See
You Ought to Have a Look: Science Round Up—Less Warming, Little Ice Melt, Lack of Imagination by Patrick J. Michaels of Cato.
"As Pope Francis, this week, focused on examining the moral issues of climate change (and largely ignoring the bigger moral issues that accompany fossil fuel restrictions),
he pretty much took as a given that climate change is “a scientific
reality” that requires “decisive mitigation.” Concurrently, unfolding
scientific events during the week were revealing a different story.
First and foremost, Roy Spencer, John Christy and William Braswell of
the University of Alabama-Huntsville (UAH)—developers and curators of
the original satellite-derived compilation of the temperature history of
the earth’s atmosphere—released a new and improved version of their
iconic data set. Bottom line: the temperature trend in the lower
atmosphere from the start of the data (1979) through the present came in
as 0.114°C/decade (compared with 0.14°C in the previous data version).
The new warming trend is less than half what climate models run with
increasing atmospheric carbon dioxide emissions project to have
occurred.
While the discrepancy between real world observations and climate
model projections of temperature rise in the lower atmosphere has been
recognized for a number of years, the question has remained as to
whether the “problem” lies within the climate models or the
observations. With this new data release, the trend in the UAH data now
matches very closely with the trend through an independent compilation
of the satellite-temperature observations maintained by a team of
researchers at Remote Sensing Systems (RSS). The convergence of the
observed data sets is an indication the climate models are the odd man
out.
As with most long-term, real-world observations, the data are covered
in warts. The challenge posed to Spencer et al. was how to splice
together remotely sensed data collected from a variety of instruments
carried aboard a variety of satellites in unstable orbits—and produce a
product robust enough for use in climate studies. The details as to how
they did it are explained as clearly as possible in this post
over at Spencer’s website (although still quite a technical post). The
post provides good insight as to why raw data sets need to be
“adjusted”—a lesson that should be kept in mind when considering the
surface temperature compilations as well. In most cases, using raw data
“as is” is an inherently improper thing to do, and the types of
adjustments that are applied may vary based upon the objective.
Here is a summary of the new data set and what was involved in producing it:
Version 6 of the UAH MSU/AMSU global satellite
temperature data set is by far the most extensive revision of the
procedures and computer code we have ever produced in over 25 years of
global temperature monitoring. The two most significant changes from an
end-user perspective are (1) a decrease in the global-average lower
tropospheric (LT) temperature trend from +0.140 C/decade to +0.114
C/decade (Dec. ’78 through Mar. ’15); and (2) the geographic
distribution of the LT trends, including higher spatial resolution. We
describe the major changes in processing strategy, including a new
method for monthly gridpoint averaging; a new multi-channel (rather than
multi-angle) method for computing the lower tropospheric (LT)
temperature product; and a new empirical method for diurnal drift
correction… The 0.026 C/decade reduction in the global LT trend is due
to lesser sensitivity of the new LT to land surface skin temperature
(est. 0.010 C/decade), with the remainder of the reduction (0.016
C/decade) due to the new diurnal drift adjustment, the more robust
method of LT calculation, and other changes in processing procedures.
Figure 1 shows a comparison of the data using the new procedures with
that derived from the old procedures. Notice that in the new dataset,
the temperature anomalies since about 2003 are less than those from the
previous version. This has the overall effect of reducing the trend when
computed over the entirety of the record.
Figure 1. Monthly global-average temperature anomalies for the
lower troposphere from Jan. 1979 through March 2015 for both the old and
new versions of LT. (Source: www.drroyspencer.com)
While this new version, admittedly, is not perfect, Spencer, Christy,
and Braswell see it as an improvement over the old version. Note
that this is not the official release, but rather a version the authors
have released for researchers to examine and see if they can find
anything that looks irregular that may raise questions as to the
procedures employed. Spencer et al. expect a scientific paper on the new
data version to be published sometime in 2016.
But unless something major comes up, the new satellite data are
further evidence the earth is not warming as expected. That means
that, before rushing into “moral obligations” to attempt to alter the
climate’s future course by restricting energy production, we perhaps
ought to spend more time trying to better understand what it is we
should be expecting in the first place.
One of the things we are told by the more alarmist crowd that we
should expect from our fossil fuel burning is a large and rapid sea
level rise, primarily a result of a melting of the ice sheets that rest
atop Greenland and Antarctica. All too frequently we see news stories
telling tales of how the melting in these locations is “worse than we
expected.” Some soothsayers even attack the United Nations’
Intergovernmental Panel on Climate Change (IPCC) for being too
conservative (of all things) when it comes to projecting future sea
level rise. While the IPCC projects a sea level rise of about 18–20
inches from its mid-range emissions scenario over the course of this
century, a vocal minority clamor that the rise will be upwards of 3 feet
and quite possibly (or probably) greater. All the while, the sea level
rise over the past quarter-century has been about 3 inches.
