Air temperatures in a power line corridor over 10years following afforestation with Eucalyptus globulus

• Published in: Theoretical and applied climatology 2011-03, Vol.103 (3-4), p.281-290
• Main Authors: Rodriguez-Suarez, JA, Soto, B, Perez, R, Diaz-Fierros, F
• Format: Article
• Language: English
• ISSN: 0177-798X; 1434-4483
• DOI: 10.1007/s00704-010-0300-0

Over the 10years following the planting of Eucalyptus globulus on an area of 320ha in 1998, air temperature was measured in the middle of a power line corridor and compared with temperatures recorded at meteorological stations located 11.2 and 35.7km away. At these reference stations, the annual means of both daily minimum and daily maximum temperature remained approximately constant. In the power line corridor, annual mean daily minimum temperature also remained approximately constant, but annual mean daily maximum temperature fell by about 3.6 degree C; in particular, between years 4 and 7 the cooling rate was on average about 0.7 degree C per year. The resulting sigmoid time course of annual mean daily temperature range may partly reflect the evolution of evapotranspiration from the plantation, but seems to be mainly attributable to the shading of the power line corridor by the growing trees, being closely correlated with solar irradiance at the center of the corridor as estimated from tree growth data using sun charts and standard formulae for clear-sky solar irradiance.