I am reposting this because this man - this unsung pioneer of climate science lives just 2 km down the road from where I live. He also speaks like a true scientist - rather than as someone who as much a PR spokesperson as scientist, telling us what we apparently need to know.
If my health was better I would be endeavouring to meet him
If my health was better I would be endeavouring to meet him
Climate pioneer Dave Lowe "we only have one atmosphere"
RNZ,
26
November, 2019
This week we learned that carbon levels in the atmosphere have reached record highs. The latest figures a new global peak of 407.8 parts per million and 2018 up from 405.5 parts per million in 2017.
The numbers are shocking, Lowe says.
“Absolutely shocking. I think the thing to note there is that 408ppm in 2018, but it was 3ppm lower than that the year before. That is actually a huge increase over a single year.”
Back
in the early 1970s, Lowe was leaning into howling southerlies at
Baring head in Wellington and capturing air samples in what was known
as a Keeling flask. He still remembers the readings.
“The
number was 321ppm, I remember reporting on that. And you imagine that
just in my working lifetime 321 up to probably the southern
hemisphere number is around 406 would be my guess.
“That's
a huge increase, it's going on for 100 parts per million in my
lifetime. And that's the whole atmosphere we've changed.”
The
percentage of the atmosphere comprised of greenhouse gases such as
CO2, methane and nitrous oxide is tiny – but the effect is huge, he
says.
“The
very low concentration gases like carbon dioxide, methane is another
one, nitrous oxide, they're down there in very, very small amounts,
literally parts per million or even parts per billion and yet they
have a huge effect on the properties of the atmosphere, both the
chemistry of the atmosphere, as well, as well as its radiative
properties.”
This
is because of their amplification effects, he says.
“It’s
quite extraordinary, it turns out to be the nature of the molecule.
If you look at oxygen and nitrogen, these just have two atoms.”
Whereas
CO2 has three atoms, he says
“And
it turns out, that in terms of solar radiation and infrared
radiation, that has a huge effect.”
CO2
is like an amplifier, he says
“When
you have a guitar, you have a tiny little signal. You have to put it
into an amplifier so that your audience can hear it. This is exactly
what CO2 does.
“It’s
kind of like an amplifier, it triggers the effect of water vapour -
water vapour is the main greenhouse gas.
“And
when you listen to sceptics, this is a classic example of
pseudoscience. They'll come up and say ‘CO2 is ridiculous, you
know, there's hardly any there - it's water vapour. There's up to 1
percent of water in the atmosphere. That's the real greenhouse gas,
not CO2.
“Well,
they're absolutely right. But the fact is CO2 is driving the water
vapour, the fact that CO2 has gone up, allows the temperature of the
atmosphere to go up and increases the amount of water vapour in the
atmosphere. So, this is the amplification that I talked about.”
NIWA's
Gordon Brailsford and Katja Riedel explain how greenhouse gases are
measured at the Baring Head monitoring station.
Lowe
has been at the forefront of atmospheric science for 50 years, and a
key moment was when he crossed paths with American scientist Charles
David Keeling.
Having
graduated with a physics degree he was offered a job at the Institute
of Nuclear Sciences in Wellington in 1969. Lowe was already
developing a strong interest in atmospheric science at this point.
“It
was run by a charismatic man - a guy called Athol Rafter who actually
did, I think, have a feeling for carbon dioxide already.
"He
was worried, he was the first person to tell me about this. So, I
went out for a job interview in late 1969 and he told me about carbon
dioxide. And I couldn't believe it, I already had a lot of
atmospheric physics, but I couldn't believe that such a small amount
of this trace gas could be causing this effect. I was really bothered
about it and I started reading. there was almost no literature around
but straightaway Dave Keeling's name came up.”
Keeling
had been measuring CO2 from a measuring station in Hawaii and had
noticed a change.
“In
1957 Dave Keeling already had some measurements of CO2, they were all
over the place, he realised that he had to go into a clean
environment, so he chose a mountaintop in Hawaii called Mauna Loa, to
make the first measurements.
“And
when he started those, he noticed that the measurements were going
down, and he checked his equipment, and he couldn't believe what he
what was going on. But then it started to come up again and at the
end of the year, they were where they were before approximately, and
then they went down - and so what he was measuring was the planet
breathing.”
