جستجوی مقالات مرتبط با کلیدواژه "fao-penman-monteith" در نشریات گروه "هواشناسی"

One of the ways to reduce the water crisis in agriculture due to its low consumption efficiency and overuse of available resources is water management to meet the water needs of crops in arid areas where water resources are limited, and estimating the water needs of plants is essential. In this study, FAO Penman Montith method was used to estimate the evapotranspiration potential of Northeast Iran, and ArcGIS software was used to zonation of evapotranspiration. The data required for this study were collected from 15 meteorological stations affiliated to the Meteorological Organization located in Khorasan Province (Razavi, jonubi, Shomali). These data are for the years 1999 to 2019 and include daily maximum and minimum values of air temperature, relative humidity, sunshine hours and wind speed. Days with incomplete data were excluded from analysis in this study. The results of this study showed that the rate of evapotranspiration on average days of the year varies from 0 to 6.9 mm per day and the highest evapotranspiration in July (134.4) mm per month and the lowest evapotranspiration in January (18.7) mm has occurred in the month. Potential evapotranspiration zoning in ArcGIS software environment showed that the highest evapotranspiration was in the southwest of the study area (Tabas) and the lowest was in the northeast of the study area (Quchan and Bojnourd).

Evapotranspiration is an important factor of hydrological cycle that must be estimated in irrigation and drainage projects. Studies have shown that in the absence of lysimeter, FAO Penman-Monteith method provide acceptable estimate of evapotranspiration values, but this method requires a lot of meteorological parameters. Therefore other hydrological evapotranspiration methods that needs few parameters should be evaluate for each region. In this study reference crop evapotranspiration calculated by Ref-ET software for Sepidan, Fars, by using Sepidan synoptic stations meteorological data during years 2004 to 2015. The results of methods compared with FAO Penman-Monteith standard method. The efficiency of all methods was evaluated using Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) statistic parameters. The results showed that Methods based on Penman-Monteith (ASCE st PM, ASCE PM rs, ASCE PM), respectively, with the RMSE of about 0.03, 0.079, 0.079 and with the MAE of about, 0.021, 0.068, 0.069 appropriate methods for estimating reference evapotranspiration are considered. FAO 24Rd Pan and FAO Pan Methods, respectively, with the RMSE of about 1.426, 2.338 and with the MAE of about 1.186, 2.072 has the least compliance with the Penman-Monteith FAO method. So in situation of less data for FAO Penman-Monteith method in Sepidan, it is possible to use of other methods that needs few hydrological parameters.