You're talking about two quite different uses of the word "austerity". Assimilating the two politically, based on nothing more than semantics, as you are doing, is inappropriate, unless it's your intention to be insulting.

• "Austerity" as defined by the austerian economists means reducing government spending : generally this means lowering social security spending, degrading health and education, things like that. Things which are service-intensive, not resource-intensive. (If the Austerians were motivated by ecological concerns, it's unlikely they would choose this method!)
  
• I went back to look for the text by Jerome that you quote (without linking), and I find it hard to believe that you really think that he is advocating austerity when he says :

European Tribune - Peak oil (demand)

peak oil translates into higher prices, which eventually causes lower demand (in those countries which are price sensitive, i.e. mostly the Western world, as a large portion of the emerging economies subside fuels) - and this is accompanied by widespread pain, as people have to do with less, or with more expensive oil, and need to reduce their consumption of everything else as a consequence.

Sure, if I can't afford as much petrol, or food, as before because of price inflation, this can be called "austerity" I guess; but I find it really strange to bracket it with economic Austerianism.

_{It is rightly acknowledged that people of faith have no monopoly of virtue - Queen Elizabeth II}