We describe planet Earth as being in the ‘Goldilocks Zone’ for life. What does this mean? It means that Earth’s orbit about the sun is at just the correct distance for life to exist. In particular, Earth’s surface maintains water in a liquid state. If the Earth were colder, the water would be solid, i.e. a snowball Earth. If the Earth were warmer, the water would quickly vaporize, making Earth unsuitable for life. Today, neither of these conditions exists, so life on Earth flourishes.
However, the Earth’s surface is a system that balances heat. Heat comes from the Sun and from the Earth’s core. Heat gets emitted as radiation. If these balance, then the Earth’s temperature remains constant. Obviously, if it doesn’t balance, then the Earth’s surface gets either hotter or cooler. We are now seeing an imbalance as temperatures are increasing.
The Earth’s oceans have heated by 337 zettajoules (3.37×1023 J) since 1955. The Arctic ice and mountain glaciers are melting. Indications are that human actions have caused this change; this imbalance. In corollary, we are changing the temperature of our bowl of porridge. Goldilocks will no longer be content with it. Nor will life flourish with it. Is this our future?