It's worth grasping that crops are already beginning to be really severely affected *now* at 1.2/1.3/1.4C (depending on your baseline choice), before looking at how 1.7 - 2C will be enough to wreck key crops.
Did you know that over 90% of climate scientists think global warming will be so severe by 2038 or so that we'll hit temperatures shown to be hot enough to wreck the basic crops humanity relies upon for decent survival, or do you get your information from ad-dependent newspapers?
1. all time heat record June 2020 2. 95% of old ice gone 3. ice free by 2021-2031 4. fastest warming place on Earth 5. no evidence sea ice will recover 6. vast wildfires mean carbon bursts 7. melting is destabilising the climate 8. permafrost collapse is irreversible
See this thread (with another thread at the end) for details :
Few scientists would predict ~1.8C by 2030, but as far as I can tell it's a possibility (3.6C relates to the Pliocene. The earliest we may hit 3.6C according to peer-reviewed science would be the end of the 2040s (2050s more plausible).
1. If greenhouse gas emissions don't peak and fall sharply by soon after 2025, climate change will likely be severe enough to kill many billions by 2055.
2. Governments and corporations plan on increasing fossil fuel production well beyond 2025.
Let that sink in.
'The Met Office ran 17 different models with these feedbacks. All concluded a 4°C world by 2055 was likely if emissions continue to rise. Even if we are lucky, we are still likely to hit 4°C by 2070.' newscientist.com/article/dn1786…
'a 4°C world might only support one billion people'.
'Climate change is exacerbating drought in many parts of the world—increasing its frequency, severity and duration. With 2020 expected to be one of the hottest years on record, drought monitoring is crucial.'
I was told to delete this tweet because the article says 'runaway' means that at 2C (by ~2035) warming to 3C- 5C becomes inevitable. Looking at Arctic, forest and other feedbacks this looks plausible to me (particularly 3C) but I wouldn't state it as fact.
'Thawing permafrost will release carbon to the atmosphere that will have an appreciable additional effect on climate change, adding at least one quarter of a degree Celsius by the end of the century and perhaps nearly as much as one degree.'
I think a number of climate scientists consider the disappearance of summer Arctic sea ice as relatively unlikely before 2035 - 2045, but I would suggest we could well hit 1.6C - 1.9C around 2027 - 2034.
If ice-free Arctic summers became common this could lead to a staggering and obviously catastrophic 0.5C of additional global warming. It'd also influence permafrost thawing which could lead to an equally terrible ~0.2 to ~0.9 of warming by the 2090s.
Harold Wanless, director of the University of Miami’s geological sciences department and a leading expert on sea level rise, fears that a variety of feedback loops will contribute to a dramatic increase in sea level in the coming decades.
“My work on ancient climate shows we have these rapid pulses of rise that are rather dramatic, up to 10 meters of sea level rise certainly within a century, and that’s a really rapid disintegration of ice,” Wanless said. news.yahoo.com/amphtml/its-al…
“We’re just seeing the beginning of ice melt and the beginning of the warming of the waters reaching up to the Arctic, in what is most certainly going to be the beginning of one of these rapid pulses.”
'Thawing permafrost will release carbon to the atmosphere that will have an appreciable additional effect on climate change, adding at least one quarter of a degree Celsius by the end of the century and perhaps as much as one degree.' ⚠️
'When the Arctic Ocean is covered by lighter, white ice, it reflects more sunlight back to space. But when there is less ice, more heat gets absorbed by the darker ocean — warming the planet further. That warmer ocean then inhibits the growth of future ice...'
1. “Temperature increases beyond 1C may elicit rapid, unpredictable and non-linear responses that could lead to extensive ecosystem damage.”
2. '2C would be enough to threaten life as we know it.'
3. We're set to go over 2C of global warming by the 2040s
The quotes come from this 2017 article.
“The consequences of failing to keep the temperature below 1.5C will be to wilfully condemn hundreds of millions of the poorest citizens of Earth to certain deaths from the severe impacts of climate change.”
'If greenhouse gas emissions continue to increase at current rates, this warming will lead to the widespread thawing of permafrost and the release of hundreds of billions of tonnes of CO2 and billions of tonnes of CH4'
1. world's second largest reef 2. stretches 1,000 km from northern tip of Mexico’s Yucatan Peninsula toward the Bay Islands in northern Honduras 3. critically endangered; high risk from mass bleaching 4. collapse at 1.5- 2°C global warming (2020s--2030s)
'The condition of the world’s second-largest coral system, the Mesoamerican Reef stretching from Mexico to Central America, has taken a turn for the worse and faces further threats from climate change, according to a report by a group of scientists.'
'The ecosystem is at high risk from mass bleaching in the coming decades, with compounding effects of ocean acidification, hurricanes, pollution and fishing. The overall status of the ecosystem is Critically Endangered'