But
he also detected a more sinister trend, Lowe says.
“On
top of this breathing of the atmosphere, of the CO2, he saw that it
was increasing.
That's
a huge increase, it's going on for 100 parts per million in my
lifetime. And that's the whole atmosphere we've changed Dave Lowe
“And
so, his first measurement was 313, the next year it was 314, he
never, ever saw 313 again - none of us have. CO2 was increasing in
the atmosphere and that was the first sign of it.”
Keeling
realised he needed global data to establish that this was a worldwide
phenomenon, so he approached Athol Rafter in Wellington.
“He
realised that New Zealand was a very good site because of its
geographical location, as well as really good universities and he
knew Athol Rafter and the DSIR - here were the logistics that could
help him with the site.
“And
so it took a few years, but then that equipment came to New Zealand
and shortly, literally within a month or two I was working on with
that gear.”
The
first measuring station was established as Makara, and then Baring
Head, Lowe says. The continuous measuring was done by infrared
analysers, adapted from their original use in coal mines.
“What
I set up, first of all at Makara and then at Baring Head was one of
these continuous infrared analysers. And what they do, is they split
the air into a million parts and they measure exactly how many of
those parts are carbon dioxide.”
The
samples were gathered in Keeling’s simple, yet effective flask.
“It's
simple but precise, but you had to have that howling southerly wind
that you've just talked about - really unpleasant leaning over that
fence, over the edge of a cliff into something like an 80-knot
southerly from the Antarctic trying to open up the valve.”
CO2
rising, temperatures stable
And
as the 1970s progressed the science was established, the
concentrations of CO2 were increasing in the atmosphere, yet oddly
there was no consequence, temperatures were not rising
commensurately.
“If
anything, they were going down. Between 1940 and around 1980 There
was no global temperature increase.”
In
other words, he says CO2 was demonstrably going up, but there was no
consequence.
“It
wasn't really until late in the 1970s that it was discovered what was
preventing the signal from appearing was what was called global
dimming.”
Huge
amounts huge amounts of air pollution from industry and agriculture
was suppressing the greenhouse gas signal, he says.
“At
the end of the ‘70s a lot of countries really cleaned their power
stations up, they used electrostatic precipitators, they reduced all
of that air pollution that was causing the dimming and blocking out
the signal.
“So,
what happened? Like a coiled spring, up came the signal and it hasn’t
stopped.”
The
diming effect of pollution particles which prevented solar radiation
from heating the atmosphere it was “like a kind of a sunshade,”
Lowe says.
The
sceptics
Over
a lifetime in atmospheric science Lowe has repeatedly heard
pseudo-scientific, denialist arguments. A classic being CO2 is
natural, has always been in the atmosphere, so what is the problem?
And how do we know burning fossil fuel is the source?
“It
turns out that the fingerprint, or the signature, of the isotypes in
CO2 from coal, gas and oil is very, very different from natural CO2.
“So,
it really stands out; just like a fingerprint. You can see this
changing in the atmosphere. It is a smoking gun.”
Lowe
says he is both optimistic and pessimistic about the future.
“When
you get together to solve a problem and you see the strength and the
capability of some of the engineers and scientists out there, as well
as the drive from the school children.
“You
see the Fridays For Future movement started by the Swedish school
girl, Greta Thunberg. There I feel optimism, because these young
people and those highly innovative engineers, scientists are out
there. They really want to do things and they have the solutions.”
For
the orchestrated anti-science denialists, he has only contempt.
“When
it comes to people who have deliberately misinformed, I'm extremely
angry, really angry. My son believes these people belong in jail, and
I think he's right.
“The
same people who have confused the story about global warming are
involved in things like tobacco. These people are criminals, they
need to be put away.”
And
the failure to tackle greenhouse gas accumulation in the atmosphere
when we first knew the science has made our task immeasurably more
difficult, he says.
“There
is absolutely no doubt about that. It's become harder and harder, the
longer we've waited.”
NIWA's
Gordon Brailsford and Katja Riedel explain how greenhouse gases are
measured at the Baring Head monitoring station.
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