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Physical Sciences and Mathematics Commons™
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Full-Text Articles in Physical Sciences and Mathematics
Reduction Of The Long-Term Inaccuracy From The Avhrr–Based Ndvi Data, Md Zahidur Rahman, Leonid Roytman, M. Nazrul Islam
Reduction Of The Long-Term Inaccuracy From The Avhrr–Based Ndvi Data, Md Zahidur Rahman, Leonid Roytman, M. Nazrul Islam
Publications and Research
This paper investigated the normalized difference vegetation index (NDVI) stability in the NOAA/NESDIS Global Vegetation Index (GVI) data during 1982-2003, which was collected from five NOAA series satellites. An empirical distribution function (EDF) was developed to eliminate the long-term inaccuracy of the NDVI data derived from the AVHRR sensor on NOAA polar orbiting satellite. The instability of data results from orbit degradation as well as from the circuit drifts over the life of a satellite. Degradation of NDVI over time and shifts of NDVI between the satellites were estimated using the China data set, because it includes a wide variety …
Global Trends In Seasonality Of Normalized Difference Vegetation Index (Ndvi), 1982–2011, J. Ronald Eastman, Florencia Sangermano, Elia Axinia Machado, John Rogan, Assaf Anyamba
Global Trends In Seasonality Of Normalized Difference Vegetation Index (Ndvi), 1982–2011, J. Ronald Eastman, Florencia Sangermano, Elia Axinia Machado, John Rogan, Assaf Anyamba
Publications and Research
A 30-year series of global monthly Normalized Difference Vegetation Index (NDVI) imagery derived from the Global Inventory Modeling and Mapping Studies (GIMMS) NDVI3g archive was analyzed for the presence of trends in changing seasonality. Using the Seasonal Trend Analysis (STA) procedure, over half (56.30%) of land surfaces were found to exhibit significant trends. Almost half (46.10%) of the significant trends belonged to three classes of seasonal trends (or changes). Class 1 consisted of areas that experienced a uniform increase in NDVI throughout the year, and was primarily associated with forested areas, particularly broadleaf forests. Class 2 consisted of areas experiencing …
Validation Of Noaa-Interactive Multisensor Snow And Ice Mapping System (Ims) By Comparison With Ground-Based Measurements Over Continental United States, Christine Chen, Tarendra Lakhankar, Peter Romanov, Sean Helfrich, Al Powell, Reza Khanbilvardi
Validation Of Noaa-Interactive Multisensor Snow And Ice Mapping System (Ims) By Comparison With Ground-Based Measurements Over Continental United States, Christine Chen, Tarendra Lakhankar, Peter Romanov, Sean Helfrich, Al Powell, Reza Khanbilvardi
Publications and Research
In this study, daily maps of snow cover distribution and sea ice extent produced by NOAA’s interactive multisensor snow and ice mapping system (IMS) were validated using in situ snow depth data from observing stations obtained from NOAA’s National Climatic Data Center (NCDC) for calendar years 2006 to 2010. IMS provides daily maps of snow and sea ice extent within the Northern Hemisphere using data from combination of geostationary and polar orbiting satellites in visible, infrared and microwave spectrums. Statistical correspondence between the IMS and in situ point measurements has been evaluated assuming that ground measurements are discrete and continuously …