Mean Temperature The average of a series of temperatures taken over a period of time, such as a day or a month.
Measurable Precipitation of 0.01" or more.
Medium Range In forecasting, (generally) three to seven days in advance.
The average of temperature readings taken over a specified amount of time. Often the average of the maximum and minimum temperatures.
MEASURED CEILING ...
Daily Mean Temperature - The mean temperature for a day that is determined by averaging the hourly readings or
more commonly, by averaging the maximum and minimum temperatures for a day.
Mean temperature The average temperature of the air as indicated by a properly exposed thermometer for a given time period, usually a day, a month, or a year.
THICKNESS The thickness of a layer in the atmosphere is proportional to the mean temperature of that whole layer. The layer most often used in meteorology is between 1000 and 500 millibars.
Typically, heating degree days are calculated as how much colder the mean temperature at a location is than 65°F on a given day.
degree-day (C or F) a derived unit of measurement used to express the departure of the mean temperature for a day from a given reference (or base) temperature.
This is done by drawing a line through geographic points where the mean temperature for the warmest month (usually July) is equal to 51.4 - 0.1k, where k is equal to the mean temperature of the coldest month (usually January).
, 1953: The mean temperature of Central England, 1698 to 1952. Quart J Roy Meteorol Soc, 79, 242-261.
Manley, G. 1974: Central England Temperatures: monthly means 1659 to 1973. Quart J Roy Meteorolol Soc, 100, 389-405.
Parker, D. E., T. P.
As already noted elsewhere, the values of the (total) thickness between levels at 500hPa and 1000hPa give a useful measure of the mean temperature of that layer.
Degree Day- a measure of the departure of the daily mean temperature from the normal daily temperature; heating and cooling Degree Days are the departure of the daily mean temperature from sixty-five degrees Fahrenheit.
Computed from each day's mean temperature (max+min/2). For each degree that a day's mean temperature is below or above a reference temperature is counted as one degree day.
COOLING DEGREE DAY A cooling degree day is given for each degree that the daily mean temperature departs above the baseline of 75 degrees Fahrenheit.
Temperature variations over Australia during the past century have been consistent with global trends in showing an increase in the mean temperature (average of daytime maximum and overnight minimum temperatures) over most of the continent.
Monthly Climatic Data of the World (MCDW): This National Climatic Data Center (NCDC) publication contains monthly mean temperature, pressure, precipitation, vapor pressure, and sunshine for approximately 2, ...
A cooling degree day is given for each degree that the daily mean temperature departs above the baseline of 75 degrees Fahrenheit.
The term refers to the mean temperature of the ocean in the upper few meters.
Hypsithermal - An extended mild episode between about 5000 and 7000 years ago when global mean temperature was somewhat higher (perhaps 1 Celsius degree) than at present.
Sea Surface Temperatures (SSTs) - The term refers to the mean temperature of the ocean in the upper few meters.
However charts are also produced for thicknesses of other layers in the atmosphere as well. The thickness gives an indication of the mean temperature within a layer; lower thicknesses indicate colder air, higher thicknesses warmer air.
For example, if some location had a mean temperature of 60oF on day 1 and 80oF on day 2, there would be 5 HDD's for day 1 (65 minus 60) and 0 for day 2 (65 minus 80, set to 0). For the day 1 + day 2 period, the HDD total would be 5 + 0 = 5.
Due to the paucity of data in the Southern Hemisphere, recent studies have emphasized the reconstruction of Northern Hemisphere (NH) mean, rather than global mean temperatures over roughly the past 1000 years.
See also: Temperature, Surface, Atmosphere, Weather, Water