Download enso influence on soil water balance and temperature in pampean

ENSO INFLUENCE ON SOIL WATER BALANCE AND TEMPERATURE IN
PAMPEAN FLATLANDS (ARGENTINA) WITH SPECIAL ANALYSIS TO
SAN PEDRO AREA*
SCARPATI, O. E.(1, 2), J. A FORTE LAY (1), M. E. FERNANDEZ LONG (3), and A. D.
CAPRIOLO (1)
(1)
National Council of Scientific and Technical Research [email protected]
(2)
Geography Department, Humanities and Education Sciences Faculty, La Plata
National University
(3)
Agronomy Faculty, Buenos Aires University (UBA)
ABSTRACT
In the present paper, air temperature and agro climatic characteristics in
pampean flatlands are analyzed with special emphasis to San Pedro area (Buenos
Aires province). Soil water balance, autumn surplus, maximum and minimum
temperatures were studied with their relationship to ENSO.
The values of daily soil water storages were calculated for the period 1967-2005
by soil water balance according to Thornthwaite and Mather method using the daily
precipitation and daily normal potential evapotranspiration calculated by the PenmanMonteith formula.
ENSO events were separated according to El Niño or warm phase and La Niña
or cold phase, with the remaining cases being Neutral condition.
The scheme used for determining the ENSO phases was following the Wolter
classification by employing terciles of the ranked MEI values. So during the period
1967-2005, there are 14 cases of El Niño, 11 of La Niña and the rest 14 are Neutral.
The paper allows a visualisation of ENSO influence over summer soil water storage
and autumn soil water surplus.
It can be said that El Niño years contribute with higher soil water storage, higher
summer and autumn soil water surplus and colder maximum temperature than La Niña
years.
Trabajo publicado en: “Environmental change and rational water use”. J.A.A. Jones
and O. E. Scarpati (Eds). ISBN 978-987-9260-46-3. 458 pp. Session 1. 169- 183
*