Forcing the Penman-Montheith Formulation with Humidity, Radiation, and Wind Speed Taken from Reanalyses, for Hydrologic Modeling

The Penman-Monteith reference evapotranspiration (ET0) formulation was forced with humidity, radiation, and wind speed (HRW) fields simulated by four reanalyses in order to simulate hydrologic processes over six mid-sized nivo-pluvial watersheds in southern Quebec, Canada. The resulting simulated hydrologic response is comparable to an empirical ET0 formulation based exclusively on air temperature. However, Penman-Montheith provides a sounder representation of the existing relations between evapotranspiration fluctuations and climate drivers. Correcting HRW fields significantly improves the hydrologic bias over the pluvial period (June to November). The latter did not translate into an increase of the hydrologic performance according to the Kling-Gupta Efficiency (KGE) metric. The suggested approach allows for the implementation of physically-based ET0 formulations where HRW observations are insufficient for the calibration and validation of hydrologic models and a potential reinforcement of the confidence affecting the projection of low flow regimes and water availability.

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Reference Evapotranspiration (ETo) Methods Implemented as ArcMap Models with Remote-Sensed and Ground-Based Inputs, Examined along with MODIS ET, for Peloponnese, Greece

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi10060390 ◽

2021 ◽

Vol 10 (6) ◽

pp. 390

Author(s):

Stavroula Dimitriadou ◽

Konstantinos G. Nikolakopoulos

Keyword(s):

Climate Change ◽

Wind Speed ◽

Water Availability ◽

Physical Meaning ◽

Reference Evapotranspiration ◽

Meteorological Data ◽

Mediterranean Area ◽

National Observatory ◽

Evaporative Demand ◽

Time Saving

The present study develops ArcMap models to implement the following three methods: FAO-56 Penman–Monteith (FAO PM), Hargreaves–Samani (HS) and Hansen, with the former used as a reference. Moreover, three models implementing statistical indices (RMSD, MB, NMB) are also created. The purpose is threefold, as follows: to investigate the variability in the daily mean reference evapotranspiration (ETo) for the Decembers and Augusts during 2016–2019, over Peloponnese, Greece. Furthermore, to investigate the agreement between the methods’ ETo estimates, and examine the former along with MODIS ET (daily) averaged products. The study area is a complex Mediterranean area. Meteorological data from sixty-two stations under the National Observatory of Athens (NOA), and MODIS Terra LST products, have been employed. FAO PM is found sensitive to wind speed and depicts interactions among climate parameters (T, evaporative demand and water availability) in the frame of climate change. The years 2016–2019 are four of the warmest since the preindustrial era. Hargreaves–Samani’s estimations for the Decembers of 2016–2019 were almost identical to MODIS ET, despite their different physical meaning. However, for the Augusts there are considerable discrepancies between the methods’ and MODIS’s estimates, attributed to the higher evaporative demand in the summertime. The GIS models are accurate, reliable, time-saving, and adjustable to any study area.

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Sensitivity of Conceptual and Physically Based Hydrologic Models to Temporal and Spatial Rainfall Sampling

Journal of Hydrologic Engineering ◽

10.1061/(asce)1084-0699(2009)14:7(711) ◽

2009 ◽

Vol 14 (7) ◽

pp. 711-720 ◽

Cited By ~ 17

Author(s):

E. A. Meselhe ◽

E. H. Habib ◽

O. C. Oche ◽

S. Gautam

Keyword(s):

Hydrologic Models ◽

Physically Based ◽

Temporal And Spatial

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Empirical Equations to Estimate Evapotranspiration in Mosul City

Tikrit Journal of Engineering Sciences ◽

10.25130/tjes.27.4.10 ◽

2020 ◽

Vol 27 (4) ◽

pp. 98-102

Author(s):

Haqqi Yasin ◽

Luma Abdullah

Keyword(s):

