The target could be rephrased more honestly as, “… keep global warming to within 0.5 degrees of where it is now.”
According to NASA, the latest annual temperature anomaly (2019) was 0.99 degrees above the 1880–1970 average.
If global temperatures keep rising at the same speed as the chart above indicates, then we’ll do another 0.5 degrees in the next 20 years.
According to some models, such as the one predicting IPCC Scenario B (the blue line in the chart below), we can postpone the rise past 2 degrees to 2059, or another 20 years beyond the “steady as she goes” scenario.
Can we even achieve that? Not a chance.
Here’s why:
- The lowest cost way of reducing energy consumption is by improving insulation in new buildings. But this isn’t being done very effectively. Every time a council or government tries to implement new design rules, builders find a way of getting around the rules to minimize cost.
- Conversion to most green energy isn’t viable for base load power. Wind energy is probably the greenest, but isn’t reliable; conversion to small scale hydro provides very little power; conversion to large scale hydro is generally seen as environmentally disastrous.
- Conversion to photovoltaic cells will increase greenhouse gas emissions. Photovoltaic cells provide a good alternative for peak load power (most power demand is during the day), however, the energy required to make PV cells is more than the cells will produce in 5–10 years. That means switching to PV power will INCREASE demand for coal-fired energy for decades before they start to replace coal fired power and natural gas.
- Nuclear power isn’t politically viable. While there’s some talk about new nuclear power stations in many parts of the world, the experiences of Chernobyl and Fukushima demonstrate that it isn’t safe. NIMBY was already a thing in the US after Long Island. In China, nuclear power capacity was on track to double in 20 years to 10% of electric power. That isn’t going to happen now in light of the depression.
- Switching from coal takes decades. In the past 15 years, while countries have paid lip service to their non-binding promises, nothing has changed (demand for oil, coal and natural gas increased). Why? Because you can’t simply remove billions of dollars of infrastructure without sending the economy into a tailspin. A coal fired power plant built last year is going to go on producing electricity for the next 30–50 years. Most governments don’t have the right to order companies to close them down and take a billion dollar loss; nor do they have a mandate to pay the companies a billion dollars of tax payer money in compensation. So any significant change to the mix will take 20–50 years.
And finally, there’s broad based consensus that at least some degree of global warming is a natural phenomenon. The main area of disagreement is on how much impact human emissions are adding to this.
