Re-Blogged From WUWT
Gradual falls and sharp rises in temperature for millions of years have profoundly affected living conditions on the planet and, consequently, our own evolution.
Mark Maslin is a professor of Earth system science in the department of geography at University College London.
Physics Today 73, 5, 48 (2020); https://doi.org/10.1063/PT.3.4474
Milutin Milanković, a brilliant Serbian mathematician and climatologist, postulated in 1941 that variations in Earth’s orbit could push the planet’s climate in or out of an ice age.1 Vital to that idea is the amount of insolation—incoming solar radiation—at 65° N, a bit south of the Arctic Circle. At that latitude, insolation can vary seasonally by 25%. Milanković argued that reductions in summer insolation allow some winter ice to survive. Each year for thousands of years, ice accumulates around 65° N and eventually forms sheets large enough to trigger an ice age.