Geographic Information Sciences Commons^™

Landsat 5 Thematic Mapper Reflectance And Ndvi 27-Year Time Series Inconsistencies Due To Satellite Orbit Change, Hankui Zhang, David P. Roy

GSCE Faculty Publications

The Landsat 5 Thematic Mapper (TM) sensor provided the longest single mission terrestrial remote sensing data record but temporally sparse station keeping maneuvers meant that the Landsat 5 orbit changed over the 27 year mission life. Long-term Landsat 5 TM reflectance inconsistencies may be introduced by orbit change induced solar zenith variations combined with surface reflectance anisotropy, commonly described by the Bi-directional Reflectance Distribution Function (BRDF). This study quantifies the local overpass time and observed solar zenith angle changes for all the Landsat 5 TM images available at two latitudinally separated locations along the same north-south Landsat path (27) in …

A Note On The Temporary Misregistration Of Landsat-8 Operational Land Imager (Oli) And Sentinel-2 Multi Spectral Instrument (Msi) Imagery, James Storey, David P. Roy, Jeffrey Masek, Ferran Gascon, Michael Choate

GSCE Faculty Publications

The Landsat-8 and Sentinel-2 sensors provide multi-spectral image data with similar spectral and spatial characteristics that together provide improved temporal coverage globally. Both systems are designed to register Level 1 products to a reference image framework, however, the Landsat-8 framework, based upon the Global Land Survey images, contains residual geolocation errors leading to an expected sensor-to-sensor misregistration of 38 m (2σ). These misalignments vary geographically but should be stable for a given area. The Landsat framework will be readjusted for consistency with the Sentinel-2 Global Reference Image, with completion expected in 2018. In the interim, users can measure Landsat-to-Sentinel tie …

Characterization Of Landsat-7 To Landsat-8 Reflective Wavelength And Normalized Difference Vegetation Index Continuity, David P. Roy, V. Kovalskyy, Hankui Zhang, Eric F. Vermote, Lin Yan Dr., Sanath Sathyachandran Kumar, Alexey V. Egorov

GSCE Faculty Publications

At over 40 years, the Landsat satellites provide the longest temporal record of space-based land surface observations, and the successful 2013 launch of the Landsat-8 is continuing this legacy. Ideally, the Landsat data record should be consistent over the Landsat sensor series. The Landsat-8 Operational Land Imager (OLI) has improved calibration, signal to noise characteristics, higher 12-bit radiometric resolution, and spectrally narrower wavebands than the previous Landsat-7 Enhanced Thematic Mapper (ETM +). Reflective wavelength differences between the two Landsat sensors depend also on the surface reflectance and atmospheric state which are difficult to model comprehensively. The orbit and sensing geometries …

Canopy Height Estimation By Characterizing Waveform Lidar Geometry Based On Shape-Distance Metric, Eric Ariel L. Salas, Geoffrey M. Henebry

GSCE Faculty Publications

There have been few approaches developed for the estimation of height using waveform LiDAR data. Unlike any existing methods, we illustrate how the new Moment Distance (MD) framework can characterize the canopy height based on the geometry and return power of the LiDAR waveform without having to go through curve modeling processes. Our approach offers the possibilities of using the raw waveform data to capture vital information from the variety of complex waveform shapes in LiDAR. We assess the relationship of the MD metrics to the key waveform landmarks—such as locations of peaks, power of returns, canopy heights, and height …

A Comparison Of Tropical Rainforest Phenology Retrieved From Geostationary (Seviri) And Polar-Orbiting (Modis) Sensors Across The Congo Basin, Dong Yan, Xiaoyang Zhang, Yunyue Yu, Wei Guo

GSCE Faculty Publications

The seasonal and interannual dynamics of tropical rainforests play a critical role in the global carbon cycle and climate change. This paper retrieved and compared land surface phenology from observations acquired by the Spinning Enhanced Visible and Infrared Imager (SEVIRI) onboard geostationary satellites and the Moderate Resolution Imaging Spectroradiometer (MODIS) on polar-orbiting satellites over the Congo Basin. To achieve this,we first retrieved canopy greenness cycles (CGCs) and their transition timing from two-band enhanced vegetation index (EVI2) derived from SEVIRI and MODIS data between 2006 and 2013.We then assessed the influences of SEVIRI and MODIS data quality on the reconstruction of …

