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Full-Text Articles in Physical Sciences and Mathematics

A Cross Comparison Of Spatiotemporally Enhanced Springtime Phenological Measurements From Satellites And Ground In A Northern U.S. Mixed Forest, Liang Liang, Mark D. Schwartz, Zhuosen Wang, Feng Gao, Crystal B. Schaaf, Bin Tan, Jeffrey T. Morisette, Xiaoyang Zhang Dec 2014

A Cross Comparison Of Spatiotemporally Enhanced Springtime Phenological Measurements From Satellites And Ground In A Northern U.S. Mixed Forest, Liang Liang, Mark D. Schwartz, Zhuosen Wang, Feng Gao, Crystal B. Schaaf, Bin Tan, Jeffrey T. Morisette, Xiaoyang Zhang

GSCE Faculty Publications

Cross comparison of satellite-derived land surface phenology (LSP) and ground measurements is useful to ensure the relevance of detected seasonal vegetation change to the underlying biophysical processes. While standard 16-day and 250-m Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation index (VI)-based springtime LSP has been evaluated in previous studies, it remains unclear whether LSP with enhanced temporal and spatial resolutions can capture additional details of ground phenology. In this paper, we compared LSP derived from 500-m daily MODIS and 30-m MODIS-Landsat fused VI data with landscape phenology (LP) in a northern U.S. mixed forest. LP was previously developed from intensively observed …


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 Jul 2014

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 Jun 2014

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 …


Interannual Variations And Trends In Global Land Surface Phenology Derived From Enhanced Vegetation Index During 1982–2010, Xiaoyang Zhang, Bin Tan, Yunyue Yu May 2014

Interannual Variations And Trends In Global Land Surface Phenology Derived From Enhanced Vegetation Index During 1982–2010, Xiaoyang Zhang, Bin Tan, Yunyue Yu

GSCE Faculty Publications

Land surface phenology is widely retrieved from satellite observations at regional and global scales, and its long-term record has been demonstrated to be a valuable tool for reconstructing past climate variations, monitoring the dynamics of terrestrial ecosystems in response to climate impacts, and predicting biological responses to future climate scenarios. This study detected global land surface phenology from the advanced very high resolution radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) data from 1982 to 2010. Based on daily enhanced vegetation index at a spatial resolution of 0.05 degrees, we simulated the seasonal vegetative trajectory for each individual pixel …


Detecting The Influence Of Best Management Practices On Vegetation Near Ephemeral Streams With Landsat Data, Matthew Rigge, Alexander Smart, Bruce Wylie, Kendall De Van Kamp Jan 2014

Detecting The Influence Of Best Management Practices On Vegetation Near Ephemeral Streams With Landsat Data, Matthew Rigge, Alexander Smart, Bruce Wylie, Kendall De Van Kamp

Natural Resource Management Faculty Publications

Various best management practices (BMPs) have been implemented on rangelands with the goals of controlling nonpoint sourcepollution, reducing the impact of livestock in ecologically important riparian areas, and improving grazing distribution.Providing off-stream water sources to livestock in pastures, cross-fencing, and rotational grazing are common rangeland BMPsthat have demonstrated success in drawing livestock grazing pressure away from streams. We evaluated the effects of rangelandBMP implementation with six commercial-scale pastures in the northern mixed-grass prairie. Four pastures received a BMPsuite consisting of off-stream water, cross-fencing, and deferred-rotation grazing, and two pastures did not receive BMPs. Wehypothesized that the BMPs increased the quantity …