Wind Speed ◽

Relative Humidity ◽

Air Temperature ◽

Reference Evapotranspiration ◽

Sunshine Duration ◽

Food And Agriculture ◽

Food And Agriculture Organization ◽

Daily Data ◽

Daily Sunshine ◽

Measured Wind Speed

Average daily data of solar radiation, relative humidity, wind speed and air temperature from 1980 to 2008 are used to estimate the daily reference evapotranspiration in the Mosul City, North of Iraq. ETo calculator software with the Penman Monteith method standardized by the Food and Agriculture Organization is used for calculations. Further, a nonlinear regression approach using SPSS Statistics is utilized to drive the daily reference evapotranspiration relationships in which ETo is function to one or more of the average daily air temperature, actual daily sunshine duration, measured wind speed at 2m height and relative humidity

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Performance of different methods for reference evapotranspiration estimation in Jaíba, Brazil

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v22n2p83-89 ◽

2018 ◽

Vol 22 (2) ◽

pp. 83-89 ◽

Cited By ~ 1

Author(s):

Gustavo H. da Silva ◽

Santos H. B. Dias ◽

Lucas B. Ferreira ◽

Jannaylton É. O. Santos ◽

Fernando F. da Cunha

Keyword(s):

Wind Speed ◽

Solar Radiation ◽

Standard Method ◽

Reference Evapotranspiration ◽

Meteorological Data ◽

Air Humidity ◽

Method Performance ◽

Relative Air Humidity ◽

Evapotranspiration Estimation ◽

Missing Variables

ABSTRACT FAO Penman-Monteith (FO-PM) is considered the standard method for the estimation of reference evapotranspiration (ET0) but requires various meteorological data, which are often not available. The objective of this work was to evaluate the performance of the FAO-PM method with limited meteorological data and other methods as alternatives to estimate ET0 in Jaíba-MG. The study used daily meteorological data from 2007 to 2016 of the National Institute of Meteorology’s station. Daily ET0 values were randomized, and 70% of these were used to determine the calibration parameters of the ET0 for the equations of each method under study. The remaining data were used to test the calibration against the standard method. Performance evaluation was based on Willmott’s index of agreement, confidence coefficient and root-mean-square error. When one meteorological variable was missing, either solar radiation, relative air humidity or wind speed, or in the simultaneous absence of wind speed and relative air humidity, the FAO-PM method showed the best performances and, therefore, was recommended for Jaíba. The FAO-PM method with two missing variables, one of them being solar radiation, showed intermediate performance. Methods that used only air temperature data are not recommended for the region.

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Multiscale coherence analysis of reference evapotranspiration of north-western Iran using wavelet transform

Journal of Water and Climate Change ◽

10.2166/wcc.2021.379 ◽

2021 ◽

Author(s):

V. Sreedevi ◽

S. Adarsh ◽

Vahid Nourani

Keyword(s):

Wind Speed ◽

Reference Evapotranspiration ◽

Local Scale ◽

Wavelet Coherence ◽

Coherence Analysis ◽

Drastic Reduction ◽

North West ◽

Mean Temperature ◽

North Western ◽

Multiple Wavelet Coherence

Abstract This study applies different wavelet coherence formulations for investigating the multiscale associations of reference Evapotranspiration (ET0) of Tabriz and Urmia stations in North West Iran with five climatic variables, mean temperature (T), pressure (P), relative humidity (RH), wind speed (U) and Solar Radiation (SR). The relationships between different variables are quantified using the Average Wavelet Coherence (AWC) and the Percentage of Significant Coherence (PoSC). The Bivariate Wavelet Coherence (BWC) analysis showed that mean temperature (AWC = 0.73, PoSC = 59.18%) and wind speed (AWC = 0.63, PoSC = 49.55%) are the dominant predictors at Tabriz and Urmia stations. On considering the Multiple Wavelet Coherence (MWC) analysis, it is noticed that among the two-factor combinations, the T-P and P-RH combinations resulted in the highest coherence values for Tabriz and Urmia stations. T-U-SR combination produced the highest multiple wavelet coherence values among the three-factor cases for both the stations. The Partial Wavelet Coherence (PWC) analysis indicated a drastic reduction in coherence from the values of respective BWC analysis, indicating a strong interrelationship between different variables and ET0. The interrelationship between meteorological variables and ET0 is more apparent at Tabriz, while it is controlled more by the local-scale meteorology at Urmia.

