AN OPERATIONAL WATER AND ENERGY BALANCE ALGORITHM FOR PUERTO RICO Eric. W. Harmsen Agricultural and Biosystems Engineering Department, University of Puerto Rico Mayaguez Campus DÉCIMA REUNIÓN NACIONAL DE PERCEPCIÓN REMOTA Y SIG DE PUERTO RICO 7 DE SEPTIEMBRE DE 2012 http://pragwater.com USDA Hatch
2009 OBJECTIVE Develop an algorithm for estimating daily, high resolution (1-km), crop reference evapotranspiration (ET o ) over Puerto Rico. ET a = K c ET o
2010 OBJECTIVE Introduce several new water resource-related remote sensing products for Puerto Rico, Haiti and the Dominican Republic.
OBJECTIVES To operationalize GOES-PRWEB o Automate the calculation process and publish the daily, monthly and annual averages/totals on a website. Introduce several additional water resourcerelated remote sensing products for Puerto Rico. Validate the solar radiation product for PR
Technical Approach
Algorithm Flow Chart SM 2 = Precip ET a RO DP SM 1 Obtain Solar Radiation, wind speed, rainfall, etc,. for yesterday Estimate Components of the Surface Water Budget Expand the components of the Surface Energy Budget Estimate Actual Evapotranspiration (ET a ) Solve Surface Energy Budget implicitly in terms of the Effective Surface Temperature Estimate the components of the surface energy budget R net + λe + H + G = 0
Remotely Sensed Solar Radiation Solar radiation was obtained using the Modified Gautier and Diak method (Gautier et al., 1980; Diak and Gautier, 1983). Data were obtained from the GOES-East satellite. Geostationary platform 1 km resolution for Puerto Rico 2 km Haiti and the Dominican Republic High time resolution (30-60 minutes)
RESULTS
Operationalize GOES-PRWEB 24 hydro-climate variables are produced each day at the website: pragwater.com. Monthly and annual averages/totals are also available.
New Products: Reference Evapotranspiration Penman-Monteith Priestly Taylor Hargreaves Samani Bowen Ratio (H/λE) Aerodynamic Resistance Bulk Surface Resistance Soil Saturation
Monthly Average Bowen Ratio, Rainfall, Soil Saturation and Solar Radiation (Aug. 2012) Bowen Ratio Soil Saturation Rainfall Solar Radiation
Latent Heat Flux Estimates from CFS Model (M. Jury, 2011) and GOES-PRWEB for Haiti and DR Latent Heat Latent Heat Sensible Heat Reference Evapotranspiration (mm) Bowen Ratio Haiti Dominican Republic
Applications of GOES-PRWEB 1. Reduced rainfall and surface runoff in El Yunque in June 2012 2. Web-based irrigation scheduling tool
Low Rainfall in El Yunque during June 2012 June 2009 June 2010 June 2011 June 2012
Low Surface Runoff in El Yunque during June 2012 June 2009 June 2010 June 2011 June 2012
Web-Based Irrigation Scheduling Tool
Validation of Remotely Sensed Daily Integrated Solar Radiation Study Sites
Hourly Integrated Solar Radiation Hourly-integrated solar radiation for silicon pyranometer vs pyranometers at Guilarte, Fortuna and UPRM. R 2 UPRM = 0.9786 R 2 Fortuna=0.9738 R 2 Guilarte=0.8184
Daily Integrated Solar Radiation Daily-integrated solar radiation for silicon pyranometer vs pyranometers at Guilarte, Fortuna and UPRM. R 2 UPRM = 0.9755 R 2 Fortuna=0.9774 R 2 Guilarte=0.7202
Daily Integrated Solar Radiation Re-Calibration of Pyranometers UPRM and Fortuna Combined Data
Daily Integrated Solar Radiation Fortuna Daily-integrated Solar Radiation for 283 days in 2010. Fortuna Pyranometers vs. uncorrected data(a), Fortuna equ. (B) and Combined data equ. (C). Licor 200 Pyranometer uncorrected Fortuna Equ. Combined Data Equ.
Daily Integrated Solar Radiation UPRM Daily-integrated Solar Radiation for 226 days in 2010. UPRM Pyranometers vs. uncorrected (A), UPRM equ. (B) and Combined data equ. (C). Watchdog Silicon Pyranometer uncorrected UPRM Equ. Combined Data Equ.
Results of statistical analyses of the validation data
Results of statistical analyses of the validation data The study recommended that the uncorrected remotely sensed data produces reasonably accurate results and can be used throughout Puerto Rico
Summary and Conclusions GOES-PRWEB has been operationalized. Currently daily results are available at the website pragwater.com. Monthly and annual averages/totals of hydro-climate variables are also available. Some new hydro-climate variables have been added to the algorithm Two applications of GOES-PRWEB were presented Results of a calibration/validation study of a remotely sensed solar radiation product for Puerto Rico was conducted. The solar radiation product is the main input to the GOES-PRWEB application. The study recommended that the uncorrected data can be used throughout Puerto Rico.
Future Work Initiate calibration/validation studies for runoff, evapotranspiration, soil moisture. Improve the web interface for viewing images and downloading data. Provide archived tabular and graphical (e.g., time series) results, and statistics of these data (e.g., wet season aquifer recharge) Develop additional hydro-climate products
Acknowledgements Financial Support: USDA-Hatch (H-402) NOAA-CREST (NA17AE1625)