Temperature

Temperature is the measure of intensity of heat in degrees, reflecting the kinetic energy of the matter[1]. Temperature is an important factor for many ecosystem and biological processes. Few organisms can maintain an active metabolism at very low or high temperatures. However, most biochemical and physiological processes occur at a faster rate in higher temperatures (such as faster growth rates).

Air temperature has a major influence on water temperature, and the sea absorbs heat from the atmosphere, which plays a part in influencing atmospheric events, climate patterns and ocean currents[2].

Quick facts

Temperature changes

of as little as one degree over several weeks can cause coral in marine ecosystems to expel colourful microscopic algae (zooxanthellae) - a process called coral bleaching[2]

Temperature influences many ecosystem processes and services. Riparian vegetation, and floating and emergent plants reduce water temperature through shading, and reduce fluctuations in water temperature between seasons.

Temperature affects many nutrient cycling reactions (such as nitrification and denitrification) and other cycling processes such as decomposition. Temperature also plays a significant role in waterbody stratification, by contributing to the density of water.

There are three temperature scales used, which are the Fahrenheit, Celcius and Kelvin scales. The Celcius scale is generally used for assessments and measurements in a labratory. The Celcius scale is based on the properties of water (with 0^oC being the freezing point of water, and 100^oC for the boiling point of water). The Kelvin scale however, does not go below zero and so the freezing point of water is reached at 273.15K. The lowest possible temperature on the Kelvin scale is absolute zero. In Fahrenheit, 32^oF is the freezing point and 212^oF the boiling point of pure water.

Air temperature, for the Australian Government Bureau of Meteorology, is measured in a very precise manner at many stations around Australia, at various times throughout the day and reported as maximum, minimum, average temperature and temperature anomalies.

See also 113 years of Australian temperatures, Latest Weather Observations for Queensland and Observation of air temperature.

Temperature and changes in climate

Globally, the average air temperature at the earth’s surface has warmed by over 1°C since reliable records began in 1850. Each decade since 1980 has been warmer than the last, with 2011–20 being around 0.2 °C warmer than 2001–10[3]. As concentrations of greenhouse gases (such as CO₂) increase in the atmosphere, temperatures are rising and causing changes to climate, and ultimately, how ecosystems function. Impacts include reduced streamflow and water availability for wetlands, reduced rainfall and more intense weather events, and changes to biological processes (such as changes to plant and animal life cycle processes and timing).

Major programs are underway in Queensland and Australia to address climate related issues and increase climate resilience.

Links and references

Cycles - climate and weather cycles

References

1. ^ Campbell, NA & Reece, JB (2002), Biology, p. 1247, Benjamin Cummings, San Francisco.
2. ^ a b Queensland Museum (2022), Wetlands of Queensland Book, p. 437, Queensland Museum, Brisbane, Queensland.
3. ^ State of the Climate 2022: Bureau of Meteorology. [online] Available at: http://www.bom.gov.au/state-of-the-climate/ [Accessed 13 October 2023].

Last updated: 6 September 2023