Just stop burning fossil fuels!

 Honestly, it's quite simple. We have to stop burning fossil fuels to stop global temperatures rising.

Simple in concept, but not in execution.  We have to replace a couple of thousand coal power stations with wind, solar, and nuclear power.   And we have to transition our whole car and light truck fleet to EVs.  1.6 billion of them!   And find ways to power air travel with renewable fuels.  Electric planes aren't quite there yet.  Oh, and then there's cement and steel, where the manufacturing processes emit CO2, quite apart from the energy used.   But, essentially, if we can halve emissions, we will also halve the decade-by-decade rise in global temperatures from +-0.2 degrees to +-0.1 degrees.  Which will give us more time to reduce emissions from those harder sectors.

Together, land transport and electricity generation contribute roughly 50% of emissions, globally.  And the good news is that in these sectors, the clean energy alternatives are cheaper than fossil fuels.

For example, in Australia, BYD now sells an electric car (EV) which costs the same as a Toyota Corolla. Since EVs are 4 times as efficient as petrol cars (most of the fuel burnt in a conventional petrol engine is wasted as heat, and isn't used to drive the car forward) they are already much cheaper to run than petrol cars. Now, they're cheaper to buy as well. What's more, when the regulations are promulgated (why so slow, Federal Government?) you will be able to run your house on the electricity in your car. The BYD will have roughly 45 kWh of stored electricity in its battery. Average daily household use in Australia is 15 kWh. So you'll be able to charge your EV when power is cheap (midday, and again after 10 pm) and use it when power is expensive (4 pm to 9 pm). So for the same price as a petrol car, you'll get a giant household battery, cheaper car fuel bills, and much-reduced electricity bills.

This has been made possible by the collapse in battery costs. And that deep, and continuing, plunge has been parallelled by the fall in solar panel costs. While high latitudes will never be able to run on solar alone, in low and mid-latitudes, such as Australia, we will be able to run our grid on 100% solar electricity, combining it with 6 or 8 hours of storage. And EVs will be part of that revolution, as every household and every business gets them.

All these trends are being driven by market forces. Extremely competitive Chinese manufacturers are driving down prices. BYD spends as much on research as its total profit. CATL, the world's largest battery manufacturer, has introduced a sodium-ion battery. Sodium is a lot cheaper than lithium, and is also much safer. The same vigorous competition is driving down solar panel costs.

That's not to say we're out of the woods. There are powerful regressive forces which want to delay the transition, and useful idiots yelling loudly about how unfair it all is. Bring back steam trains!

Plus there are methane emissions from cattle and sheep, and CO2 from cement and steel. Methane is 80 times as potent a greenhouse gas, over a 10 year horizon (after which it decays into CO2) There's air transport, and sea transport, and home heating (bring on heat pumps!).

However, we must move faster.  The seas are dying, and half the tree of life is going extinct.  We should attempt to halve emissions by 2035, and halve them again by 2045.  With costs of solar and batteries plunging, that's achievable.