Kent/E. Sussex - "An Hell of Ashdown" - 66 miles - Sat 8th December

[GrumpyGregry]

I've got a phone!

But it's not charged yet.

When are you planning on catching some zzz Greg?

It's the lack of sleep that gives me such a happy positive disposition. Bed at 2300, up at 0500.

 

[GrumpyGregry]

How does that work with frost hollows then? Sometimes on night rides we can feel the temperature dropping as lanes dip down?

Frost hollows explained

There are some real humdingers on the Powys/Shropshire borders. I've seen a 10 degree drop on the car thermometer.

 

[GrumpyGregry]

That's what I thought @GregCollins, so if cold air drops down how can temperatures fall 3 degrees per 1000 feet of ascent, as per @mmmmartin's post? I dunno. It's wishful thinking I reckon, and given the last few mornings I think I'll predict, without looking at any weather sites at all, that it's going to be farking freezing tomorrow early.

Have a good ride everyone and stay safe. We've had miles too many fractures around here lately.

good article on lapse rate on wikipedia

"Although the actual atmospheric lapse rate varies, under normal atmospheric conditions the average atmospheric lapse rate results in a temperature decrease of 3.5°F/1,000 ft (6.4°C/km) of altitude."

so the splendid mmmmartin was right and wrong all at once having mixed his F's with his C's.

 

[benborp]

There are two effects. One is the heat sink nature of the Earth. It radiates this stored heat and the effect is more pronounced the lower you are. This works on a larger scale than frost hollows.

The other is air pressure. The pressure drops as elevation increases. In effect the warmth of the air is spread more thinly through a larger volume.

 

[srw]

There are two effects. One is the heat sink nature of the Earth. It radiates this stored heat and the effect is more pronounced the lower you are. This works on a larger scale than frost hollows.

Wouldn't that only make a difference when you climb through the atmosphere away from the earth? Surely it wouldn't explain the fact that the top of a mountain is colder than the bottom - because the mountain acts as a heat sink in the same way as the valley floor.

 

[Shadow]

It's the lack of sleep that gives me such a happy positive disposition. Bed at 2300, up at 0500.

Such a better man than I. (agreed,not difficult). Bed now, rise later and I need to ride to the station before you leave your house... or are you riding to gatwick?! Glad you'll be happy, I cannot guarantee that I will be til much later in all likelihood. Hope to see you at 7.37ish. Nighty- night.

 

[benborp]

Wouldn't that only make a difference when you climb through the atmosphere away from the earth? Surely it wouldn't explain the fact that the top of a mountain is colder than the bottom - because the mountain acts as a heat sink in the same way as the valley floor.

The valley floor is surrounded by more heat sink Earth and there is a cumulative effect. The mountain is surrounded by air and dissipates its heat more easily. A parallel could be drawn to the heat sink effect of a modern concrete city compared to a similarly constructed university campus. The city hangs on to its heat better.

 

[benborp]

@musa Do you have a time and place that you'll be passing through?

 

[GrumpyGregry]

It's still going to be fracking freezing though

nowt wrang wi'a bit o caad, bonny lass.

 

[GrumpyGregry]

Such a better man than I. (agreed,not difficult). Bed now, rise later and I need to ride to the station before you leave your house... or are you riding to gatwick?! Glad you'll be happy, I cannot guarantee that I will be til much later in all likelihood. Hope to see you at 7.37ish. Nighty- night.

No ta. I'm already the lanterne rouge in the company I'm keeping tomorrow.

 

[GrumpyGregry]

My last words on the subject.

RIDE ON!

 

[musa]

@musa Do you have a time and place that you'll be passing through?

no, i live in brixton hill so i can ride via norwood up the hill into the one way gyratory of c palace (towards the iceland etc) or come the bus 3 route towards the bus depot

either or is good for me

 

[musa]

what route was you going through?

 

[benborp]

Croydon, Purley, Coulsdon, Portnalls Rd to Reigate then Lonesome Lane to Horley. 23 miles. Meet at The White Hart, top of the triangle, 6.30? I'll PM my mobile number.

 

[Trickedem]

Well, we have been lucky. Currently having elevenses in Groombridge. Sitting outside in the sunshine, but it is very cold.