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Re: [Phys-L] climate change continues apace

Reading Thomas R. Karl et al., "Possible artifacts of data biases in the recent global surface warming hiatus," note:
/
/

/First ... [r]ecently, a new correction (13) was developed and
applied in the Extended Reconstructed Sea Surface Temperature
dataset version 4, which we use in our analysis. In essence, the
bias correction involved calculating the average difference between
collocated buoy and ship SSTs. The average difference globally was
-0.12°C, a correction which is applied to the buoy SSTs at every
grid cell in ERSST version 4./
/.../
/Second, there was a large change in ship observations (i.e., from
buckets to engine intake thermometers) that peaked immediately prior
to World War II. The previous version of ERSST assumed that no ship
corrections were necessary after this time, but recently improved
metadata (18) reveal that some ships continued to take bucket
observations even up to the present day. Therefore, one of the
improvements to ERSST version 4 is extending the ship-bias
correction to the present, based on information derived from
comparisons with night marine air temperatures. Of the 11
improvements in ERSST version 4 (13), the continuation of the ship
correction had the largest impact on trends for the 2000-2014 time
period, accounting for 0.030°C of the 0.064°C trend difference with
version 3b. /
/.../
/In addition to the three improvements just discussed, since the
IPCC report (1), new analyses (24) have revealed that incomplete
coverage over the Arctic has led to an underestimate of recent
(since 1997) warming in the Hadley Centre/Climate Research Unit data
used in the IPCC report (1). These analyses have surmised that
incomplete Arctic coverage also affects the trends from our analysis
as reported by IPCC (1). We address this issue as well.

/

Ref. [13] writes: /"//Tests show that the impacts of the revisions to ship SST bias adjustment in ERSST.v4 are dominant among all revisions and updates. The effect is to make SST 0.1°–0.2°C cooler north of 30°S but 0.1°–0.2°C warmer south of 30°S in ERSST.v4 than in ERSST.v3b before 1940/." Yet Karl et al. applied it "_*at every grid cell.*_"

In the same vein, the second correction notes that "/recently improved metadata (18) reveal that _*some ships*_ continued to take bucket observations even up to the present day/" yet the "/improvement to ERSST4/" is "/extending the ship-bias correction to the present [in_*all ships*_ data]/"

And the last paragraph effectively says "we know the Arctic is getting hotter, so let's oversample it to add some weight." How about oversampling the Antarctic too? Nah, we don't want that.

Reminds me of an old Hungarian joke.

An old skeleton was found in Budapest, suspected of being of Genghis Khan. Not knowing what to do, the Hungarians placed it in a coffin and shipped it to Moscow with a note saying "Genghis Khan?" Two month later the Hungarians got a telegram back: "The Accused confessed."

Now, I realize that the great climatologist JD already pronounced the case closed. We all understand why all those new "corrections" were needed to fit the data to the model. But in typical science, shouldn't one fit the model to the data instead?

Oh, well. Plus ça change, plus c'est la même chose.

Ze'ev

On 6/8/2015 9:57 PM, John Denker wrote:
In case you missed it:

the central estimate for the rate of warming during the first 15
years of the 21st century is at least as great as the last half of
the 20th century. These results do not support the notion of a
“slowdown” in the increase of global surface temperature.
Thomas R. Karl et al. (mostly NOAA guys)
"Possible artifacts of data biases in the recent global surface warming hiatus"
Science (June 4 2015)

==========================

Pedagogical remarks:

It is better to light a candle than to curse the damn darkness.
http://www.buffyworld.com/buffy/transcripts/082_tran.html

I have been asked on various occasions (including socially, not
just professionally) how I would teach people about climate
change. I do *not* recommend attacking the issue head-on.
Instead I suggest starting with tack-tossing
https://www.av8n.com/physics/tack-tossing.htm
or some similar ultra-simple probability exercise. The point
is, people need to have some clue what real data is /supposed/
to look like. The tack data is noisy; it takes a looong time
for the running average to settle down to any kind of asymptote.

If people toss the tacks with their own hands and plot the
data with their own hands, there is "some" chance they will
believe it.

Then -- maybe -- they can look at the climate data and
understand that it's noisy. It's OK that it's noisy. It's
supposed to be noisy. One slightly-weird point in 1998 is
NOT a problem. I've been saying for more than 10 years,
loudly and publicly, that it is not a problem and has never
been a problem. There are always going to be slightly-weird
points here and there. Forsooth, if you saw a bunch of
data that never had any outliers, you would know it was
fake.

The program to lie about the dangers of climate change is
using the same techniques -- and in some cases even the
same institutions and the very same liars -- as were used
for lying about the dangers of cigarettes and the dangers
of lead in the environment. These liars are very good at
what they do.

In the real world, people make decisions all the time based
on imperfect data. If you want a pair of slippers, you don't
shop around until you find some that fit your feet /exactly/;
instead you find some that fit well enough.

People are really good at coming up for so-called "reasons"
for doing whatever selfish evil thing they feel like doing.
It has always been so. Cain had a "reason" when he slew Abel.
But enough is enough. Those who have selfish evil reasons
for spewing CO2 into the environment will always find
"reasons" why that's OK ... but let's stop pretending
that imperfect data is one of the reasons. It's not. It
wasn't a reason a year ago, or ten years ago ... and it's
certainly not a reason now.

The IMF reckons that direct and indirect subsidies to the
carbon-emitting energy industries are on the order of 5.3
trillion dollars per year.
http://www.reuters.com/article/2015/05/18/imf-energy-idUSL1N0Y61S220150518
That seems like an ultra-conservative low-ball figure to
me, but let's not worry about that right now. Accepting
it at face value means that any attempt to recapture that
money from the industry would immediately make fossil carbon
fuels uncompetitive against renewable energy, across a wide
(but not unlimited) range of applications. We could start
by leveling the playing field and letting good ole' invisible
hand do its job.
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