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Re: Meteorology B
Posted: December 7th, 2015, 4:03 pm
by sciolyFTW_aku
Thanks m8
Re: Meteorology B
Posted: December 7th, 2015, 8:26 pm
by MrHaleStorm1
Degree Day: They way I understand it is like this.
Your house inside is 70 F outside is 50 F. That is a 20 degree difference. 1 20 degree heating day. because your home had to expend energy to keep it at 70 as it would naturally drop to 50 without turning the furnace on. If this stayed this way for 30 days, you would have 20 degree days x 30 days or 600 degree days. Now if you insulated your home the next year and the temperature variances were the same you would expect to have expended less energy. Basically looking at energy expenditure to degree days as a way of measuring energy efficiency. That's my interpretation Link below was helpful.
http://www.degreedays.net/introduction
Re: Meteorology B
Posted: December 7th, 2015, 8:29 pm
by sciolyFTW_aku
Thanks man.
Re: Meteorology B
Posted: December 8th, 2015, 9:30 am
by mcsittel
Here is an explanation of degree days.
From a meteorological standpoint, degree days are defined with respect to 65 F as a reference point. The National Weather Service calculates it as follows:
The daily high and low temperature, both measured to the nearest whole degree Fahrenheit, are averaged. If the average is not an integer, it is rounded up. Subtract this average from 65. If it is a positive quantity, it is the number of COOLING degree days for that day. If it is negative, its absolute value is the number of HEATING degree days.
As an example, yesterday in Omaha, Nebraska the high was 55 and the low 28. Averaging those two numbers:
Average = (High + Low)/2 = (55 + 28)/2 = 83/2 = 41.5. We need to round this up to 42 (it is always rounded up).
Degree Days = Average - 65 = 42 - 65 = -23. It's negative so yesterday there were 23 HEATING degree days in Omaha.
Degree days are reported daily in climate summaries issued by the National Weather Service. Monthly and yearly sums of the daily degree days are also reported. Counts for heating and cooling degree days are kept separate.
Note: the "year" for heating degree days is typically that sum from the period July 1-June 30, while cooling runs from January 1-December 31.
Degree days can be calculated with other reference values than 65, but the National Weather Service standard is 65 degrees.
Re: Meteorology B
Posted: December 8th, 2015, 2:18 pm
by MrHaleStorm1
Thank you!
mcsittel wrote:Here is an explanation of degree days.
From a meteorological standpoint, degree days are defined with respect to 65 F as a reference point. The National Weather Service calculates it as follows:
The daily high and low temperature, both measured to the nearest whole degree Fahrenheit, are averaged. If the average is not an integer, it is rounded up. Subtract this average from 65. If it is a positive quantity, it is the number of COOLING degree days for that day. If it is negative, its absolute value is the number of HEATING degree days.
As an example, yesterday in Omaha, Nebraska the high was 55 and the low 28. Averaging those two numbers:
Average = (High + Low)/2 = (55 + 28)/2 = 83/2 = 41.5. We need to round this up to 42 (it is always rounded up).
Degree Days = Average - 65 = 42 - 65 = -23. It's negative so yesterday there were 23 HEATING degree days in Omaha.
Degree days are reported daily in climate summaries issued by the National Weather Service. Monthly and yearly sums of the daily degree days are also reported. Counts for heating and cooling degree days are kept separate.
Note: the "year" for heating degree days is typically that sum from the period July 1-June 30, while cooling runs from January 1-December 31.
Degree days can be calculated with other reference values than 65, but the National Weather Service standard is 65 degrees.
Re: Meteorology B
Posted: December 8th, 2015, 5:06 pm
by sciolyFTW_aku
mcsittel wrote:Here is an explanation of degree days.
From a meteorological standpoint, degree days are defined with respect to 65 F as a reference point. The National Weather Service calculates it as follows:
The daily high and low temperature, both measured to the nearest whole degree Fahrenheit, are averaged. If the average is not an integer, it is rounded up. Subtract this average from 65. If it is a positive quantity, it is the number of COOLING degree days for that day. If it is negative, its absolute value is the number of HEATING degree days.
As an example, yesterday in Omaha, Nebraska the high was 55 and the low 28. Averaging those two numbers:
Average = (High + Low)/2 = (55 + 28)/2 = 83/2 = 41.5. We need to round this up to 42 (it is always rounded up).
Degree Days = Average - 65 = 42 - 65 = -23. It's negative so yesterday there were 23 HEATING degree days in Omaha.
Degree days are reported daily in climate summaries issued by the National Weather Service. Monthly and yearly sums of the daily degree days are also reported. Counts for heating and cooling degree days are kept separate.
Note: the "year" for heating degree days is typically that sum from the period July 1-June 30, while cooling runs from January 1-December 31.
Degree days can be calculated with other reference values than 65, but the National Weather Service standard is 65 degrees.
Thanks!
Re: Meteorology B
Posted: December 16th, 2015, 2:39 pm
by MrHaleStorm1
I thought this was a pretty good, general overview for newbies in Everyday Weather
https://www.youtube.com/watch?v=WXuGYSM2D8k
Re: Meteorology B
Posted: January 22nd, 2016, 7:00 am
by MrHaleStorm1
Are questions about lighting and thunderstorms fair game this year? Seems more like "Severe Storms" but I have encounter several so far. First 2 invites, test writers were in love with the Stuve and Skew-T. Heavily weighted. On a positive note, the Stuve On a positive, the Stuve was the same exact on you always see from Plymouth State, July 21, 2004. It's like its the only one in print. Still don't complete get saturation mixing ratios. Anyone have a simple explanation for them? Also, isn't a Chinook just a Foehn wind of the Rockies? If so, shouldn't the definition be basically the same other than a geographic reference? Thanks.
Re: Meteorology B
Posted: January 24th, 2016, 8:34 am
by Skink
The rules overlap with the other years' topics, but I see anything stormy as seriously stretching it and am not bothering preparing my teams in that way, personally. As for the chinook deal, that's what the textbook reference I'm using suggests, and Wikipedia agrees.
Re: Meteorology B
Posted: February 4th, 2016, 9:22 pm
by MrHaleStorm1
There was a "Degree Heating" story problem on the Solon Invitation (Ohio). Basically it asked us to calculate the energy savings year over year due to insulating home, even though there was a difference in total degree cooling days year over year. What are some interesting topics you(group) have seen this year? Thanks
I will paraphrase the problem from what I remember
2014 Bob spent $1,800 ($.15 per kilo-watt/hr is the fixed cost of power for the problem) and had 9,250 heating degree days 12,000 kilo-watt/hrs of power
In 2015 he spent $500 to add additional insulation to his home.
In 2015 Bob used 15,000 kilo-watt/hrs of power and there were 16,500 degree heating days
1) what was Bob's heating cost in 2015
2) What would it had been if he didn't add insulation
3) Including the $500 investment of insulation, what was Bob's energy savings in 2015? Good Luck