1. the curve from sperm-decline meta-analysis predicts that by 2045 median sperm counts will reach zero (because of chemicals in plastics) with no evidence the trend is tapering off
2. by 2045 global warming of >2°C may subject humans to thermal infertility
We can act.🧵
1.
We can act on this:
'If you follow the curve from the 2017 sperm-decline meta-analysis, it predicts that by 2045 we will have a median sperm count of zero. It is speculative to extrapolate, but there is also ft no evidence that it is tapering off.'dumptheguardian.com/society/2021/m…
2.
'Even species thought to roam far away from these sources of pollution are suffering from chemical contamination. A female killer whale.. was found to be one of the most contaminated biological specimens ever reported. Scientists say she never calved.'theconversation.com/male-fertility…
3.
'research suggests males of some species can become infertile even at less extreme temperatures [2-2.25C?]
Whether our findings extrapolate to other species, including mammals such as humans, is not yet clear. It’s certainly possible, given evidence..'theconversation.com/fly-infertilit…
4. More on chemicals and 'Western' sperm counts:
racist, sexist, and Eurocentric ideas 'can get embedded in the categories that scientists use to analyze data'
research needs to be 'designed, executed, and communicated by people with varied perspectives'.slate.com/technology/202…
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60-75% of Earth's species risk sudden extinction in a few decades given:
* extreme population declines
* likely vulnerability of data deficient species
* pollution and habitat & wildlife destruction trends
* accelerating warming of 3/3.5°C in 2-6 decades
Most at risk?
Primates.
Percentage of species at risk of extinction (% with declining populations)
50% (61%) of birds
47% (up to 75%) of amphibians
40% (up to 70%) of plants
40% (up to 89%) of insects
37% (up to 75%) of mammals
28% (up to 63%) of reptiles
24% (up to 84%) of fishes
66% (93%) of primates
Conservative analysis reveals utterly horrific global warming of 1.75-2°C is likely set to hit within 4 to 12 years with truly catastrophic consequences for food systems.
Estimate of 1.44°C (20-year average) warming for 2015-34:
12-40% of species extinct is considered catastrophic. So many amphibian species (~50%), plant & bird species (~40-50%), insect & mammal species (~30-40%), and reptile & fish species (~25%) are currently seen as being at risk. 48% of species are in decline. How will humans cope?
1. under a pessimistic global warming scenario (~4°C increase), climate change alone might only cause the extinction of ~20–30% of extant species in the next ~50–100 years [41,42]. Taken together, these losses would be catastrophic, but very far from 75%.' sciencedirect.com/science/articl…
2. 'Current projections of future extinction seem more consistent with ~12–40% species loss, which would be catastrophic but far from the 75% criterion used to argue for a 6th mass extinction.'
Earth's species will suffer 2-2.6°C and rising even in capitalism's most ambitious decarbonization scenario. Scientists anticipate unsurvivable 3-7°C, with geologic periods like the Miocene climatic optimum (MCO) seen as good analogues for our current 21st century climate hell.🧵
1/The race is now on to improve our knowledge of the Earth system in order to understand whether.. moderate levels of pCO2 may.. cause a devastating..increase of up to 7°C in the (near?) future, and if so, take action to prevent it. agupubs.onlinelibrary.wiley.com/doi/10.1029/20…x.com/ClimateBen/sta…
2. The temperature regime reconstructed for most of the Miocene, ∼5°C–8°C above modern, is equivalent to projected future warming in about a century under unmitigated carbon emissions scenarios.. an important warm-climate analog.. agupubs.onlinelibrary.wiley.com/doi/full/10.10… x.com/ClimateBen/sta…
COLLAPSE/EXTINCTION: scientists fear global warming of 3.5°C, which wipes out 33-70% of species (IPCC AR4 2007, IPCC AR6 2022), will likely hit by the 2060s give or take a decade or two 🧵
1. IPCC scenario SSP3-7.0 shows 3.5°C by 2080 or from 2062 (not the worst-case scenario). Even a moderate emissions scenario can lead to 3.5°C this century (new research shows 2060s-80s possible).
2. A new pre-print from highly respected climate scientists implies 3.5°C by 2065-77 at current rates of warming. The authors warn this rate could increase or decrease perhaps suggesting 3.5°C by around 2055-2087 rather like IPCC high emissions scenarios. researchsquare.com/article/rs-607…
BREAKING: scientists say Earth's major systems are undergoing abrupt changes — and soon we'll all feel them 🧵
1. 'prepare for a future of abrupt change.. choices made now will determine whether we face a future of worsening impacts and irreversible change or one of managed resilience to the changes already locked in.' phys.org/news/2025-08-s…
2. Society must now brace for catastrophic impacts.