Tuesday, August 07, 2018

Climate Change - More Bad News

An international team of climate researchers, writing in the journal, Proceedings of the National Academy of Sciences, says we could soon cross a threshold leading to boiling hot temperatures and towering seas in the centuries to come. Even if countries succeed in meeting their CO2 targets, we could still lurch on to this "irreversible pathway". Their study shows it could happen if global temperatures rise by 2C.

Each year the Earth's forests, oceans and land soak up about 4.5 billion tonnes of carbon that would otherwise end up in our atmosphere adding to temperatures. But as the world experiences warming, these carbon sinks could become sources of carbon and make the problems of climate change significantly worse. So whether it is the permafrost in northern latitudes that now holds millions of tonnes of warming gases, or the Amazon rainforest, the fear is that the closer we get to 2 degrees of warming above pre-industrial levels, the greater the chances that these natural allies will spew out more carbon than they currently now take in.

"What we are saying is that when we reach 2 degrees of warming, we may be at a point where we hand over the control mechanism to Planet Earth herself," co-author Prof Johan Rockström, from the Stockholm Resilience Centre, told BBC News. "We are the ones in control right now, but once we go past 2 degrees, we see that the Earth system tips over from being a friend to a foe. We totally hand over our fate to an Earth system that starts rolling out of equilibrium."

 According to the research paper, crossing into a Hothouse Earth period would see a higher global temperature than at any time in the past 1.2 million years. The climate might stabilise with 4-5 degrees C of warming above the pre-industrial age. Thanks to the melting of ice sheets, the seas could be 10-60 metres higher than now. Essentially, this would mean that some parts of the Earth would become uninhabitable. The impacts would be "massive, sometimes abrupt and undoubtedly disruptive," say the authors. We wouldn't really be able to do anything about it, once it starts. 

People have been thinking that climate change would be a global emergency for everyone if temperatures rose 3-4 degrees by the end of this century. But this paper argues that beyond 2 degrees, there is a significant risk of turning natural systems - that presently help keep temperatures down - into massive sources of carbon that would put us on an "irreversible pathway" to a world that is 4-5 degrees warmer than before the industrial revolution. 

We can avoid the hothouse scenario but it's going to take a fundamental re-adjustment of our relationship with the planet.

"Climate and other global changes show us that we humans are impacting the Earth system at the global level. This means that we as a global community can also manage our relationship with the system to influence future planetary conditions." 

The authors say a total re-orientation of human values, equity, behaviour and technologies is required. We must all become stewards of the Earth.

"Given the evidence of human history, this would seem a naive hope," said Prof Chris Rapley, from University College London. "At a time of the widespread rise of right-wing populism, with its associated rejection of the messages of those perceived as 'cosmopolitan elites' and specific denial of climate change as an issue, the likelihood that the combination of factors necessary to allow humanity to navigate the planet to an acceptable 'intermediate state' must surely be close to zero."

Another reason that we need to very quickly bring about socialism because capitalism cannot solve the problem of climate change.


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