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Numerical simulations of the impact of climate variability and change on semiarid watershed response in central New Mexico

Hydrology and Earth System Sciences Discussions ◽

10.5194/hessd-6-319-2009 ◽

2009 ◽

Vol 6 (1) ◽

pp. 319-371

Author(s):

E. R. Vivoni ◽

C. A. Aragón ◽

L. Malczynski ◽

V. C. Tidwell

Keyword(s):

Climate Change ◽

New Mexico ◽

Summer Precipitation ◽

Climate Change Scenarios ◽

Hydrologic Response ◽

Watershed Model ◽

Precipitation Regime ◽

Hydrologic Processes ◽

Precipitation Characteristics ◽

The Impact

Abstract. Hydrologic processes in the semiarid regions of the southwest United States are considered to be highly susceptible to variations in temperature and precipitation characteristics due to the effects of climate change. Relatively little is known on the potential impacts of climate change on the basin hydrologic response, namely streamflow, evapotranspiration and recharge, in the region. In this study, we present the development and application of a continuous, semi-distributed watershed model for climate change studies in semiarid basins of the southwest US. Our objective is to capture hydrologic processes in large watersheds, while accounting for the spatial and temporal variations of climate forcing and basin properties in a simple fashion. We apply the model to the Río Salado basin in central New Mexico since it exhibits both a winter and summer precipitation regime and has a historical streamflow record for model testing purposes. Subsequently, we utilize a sequence of climate change scenarios that capture observed trends for winter and summer precipitation, as well as their interaction with higher temperatures, to perform long-term ensemble simulations of the basin hydrologic response. Results of the modeling exercise indicate that precipitation uncertainty is amplified in the hydrologic response, in particular for processes that depend on a soil saturation threshold. We obtained substantially different hydrologic sensitivities for winter and summer precipitation ensembles, indicating a greater sensitivity to more intense summer storms as compared to more frequent winter events. In addition, the impact of changes in precipitation characteristics overwhelmed the effects of increased temperature in the study basin. Nevertheless, combined trends in precipitation and temperature yield a more sensitive hydrologic response throughout the year.

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Development of a large-sample watershed-scale hydrometeorological data set for the contiguous USA: data set characteristics and assessment of regional variability in hydrologic model performance

Hydrology and Earth System Sciences ◽

10.5194/hess-19-209-2015 ◽

2015 ◽

Vol 19 (1) ◽

pp. 209-223 ◽

Cited By ~ 116

Author(s):

A. J. Newman ◽

M. P. Clark ◽

K. Sampson ◽

A. Wood ◽

L. E. Hay ◽

...

Keyword(s):

United States ◽

Seasonal Cycle ◽

Model Performance ◽

The United States ◽

Hydrologic Model ◽

Low Flow ◽

Reference Level ◽

Hydrologic Response ◽

Data Set ◽

Wide Range

Abstract. We present a community data set of daily forcing and hydrologic response data for 671 small- to medium-sized basins across the contiguous United States (median basin size of 336 km2) that spans a very wide range of hydroclimatic conditions. Area-averaged forcing data for the period 1980–2010 was generated for three basin spatial configurations – basin mean, hydrologic response units (HRUs) and elevation bands – by mapping daily, gridded meteorological data sets to the subbasin (Daymet) and basin polygons (Daymet, Maurer and NLDAS). Daily streamflow data was compiled from the United States Geological Survey National Water Information System. The focus of this paper is to (1) present the data set for community use and (2) provide a model performance benchmark using the coupled Snow-17 snow model and the Sacramento Soil Moisture Accounting Model, calibrated using the shuffled complex evolution global optimization routine. After optimization minimizing daily root mean squared error, 90% of the basins have Nash–Sutcliffe efficiency scores ≥0.55 for the calibration period and 34% ≥ 0.8. This benchmark provides a reference level of hydrologic model performance for a commonly used model and calibration system, and highlights some regional variations in model performance. For example, basins with a more pronounced seasonal cycle generally have a negative low flow bias, while basins with a smaller seasonal cycle have a positive low flow bias. Finally, we find that data points with extreme error (defined as individual days with a high fraction of total error) are more common in arid basins with limited snow and, for a given aridity, fewer extreme error days are present as the basin snow water equivalent increases.

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