A thread: why seemingly small change can matter a lot over time. Why your actions now could mean a different world in 2100. Why we just have to keep on going, keep on working, with whatever access to the levers of change we have. A lesson from a computer simulation.

Today, my colleagues @climateinteract released a significant update to our #EnROADs simulation. We are always making small changes, but this was bigger than usual, with a significant impact on the 'baseline' scenario, the 'weak action' scenario that initializes the simulation.

There were several changes but the one I want to talk about here contributed to a decrease of several tenths of a degree in the global temperature in 2100. In other words - a big deal and in an encouraging direction.

This particular change didn't come from a new understanding about the climate system. It didn't come from new insights about the structure or dynamics of the energy sector.

It came because our modeling team found that we hadn't captured something in recent history as accurately as we could have. There was, it turns out, a bigger push in the real world to accelerate renewable energy in recent years than we had captured in the simulated world.

#EnROADS begins simulating in 1990, with what happens each simulated year building on and being influenced by what happened in the prior year. Like in the real world, the past gives rise to the future.

So when we recalibrated with a small change to include that historical 'push' it changed the simulated future in a bigger way. That's because this part of the simulated world (and a feature of the real world) is driven by a reinforcing feedback loop.

The more renewable energy that is installed, the more affordable it becomes, the more new renewable energy is installed. Driven by learning and economies of scale.

It's like a snowball rolling downhill, and the snowball got a bigger push than we had accounted for. When we included it, renewables in the model better tracked renewables in recent history. Not surprising.

But that's all it took to contribute to a several tenths of a degree lower future global temperature increase at the end of the century. That's what reinforcing feedback loops do. Little pushes then become self-perpetuating in the momentum of the system itself.

More support for renewables early keeps influencing the system later, enabling more renewables year after year, decade after decade in the simulated future.

So back to the real world.....Here we are, down in the details, in our little worlds, trying everyday to give as much push as we can to snowballs, little and big.

Some (most?) don't get rolling. But some do! And they gain a power and an influence on the future that grows far beyond the small change at the start.

So keep pushing my friends and don't give up. We haven't launched enough snowballs yet. There's much more to do. But our impact builds upon itself, so look up with a long view from time to time, even as you work down there in the details of strategies and policies and investments

You can learn much more about all of this in a webinar on the new model release, led by @AndrewPJones in just a few hours. If you can't attend, register anyway and we'll send you the recording. https://register.gotowebinar.com/rt/2837485879456535565

Or check out the blog post for the nitty gritty details. https://www.climateinteractive.org/policy-exercises-and-serious-games/en-roads-updated-with-new-baseline-scenario/

And check out the new #EnROADs release for yourself. https://en-roads.climateinteractive.org/scenario.html?v=2.7.35