Currently, Earth's eccentricity (orbital shape) is 0.0167086. Zero is a perfect circle whereas One is parabolic escape orbit and any greater becomes a hyperbola. And in the theory of the Milankovitch cycles, Earth's eccentricity varies between 0.000055 and 0.0679 over a period of 100,000 years. This affects the seasonality of planet Earth, as an extreme ellipsis can result in longer seasons. Let us assume that Earth's eccentricity today does not exist, leaving it instead in a perfectly circular orbit. What would a circular Earth orbit mean for the seasons and the climate?