Temperature gradient


Temperature gradient

In atmospheric sciences (meteorology, climatology and related fields), the temperature gradient (typically of air, more generally of any fluid) is a physical quantity that describes in which direction and at what rate the temperature changes the most rapidly around a particular location. The temperature gradient is a dimensional quantity expressed in units of degrees (on a particular temperature scale) per unit length. The SI unit is kelvin per metre (K/m).

Mathematical description

Assuming that the temperature "T" is an intensive quantity, i.e., a single-valued, continuous and differentiable function of three-dimensional space (often called a scalar field), i.e., that

:T=T(x,y,z)

where "x", "y" and "z" are the coordinates of the location of interest, then the temperature gradient is the vector quantity defined as

: abla T = egin{pmatrix}{frac{partial T}{partial x, {frac{partial T}{partial y, {frac{partial T}{partial zend{pmatrix}

Weather and climate relevance

Differences in air temperature between different locations are critical in weather forecasting and climate. The absorption of solar light at or near the planetary surface increases the temperature gradient and may result in convection (a major process of cloud formation, often associated with precipitation). Similarly, on a global and annual basis, the dynamics of the atmosphere (and the oceans) can be understood as attempting to reduce the large difference of temperature between the poles and the equator by redistributing masses of warm and cold air (and water).

Meteorological fronts are regions where the horizontal temperature gradient may reach relatively high values, as these are boundaries between air masses with rather distinct properties.

Clearly, the temperature gradient may change substantially in time, as a result of diurnal or seasonal heating and cooling for instance.

Day to day experiences and health issues

Other places where noticeable temperature gradients can be experienced include the entrance (or exits) of air conditioned shops in the summer, or the entrance of caves and other protected or poorly ventilated areas.

Rapid changes in temperature (in space or time) may cause discomfort and, in extreme cases, heat or cold stresses.

ee also

* Gradient
* Adiabatic lapse rate

References

* Edward N. Lorenz (1967) "The nature and theory of the general circulation of atmosphere", World Meteorological Organization, Publication No. 218, Geneva, Switzerland.

* M. I. Budyko (1978) "Climate and Life", Academic Press, International Geophysics Series, Volume 18, ISBN 0-12-139450-6.

* Robert G. Fleagle and Joost A. Businger (1980) "An Introduction to Atmospheric Physics", Second Edition, Academic Press, International Geophysics Series, Volume 25, ISBN 0-12-260355-9.

* David Miller (1981) "Energy at the Surface of the Earth: An Introduction to the Energetics of Ecosystems", Academic Press, International Geophysics Series, Volume 29.

* John M. Wallace and Peter V. Hobbs (2006) "Atmospheric Science: An Introductory Survey", Second Edition, Academic Press, International Geophysics Series, ISBN 0-12-732951-X.

External links

* [http://www.grida.no/climate/ipcc_tar/wg1/index.htm IPCC Third Assessment Report]


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • temperature gradient — n. the rate of temperature change, esp. with increase in altitude …   English World dictionary

  • temperature gradient — At sea, a temperature gradient is the change of temperature with depth; a positive gradient is a temperature increase with an increase in depth, and a negative gradient is a temperature decrease with an increase in depth …   Military dictionary

  • temperature gradient — noun change in temperature as a function of distance (especially altitude) (Freq. 3) • Hypernyms: ↑gradient * * * noun : the rate of change of temperature with displacement in a given direction (as with increase of height) compare lapse rate * *… …   Useful english dictionary

  • temperature gradient — temperatūros gradientas statusas T sritis fizika atitikmenys: angl. temperature gradient vok. Temperaturgradient, m rus. градиент температуры, m; температурный градиент, m pranc. gradient de température, m; gradient thermique, m …   Fizikos terminų žodynas

  • temperature gradient — Meteorol. rate of change of temperature with distance. * * * …   Universalium

  • temperature gradient — /ˈtɛmprətʃə greɪdiənt/ (say tempruhchuh graydeeuhnt) noun the rate of change of temperature with position …   Australian English dictionary

  • Temperature gradient gel electrophoresis — (TGGE) and Denaturing Gradient Gel Electrophoresis (DGGE) are forms of electrophoresis which use either a temperature or chemical gradient to denature the sample as it moves across an acrylamide gel. TGGE and DGGE can be applied to nucleic acids… …   Wikipedia

  • temperature-gradient zone melting — temperatūrinis gradientinis zoninis lydymas statusas T sritis radioelektronika atitikmenys: angl. temperature gradient zone melting vok. Zonenschmelzen mit Temperaturgradient, n rus. зонная плавка с температурным градиентом, f pranc. fusion de… …   Radioelektronikos terminų žodynas

  • vertical temperature gradient — vertikalusis temperatūros gradientas statusas T sritis ekologija ir aplinkotyra apibrėžtis Oro temperatūros kritimas vertikalia kryptimi. Troposferoje temperatūros gradientas vertical temperature gradient0,65 °C kas 100 m aukštyn. atitikmenys:… …   Ekologijos terminų aiškinamasis žodynas

  • neutral temperature gradient — neutralusis temperatūros gradientas statusas T sritis apsauga nuo naikinimo priemonių apibrėžtis Atmosferos žemutinių sluoksnių būsena, kai maždaug vienoda oro sluoksnių temperatūra; oro vertikaliojo stabilumo laipsnis. Neutralusis temperatūros… …   Apsaugos nuo naikinimo priemonių enciklopedinis žodynas


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.