The Tipping Points of Climate Change — and Where We Stand | Johan Rockström | TED

We Earth system scientists and climate scientists are getting seriously nervous. The planet is changing faster than we have expected. We are, despite years of raising the alarm, now seeing that the planet is actually in a situation where we underestimated risks. Abrupt changes are occurring in a way that is way beyond the realistic expectations in science. Fifteen years back, I introduced the planetary boundary framework, the scientific framework with the nine Earth system processes that determines the stability, the resilience and the life support on planet Earth. Ten years back, the world signed the Paris Climate Agreement. Almost five years back, we entered the decisive decade where our choices will determine the future for all generations on planet Earth. Where are we on this journey, halfway into this decade? I will give you a scientific state of the planet report, the most objective assessment that science can give today. And it starts here. We've reached 1.2 degree Celsius of global mean surface temperature rise, the warmest temperature on Earth over the past 100, 000 years. We have just scratched on 1.5 degree Celsius as an annual mean in 2023. But what worries us most is this: we are starting to see an acceleration of warming over the past 50 years. 0.18 degrees Celsius per decade from 1970 to 2010. But then from 2014 onwards, it abruptly jumps up to 0.26 per decade. And if we follow this path, we will crash through two degrees Celsius within 20 years and hit three degrees Celsius by the year 2100, a disastrous outcome, caused by us humans. But it's not only carbon dioxide. Any parameter that matters for human well-being and our economies look the same. Here you have it, linear change up until the 1950s, we go into the great acceleration. And this is what we're seeing across overconsumption of fresh water, the sixth mass extinction of species, over-putrefying our freshwater systems with nitrogen and phosphorus, all of it undermining the stability of the planet. As if this was not enough, we are seeing that this is now causing impacts across the entire economy. We're seeing bigger and bigger invoices being sent by the Earth system onto societies across the entire world, in droughts, floods, heat waves, disease patterns, human-reinforced storms, scientifically attributed to human-caused climate change. Forty degrees Celsius of life-threatening heat across all continents, occurring in 2023. Fifty-two degrees Celsius hitting the over 1,000 who lost their lives at the Hajj pilgrimage in June in Mecca.