Tech climate scientist Judith Curry also chimed in, arguing
that NOAA excluded extremely accurate sea buoy data in order to erase
the hiatus in warming. Curry wrote that it “seems rather ironic, since
this is the period where there is the greatest coverage of data with the
highest quality of measurements — ARGO buoys and satellites don’t show a
warming trend.”
“Nevertheless, the NOAA team finds a substantial increase in the
ocean surface temperature anomaly trend since 1998,” she wrote. “This
short paper in Science is not adequate to explain and explore the very
large changes that have been made to the NOAA data set. The global
surface temperature datasets are clearly a moving target. So while I’m
sure this latest analysis from NOAA will be regarded as politically
useful for the Obama administration, I don’t regard it as a particularly
useful contribution to our scientific understanding of what is going
on.”[
source]
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