The Influences Of Drought And Land-Cover Conversion On Inter-Annual Variation Of Npp In The Three-North Shelterbelt Program Zone Of China Based On Modis Data, Dailiang Peng, Chaoyang Wu, Bing Zhang, Alfredo Huete, Xiaoyang Zhang, Rui Sun, Liping Lei, Wenjing Huang, Liangyun Liu, Xinjie Liu, Jun Li, Shezhou Luo, Bin Fang

GSCE Faculty Publications

Terrestrial ecosystems greatly contribute to carbon (C) emission reduction targets through photosynthetic C uptake.Net primary production (NPP) represents the amount of atmospheric C fixed by plants and accumulated as biomass. The Three-North Shelterbelt Program (TNSP) zone accounts for more than 40% of China’s landmass. This zone has been the scene of several large-scale ecological restoration efforts since the late 1990s, and has witnessed significant changes in climate and human activities.Assessing the relative roles of different causal factors on NPP variability in TNSP zone is very important for establishing reasonable local policies to realize the emission reduction targets for central government. …

An Automated Approach For Sub-Pixel Registration Of Landsat-8 Operational Land Imager (Oli) And Sentinel-2 Multi Spectral Instrument (Msi) Imagery, Lin Yan, David P. Roy, Hankui Zhang, Jian Li, Haiyan Huang

GSCE Faculty Publications

Moderate spatial resolution satellite data from the Landsat-8 OLI and Sentinel-2A MSI sensors together offer 10 m to 30 m multi-spectral reflective wavelength global coverage, providing the opportunity for improved combined sensor mapping and monitoring of the Earth’s surface. However, the standard geolocated Landsat-8 OLI L1T and Sentinel-2A MSI L1C data products are currently found to be misaligned. An approach for automated registration of Landsat-8 OLI L1T and Sentinel-2A MSI L1C data is presented and demonstrated using contemporaneous sensor data. The approach is computationally efficient because it implements feature point detection across four image pyramid levels to identify a sparse …

A General Method To Normalize Landsat Reflectance Data To Nadir Brdf Adjusted Reflectance, David P. Roy, Hankui Zhang, Junchang Ju, Jose Luis Gomez-Dans, Philip E. Lewis, Crystal Barker B. Schaaf, Qingsong Sun, Jian Li, Haiyan Huang, V. Kovalskyy

GSCE Faculty Publications

The Landsat satellites have been providing spectacular imagery of the Earth's surface for over 40 years. However, they acquire images at view angles ±7.5° from nadir that cause small directional effects in the surface reflectance. There are also variations with solar zenith angle over the year that can cause apparent change in reflectance even if the surface properties remain constant. When Landsat data from adjoining paths, or from long time series are used, a model of the surface anisotropy is required to adjust all Landsat observations to a uniform nadir view (primarily for visual consistency, vegetation monitoring, or detection of …

Computationally Inexpensive Landsat 8 Operational Land Imager (Oli) Pansharpening, Hankui Zhang, David P. Roy

GSCE Faculty Publications

Pansharpening algorithms fuse higher spatial resolution panchromatic with lower spatial resolution multispectral imagery to create higher spatial resolution multispectral images. The free-availability and systematic global acquisition of Landsat 8 data indicate an expected need for global coverage and so computationally efficient Landsat 8 pansharpening. This study adapts and evaluates the established, and relatively computationally inexpensive, Brovey and context adaptive Gram Schmidt component substitution (CS) pansharpening methods for application to the Landsat 8 15 m panchromatic and 30 m red, green, blue, and near-infrared bands. The intensity images used by these CS pansharpening methods are derived as a weighted linear combination …

Conterminous United States Crop Field Size Quantification From Multi-Temporal Landsat Data, Lin Yan Dr., David P. Roy

GSCE Faculty Publications

Agricultural field size is indicative of the degree of agricultural capital investment, mechanization and labor intensity, and it is ecologically important. A recently published automated computational methodology to extract agricultural crop fields from weekly 30 m Web Enabled Landsat data (WELD) time series was refined and applied to a year of Landsat 5 Thematic Mapper (TM) and Landsat 7 Enhance Thematic Mapper Plus (ETM +) acquisitions for all of the conterminous United States (CONUS). For the first time, spatially explicit CONUS field size maps and derived information are presented. A total of 4,182,777 fields were extracted with mean and median …

