Scientists Warn of 'Hothouse Earth,' 200-Foot Rise in Sea Levels

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The research highlighted 10 "feedback processes" that were predicted to kick in at around 2C of global warming.

As large parts of eastern Australia battle drought and Europe is gripped by a heatwave, Professor Steffen said current efforts to combat global warming would not be enough to meet the emission-reduction targets set by governments in the Paris Agreement, which may be insufficient to prevent the unsafe scenario anyway.

Professor Steffen said countries needed to work together to "greatly accelerate the transition towards an emission-free world economy".

However, a Hothouse Earth could turn the world's natural carbon storage systems or "sinks" into powerful greenhouse gas emitters, significantly rising temperatures.

Professor Steffen said if temperatures rose to two degrees above pre-industrial levels, a level within Paris Agreement targets, it could trigger natural processes that would cause further warming of the Earth even if all human emissions ceased.

"Avoiding this scenario requires a redirection of human actions from exploitation to stewardship of the Earth system".

Global average temperatures would exceed those of any interglacial period - meaning warmer eras that come in between Ice Ages - of the past 1.2m years.

Some of the other side effects would be a permafrost thaw, loss of methane hydrates from the ocean floor, weakening land and ocean carbon sinks, increasing bacterial respiration in the oceans, Amazon rainforest dieback, boreal forest dieback, reduction of northern hemisphere snow cover, loss of Arctic summer sea ice, and reduction of Antarctic sea ice and polar ice sheets.

"Once one is pushed over, it pushes Earth toward another".

"It may be very hard or impossible to stop the whole row of dominoes from tumbling over", he said.

"Places on Earth will become uninhabitable if "Hothouse Earth" becomes the reality", adds co-author Johan Rockström, Executive Director of the Stockholm Resilience Centre and incoming co-Director of the Potsdam Institute for Climate Impact Research.

A group of researchers published a study recently that warns the Earth is at risk of pushing into a lasting and risky hothouse state. In particular, we address tipping elements in the planetary machinery that might, once a certain stress level has been passed, one by one change fundamentally, rapidly, and perhaps irreversibly.

These dominoes may push the entire Earth system into an unpredictable new mode of operation. "We could end up delivering the Paris agreement and keep to 2C of warming, but then face an ugly surprise if the system starts to slip away".

"Hothouse planet", after 32 years, our Land may become the case if the average temperature of the planet will increase by 4-5 °C in the long term. "Research must assess this risk as soon as possible".

The only way to avoid a potential Hothouse Earth would be an active approach by scientists and environmentalists, to take "deep cuts" towards reducing greenhouse gas emissions as well as removing carbon dioxide from the atmosphere using technological advancements.

The study says that the Earth would eventually stabilise at four to five degrees higher than the current average temperature. However, there are no binding targets, and the U.S. later pulled out, dealing a blow to global efforts to form a united front against climate change.