Journal
AGRICULTURAL WATER MANAGEMENT
Volume 245, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.agwat.2020.106531
Keywords
Evapotranspiration; Aridity; Boundary layer profiles; Blending height; Conditioning; Reference evapotranspiration; Surface energy balance; Weather data
Categories
Funding
- Idaho Agricultural Experiment Station [IDA0146]
- Idaho Department of Water Resources [CON00907]
- USGS Landsat Science Team [USGS G12PC00068]
- Nebraska Agricultural Experiment Station [NEB-38-077]
- State of Nevada
- Desert Research Institute
Ask authors/readers for more resources
Meteorological data collected in dry regions may exhibit biases due to aridity effects, which can impact reference ET calculations. This study developed a weather data conditioning process to adjust for these biases. Results showed that reference ETo may be overstated in certain regions.
Meteorological data are often collected in dry, desert regions where the local environments exhibit effects of aridity caused by the lack of evapotranspiration (ET). In contrast, the standard reference ET (ETo) calculations of FAO56 and ASCE assume that the surfaces underlying collected weather data are well-watered so that near-surface meteorological measurements reflect the cooling and humidifying effects of an evaporating surface. In this study, we develop a weather data conditioning process and algorithms to adjust for biases in meteorological data that exhibit aridity effects. The conditioning process is intended to adjust the weather data to better exhibit characteristics of data collected over a well-watered vegetated surface prior to use of the data to estimate reference ET. The procedure involves the extrapolation of air temperature, vapor pressure, and wind speed profiles to and from a regional blending height using standard surface energy balance equations and flux-profile relationships and employing ET estimated for the ambient, dry conditions of an arid weather station and reference ET that should co-exist with weather measurements used to calculation reference ET. Example applications are given with 24-hour weather data and hourly weather data in Idaho and Nevada. Results indicate that reference ETo can be overstated by as much as 25% in southern Idaho and 8% in eastern Nevada. The methodology is intended to be transferrable to other regions and climates and is self-aware of the need for conditioning of weather data according to differences in ambient ET and the reference ET estimates.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available