Are worst-case climate scenarios less likely, as media reports of a new scientific paper suggest?

by David Spratt

Reading the media reporting of a new scientific paper released on 22 July, it was easy to get the impression that some “worse-case” climate warming possibilities are now off the agenda. “So this is good news?” a friend emailed. “No” was my answer.

It would be a grave mistake, and an illustration of how media reporting can get complex climate stories wrong, to find good news in this research. 

The research in question is “An assessment of Earth’s climate sensitivity using multiple lines of evidence”. Climate sensitivity is the amount of warming to be expected from a doubling of the amount of carbon dioxide in the atmosphere. The most recent Intergovernmental Panel on Climate Change (IPCC) report found the range was 1.5 to 4.5 degrees Celsius (°C).

As warming approaches 1.5°C, talk of a carbon budget for the Paris targets is delusional

by David Spratt

There's a lot of delusional talk about how much "carbon budget" (or new emissions) are allowable that would still keep global heating to the Paris target of 1.5 degrees Celsius (°C). The reality is that over the last year, global average warming was already close to 1.5°C, based on a true, pre-industrial baseline.

And the warming already in the system may well be enough to take the planet past 2°C, without any more emissions. The propositions pushed by governments, big business and many large climate movement NGOs that we have a "carbon budget" available for the Paris targets runs contrary to the evidence and suggests a world of politically convenient make-believe. 

Figure 1: Global warming July-to-June, illustrated here with a
1981-2010 baseline.  Image by CarbonBrief.

Here's why:

• According to CopernicusECMWF, globally, the twelve-month period from July 2019 to June 2020 was 0.65°C warmer than the 1981-2010 average (see chart above).
• Then 0.63°C should be added to these values to relate recent global temperatures to the pre-industrial level defined as a late 19th century baseline.
• So warming for the period July 2019-June 2020 is 1.28°C, compared to the late19th  century, for which instrumental temperature records are available from 1850.  This ties with the warmest year on record.
• But there was also warming from the start of the industrial revolution and the use of coal from the mid-eighteenth century, up to the end of the nineteenth century. That figure ranges up to 0.19°C, according to Importance of the pre-industrial baseline for likelihood of exceeding Paris goals. 
• And new research published last year found that gaps with missing data in the observational temperature record are responsible for an underestimation of the global warming between 1881–1910 and 1986–2015 by 0.1°C.
• Adding up all those components takes the warming over the last year, from a true pre-industrial base, very close to the lower end of the 1.5-2°C Paris goal, whilst recognising there is some uncertainty about warming in the pre-1850 period. 

Canberra unprepared for climate upheavals that will rock the nation

By David Sprat, first published at RenewEconomy

Covid-19 should teach us the value of being fully prepared for catastrophic risks, but on climate disruption risks the Australian Government is walking blindfolded off a cliff.

Unprecedented bushfires, Covid-19 and climate warming all raise the question of the preparedness of governments to deal with catastrophic risks, and what allows nations to successfully respond to big crises.

Those lauding the Australian Government for its pandemic response overlook the fact that, early on, this nation may have been on the disastrous "herd immunity" policy path. On 15 March, the Chief Medical Officer defended keeping schools open because “if they (school children) are getting infected and they’re perfectly well, whilst they might spread it, it also creates a herd immunity”. Australia appears to have changed course due to the stronger advocacy by State premiers, and the alarming early evidence from Italy and Spain about the consequences when the virus takes hold of a population.

In his recent book, Upheaval: How nations cope with crisis and change, geographer and anthropologist Jarod Diamond concludes that the key predictors of success in facing crises are “acknowledgment rather than denial of a crisis’s reality; acceptance of responsibility to take action; and honest self-appraisal”, plus the “presence or absence of a shared national identity” which can help a nation’s people recognise shared self-interest and unite in overcoming a crisis.