Monitoring evapotranspiration at landscape scale in Mexico: applying the energy balance model using remotely sensed data

Abstract. The availability of the actual water use from agricultural crops is considered as the key factor for irrigation water management, water resources planning, and water allocation. Traditionally, evapotranspiration (ET) has been estimated in the Gezira scheme by multiplying the reference evapotranspiration (ETo) by crop coefficient (kc) which is derived from the phenomenological crop stages. Recently, advanced developed energy balance models assist to estimate ET through remotely sensed data. In this study Enhanced Thematic Mapper Plus (ETM+) images were used to estimate spatial distribution of daily, monthly and seasonal ET for irrigated sorghum in the Gezira scheme, Sudan. The daily ET maps were also used to estimate kc over time and space. Results of remotely sensed based energy balance were compared with actual measurements conducted during 2004/05 season. The daily actual ET values estimated using the energy balance model during the satellite acquisition dates (28 July, 29 August, 16 October and 17 November) were 4.7, 5.5, 7.1 and 2.7 mm/day, while the average seasonal evapotranspiration for irrigated sorghum estimated to be around 596 mm. The remotely estimated kc values in the initial, crop development, mid-season and late-season stages were 0.62, 0.85, 1.15, and 0.48 respectively. On the other hand the widely used tradition kc values during the pervious mention stages are 0.55, 0.94, 1.21 and 0.65, respectively. This research shows that remotely sensed measurements can help objectively analyzed the irrigation water requirement for different field crops on daily and seasonal time step. Moreover, the remotely sensed real-time data availability provides the system managers with information that not previously available.

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Satellite-based energy balance model to estimate seasonal evapotranspiration for irrigated sorghum: a case study from the Gezira scheme, Sudan

Hydrology and Earth System Sciences ◽

10.5194/hess-12-1129-2008 ◽

2008 ◽

Vol 12 (4) ◽

pp. 1129-1139 ◽

Cited By ~ 19

Author(s):

M. A. Bashir ◽

T. Hata ◽

H. Tanakamaru ◽

A. W. Abdelhadi ◽

A. Tada

Keyword(s):

Energy Balance ◽

Water Use ◽

Remotely Sensed ◽

Balance Model ◽

Remotely Sensed Data ◽

Key Factor ◽

Moderate Resolution ◽

Moderate Resolution Imaging Spectroradiometer ◽

Crop Coefficients ◽

Consistent Information

Abstract. The availability of the actual water use from agricultural crops is considered as the key factor for irrigation water management, water resources planning, and water allocation. Traditionally, evapotranspiration (ET) has been calculated in the Gezira scheme as the point of reference with evapotranspiration (ETo) and crop coefficients (kc) being derived from actual measurements of soil-water balance. Recently developed, advanced energy balance models assisted in estimating the ET through the remotely sensed data. In this study Enhanced Thematic Mapper Plus (ETM+) and MODerate Resolution Imaging Spectroradiometer (MODIS) images were used to estimate the spatial distribution of the daily, monthly and seasonal ET for irrigated sorghum in the Gezira scheme, Sudan. The daily ET maps were also used to estimate kc over time and space. Results of the energy balance, based on being remotely sensed, were compared to actual measurements conducted during 2004/05 season. The seasonal actual ET values, obtained from the seven MODIS images for irrigated sorghum, were estimated at 579 mm. The values for remotely sensed kc, derived during the initial mid-season and late-season crop development stages, were 0.62, 0.85, 1.15, and 0.48, respectively. On the other hand, the values for the experimental kc during the pervious mention stages were 0.55, 0.94, 1.21 and 0.65, respectively. The estimated seasonal ET of the sorghum, derived by remotely sensed kc, was 674 mm. The Landsat data and the Free MODIS provided reliable, exhaustive, and consistent information on the water use, relevant for decision support in the Gezira scheme.

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Committed Warming Due to Earth’s Radiative Imbalance Using a Simple 5-Factor Energy Balance Model

SSRN Electronic Journal ◽

10.2139/ssrn.3541353 ◽

2020 ◽

Author(s):

Ronn Smith

Keyword(s):

Energy Balance ◽

Energy Balance Model ◽

Balance Model

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Response of the Energy Balance on the Margin of the Greenland Ice Sheet to Temperature Changes

Journal of Glaciology ◽

10.1017/s0022143000009461 ◽

1990 ◽

Vol 36 (123) ◽

pp. 217-221 ◽

Cited By ~ 25

Author(s):

Roger J. Braithwaite ◽

Ole B. Olesen

Keyword(s):

Heat Flux ◽

Energy Balance ◽

Air Temperature ◽

Sensible Heat Flux ◽

Ice Sheet ◽

Temperature Response ◽

Greenland Ice Sheet ◽

Energy Balance Model ◽

Balance Model ◽

Sensible Heat

AbstractDaily ice ablation on two outlet glaciers from the Greenland ice sheet, Nordbogletscher (1979–83) and Qamanârssûp sermia (1980–86), is related to air temperature by a linear regression equation. Analysis of this ablation-temperature equation with the help of a simple energy-balance model shows that sensible-heat flux has the greatest temperature response and accounts for about one-half of the temperature response of ablation. Net radiation accounts for about one-quarter of the temperature response of ablation, and latent-heat flux and errors account for the remainder. The temperature response of sensible-heat flux at QQamanârssûp sermia is greater than at Nordbogletscher mainly due to higher average wind speeds. The association of high winds with high temperatures during Föhn events further increases sensible-heat flux. The energy-balance model shows that ablation from a snow surface is only about half that from an ice surface at the same air temperature.

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