There's a lovely article in the January 2025 edition of Physics World explaining the differing effects of clouds in climate models. High clouds are cooler being higher up in the atmosphere and absorb more of the outgoing radiation from the Earth's surface, reradiating a lot of it back down in the classic greenhouse warming effect that makes our planet habitable. These high clouds - like the alto-cumulus in the picture of Skeggles Water - are thinner so they also let more sunlight through which is another warming effect.
