watertemperature

Water temperature is a measure of how hot or cold water is. It is a physical property that affects water density, viscosity, dissolved gas solubility, and reaction rates. Temperature is commonly expressed in degrees Celsius, degrees Fahrenheit, or Kelvin. In natural environments, water temperature varies with latitude, depth, season, and weather, and it can change rapidly in shallow or well-mixed systems.

Temperature measurements are made with thermometers, thermistor probes, thermocouples, or remote sensing methods. In oceans, surface temperature responds to solar heating and air temperature, while deeper layers reflect longer-term heat content. Freshwater bodies may exhibit thermal stratification in warm seasons, forming a warm upper layer over a cooler bottom layer, with mixing during turnover in spring and autumn.

Temperature influences ecological and biological processes. Warmer water holds less dissolved oxygen, can accelerate metabolism and growth of warm-water species, and can shift community composition. It is a key variable in fisheries management, aquaculture, and habitat suitability. Temperature also serves as a climate and environmental indicator; long-term changes in sea surface or lake temperature track climate variability and global warming.

In practical terms, water temperature is monitored for industrial cooling, heating, and process control; in fisheries and aquaculture to optimize growth; and in environmental monitoring to assess ecosystem health. Standard reference points include the freezing point of freshwater at 0 C and about -2 C for seawater, and the boiling point of water at 100 C at sea level, with small adjustments for pressure and salinity.