Everybody Hates Me

Everybody Hates Me

When I was a little nipper we did a family trip to Mt Cook - 1958 in an Austin A55?   I recall walking up from the Ball Hut onto the Tasman Glacier.  35 years later when we took our kids there the walk to the glacier was down, and by a lot.  Same with other glaciers that I know- Fox, Franz Joseph and even the Ashburton (yes there is- or was- an Ashburton Glacier- coming off Mt Arrowsmith at the head of the Ashburton River).  All over the world, glaciers are receding, and sure, I know that glaciers are as much about how much snow falls, as temperature, but if we were looking at the Earth from Mars, we would be in no doubt that it is warming, just by how much the white patches are shrinking. There's just no getting around reality: the world is warming.

But why is it warming?  What's causing it?

There are many natural cycles that affect the world's temperature, each with a different period; orbital wobbles, changes in the Sun, and volcanism are just a few of these.

And there are non-cyclical influences:

Like albedo- the earth's reflectivity- which is a function of ice cover, cloud cover, forest cover, desertification, and etc.

And plate tectonics- which determines whether there are landmasses at the poles to enable ice build-up and reduce sea levels.

And greenhouse gas concentrations. 

All of these affect how much radiation is absorbed and how much is re-radiated, which eventually influences temperature.

Plus thermal inertia of course: changes can take eons to manifest as temperature changes.

The nett effect of combinations of these influences on the world's temperature is not just unknown at this present time, but unknowable- it's a chaotic system in which tiny changes can have profound and unpredictable outcomes.

What is certain is that their various confluences (like waves on the ocean) have caused the earth's temperature and sea level to be higher and lower in the past- and will do so again in the future,

It is known that a significant part of the current warming is happening because of increases in greenhouse gases.  These are atmospheric gases such as methane and CO2 which allow the shorter wavelengths of solar radiation to pass through and heat up the earth but restrict re-radiation which is of longer wavelengths.  Water vapour is by far the dominant greenhouse gas, but its effects are difficult to quantify when in the formof clouds because it's dependent on droplet size and altitude. Without the greenhouse effect, the earth's temperature would be a chilly minus 20 degrees Celsius.

That present warming is largely a function of increasing greenhouse gas concentrations is known from the work of Manabe and Wetherald.  In 1967 they showed that if any increase in our planet's temperature was caused by increases in the concentration of greenhouse gases, a consequence would be cooling rather than warming of the stratosphere.  Other causes would not have this effect. That the stratosphere has cooled as the surface temperature increases is therefore strong evidence that a substantial part of warming is the result of an increasing greenhouse effect.

The biggest change since the industrial revolution is that CO2 has increased from 250ppm to 410ppm. The question therefore is whether this is from human activity or from coincidental natural processes?  Volcanoes and undersea vents emit around 10 times as much CO2/year as human activities, but carbon sinks in the oceans and forests re-absorb a similar amount.  Climate alarmists therefore hold human emissions responsible for the nett increase.  Are they right in this or are they blinded by ideology-they are of course, but are they in this specific instance?

A useful question bearing on this is 'if the industrial revolution had never happened, would CO2 levels have increased to the extent they have in the last 100 or so years'?    Given the slow rate of change in the 10,000 or so years before the modern era, the answer to this is that it probably would not have.   On balance, but with some trepidation I therefore conclude that recent human activity is likely to have been responsible for a substantial part of recent increases in CO2 levels in the atmosphere.

Which rather puts me off-side with climate deniers.

But at least I'm in with the Greta Thornburgh mob- right?

Except I'm not.

Because central to the climate warrior creed is the Garden of Eden narrative- that the world was perfect until man partook of the forbidden fruit, that is, had the sheer effrontery to develop agricultural and then industrial societies.

The world was not a perfect place back then- life for our progenitors was nasty brutish and short - and we would sooner rather than later have gone extinct because of some natural catastrophe (climate change for example), pandemic or have been wiped out by one of our many rival species if we had continued in a Rousseau-ian delusion.

But we've grabbed the nettle and had therefore better make a go of things or else we will entirely deserve the giant kick up the cosmic* bum that's waiting for us if we screw up.

   As I said, offside with everyone- but hopeful that history will see me right.

* My delusion of seeding the waiting universe with our electronic children.

                              Peter Lynn, Ashburton New Zealand October 2024