SHARE
EARTH HOTTER THAN EVER – RISKING A HOTHOUSE POINT OF NO RETURN
According to scientists, Earth is becoming hotter than ever – much faster than we initially thought. And it will have severe health & economic consequences.
By: Sigrid Vestergaard Frandsen, Director of Environmental Health
For 11,000 years, Earth’s stable climate allowed human civilization to flourish. A new study warns that that era is over. We are entering an "unprecedented" period of warming that threatens to trigger a "hothouse trajectory" — a self-sustaining cycle of heating that human intervention may be too powerless to stop, once it begins.
​
According to the climate scientists behind the study, the world is closer than we think to a “point of no return” after which runaway global heating cannot be stopped.
​
This can trigger a cascade of climate feedback loops, ultimately making our world a "hothouse trajectory," far worse than the 2-3° C temperature rise the world is reaching. This new hothouse climate would be devastating compared to the past 11,000 years of stable climate, during which human civilisation has developed.​
What are "feedback loops"?
It’s no longer just about the greenhouse gases we pump into the air. It’s about how the Earth reacts to that heat
Melting ice
Less ice means fewer white regions on Earth, which in turn means less sunlight reflected (albedo), leading to more heat absorbed by the planet.
We're already seein this with the melting of the Greenland and Antarctic ice sheets, mountain glaciers and polar sea ice
Permafrost thaw
Increases in CO2 in the atmosphere cause permafrost to melt and release methane, which is 80 times as strong at trapping heat on Earth than CO2.
We are already seeing this in Alaska, Canada, Siberia and Lapland. Exposing the Arctic inhabitants to methane gas.
Stronger Storms
Less sea ice means the ocean will absorb more heat from the sun (90% of heat is already absorbed by ocean water). As oceans warm, they power ever stronger storms, particularly in the tropics, in the form of hurricanes and typhoons, destroying homes, villages and killing humans and wildlife.
According to Dr Christopher Wolf, a scientist at Terrestrial Ecosystems Research Associates in the US, "it’s likely that global temperatures are [already] as warm as, or warmer than, at any point in the last 125,000 years and that climate change is advancing faster than many scientists predicted.” It is also likely that carbon dioxide levels are the highest they have been in at least 2 million years.
​
Prof Tim Lenton, an expert on tipping points at the University of Exeter in the UK, said: “We don’t need to be heading towards a hothouse Earth for there to be profound risks to humanity and our societies – these will already be upon us if we continue to a 3º C world.”
Tipping points may already be observed in Greenland and western Antarctica, with the melting of permafrost and mountain glaciers. In the Amazon rainforest, deforestation may be approaching a "point of no return" for the microclimate that the forest creates.
Health and economic consequences
​
The "hothouse" point of no return that we are rapidly moving towards will have – and already has – severe health and economic consequences. In the US, heatwaves are killing thousands and causing energy failures, while wildfire smoke can turn our air unbreathable and lead to respiratory diseases. Pollution and energy bills are already skyrocketing due to cooling demands in homes and workplaces.
The melting of ice sheets and sea ice can warm our oceans significantly, deteriorating the Gulf Stream, ultimately making our winters much colder. Warm oceans will also lead to greater storms and the destruction of homes, villages and wildlife.
​
​Across the world, areas do not warm equally, making some countries hotter than others. This means, in Kenya, school children are experiencing fatigue during class. In the Sahel, warming is fueling disease outbreaks such as malaria, Zika, chikungunya, Guinea Worm, and yellow fever.