Saturday, 27 March 2010

Daylight saving

Why must we wait so long to start saving daylight? When we put the clocks back on 31st October there were only 9 hours 45 minutes from sunrise to sunset (on the latitude of London). Tomorrow, 28th March, there will be 12 hours 40 minutes - nearly three hours more! 31.10 was only 51 days away from midwinter, tomorrow will be 80 days away.

It gets stranger. Evening sunlight, which is what we are supposed to be increasing, ended at 4.36 GMT on 31.10. Today it ends at 6.26, which will become 7.26. Part of the difference is because our clocks do not follow sundial time. True noon today (when the sun reaches its highest point) is at 12.6 by the clock; it was at 11.43 on 31.10. So the shifting of noon has already added 23 minutes to the afternoon since the clocks went back.

These odd dates were fixed by some committee many years ago, and now they are just adjusted each year to make them fall on a Sunday. Meanwhile the climate has changed, and March is warmer than it used to be (though this year cold weather lasted longer than usual), so please can the committee meet again and throw light on this matter?

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