I have a datalogger which records the amount of time the sensor is below
freezing, this is quoted in either hours / minutes or Days / Hours /
Minutes. I would be interested to know how other people calculate this data.
The figures I have for February for my station are

Hours Minutes
08 18 01-03 Feb
35 43 03-10th
63 06 10-17th
37 12 17-24th
11 08 24-29th

Which gives me a total of 155hrs 27min.

Regards

Richard
West Sussex.

On Tue, 4 Mar 2008 at 14:28:48, Richard Griffith
wrote in uk.sci.weather :

I have a datalogger which records the amount of time the sensor is below
freezing, this is quoted in either hours / minutes or Days / Hours /
Minutes. I would be interested to know how other people calculate this data.
The figures I have for February for my station are

Hours Minutes
08 18 01-03 Feb
35 43 03-10th
63 06 10-17th
37 12 17-24th
11 08 24-29th

Which gives me a total of 155hrs 27min.

My datalogger doesn't automatically calculate this, but Excel crunches
the numbers easily.

I recorded 113hrs 25min below freezing last month.
--
Paul Hyett, Cheltenham (change 'invalid83261' to 'blueyonder' to email me)

"Richard Griffith" wrote in message
...
I have a datalogger which records the amount of time the sensor is below
freezing, this is quoted in either hours / minutes or Days / Hours /
Minutes. I would be interested to know how other people calculate this
data. The figures I have for February for my station are

Hours Minutes
08 18 01-03 Feb
35 43 03-10th
63 06 10-17th
37 12 17-24th
11 08 24-29th

Which gives me a total of 155hrs 27min.

Regards

Richard
West Sussex.


An earlier version of Davis Weatherlink had a module which would output this
information. Later versions did not offer this so I continued to run two
versions of Weatherlink. In the end it was more trouble than it was worth
given the limited amount of air frost we have here. Now I just look at the
graphs, browse the records and work it out from there. Generally
straightforward but on those nights where the temperature dithers around
freezing it can be a pain.

All the best
--
George in Epping, West Essex (107m asl)
www.eppingweather.co.uk
www.winter1947.co.uk
COL 36055

On 4 Mar, 14:28, "Richard Griffith" wrote:
I have a datalogger which records the amount of time the sensor is below
freezing, this is quoted in either hours / minutes or Days / Hours /
Minutes. I would be interested to know how other people calculate this data.
The figures I have for February for my station are

Hours * Minutes
08 * * * *18 * * * * * *01-03 Feb
35 * * * *43 * * * * * *03-10th
63 * * * *06 * * * * * *10-17th
37 * * * *12 * * * * * *17-24th
11 * * * *08 * * * * * *24-29th

Which gives me a total of 155hrs 27min.

Regards

Richard
West Sussex.

I take it from my 5 min CR10X data spreadsheet: if 5 min mean temp =
0.0°C then no frost, if = -0.1 then count 5 min frost, sum for the
day then convert to hours and tenths for the daily and monthly
totals.

My Feb 08 total 127.5 h: annual average 1995-2007 404 h here. In Feb
1986 alone my total was 441 h, in those days painstakingly taken from
thermograph chart.

--
Stephen Burt
Stratfield Mortimer, Berkshire

Which model does your datalogger work with? Neither Instromet (Met4Net) or
Davis Weatherlink appear to offer this. However, we work out air frost
duration directly from a thermograph plot.

Regards

Mike

Pitsford Hall weather station
www.northantsweather.org.uk


"Richard Griffith" wrote in message
...
I have a datalogger which records the amount of time the sensor is below
freezing, this is quoted in either hours / minutes or Days / Hours /
Minutes. I would be interested to know how other people calculate this
data. The figures I have for February for my station are

Hours Minutes
08 18 01-03 Feb
35 43 03-10th
63 06 10-17th
37 12 17-24th
11 08 24-29th

Which gives me a total of 155hrs 27min.

Regards

Richard
West Sussex.

Richard Griffith wrote:
I have a datalogger which records the amount of time the sensor is below
freezing, this is quoted in either hours / minutes or Days / Hours /
Minutes. I would be interested to know how other people calculate this data.
The figures I have for February for my station are

Hours Minutes
08 18 01-03 Feb
35 43 03-10th
63 06 10-17th
37 12 17-24th
11 08 24-29th

Which gives me a total of 155hrs 27min.

Something I've been meaning to add to my Canterbury site for a while
now. I have added the data into the database by counting the number of
5-minute data points below 0C and multiplying by 5 to get a rough
estimate. This is likely to over-read by a few minutes but not
significantly over the period of a day (and within the accuracy of the
temperature sensor anyway).

I've added a column to the month tables:
http://www.canterburyweather.co.uk/m...th=2&year=2008

February 2008 totals 106h 20m by my method.

--
Jonathan Stott
Canterbury Weather: http://www.canterburyweather.co.uk/
Reverse my e-mail address to reply by e-mail