But as recent observations do little to dissuade the hardcore
believers, perhaps model results (which they are seemingly more
comfortable with) will be more convincing.
A new study available this week in the journal Geophysical Research Letters
is described by author Miren Vizcaino and colleagues as “a first step
towards fully-coupled higher resolution simulations with more advanced
physics”—basically, a detailed ice sheet model coupled with a global
climate model.
They ran this model combination
with the standard IPCC emissions scenarios to assess Greenland’s
contribution to future sea level rise. Here’s what they found:
The [Greenland ice sheet] volume change at year 2100 with
respect to year 2000 is equivalent to 27 mm (RCP 2.6), 34 mm (RCP 4.5)
and 58 mm (RCP 8.5) of global mean SLR.
Translating millimeters (mm) into inches give this answer: a projected 21st
century sea level rise of 1.1 in. (for the low emissions scenario; RCP
2.6), 1.3 in. (for the low/mid scenario; RCP 4.5), and 2.3 in (for the
IPCC’s high-end emission scenario). Some disaster.
As with any study, the authors attach some caveats:
The study presented here must be regarded as a necessary
first step towards more advanced coupling of ice sheet and climate
models at higher resolution, for instance with improved
surface-atmosphere coupling (e.g., explicit representation of snow
albedo evolution), less simplified ice sheet flow dynamics, and the
inclusion of ocean forcing to Greenland outlet glaciers.
Even if they are off by 3–4 times, Greenland ice loss doesn’t seem to
be much of a threat. Seems like it’s time to close the book on this
imagined scare scenario.
And while imagination runs wild when it comes to linking carbon
dioxide emissions to calamitous climate changes and extreme weather
events (or even war and earthquakes),
imagination runs dry when it comes to explaining non-events (except
when non-events string together to produce some sort of negative outcome
[e.g., drought]).
Case in point, a new study
looking into the record-long absence of major hurricane (category 3 or
higher) strikes on the U.S. mainland—an absence that exceeds nine years
(the last major hurricane to hit the U.S was Hurricane Wilma in
late-October 2005). The authors of the study, Timothy Hall of NASA’s
Goddard Institute for Space Studies and Kelly Hereid from ACE Tempest
Reinsurance, concluded that while a streak this long is rare, their results suggest
“there is nothing unusual underlying the current hurricane drought.
There’s no extraordinary lack of hurricane activity.”
Basically they
concluded that it’s “a case of good luck” rather than “any shift in
hurricane climate.”
That is all well and good, and almost certainly the case. Of course,
the same was true a decade ago when the United States was hit by seven
major hurricanes over the course of two hurricane seasons (2004
and 2005)—an occurrence that spawned several prominent papers and
endless discussion pointing the finger squarely at anthropogenic climate
change. And the same is true for every hurricane that hits the United
States, although this doesn’t stop someone, somewhere, from speculating
to the media that the storm’s occurrence was “consistent with”
expectations from a changing climate.
What struck us as odd about the Hall and Hereid paper is the lack of
speculation as to how the ongoing record “drought” of major hurricane
landfalls in the United States could be tied in with anthropogenic
climate change. You can rest assured—and history will confirm—that if we
had been experiencing a record run of hurricane landfalls, researchers
would be falling all over themselves to draw a connection to
human-caused global warming.
But the lack of anything bad happening? No way anyone wants to
suggest that is “consistent with” expectations. According to Hall and
Hereid:
A hurricane-climate shift protecting the US during active years, even while ravaging nearby Caribbean nations, would require creativity to formulate. We conclude instead that the admittedly unusual 9-year US Cat3+ landfall drought is a matter of luck. [emphasis added]
Right! A good string of weather is “a matter of luck” while bad weather is “consistent with” climate change.
It’s not like it’s very hard, or (despite the authors’ claim)
it requires much “creativity” to come up with ways to construe a lack of
major hurricane strikes on U.S. soil to be “consistent with”
anthropogenic climate change. In fact, there are loads of material in
the scientific literature that could be used to construct an argument
that under global warming, the United States should experience fewer hurricane landfalls. For a rundown of them, see p. 30 of our comments on the government’s National Assessment on Climate Change, or check out our piece titled, “Global Savings: Billion-Dollar Weather Events Averted by Global Warming.”
It is not for lack of material, but rather, for lack of desire, that
keeps folks from wanting to draw a potential link between human-caused
climate change and good things occurring in the world."
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