209:. Since the escape or ingress of heat due to conduction is proportional to the difference between the indoor and outdoor temperature, the amount of energy needed to maintain the base temperature indoors for some period of time is roughly proportional to the number of degree days. For example, if the base temperature is 18 °C (64 °F) and the outdoor temperature is constant at 10 °C (50 °F) for one day, this counts as 8 degree days (14 degree days in Fahrenheit). Note that the base temperature used for these calculations is 2–3 °C (3.6–5.4 °F) lower than a typical indoor temperature setting, since a building will naturally be slightly warmer than the surrounding air due to body heat of its occupants and absorption of solar radiation.
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Growing degree days are based on 5 °C, given that typical plant growth stops below that temperature. Plant growth has been observed to be correlated to the number of degree days. Many plants will fruit after a certain number of degree days. Common examples are strawberries and raspberries. In
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The heating and cooling degree days are tallied separately to calculate monthly, seasonal, and yearly total heating and cooling degree days. Heating and cooling degree days closely correlate with heating and cooling demand.
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is when either heating or cooling consumption is at a minimum, which is useful with power utility companies in predicting seasonal low points in energy demand.
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Degree days are a useful metric for estimating energy consumption required for household heating and cooling, and in this context are formally referred to as
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If the mean daily temperature is above 65 °F, the mean degrees
Fahrenheit above 65 °F are counted as the cooling degree day.
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If the mean daily temperature is below 65 °F, the mean degrees
Fahrenheit below 65 °F are counted as the heating degree day.
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higher than the corresponding degree day (1 Celsius degree-day is 8.64×10 K·s; 1 Fahrenheit degree-day is 4.8×10 K·s).
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emerge and vanish. But in order to chart the actual growth of insects, degree days above freezing are used.
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equal to the day's temperature variation, measured from max and min, and totalling the daily results;
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As previous, but with modified formulae on days when the max and min straddle the base temperature.
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or cooling. Total degree days from an appropriate starting date are used to plan the planting of
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As above, but calculating the daily difference between mean temperature and base temperature;
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Free degree day downloads for 77 UK weather stations and various building base temperatures
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contrast, deterministic plants will fruit based on the time of year, which the plant
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Frequent measurements and continuously integrating the temperature deficit or excess;
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http://www.enr.gov.nt.ca/sites/enr/files/wildlife_manuscript_report_246.pdf
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The paper referenced shows the complexity of plant growth and degree days.
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buildings, while annual figures can be used for estimating future costs.
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If the mean daily temperature is 65 °F, no degree days are counted.
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timing. Weekly or monthly degree-day figures may also be used within an
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In Canada, Growing Degree Days are used in order to predict when
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Government of Canada, Public
Services and Procurement Canada.
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385:"Degree-days - U.S. Energy Information Administration (EIA)"
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determines from the number of consecutive hours of dark
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122:A map of France which shows the different zones
417:Information relating to plant and pest growth
180:Treating each day's temperature profile as a
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106:Learn how and when to remove this message
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44:adding citations to reliable sources
353:"Information archivée dans le Web"
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254:In the United States, the mean (
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442:Building thermal regulations
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452:Atmospheric thermodynamics
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447:Energy conservation
315:orders of magnitude
218:Growing degree days
207:heating degree days
360:publications.gc.ca
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327:Growing degree day
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96:January 2021
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55:"Degree day"
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38:Please help
33:verification
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389:www.eia.gov
167:temperature
426:Categories
394:2020-11-29
338:References
244:blackflies
240:mosquitoes
128:degree day
66:newspapers
259:max + min
234:Black Fly
186:amplitude
182:sine wave
321:See also
159:integral
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132:heating
80:scholar
311:kelvin
307:second
213:Canada
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