Bluebells-in-West-Woods-10-05-09------30
Sunset2
Ogbourne
Gordon-and-Sam
Inbox-1
Pete-Gage-Band1
Silbury-Sunset---10-06-08-----07
Town-Hall-2011-05-0308-
George-Wilding-301
Remebrance-18-2
Camilla-2012-10-19152
Landscape
TdB-Pewsey044
Inquisitive-sheep-in-West-Overton
Big-Bull
Roving-Crows1
Tina-May5
Marlborough-2013-04-18StPeters
1stXV-and-others-with-Mayor
Turin-Brakes6
Scouting-for-Girls7
Camilla-MSM
Mop-Fair---10-10-09------08
Musical-Time-Machine5
Duke-of-Kent086
Animals06
SBJ
Marlborough-under-snow-from-above---Pete-Davies
BABRURY-XC-JUMP-473
Torch-2012-05-23093-
Hares017cropped
IMG8472
D4S0472
FROSTY-MORNING-
Brooks-Williams1
D4S9273
YELLOWHAMMER-473-
Snowy-High-Street
MBORO-HOCKEY-YOUTH-473
Remebrance-18-1
IMG9097
Christmas-Lights15-11-20097
EARLY-MORNING-CANTER-473-
Civic-Service-18
Sunset
White-Horse
MYFC005
JazzFestSat572
Brazier
Remebrance-18-3
4MI-2013-11-28030
D812668
Inbox2

 

This email address is being protected from spambots. You need JavaScript enabled to view it.

The Hundred Tonne Diet

 

Don’t take my word - or anyone else’s - for anything. Y ou don’t need to.  The data is so clear that you can see - see for yourself - the reality of human-induced climate change.

The graph shown below has two curves.  The first, in blue, shows the cumulative amount of carbon dioxide that we’ve put into the atmosphere since 1880 while, in red, you can see how temperatures have risen since that same year.  

 

Temperatures fluctuate a bit, as you’d expect, but the two curves are remarkably similar.  They rise together, in lockstep, and certainly seem to be strongly linked.  However, this doesn’t necessarily mean that human carbon dioxide emissions are causing temperature change.  There are four other ways the similarity could be explained:  

Perhaps climate science has got things back to front so that, in reality, temperature rises are causing increased emissions.  I hope you can see how ridiculous that is!  It implies that the rapid improvements in standards of living (and hence emissions) since the industrial revolution were driven by warming rather than by human innovation.  

Another possibility is that emissions and temperature are both pushed by some third factor.  Personally, I can’t think of anything that could do that.  Can you?  

A third alternative is that it’s just a coincidence.  Perhaps the two curves will start to look different if we just wait a little longer.  Well, this isn’t the place for a statistics lesson, but it’s quite easy to work out that two curves will look this similar, by chance, less than 0.1 per cent of the time. 

So it could be a coincidence but it’s not very likely. Would you bet the future of your grand-children on odds of a thousand to one against?

The final possibility is fraud.  That would require conspiracy on an enormous scale as the data used in these graphs has been collected by thousands of different people over a period of 130 years.  

There would need to have been collusion, from the beginning, between collectors of economic data (mostly tax collectors) and collectors of temperature data (Victorian vicars, twentieth century sea captains and NASA).  Seems implausible to me.

So the only sensible conclusion is the scientifically conventional one - human greenhouse gas emissions are causing climate change.    

The graphs also show that 1500 billion tonnes of carbon dioxide have elevated temperatures by about a degree.  So, naively, we can only emit another 750 billion tonnes if we want to keep the temperature rise below 1.5 °C.  

This simple-minded calculation is backed up by the much more sophisticated calculations of the Intergovernmental Panel on Climate Change (IPCC) whose report last October estimated that we can emit another 770 billion tonnes.

That sounds a lot but, with seven and a half billion people on the planet, it’s only another 100 tonnes each.  

Unfortunately, a typical Brit produces about seven tonnes a year and so we’ll all use our remaining share within 15 years.  We all need to go on a carbon diet and lose a few hundred kilograms a year each year.  

Two or three hundred kilograms a year is actually not that hard and I’ll talk about how in a future column.  But, in my next one, I want to look at why we think a 1.5 °C rise is the maximum safe limit.  It’s not a big temperature difference so why all the fuss?

 

19 March 2019


 

Print Email

Remebrance-18-1
JazzFestSat572
Remebrance-18-3
CivicSelfie1
Marlborough-2013-04-18StPeters
Scouting-for-Girls7
Brooks-Williams1
Ogbourne
Marlborough-under-snow-from-above---Pete-Davies
IMG9097
Hares017cropped
Town-Hall-2011-05-0308-
Civic-Service-18
Animals06
Brazier
Remebrance-18-2
Landscape
Torch-2012-05-23093-
Camilla-MSM
White-Horse
Camilla-2012-10-19152
Inquisitive-sheep-in-West-Overton
Roving-Crows1
Duke-of-Kent086
D4S0472
IMG8472
Mop-Fair---10-10-09---08
TdB-Pewsey044
MYFC005
Tina-May5
Musical-Time-Machine5
1stXV-and-others-with-Mayor
Big-Bull
Christmas-Lights15-11-20097
Gordon-and-Sam
George-Wilding-301
Silbury-Sunset---10-06-08---07
Turin-Brakes6
Sunset2
Snowy-High-Street
D812668
Sunset
Pete-Gage-Band1
D4S9273
Bluebells-in-West-Woods-10-05-09---30
SBJ
ARKManton-2012-01-1449-
4MI-2013-11-28030