Responses of reference evapotranspiration to changes in atmospheric humidity and air temperature in Spain

Abstract

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 44:27-40 (2010) - DOI: https://doi.org/10.3354/cr00919 Responses of reference evapotranspiration to changes in atmospheric humidity and air temperature in Spain R. Moratiel1,2,*, J. M. Durán1,2, R. L. Snyder3 1Universidad Politécnica de Madrid, Departamento de Producción Vegetal: Fitotecnia, 28040 Madrid, Spain 2CEIGRAM, Research Centre for the Management of Agricultural and Environmental Risks, 28040 Madrid, Spain 3University of California, Davis, Department of Land, Air and Water Resources, Davis, California 95616, USA *Email: ruben.moratiel@upm.es ABSTRACT: We studied the sensitivity of reference evapotranspiration (ETo) to global warming in Spain at the end of the 21st century. The FAO-56 Penman-Monteith equation was used to estimate ETo, and we examined the sensitivity of the latter to changes in temperature and relative humidity. Changes in stomatal resistance in response to increased CO2 concentration were not evaluated, nor were the changes in wind velocity and solar radiation. Different scenarios were used for estimation of future ETo in different river basins as a consequence of trends in the maximum and minimum temperatures and maximum and minimum humidities during the period 1973–2002, as observed from 38 meteorological stations. The temperature increases ranged between 0.3 and 0.7°C decade–1, and the relative humidities fluctuated between 0.1 and –3.7% decade–1. Four scenarios were simulated that considered the variations in linear tendency of the maximum and minimum temperatures and maximum and minimum relative humidities. The trends of the 4 scenarios were incorporated with the data from 338 agrometeorological stations to estimate future ETo. In all cases, there was an annual increase in ETo of 11, 21, 36 and 7% above the annual ETo (1196 mm) for Scenarios 0, 1, 2 and 3, respectively. The river basin most affected by these changes was the Ebro River valley. The most affected months were May, June, July and August, while the least affected months were November, December and January. KEY WORDS: Evapotranspiration · Climate change · Temperature · Relative humidity · Spain Full text in pdf format PreviousNextCite this article as: Moratiel R, Durán JM, Snyder RL (2010) Responses of reference evapotranspiration to changes in atmospheric humidity and air temperature in Spain. Clim Res 44:27-40. https://doi.org/10.3354/cr00919 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 44, No. 1. Online publication date: October 28, 2010 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2010 Inter-Research.