The Global Landsat Archive: Status, Consolidation, And Direction, Michael A. Wulder, Joanne C. White, Thomas R. Loveland, Curtis E. Woodcock, Alan S. Belward, Warren B. Cohen, Eugene A. Fosnight, Jerad Shaw, Jeffrey G. Masek, David P. Roy

GSCE Faculty Publications

New and previously unimaginable Landsat applications have been fostered by a policy change in 2008 that made analysis-ready Landsat data free and open access. Since 1972, Landsat has been collecting images of the Earth, with the early years of the program constrained by onboard satellite and ground systems, as well as limitations across the range of required computing, networking, and storage capabilities. Rather than robust on-satellite storage for transmission via high bandwidth downlink to a centralized storage and distribution facility as with Landsat-8, a network of receiving stations, one operated by the U.S. government, the other operated by a community …

Land Cover Land Use Change And Soil Organic Carbon Under Climate Variability In The Semi-Arid West African Sahel (1960-2050), Amadou M. Dieye

Electronic Theses and Dissertations

Land Cover Land Use (LCLU) change affects land surface processes recognized to influence climate change at local, national and global levels. Soil organic carbon is a key component for the functioning of agro-ecosystems and has a direct effect on the physical, chemical and biological characteristics of the soil. The capacity to model and project LCLU change is of considerable interest for mitigation and adaptation measures in response to climate change. A combination of remote sensing analyses, qualitative social survey techniques, and biogeochemical modeling was used to study the relationships between climate change, LCLU change and soil organic carbon in the …

Simulating The Impacts Of Land-Use Land-Cover Changes On Cropland Carbon Fluxes In The Midwest Of The United States, Zhengpeng Li

Electronic Theses and Dissertations

Understanding the major drivers of the cropland carbon fluxes is important for carbon management and greenhouse gas mitigation in agriculture. Past studies found that agricultural land-use and land-cover (LULC) changes, such as changes in cropland production technologies, tillage practices, and planted crop species, could have large impacts on carbon fluxes. However, the impacts remain highly uncertain at regional to global scales. Satellite remote sensing is commonly used to create products with geospatial information on LULC changes. This geospatial information can be integrated into biogeochemical models to simulate the spatial and temporal patterns of carbon fluxes. We used the General Ensemble …

Monitoring Global Forest Land-Use And Change, Erik J. Lindquist

Electronic Theses and Dissertations

Earth’s forests contain nearly three-fourths of the World’s floral and faunal diversity, function as a large carbon sink capable of mitigating the effects of global climate change, affect local and regional physical and chemical cycles and provide wood and non-wood products. However, humans are now capable of modifying their environment in ways more impactful and at rates faster than at any other time in history. Consistent and comparable estimates of global forest land-use and change are critical for monitoring human impacts on the Earth system. International treaties and reporting requirements aimed at safeguarding the delivery of forest-related ecosystem services depend …

Evapotranspiration In The Nile Basin: Identifying Dynamics, Trends, And Drivers 2002-2011, H. Alemu, A. T. Kaptué, G. B. Senay, M. C. Wimberly, Geoffrey Henebry

Natural Resource Management Faculty Publications

Analysis of the relationship between evapotranspiration (ET) and its natural and anthropogenic drivers is critical in water-limited basins such as the Nile. The spatiotemporal relationships of ET with rainfall and vegetation dynamics in the Nile Basin during 2002–2011 were analyzed using satellite-derived data. Non-parametric statistics were used to quantify ET-rainfall interactions and trends across land cover types and subbasins. We found that 65% of the study area (2.5 million km2) showed significant (p < 0.05) positive correlations between monthly ET and rainfall, whereas 7% showed significant negative correlations. As expected, positive ET-rainfall correlations were observed over natural vegetation, mixed croplands/natural vegetation, and croplands, with a few subbasin-specific exceptions. In particular, irrigated croplands, wetlands and some forests exhibited negative correlations. Trend tests revealed spatial clusters of statistically significant trends in ET (6% of study area was negative; 12% positive), vegetation greenness (24% negative; 12% positive) and rainfall (11% negative; 1% positive) during 2002–2011. The Nile Delta, Ethiopian highlands and central Uganda regions showed decline in ET while central parts of Sudan, South Sudan, southwestern Ethiopia and northeastern Uganda showed increases. Except for a decline in ET in central Uganda, the detected changes in ET (both positive and negative) were not associated with corresponding changes in rainfall. Detected declines in ET in the Nile delta and Ethiopian highlands were found to be attributable to anthropogenic land degradation, while the ET decline in central Uganda is likely caused by rainfall reduction.

