Thread by @ClimateBen

Earth will warm between 2 and 6°C within decades.

It took the planet about 5,000 years to warm 5 degrees when global warming happened at various times in the past two million years.

Predicted rate of warming for the next century: at least 20 times faster.earthobservatory.nasa.gov/features/Globa…

I would agree that 'we are marching inexorably towards a “point of no return,” into territory that is unknown for the human race.'
climate.nasa.gov/climate_resour…

The warmest “hothouse earth” period: the Paleocene-Eocene Thermal Maximum, 55 million years ago.

Global temperatures during this event may have warmed by 5°C to 8°C within a few thousand years.

Mass extinctions resulted.
newscientist.com/article/dn1164…

"Jumping back to climates not seen for millions of years -- in the course of decades -- will likely totally disrupt the future of humanity".

"both ecological systems and human systems may fail to adapt rapidly enough, with devastating consequences."edition-m.cnn.com/2018/12/10/wor…

Previously, ecosystems have responded to a few degrees of global temperature change over thousands of years.

Today's unprecedented trajectory is forcing that change to occur over decades, with ecosystems also damaged by human pollution, urbanisation etc.eurekalert.org/pub_releases/2…

From 2004:

Species will struggle to adapt even with small increases in global mean temperatures:

'Between 1°C and 2°C increases in global mean temperatures most species, ecosystems and landscapes will be impacted and adaptive capacity will become limited'sciencedirect.com/science/articl…

Climates like those of the Pliocene as soon as 2030 (Mid-Pliocene: 1.8°C - 3.6°C).

😱 ⚠️ 'Both the emergence of geologically novel climates and the rapid reversion to Eocene-like climates may be outside the range of evolutionary adaptive capacity'⚠️ 😱

pnas.org/content/115/52…

1°C warming over the past 150 years, plus another 1- 4°C warming over the next 85 years. ⚠️😱

Warming rate set to increase to 50 times faster or more.

Destabilisation of the global climate faster than some of the most severe natural climate change events.theguardian.com/environment/cl…

“Climate change is already irreversible".

"We're all in big trouble”.

“The consequences for nature and humanity are sweeping and severe".

'The changes are accelerating.'

apnews.com/7fd1d533c53d46…

Leading scientists writing in one of the most respected academic journals believe the climate is more sensitive to greenhouse gases when it is warmer.

independent.co.uk/news/science/c…