1/20 It has been a profound mistake to see climate change in terms of large physical effects like sea level rise, extreme heat etc. Rather than the ecological and biodiversity impacts which will be felt much earlier. https://twitter.com/GretaThunberg/status/1249595398794153985
2/20 It has given politicians, large corporations and the uninformed public the entirely false impression that we have far more time and that the climate crisis is far less urgent than it really is. It's taken our eye of the ball so to speak.
3/20 These ecosystem and biodiversity impacts, which are occurring now, and have largely been left out of modelling the risks, not because they're not real and serious, but due to the extraordinary complexity of them and the impossibility of modelling them.
4/20 All ecosystems, composed of myriad biodiversity/species are very finely attuned and adapted to climate. Even in a relatively small island like Great Britain there is a big regional difference in species and habitat distribution, due to regional climate differences.
5/20 If we go to somewhere like the English Lake District you can stand in one position and see lush vegetation in the valleys, different vegetation and habitat at mid-levels, and Arctic-Alpine vegetation on the mountain tops. This is all due to differences in climate.
6/20 Climate is the primary determinate of what type of species and what type of habitat exist at a given location. On even quite small spatial levels the climate varies and therefore what type of ecosystem exists at a particular location varies.
7/20 Therefore when the climate shifts beyond a certain point, all ecosystems will become unadapted to the geographical location where they now exist. Generally, this means ecosystems become less efficient and less able to sustain the biodiversity which relies on them.
8/20 Rainforests are not highly productive because they exist on rich soils (they don't) but because their ecosystems evolved over much longer time periods than ecosystems at high latitudes. This has led to more complex nutrient recycling i.e. they are far more efficient.
9/20 Without going into great detail, ecosystems less disrupted by past climate change are generally far more efficient and more recently created ecosystems, disrupted by climate change are less efficient. This is a good general rule.
10/20 Therefore when ecosystems get disrupted by climate change they generally become less efficient and don't support the same amount of biodiversity and biomass, relative to the fertility of their soils. This has profound implications for our civilization.
11/20 Our societies, our civilization, our population, our lives and our species are all reliant on a food supply system and other ecosystem services, which will be profoundly disrupted by climate change.
12/20 We're familiar with how invasive species can have huge impacts on ecosystems not adapted to them. Climate change will result in massive changes in species distribution, with species moving into new biogeographical areas they were previously excluded from by climate.
13/20 Many of these new species will be pests and pathogens etc. This will cause huge ecosystem disruption and disruption to food supply systems and economy. I cannot overstate what a huge problem this will be. Nor will it be possible to plan for it.
14/20 Much of this change and disruption will occur well before the big physical impacts we generally use to think about climate change like large scale sea level rise. Thinking of climate change in terms of these big effects has given us a false view of the situation.
15/20 We wrongly imagine ourselves just carrying on largely as we have been, just having to adapt to it getting a bit warmer, some flooding of low lying areas etc. But the elephant in the room we are ignoring is these massive ecological effects, which will occur much earlier.
16/20 Ecosystems and the biodiversity they are made up of are amazingly complex, far more complex than anything else we study and are used to thinking about. So they're generally ignored because it's very difficult to simplify them. Out of sight, out of mind.
17/20 Even worse is that the impacts on the natural world - ecosystems and biodiversity are not just being caused by climate change but other impacts of our growth obsessed economic model. https://www.theguardian.com/environment/2019/may/06/human-society-under-urgent-threat-loss-earth-natural-life-un-report
18/20 Overall, it's about the ecological crisis, not so much the climate crisis directly. Climate change is more of a cause, than an effect. The effect will be ecological and our very lives depend entirely on ecological processes i.e. ecosystem services.
19/20 We take the ecosystems that sustain us for granted. They're not a thing, they're systems, like our economy, which when disrupted cease to function as efficiently. We worry about the economy, but are blind to the ecosystems that sustain our economy, and our lives.
20/20 COVID-19 illustrates very simply how one small process can totally disrupt our economy and societies. The ecological crisis we are unwittingly precipitating will have much more far reaching consequences, than the impact of a single virus.
@GeorgeMonbiot @BellaLack @HollyWildChild @GretaThunberg @NaomiAKlein @ChrisGPackham @billmckibben @IPBES