A Simulation Analysis of Thermal Effects on Evaporation From Soil

A Simulation Analysis of Thermal Effects on Evaporation From Soil The Richards equation, which expresses the conservation of water in an isothermal soil, has a more general form in a nonisothermal soil. In using the latter, it is necessary to know soil temperature, and modeling becomes considerably more complicated. A detailed, numerical simulation model quantifies the thermal effects for two hypothetical soils under two climates. During characteristic 4‐day climatic sequences, in a season of soil heating, diffusion of vapor due to thermally induced vapor concentration gradients suppresses evaporation. The suppression is greatest (5–15% in this set of experiments) under arid conditions. Under these conditions, such thermal vapor diffusion also distorts the usual diurnal pattern of evaporation. Evaporation is generally more sensitive to isothermal than to thermal vapor diffusion. Variations in time and depth of the soil temperature cause corresponding variations in the water transport coefficients. These, in turn, result in biases (2–5%) and diurnal distortions of evaporation rates. Liquid flow attributable to the dependence of matric potential on temperature accounts for about 1% of evaporation in our experiments. In simulations of 1 month duration for each combination of soil and climate, the joint neglect of all thermal effects mentioned above introduces an error of only about 1% in the average evaporation rate and does not distort its time distribution significantly. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Water Resources Research Wiley

A Simulation Analysis of Thermal Effects on Evaporation From Soil

Water Resources Research, Volume 20 (8) – Aug 1, 1984

Loading next page...
 
/lp/wiley/a-simulation-analysis-of-thermal-effects-on-evaporation-from-soil-ZMukJr40Rj
Publisher
Wiley
Copyright
Copyright © 1984 by the American Geophysical Union.
ISSN
0043-1397
eISSN
1944-7973
D.O.I.
10.1029/WR020i008p01087
Publisher site
See Article on Publisher Site

Abstract

The Richards equation, which expresses the conservation of water in an isothermal soil, has a more general form in a nonisothermal soil. In using the latter, it is necessary to know soil temperature, and modeling becomes considerably more complicated. A detailed, numerical simulation model quantifies the thermal effects for two hypothetical soils under two climates. During characteristic 4‐day climatic sequences, in a season of soil heating, diffusion of vapor due to thermally induced vapor concentration gradients suppresses evaporation. The suppression is greatest (5–15% in this set of experiments) under arid conditions. Under these conditions, such thermal vapor diffusion also distorts the usual diurnal pattern of evaporation. Evaporation is generally more sensitive to isothermal than to thermal vapor diffusion. Variations in time and depth of the soil temperature cause corresponding variations in the water transport coefficients. These, in turn, result in biases (2–5%) and diurnal distortions of evaporation rates. Liquid flow attributable to the dependence of matric potential on temperature accounts for about 1% of evaporation in our experiments. In simulations of 1 month duration for each combination of soil and climate, the joint neglect of all thermal effects mentioned above introduces an error of only about 1% in the average evaporation rate and does not distort its time distribution significantly.

Journal

Water Resources ResearchWiley

Published: Aug 1, 1984

References

  • Moisture and heat transport in hysteretic, inhomogeneous porous media: A matric head‐based formulation and a numerical model
    Milly, Milly
  • A linear analysis of thermal effects on evaporation from soil
    Milly, Milly
  • A conceptual model of hysteresis
    Mualem, Mualem
  • A new model for predicting the hydraulic conductivity of unsaturated porous media
    Mualem, Mualem
  • Extension of the similarity hypothesis used for modeling the soil water characteristics
    Mualem, Mualem

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off