Electronic Journal of Polish Agricultural Universities (EJPAU) founded by all Polish Agriculture Universities presents original papers and review articles relevant to all aspects of agricultural sciences. It is target for persons working both in science and industry,regulatory agencies or teaching in agricultural sector. Covered by IFIS Publishing (Food Science and Technology Abstracts), ELSEVIER Science - Food Science and Technology Program, CAS USA (Chemical Abstracts), CABI Publishing UK and ALPSP (Association of Learned and Professional Society Publisher - full membership). Presented in the Master List of Thomson ISI.
2013
Volume 16
Issue 3
Topic:
Agronomy
ELECTRONIC
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
Karvonen J. 2013. EFFECT OF SNOW LAYER ON GROUND SURFACE TEMPERATURE IN COOL WINE GROWING REGIONS, EJPAU 16(3), #10.
Available Online: http://www.ejpau.media.pl/volume16/issue3/abs-10.html

EFFECT OF SNOW LAYER ON GROUND SURFACE TEMPERATURE IN COOL WINE GROWING REGIONS

Juha Karvonen
Department of Agricultural Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Finland

 

ABSTRACT

his study set out to find how snow affects ground surface temperatures and to evaluate what kind of influence this has on grapevine growing. Temperatures were measured with digital maximum-minimum thermometers that stored the readings. The research shows that in winters when there is little snow, the correlation between ground surface temperature and air temperature is strong ( = 0.93–0.99) because there is not enough snow to act as an insulator. In winters when there is plenty of snow, no such correlation exists ( = 0.0001–0.3) because the thick layer of snow acts as an insulator and controls changes in ground surface temperature and air temperature. In very cold weather (-25.0 to -27.4°C), a thick layer of snow (61–67 cm) kept the ground surface minimum temperature at -0.5 to -1.3°C. A thin snow layer (18–32 cm) did not stop the ground surface temperature from falling; the ground surface temperature fell to -10.8°C when air temperature stayed within the same temperature range. In north Europe, central Europe and other cool wine-growing regions, a snowy winter prevents the ground from freezing and thus protects the vines from very cold temperatures.

Key words: snow and viticulture, ground temperature, snow insulation, freezing, Nordic viticulture.


Juha Karvonen
Department of Agricultural Sciences, Faculty of Agriculture and Forestry, University of Helsinki, Finland
P.O.Box 28, 00014 Helsinki
Finland
email: j.i.karvonen@helsinki.fi

Responses to this article, comments are invited and should be submitted within three months of the publication of the article. If accepted for publication, they will be published in the chapter headed 'Discussions' and hyperlinked to the article.