In a year that’s gotten off to a bit of a shaky start, an early spring could only be a good thing, right? While there’s not much we can do about the weather, we can always frame the situation in its best light.

On March 1, we can welcome the first day of what climatologists and weather folks term meteorological spring. According to their way of looking at things, the seasons are three-month periods best broken down according to the annual temperature cycle, hence winter is December, January and February; spring is March, April and May; summer is June, July and August; September, October and November are the months of autumn.

This logic contradicts much of our school learning, in which we are drilled that seasons change with the coming of the solstices (usually June 21 and Dec. 21) and equinoxes (usually March 20 and Sept. 22 or 23). Astronomical seasons are based on the Earth’s position in relation to the sun, meaning the seasons change on the longest and shortest days of the year, as well as the two days at which the hours of sunlight and darkness are nearly the same at all latitudes.

There are certain advantages to the meteorological season. Because Earth completes its journey around the sun not in a perfect year but a fraction over it (365.256 days, to be more exact), we need to add an extra day to the calendar every fourth year, creating what we refer to as Leap Years. This phenomenon means the exact dates of the solstices and equinoxes vary slightly from year to year. And as the earth’s orbit around the sun is not a perfect circle but an ellipse, the lengths of the astronomical seasons vary between 89 and 94 days.

These variations in the length of seasons and their start dates make it difficult to compare climatological statistics from one year to the next. The meteorological seasons offer us much more consistency in this regard. By this reckoning, there are 90 days of winter, 92 days of spring, 92 days of summer, and 91 days of fall.

The meteorological season also more accurately reflects our expectations as to what the weather should be like. The 90 coldest and 90 hottest days of the year usually fall closer to the meteorological seasons than the astronomical ones.

Another obvious advantage to meteorological seasons is their alignment with entire months, meaning monthly statistics are easily folded into seasonal ones.

In short: Love spring? Call March 1 your happy day! Hate to see the summer go? Turn to the astronomical calendar and consider the first three weeks of September your bonus allotment of sunshine and good vibes.