New Zealand Local Weather Forum

Climate and Science => Space, Science and Nature => Topic started by: JennyLeez on March 20, 2012, 04:20:33 PM

Title: Autumn Equinox at 6:14pm 20th March 2012
Post by: JennyLeez on March 20, 2012, 04:20:33 PM
At precisely 6:14 this evening the Autumn Equinox will occur - and for the next 6 months the sun will spend more time shining over the Northern Hemisphere as we head towards winter.

For many people today is officially the change of season from summer to autumn in New Zealand and across the world March 20th will herald the end of winter in the northern hemisphere.

The shortest day is exactly 12 weeks away today. 

By the end of this week the nights will be longer than the days - currently they are equal in length.

It has become increasingly obvious that evenings and mornings are drawing in and now there are less than two weeks to go until daylight savings ends and our clocks go back one hour - giving us an extra hours sleep in.

The 3 months with the least amount of sunlight begins in 6 weeks time, sometimes referred to as the solar winter.
Weatherwatch
Title: Re: Autumn Equinox at 6:14pm 20th March 2012
Post by: Rwood on March 20, 2012, 04:39:27 PM
Everyone should note the often-missed point that at the equinox the daylength is about 12 hours 7 minutes, the extra coming from refraction in the main.
Title: Re: Autumn Equinox at 6:14pm 20th March 2012
Post by: ato2 on March 26, 2012, 10:48:44 AM

Yes, I get people saying how come the day isn't 12 hrs exactly...
Title: Re: Autumn Equinox at 6:14pm 20th March 2012
Post by: Rwood on March 26, 2012, 11:04:27 AM
I should add that the length is greater as latitude increases - over 12 h 10m at London, and about 12 h 16m at Helsinki.