Hot spring

File:HotSpring 8344.jpg
Hot spring in Lassen Volcanic National Park

A hot spring is a spring produced by the emergence of geothermally heated groundwater from the Earth's crust. Hot springs are in many places, especially in mountains.


There is no universally accepted definition of a hot spring. For example, one can find the phrase hot spring defined as

  • any geothermal spring [1]
  • a spring with water temperatures above its surroundings [2][3]
  • a spring with water temperatures above 50 °C (122 °F) [4]
  • a natural spring with water temperature above body temperature – normally between 36.5 and 37.5 °C (97.7 and 99.5 °F) [5][6][7][8][9]
  • a natural spring of water greater than 21.1 °C (70 °F) (synonymous with thermal spring) [10][11][12][13]
  • a natural discharge of groundwater with elevated temperatures [14]

Sources of heat

The water issuing from a hot spring is heated by geothermal energy, i.e., heat from the Earth's mantle.

Related pages


  1. "MSN Encarta definition of hot spring". Archived from the original on 2009-10-31.
  2. Miriam-Webster Online dictionary definition of hot spring
  3. For example, ambient ground temperature is usually around 55–57 °F (13–14 °C) in the eastern United States
  4. US NOAA Geophysical Data Center definition
  5. Wordsmyth definition of hot spring
  6. American Heritage dictionary, fourth edition (2000) definition of hot spring
  7. Infoplease definition of hot spring
  8. Random House Unabridged Dictionary, © Random House, Inc. 2006. definition of hot spring
  9. Allan Pentecost, B. Jones, R.W. Renaut (2003). "What is a hot spring?". Can. J. Earth Sci. 40 (11): 1443–6. doi:10.1139/e03-083.  provides a critical discussion of the definition of a hot spring.
  10. Wordnet 2.0 definition of hot spring
  11. Ultralingua Online Dictionary definition of hot spring
  12. Rhymezone definition of hot spring
  13. Lookwayup definition of hot spring
  14. Columbia Encyclopedia, sixth edition, article on hot spring