If the Sun got hotter or cooler would we notice on Earth?

Question

We all know that an average temperature rise of even 5°C would have catastrophic effects on our planet. Then wouldn’t the Sun changing temperature by 5°C have a similar effect?

In: Earth Science

Answer 1

5°C on the suns surface would be a change of roughly 0.1%. Since radiation energy rises with the 4th power of the temperature, it would rise by about 0.4%, or by about 5 W/m².

For comparison, a doubling of the CO2 consentration in the atmosphere is the equivalent of an extra 3.7 W/m².

So yes, a long-lasting rise of 5°C on the suns surface would have significant consequences.