Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 5.509 IF 5.509
  • IF 5-year value: 5.689 IF 5-year 5.689
  • CiteScore value: 5.44 CiteScore 5.44
  • SNIP value: 1.519 SNIP 1.519
  • SJR value: 3.032 SJR 3.032
  • IPP value: 5.37 IPP 5.37
  • h5-index value: 86 h5-index 86
  • Scimago H index value: 161 Scimago H index 161
Discussion papers
https://doi.org/10.5194/acp-2018-929
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-2018-929
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 26 Nov 2018

Research article | 26 Nov 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal Atmospheric Chemistry and Physics (ACP).

Identification of soil-cooling rains in southern France from soil temperature and soil moisture observations

Sibo Zhang1,a, Catherine Meurey1, and Jean-Christophe Calvet1 Sibo Zhang et al.
  • 1CNRM (Université de Toulouse, Meteo - France, CNRS) , Toulouse, France
  • anow at: Qian X uesen Laboratory of Space Technology, China Academy of Space Technology (CAST) , Beijing, China

Abstract. In this study, the frequency and intensity of soil-cooling rains is assessed using in situ observations of atmospheric and soil profile variables in southern France. Rainfall, soil temperature and topsoil volumetric soil moisture (VSM) observations, measured every 12 minutes at 21 stations of the SMOSMANIA (Soil Moisture Observing System – Meteorological Automatic Network Integrated Application) network, are analyzed over a time period of 9 years, from 2008 to 2016. The spatial and temporal statistical distribution of the observed rainfall events presenting a marked soil-cooling effect is investigated. It is observed that the soil temperature at a depth of 5cm can decrease by as much as 6.5ºC in only 12 minutes during a soil-cooling rain. We define marked soil-cooling rains as rainfall events triggering a drop in soil temperature at a depth of 5 cm larger than 1.5°C in 12 minutes. Under Mediterranean and Mediterranean-mountain climates, it is shown that such events occur up to nearly 3 times a year, and about once a year on average. This frequency decreases to about once every 3.5 years under semi-oceanic climate. Under oceanic climate, such pronounced soil-cooling rains are not observed over the considered period of time. Rainwater temperature is estimated for 13 cases of marked soil-cooling rains using observed changes within 12 min in soil temperature at a depth of 5 cm, together with soil thermal properties and changes in VSM. On average, the estimated rainwater temperature is generally lower than the observed ambient air temperature, wet-bulb temperature, and topsoil temperature at a depth of 5 cm, with mean differences of −5.1ºC, −3.8ºC, and −11.1ºC, respectively. The most pronounced differences are attributed to hailstorms or to hailstones melting before getting to the soil surface. Ignoring this cooling effect can introduce biases in land surface energy budget simulations.

Sibo Zhang et al.
Interactive discussion
Status: open (until 21 Jan 2019)
Status: open (until 21 Jan 2019)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Sibo Zhang et al.
Viewed  
Total article views: 210 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
179 29 2 210 9 0 2
  • HTML: 179
  • PDF: 29
  • XML: 2
  • Total: 210
  • Supplement: 9
  • BibTeX: 0
  • EndNote: 2
Views and downloads (calculated since 26 Nov 2018)
Cumulative views and downloads (calculated since 26 Nov 2018)
Viewed (geographical distribution)  
Total article views: 196 (including HTML, PDF, and XML) Thereof 195 with geography defined and 1 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 13 Dec 2018
Publications Copernicus
Special issue
Download
Short summary
In situ rain-temperature measurements are rare. Soil moisture and soil temperature observations in southern France are used to assess the cooling effects on soils of rainfall events. The rainwater temperature is estimated using observed changes of topsoil volumetric soil moisture and soil temperature in response to the rainfall event. The obtained rain temperature estimates are generally lower than the ambient air temperatures, wet-bulb temperatures, and topsoil temperatures.
In situ rain-temperature measurements are rare. Soil moisture and soil temperature observations...
Citation
Share