As a result, Earth is moving at its fastest orbital velocity at the January perihelion—around 30.3 km/s (about 67,700 mph)—and at its slowest at the July aphelion, moving about 1 km/s slower. This variation in speed has a subtle impact on the length of our seasons. In the Northern Hemisphere, winter (which occurs near perihelion) is the shortest season because the planet is moving fastest.
Earth at perihelion – closest to sun – on January 3 - EarthSky during which month is the earth closest to the sun link
The Seasons, the Equinox, and the Solstices - National Weather Service As a result, Earth is moving at its