Risk of crossing climatic tipping points increases sharply with temps above 2°C

A new study published in Nature Communications investigates the risk of crossing planetary tipping points in climate scenarios that entail temporarily overshooting the Paris Agreement global warming temperature goals; that is, reaching a peak temperature above 1.5oC of global warming and subsequently stabilising at a lower target temperature. Most emissions trajectories that seek to stabilise the climate at 1.5oC or less entail overshooting, but the risk of a temporary overshoot triggering planetary tipping points is not well understood.  
 
The consequences of climate tipping can include a global sea level rise of several metres, ecosystem collapse, widespread biodiversity loss and substantial shifts in global heat and rainfall patterns. The study examines the risks of temporary overshooting for four critical components of the Earth system with planetary-scale impacts, namely: 

• the Atlantic Meridional Overturning Circulation (think Gulf Stream): estimated tipping time of 15 – 300 years 

• the Amazon Rainforest: estimated tipping time of 50 – 200 years  

• the Greenland Ice Sheet: tipping time of 1,000 – 15,000 years  

• the West Antarctic Ice Sheet: tipping time of 500 – 13,000 years. 

The study modelled 10 scenarios through to 2300, classified by peak overshoot temperatures (ranging from 1.53oC to 3.3oC) and subsequent stabilisation temperatures (ranging from 1.5oC down to pre-industrial levels). Under five of the scenarios, warming remained above 1.5oC in 2100 and tipping point risks were high. Scenarios that involved temperatures just 0.1oC above 1.5oC showed the lowest risk. Key findings are:   

• current policies and Nationally Determined Contributions are insufficient to minimise tipping risks, even if strong emission reductions after 2100 were to return temperatures to or below 1.5oC in the long term

• tipping risk increases with every 0.1oC of overshoot peak temperature

• scenarios that involved overshoot peak temperatures above 2.0oC entailed a non-linear acceleration of tipping risk. 

The study concluded that to effectively limit tipping risks, holding warming well below 2oC at all times is essential, even in case of a temporary overshoot above 1.5oC, and in the long term, warming needs to return to less than 1oC above pre-industrial levels.

SOURCE: ON GOOD AUTHORITY 9th August (Climate Change Authority)

Plans unveiled for massive $3.5 billion wind and solar powered green iron project for Queensland

‘Quinbrook Infrastructure Partners has thrown its hefty investment weight behind ambitious plans to convert Queensland magnetite ore into green iron, using the state’s vast wind and solar resources and and one biggest renewable hydrogen projects under development in Australia.

The $3.5 billion Gladstone Green Iron project centres on a “world class” magnetite ore deposit and its ready access to what Quinbrook describes as the “exact fundamentals” to produce and export green iron, including existing port and transmission infrastructure and abundant renewables.

In partnership with Central Queensland Metals (CQM), Quinbrook says it will sponsor the evaluation and testing of CQM’s Eulogie vanadiferous titanomagnetite ore deposit, 70km west of Gladstone, to prove its quality and scale.

Nothing in budget for electrifying transport, which will be highest emitting sector by 2030

‘The Driven posts, “Nothing in budget for electrifying transport, which will be highest emitting sector by 2030”

The federal budget has allocated virtually nothing to electrifying transport, despite the Department of Climate Change, Energy the Environment and Water (DCCEEW) projections that show transport will be the highest emitting sector in Australia by 2030.

This is in stark contrast to the $6.7 billion of funding allocated to the production of hydrogen, and a further $7 billion for critical minerals in a package totalling, by some estimates, more than $22 billion.

To put the importance of rapidly decarbonising transport into context, the lifespan of new light and heavy vehicles is around 15 years, which means that vehicles sold today will still be spewing out greenhouse gases in 2039. That highlights the urgency to bring in battery electric light and heavy vehicles now and rapidly phase out of new ICE vehicle sales.

But despite this, the federal government has chosen not to spend big on electrifying transport, while at the same time handing $6.7 billion to an as-yet unproven green hydrogen industry.