Image Interpretation-Guided Supervised Classification Using Nested Segmentation, A. V. Egorov, M. C. Hanson, David P. Roy, A. Kommareddy, P. V. Patapov

GSCE Faculty Publications

We present a new binary (two-class) supervised non-parametric classification approach that is based on iterative partitioning of multidimensional feature space into variably-sized and nested hyper-cubes (partitions). The proposed method contains elements of active learning and includes classifier to analyst queries. The spectral transition zone between two thematic classes (i.e., where training labels of different classes overlap in feature space) is targeted through iterative training derivation. Three partition categories are defined: pure, indivisible and unlabeled. Pure partitions contain training labels from only one class, indivisible partitions contain training data from different classes, and unlabeled partitions do not contain training …

A Contemporary Decennial Examination Of Changing Agricultural Field Sizes Using Landsat Time Series Data, Emma V. White, David P. Roy

GSCE Faculty Publications

Field size distributions and their changes have not been studied over large areas as field size change datasets are not available. This study quantifies agricultural field size changes in a consistent manner using Landsat satellite data that also provide geographic context for the observed decadal scale changes. Growing season cloud-free Landsat 30 m resolution images acquired from 9 to 25 years apart were used to extract field object classifications at seven sites located by examination of a global agricultural yield map, agricultural production statistics, literature review, and analysis of the imagery in the US Landsat archive. High spatial resolution data …

Spatial And Seasonal Responses Of Precipitation In The Ganges And Brahmaputra River Basins To Enso And Indian Ocean Dipole Modes: Implications For Flooding And Drought, M. S. Pervez, G. M. Henebry

Natural Resource Management Faculty Publications

We evaluated the spatial and seasonal responses of precipitation in the Ganges and Brahmaputra basins as modulated by the El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) modes using Global Precipitation Climatology Centre (GPCC) full data reanalysis of monthly global land-surface precipitation data from 1901 to 2010 with a spatial resolution of 0.5° × 0.5°. The GPCC monthly total precipitation climatology targeting the period 1951–2000 was used to compute gridded monthly anomalies for the entire time period. The gridded monthly anomalies were averaged for the years influenced by combinations of climate modes. Occurrences of El Niño alone significantly …

Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton

GSCE Faculty Publications

Satellite remote sensing estimates of gross primary production (GPP) have routinely been made using spectral vegetation indices (VIs) over the past two decades. The Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), the green band Wide Dynamic Range Vegetation Index (WDRVI_green), and the green band Chlorophyll Index (CI_green) have been employed to estimate GPP under the assumption that GPP is proportional to the product of VI and photosynthetically active radiation (PAR) (where VI is one of four VIs: NDVI, EVI, WDRVI_green, or CI_green). However, the empirical regressions between VI*PAR and …

Triennial Report: 2012-2014, Geospatial Sciences Center Of Excellence

GSCE Triennial Reports

Triennial Report Purpose [Page] 3

Geographical Information Science Center of Excellence [Page] 5

SDSU Faculty [Page] 6

EROS Faculty [Page] 13

Research Professors [Page] 19

Postdoctoral Fellows [Page] 24

GSE Ph.D Program [Page] 36

Ph.D. Fellowships [Page] 37

Ph.D. Students [Page] 38

Recent Ph.D. Graduates [Page] 46

Masters Students [Page] 56

Previous Ph.D. Students [Page] 58

Center Scholars Program [Page] 59

Research Staff [Page] 60

Administrative and Information Technology Staff [Page] 62

Computer Resources [Page] 66

Research Funding [Page] 67

Glancing Back, Looking Forward [Page] 68

Appendix I Alumni Faculty and Staff

Appendix II Cool Faculty Research and Locations

Appendix …

Impacts Of Urban Areas On Vegetation Development Along Rural-Urban Gradients In The Upper Midwest: 2003-2012, Cole Krehbiel

