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Physical and Environmental Geography Commons

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Articles 1 - 7 of 7

Full-Text Articles in Physical and Environmental Geography

Land Surface Phenologies And Seasonalities Using Cool Earthlight In Mid-Latitude Croplands, W. G. Alemu, G. M. Henebry Oct 2016

Land Surface Phenologies And Seasonalities Using Cool Earthlight In Mid-Latitude Croplands, W. G. Alemu, G. M. Henebry

Geoffrey Henebry

Phenology deals with timing of biotic phenomena and seasonality concerns temporal patterns of abiotic variables. Studies of land surface phenology (LSP) and land surface seasonality (LSS) have long been limited to visible to near infrared (VNIR) wavelengths, despite degradation by atmospheric effects and solar illumination constraints. Enhanced land surface parameters derived from passive microwave data enable improved temporal monitoring of agricultural land surface dynamics compared to the vegetation index data available from VNIR data. LSPs and LSSs in grain growing regions of the Volga River Basin of Russia and the spring wheat belts of the USA and Canada were characterized …


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 Oct 2016

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

Geoffrey Henebry

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 …


Remote Sensing-Based Time Series Models For Malaria Early Warning In The Highlands Of Ethiopia, A. Midekisa, G. Senay, G. M. Henebry, P. Semuniguse, M. C. Wimberly Oct 2016

Remote Sensing-Based Time Series Models For Malaria Early Warning In The Highlands Of Ethiopia, A. Midekisa, G. Senay, G. M. Henebry, P. Semuniguse, M. C. Wimberly

Geoffrey Henebry

Background

Malaria is one of the leading public health problems in most of sub-Saharan Africa, particularly in Ethiopia. Almost all demographic groups are at risk of malaria because of seasonal and unstable transmission of the disease. Therefore, there is a need to develop malaria early-warning systems to enhance public health decision making for control and prevention of malaria epidemics. Data from orbiting earth-observing sensors can monitor environmental risk factors that trigger malaria epidemics. Remotely sensed environmental indicators were used to examine the influences of climatic and environmental variability on temporal patterns of malaria cases in the Amhara region of Ethiopia. …


Dual Scale Trend Analysis Distinguishes Climatic From Anthropogenic Effects On The Vegetated Land Surface, K. M. De Beurs, C. K. Wright, G. M. Henebry Oct 2016

Dual Scale Trend Analysis Distinguishes Climatic From Anthropogenic Effects On The Vegetated Land Surface, K. M. De Beurs, C. K. Wright, G. M. Henebry

Geoffrey Henebry

We present a dual scale trend analysis for characterizing and comparing two contrasting areas of change in Russia and Kazakhstan that lie less than 800 km apart. We selected a global NASA MODIS (moderate resolution imaging spectroradiometer) product (MCD43C4 and MCD43A4) at a 0.05◦ (∼5.6 km) and 500 m spatial resolution and a 16-day temporal resolution from 2000 to 2008. We applied a refinement of the seasonal Kendall trend method to the normalized difference vegetation index (NDVI) image series at both scales. We only incorporated composites during the vegetative growing season which was delineated by start of season and end …


Evaluation Of A Coupled Event-Driven Phenology And Evapotranspiration Model For Croplands In The United States Northern Great Plains, V. Kovalskyy, G. M. Henebry, D. P. Roy, B. Adusei, M. Hansen, G. Senay, D. M. Mocko Oct 2016

Evaluation Of A Coupled Event-Driven Phenology And Evapotranspiration Model For Croplands In The United States Northern Great Plains, V. Kovalskyy, G. M. Henebry, D. P. Roy, B. Adusei, M. Hansen, G. Senay, D. M. Mocko

Geoffrey Henebry

A new model coupling scheme with remote sensing data assimilation was developed for estimation of daily actual evapotranspiration (ET). The scheme consists of the VegET, a model to estimate ET from meteorological and water balance data, and an Event Driven Phenology Model (EDPM), an empirical crop specific model trained on multiple years of flux tower data transformed into six types of environmental forcings that are called “events” to emphasize their temporally discrete character, which has advantages for modeling multiple contingent influences. The EDPM in prognostic mode supplies seasonal trajectories of normalized difference vegetation index (NDVI); whereas in diagnostic mode, it …


A New Approach For The Analysis Of Hyperspectral Data: Theory And Sensitivity Analysis Of The Moment Distance Method, E.A. L. Salas, G. M. Henebry Oct 2016

A New Approach For The Analysis Of Hyperspectral Data: Theory And Sensitivity Analysis Of The Moment Distance Method, E.A. L. Salas, G. M. Henebry

Geoffrey Henebry

We present the Moment Distance (MD) method to advance spectral analysis in vegetation studies. It was developed to take advantage of the information latent in the shape of the reflectance curve that is not available from other spectral indices. Being mathematically simple but powerful, the approach does not require any curve transformation, such as smoothing or derivatives. Here, we show the formulation of the MD index (MDI) and demonstrate its potential for vegetation studies. We simulated leaf and canopy reflectance samples derived from the combination of the PROSPECT and SAIL models to understand the sensitivity of the new method to …


Proceedings Of The Workshop On Spatio-Temporal Data Models Of Biogeophysical Fields For Ecological Forecasting, Geoffrey Henebry, Jan Chomicki, Tony Fountain Mar 2002

Proceedings Of The Workshop On Spatio-Temporal Data Models Of Biogeophysical Fields For Ecological Forecasting, Geoffrey Henebry, Jan Chomicki, Tony Fountain

Geoffrey Henebry

This workshop was held on April 8th - 10th at the San Diego Supercomputer Center in La Jolla, California. It was sponsored by the National Science Foundation.

Workshop Overview
We are now in an era of intensive earth observation: orbital platforms generate myriad
remote sensing datastreams across a range of spatial, temporal, spectral, and radiometric
resolutions. The number and variety of "eyes in the skies" are scheduled to increase
significantly over the next few years. Tiris veritable data deluge necessitates new ways of
thinking about transforming remote sensing data into information about ecological patterns and
processes. These datastreams hold the …