Evaporation From Soils

Recently I went back to be interested in evapotranspiration, and I was captured by a thread of publication by Dani Or (GS) and Peter Lehmann and coworkers on the subject. Fortunately, Dany also gave some talk on the same subject that can help to understand the papers.
Some of the main results: 1 - when evaporating from soil the Kelvin effect is not so important. 2 - What is important is the ability of the porous medium to supply water through capillary flows. 3 - The decline of evaporation (a.k.a. stage II evaporation) happens when the vadose zone is made up of disconnected phases. 4 - The latter situation is realised when the evaporating front is at a depth that can be deduced directly from the Soil Water Retention Curves.

Here the talks by Dany:

- The first, longer talk, given at usaskgiws, the University of Saskatchewan (1 h);
- The second one, shorter given at the recent Ecohydrology conference.

Here the papers:

Aminzadeh, M., & Or, D. (2013). Temperature dynamics during nonisothermal evaporation from drying porous surfaces. Water Resources Research, 49(11), 7339–7349. doi:10.1002/2013WR014384

Assouline, S., & Or, D. (2013). Plant Water Use Efficiency over Geological Time – Evolution of Leaf Stomata Configurations Affecting Plant Gas Exchange. PLoS ONE, 8(7), e67757. 

doi:10.1371/journal.pone.0067757

Haghighi, E., Shahraeeni, E., Lehmann, P., & Or, D. (2013). Evaporation rates across a convective air boundary layer are dominated by diffusion. Water Resources Research, 49(3), 1602–1610. doi:10.1002/wrcr.20166

Lehmann, P., & Or, D. (2014). Effect of wetness patchiness on evaporation dynamics from drying porous surfaces, 1–13. doi:10.1002/wrcr.20637

Or, D., Lehmann, P., & Shahraeeni, E. (2014). Advances in soil evaporation Physics - A review. Vadose Zone Journal, 1–16.