evidence: In the 1930s, Serbian mathematician Milutin Milankovitch theorized that slow changes in the way the Earth moves through space about the Sun could have influenced our planet’s climate past. The Earth has experienced a string of ice ages in the past, interrupted by shorter, warmer, interglacial periods. How –and how much– have the Earths’ orbital parameters (including eccentricity, obliquity, and precession) influenced global climate in the past? [...] Seasons and the Earth’s tilt [...] Earth’s tilt is not always precisely the same. Every 41,000 years the tilt fluctuates between 22.1 degrees and 24.5 degrees from vertical. The tilt of the earth’s axis is described by obliquity. Earth’s current angle is about 23.45 degrees, that is, we’re tilted 23.45 degrees away from a hypothetical vertical line, and we’re very slowly becoming less oblique, shrinking the angle.