Electronic Theses and Dissertations

Between one-third and one-half of Earth’s land surface has been directly altered by humans, with the remainder comprised of “human-dominated ecosystems” (Vitousek et al. 2008). Earth’s population has surpassed seven billion, projected to increase by 2.5 billion by 2050 in urban areas alone (United Nations 2014). The rapid urbanization of our planet drives global environmental changes in hydrosystems, biodiversity, biogeochemical cycles, land use and land cover, and climate (Grimm et al. 2008). Urban areas alter local atmospheric conditions by modifying surface albedo and consequently evapotranspiration, releasing energy through anthropogenic heat sources, and increasing atmospheric aerosols, leading to increased temperatures in …

Land Surface Anomalies Preceding The 2010 Russian Heat Wave And A Link To The North Atlantic Oscillation, C. K. Wright, K. M. De Beurs, G. M. Henebry

Natural Resource Management Faculty Publications

The Eurasian wheat belt (EWB) spans a region across Eastern Ukraine, Southern Russia, and Northern Kazakhstan; accounting for nearly 15% of global wheat production. We assessed land surface conditions across the EWB during the early growing season (April–May–June; AMJ) leading up to the 2010 Russian heat wave, and over a longer-term period from 2000 to 2010. A substantial reduction in early season values of the normalized difference vegetation index occurred prior to the Russian heat wave, continuing a decadal decline in early season primary production in the region. In 2010, an anomalously cold winter followed by an abrupt shift to …

Improved Time Series Land Cover Classification By Missing-Observation-Adaptive Nonlinear Dimensionality Reduction, David P. Roy, L. Yan

GSCE Faculty Publications

Dimensionality reduction (DR) is a widely used technique to address the curse of dimensionality when high-dimensional remotely sensed data, such as multi-temporal or hyperspectral imagery, are analyzed. Nonlinear DR algorithms, also referred to as manifold learning algorithms, have been successfully applied to hyperspectral data and provide improved performance compared with linear DR algorithms. However, DR algorithms cannot handle missing data that are common in multi-temporal imagery. In this paper, the Laplacian Eigenmaps (LE) nonlinear DR algorithm was refined for application to multi-temporal satellite data with large proportions of missing data. Refined LE algorithms were applied to 52-week Landsat time series …

Sensitivity Of Mesoscale Modeling Of Smoke Direct Radiative Effect To The Emission Inventory: A Case Study In Northern Sub-Saharan African Region, Feng Zhang, Jun Wang, Charles Ichoku, Edward J. Hyer, Zhifeng Yang, Cui Ge, Shenjian Su, Xiaoyang Zhang, Shobha Kondragunta, Christine Wiedinmyer, Johannes W. Kaiser, Arlindo Da Silva

GSCE Faculty Publications

An ensemble approach is used to examine the sensitivity of smoke loading and smoke direct radiative effect in the atmosphere to uncertainties in smoke emission estimates. Seven different fire emission inventories are applied independently to WRF-Chem model (v3.5) with the same model configuration (excluding dust and other emission sources) over the northern sub-Saharan African (NSSA) biomass-burning region. Results for November and February 2010 are analyzed, respectively representing the start and end of the biomass burning season in the study region. For February 2010, estimates of total smoke emission vary by a factor of 12, but only differences by factors of …

Interannual Variation In Biomass Burning And Fire Seasonality Derived From Geostationary Satellite Data Across The Contiguous United States From 1995 To 2011, Xiaoyang Zhang, Shobha Kondragunta, David Roy

GSCE Faculty Publications

Wildfires exhibit a strong seasonality that is driven by climatic factors and human activities. Although the fire seasonality is commonly determined using burned area and fire frequency, it could also be quantified using biomass consumption estimates that directly represent biomass loss (a combination of the area burned and the fuel loading). Therefore, in this study a data set of long-term biomass consumed was derived from geostationary satellite data to explore the interannual variation in the fire seasonality and the possible impacts of climate change and land management practices across the Contiguous United States (CONUS). Specifically, daily biomass consumed data were …

