A unit that represents one degree of deviation from a reference point in the mean daily outdoor temperature (usually 65°F) and that is used to measure heating and cooling requirements.
A unit of heat. The equivalent of one degree of temperature, maintained for 24 hours, above or below any specified base temperature, e.g., 2° for 12 hours or 0.5° for 48 hours. Often used in predicting the time of incidence of insect pests in the spring. For purposes of plant growth and animal development, the base temperature may be the temperature above which growth can be initiated and maintained.
One degree of temperature above an insect's developmental threshold, lasting for one day. It is the most common method of expressing heat units.
a heat unit calculated on a daily basis, usually using the daily max and min temperature
Difference between the average daily temperature and 65 degrees. When the average temperature is greater than 65, the degree days are called "cooling" If the average temperature is less than 65 they are referred to as "heating" (HDD).
The difference between the average daily temperature and 50 degrees, if this difference is greater than 0, is called a growing degree day (GDD). When the average temperature is less than 50, there are 0 GDDs for that day.
A unit measuring the extent to which the outdoor mean (average of maximum and minimum) daily dry-bulb temperature falls below or rises above an assumed base. The base is normally taken as 65 degrees Fahrenheit for heating and for cooling unless otherwise designated. One degree-day is counted for each degree below (deficiency heating) or above (excess cooling) the assumed base, for each calendar day on which such deficiency or excess occurs.
A degree-day is a computation that gauges the amount of heating or cooling needed for a building. A degree-day is equal to 65 degrees Fahrenheit minus the mean outdoor temperature.
Gauges the amount of heating or cooling needed for a building using 65 degrees as a baseline. To compute heating/cooling degree-days, the average temperature is taken and referenced to a base line of 65 degrees. An average temperature of 50 yields 15 heating degree-days while an average of 75 would yield 10 cooling degree-days. Electrical, natural gas, power, heating, and air conditioning industries utilize heating and cooling degree information to calculate their needs.
Calculated by subtracting the average outdoor temperature for an area from 65º Fahrenheit. This measurement is used to estimate the amount of heating or cooling a home or building will need.
a measure of the variation of one dayâ€(tm)s temperature against a standard reference temperature, typically 65Â° Fahrenheit (18Â° Celsius). Degree-days are used as a basis for temperature-related weather derivative deals. There are both cooling degree-days (CDDs) and heating degree-days (HDDs). For example, a firm takes out a 30-day CDD swap with a reference temperature of 65Â°F, and the average temperature on each day is 70Â°F. The company is then due 150 (30 x 5) degree-days multiplied by the sum of money agreed for each degree-day. If the firm had taken out an HDD swap, it would have owed the same amount of money.
A unit that represents a 1 degree F deviation from some fixed reference point (usually 65 degrees F) in the mean, daily outdoor temperature.
A unit measuring the extent to which the outdoor mean (average of maximum and minimum) daily dry-bulb temperature falls below (in the case of heating) or rises above (in the case of cooling) an assumed base. The base is normally taken as 65 degrees for heating and cooling unless otherwise designated.
A derived unit of measurement used to express the departure of the mean temperature for a day from a given reference temperature. Also see freezing index and thawing index.
a unit combining time and temperature, used to measure the development of an organism from one point to another in its life cycle.
A unit of measure representing one degree of declination from a standard temperature in the average temperature of one day, used in determining fuel needed to maintain a given temperature between the mean and 65 degrees over 24 hours requirements.
A rough measure used to estimate the amount of heating required in a given area; is defined as the difference between the mean daily temperature and 65 degrees Fahrenheit. Degree-days are also calculated to estimate cooling requirements.