sentences:  Consequently, summers are warmer in the northern hemisphere than in the southern hemisphere under similar conditions.Astronomers commonly express the timing of perihelion relative to the vernal equinox not in terms of days and hours, but rather as an angle of orbital displacement, the so-called longitude of the periapsis (also called longitude of the pericenter).For the orbit of the Earth, this is called the "longitude of perihelion", and in 2000 it was about 282.895°; by the year 2010, this had advanced by a small fraction of a degree to about 283.067°.