Oh, wow, oh, oh, wow, oh, wow, oh, wow.

Oh, wow.

Oh, my. Hello, you're listening to the Science of Everything podcast, episode 141, natural climate change.

I'm your host, James Fodor. So here we continue on from the previous episode, and we talk about some of the

mechanisms by which climate changes over time without human influence. So this builds on the prerequisite, episode 140,

a history of Earth's climate, whereas in that episode we gave a kind of a narrative overview of

changes in the Earth's climate over long and shorter periods of time. In this episode, we're going

to try to explain some of the reasons for those changes,

focusing on the natural forcing mechanisms. So in particular, we'll talk about the,

we'll talk about changes in the radiation emissions from the sun, we'll talk about the effect

of volcanic activity, we'll talk about the effect of the changes in Earth's orbits,

Milankovic cycles, and we'll discuss the effect of the silicate carbonate weathering

processes and the carbon cycle in changing the quantity of carbon dioxide that is in the

atmosphere over very long periods of time. So I've already said

they're prerequisite as episode 140, so please give that a listen before this one, because it

continues directly on. And without further ado, let's get started. So far, I've been describing

changes in Earth's climate, and I've mentioned some of the reasons for them. I've mentioned, for example, the

changes owing to changes in the Earth's orbit, but I haven't really given much of a detailed

explanation. So that's what we're now going to turn to, and this will also form an important

backdrop against which we can understand the greenhouse effect and the impact of human emission of

greenhouse gases. So first of all, let's start by talking about the concept of radiative forcing.

Radiative forcing is a change in the energy passed to the atmosphere, or the term is energy flux,

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