Landsat-8: Science And Product Vision For Terrestrial Global Change Research, David P. Roy, M. A. Wulder, T. R. Loveland, C. E. Woodcock, R. G. Allen, M. C. Anderson, D. Helder, J. R. Irons, D. M. Johnson, R. Kennedy, T. A. Scambos, C. B. Schaaf, J. R. Schott, Y. Sheng, E. F. Vermote, A. S. Belward, R. Bindchadler, W. B. Cohen, F. Gao, J. D. Hipple, P. Hostert, J. Huntington, C. O. Justice, A. Kilic, V Kovalskyy, Z. P. Lee, L. Lymburner, J. G. Masek, J. Mccorkel, Y. Shuai, R. Trezza, J. Vogelmann, R. H. Wynne, Z. Zhu

GSCE Faculty Publications

Landsat 8, a NASA and USGS collaboration, acquires global moderate-resolution measurements of the Earth's terrestrial and polar regions in the visible, near-infrared, short wave, and thermal infrared. Landsat 8 extends the remarkable 40 year Landsat record and has enhanced capabilities including new spectral bands in the blue and cirrus cloud-detection portion of the spectrum, twothermal bands, improved sensor signal-to-noise performance and associated improvements in radiometric resolution, and an improved duty cycle that allows collection of a significantly greater number of images per day. This paper introduces the current (2012–2017) Landsat Science Team's efforts to establish an initial understanding of Landsat …

Evaluation And Application Of A New Shape-Sensitive Metric Useful For Characterizing Both Spectral Curves And Lidar Waveforms, Eric Ariel L. Salas

Electronic Theses and Dissertations

This dissertation seeks to investigate hyperspectral and waveform LiDAR datasets through a new analytical framework called Moment Distance method that uses a metric derived from the shape of the curve (spectral or waveform). In the case of hyperspectral data, the shape of the reflectance curve should unmask fine points of the spectra usually not considered by existing band-specific indices. To explore the advantages and shortcomings of this new approach, leaf and canopy hyperspectral reflectance samples were simulated using the physicallybased models PROSPECT (a leaf model) and SAIL (a canopy model). Sensitivity analysis was conducted with the goal of understanding the …

Fire Type Classification In The Brazilian Tropical Moist Forest Biome, Sanath Kumar Sathyachandran

Electronic Theses and Dissertations

The Brazilian Tropical Moist Forest Biome (BTMFB) is “Earth’s greatest biological treasure and a major component of the earth system” and forest degradation and deforestation by fire is a serious issue in this region. Fires in the BTMFB can be broadly classified as maintenance, deforestation and forest fire types. Spatially and temporally explicit information on the incidences of fire types are important as they have widely varying atmospheric emissions and ecological impacts. Satellite based remote sensing is a practical means of monitoring the BTMFB that spans almost 4 million km2. However, there has been no way to reliably …

Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer

Electronic Theses and Dissertations

Sagebrush (Artemisia spp.) ecosystems constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. Disturbances continue to alter this ecosystem, with climate change possibly representing the greatest future disturbance risk. Improved ways to characterize and monitor gradual change in this ecosystem are vital to its future management. A new remote sensing sagebrush characterization approach was developed in Wyoming which integrates three scales of remote sensing to derive four primary continuous field components (bare ground, herbaceousness, litter, and shrub), and four secondary components (sagebrush, big sagebrush, Wyoming sagebrush, and shrub …

Alternative Methods To Predict Actual Evapotranspiration Illustrate The Importance Of Accounting For Phenology: The Event Driven Phenology Model Part Ii, V. Kovalskyy, G. M. Henebry

Natural Resource Management Faculty Publications

Evapotranspiration (ET) flux constitutes a major component of both the water and energy balances at the land surface. Among the many factors that control evapotranspiration, phenology poses a major source of uncertainty in attempts to predict ET. Contemporary approaches to ET modeling and monitoring frequently summarize the complexity of the seasonal development of vegetation cover into static phenological trajectories (or climatologies) that lack sensitivity to changing environmental conditions. The Event Driven Phenology Model (EDPM) offers an alternative, interactive approach to representing phenology. This study presents the results of an experiment designed to illustrate the differences in ET arising from various …