Two climate experts who spoke at the first Innovation Zero Congress in London said that the Earth is in such bad shape that if things keep going the way they are, it will soon be unable to support human life.
Professors Johan Rockstrom, director of the Potsdam Institute for Climate Impact Research, and Sir David King, founder and chair of Cambridge’s Centre for Climate Repair, said that if the global temperature goes more than 1.5C above pre-industrial levels, tipping points will likely happen, destroying rainforests and marine life and making large parts of the tropics uninhabitable for humans.
Prof. Rockstrom and Prof. Sir David King, at the start of the Innovation Zero Congress in London, put the current trends in the starkest light possible.
The Intergovernmental Panel on Climate Change (IPCC) says that the Earth has already warmed by 1.2C. The World Meteorological Organisation warns that there is a two-thirds chance that scientists will record a 1.5C temperature sometime in the next five years, though some estimates say it could happen later this year.
At the first two-day meeting in London, Prof. Rockstrom told the people there, “1.5C is not a goal. I think of it as a physical limit.There is only one result that can be reached without any doubt at all: a rise of 2.5C in the global mean surface temperature is a disaster.
It’s something that people have never dealt with before, and there’s no proof that we can. It would be even hotter than the hottest day on Earth in the last 4 million years.We need to go to 2.5C because we’re in a place we don’t know. It would cause all of the big ice sheets to melt, which would raise the sea level by 10 metres.
There would be a collapse of all the big biomes on Earth, like the rainforest and many temperate forests. There would also be a sudden thawing of permafrost, a total collapse of marine life, and a change in where people can live.
Over a third of the land around the equator won’t be able to be lived on because the temperature will be above 30C, which is the point where people can’t stay healthy. Today, that kind of average warmth is only found in some parts of the Sahara Desert. In short, it’s somewhere we don’t want to go. The trouble is that we’re still going in that direction.”
He also said that nobody knows what will happen to the Earth’s natural processes after 1.5C, and that it will probably set off five tipping points that will make the Earth heat up out of control and lead to disaster. Prof. King said that three of these tipping points are in the Arctic, which is warming four to five times faster than the rest of the Earth.
The melting of the West Antarctic and Greenland ice sheets, the melting of permafrost in the far north, the mass death of coral reefs in the tropics, and the melting of sea ice in the Bering Sea are the five turning points that have been found.
Prof. Rockstrom said, “The big fear we have in science is when you cause tipping points, when the system goes from self-cooling to self-warming.”We’re the ones causing global warming right now, but it would be a nightmare if the world itself started doing it. We must do everything we can to stop that from happening.
When asked what he would change if he had a magic wand, Prof. King said he would make the Earth’s natural processes as important as human ones and teach us how to get rid of greenhouse gases on a large scale while refreezing the polar regions and the Himalayas.
He also said, “That 1.5C goal has to be met. If we don’t stay below that, the talk about raising the temperature to 2C and then lowering it by getting rid of greenhouse gases is not good enough. If we let the heat rise, too many people will die during that time.”
The IPCC says that the Earth will be between 2.5C and 2.7C hotter in 2100 than it was before the Industrial Revolution. In 2015, countries that are part of the UN made a promise in the Paris Agreement to keep the temperature rise to less than 2C and try to keep it to 1.5C. At the time, the 1.5C goal seemed like it could be reached, but now it seems impossible.
