In the context of the environment, "mean" can refer to the average or expected value of a particular measurement or characteristic. For example, a researcher might calculate the mean value of a particular environmental variable, such as temperature or pH, in order to understand the overall trend or pattern of that variable over time.
Mean temperature: The average temperature of a particular location or region over a given period of time. Mean temperature can be calculated by taking the sum of the temperature readings for a given period of time, and then dividing that sum by the number of readings.
Mean sea level: The average height of the surface of the sea relative to a reference level, such as a tidal datum or a particular land elevation. Mean sea level can be affected by a variety of factors, including changes in temperature and the melting of glaciers and ice sheets.
Mean annual precipitation: The average amount of precipitation (such as rain or snow) that falls in a particular location or region over a one-year period. Mean annual precipitation can be calculated by taking the sum of the precipitation readings for a given period of time, and then dividing that sum by the number of readings.