meanDailyTemp

MeanDailyTemp, often abbreviated as mean daily temperature or meanDailyTemp, is a meteorological variable representing the average air temperature over a calendar day at a given location. It is used to summarize daily thermal conditions and to compute longer-term climate normals and various weather indices.

Calculation and methods: When hourly temperature data are available, meanDailyTemp is the arithmetic average of the 24 hourly mean temperatures. In many historical data sets, daily mean is estimated as the average of the daily maximum and minimum temperatures (Tmean ≈ (Tmax + Tmin)/2), an approximation that assumes a roughly linear temperature change over the day. Some data products provide Tmean directly from continuous measurements or quality-controlled stations.

Units and representation: MeanDailyTemp is commonly expressed in degrees Celsius (°C) or degrees Fahrenheit (°F); scientific contexts may use kelvin (K). Values reflect the overall thermal condition of the day rather than the extremes.

Applications: This metric supports climate normals (such as 30-year means), trend analyses, agricultural planning (growing degree days), energy demand modeling, and weather risk assessments. It is also used to evaluate heat exposure and urban heat island effects when averaged over regions.

Data sources and quality: MeanDailyTemp is derived from ground-based weather stations, gridded climate datasets, and reanalysis products. Data gaps, station relocations, and urbanization can introduce biases, so quality control and homogenization are important for accurate comparisons.

Limitations: The mean may mask diurnal extremes; the chosen calculation method can influence results, particularly in environments with rapid temperature changes or unusual cloud patterns.

See also: Daily maximum and minimum temperature, diurnal temperature range, climate normal, growing degree days.