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Full-Text Articles in Life Sciences
Requirement Of Minimal Signal-To-Noise Ratios Of Ocean Color Sensors And Uncertainties Of Ocean Color Products, Lin Qi, Zhongping Lee, Chuanmin Hu, Menghua Wang
Requirement Of Minimal Signal-To-Noise Ratios Of Ocean Color Sensors And Uncertainties Of Ocean Color Products, Lin Qi, Zhongping Lee, Chuanmin Hu, Menghua Wang
Marine Science Faculty Publications
Using simulations, error propagation theory, and measurements from the Moderate Resolution Imaging Spectroradiometer (MODIS), we determined the minimal signal-to-noise ratio (SNR) required for ocean color measurements and product uncertainties at different spatial and temporal scales. First, based on typical top-of-atmosphere (TOA) radiance over the ocean, we evaluate the uncertainties in satellite-derived Rrs in the visible wavelengths (ΔRrs(vis)) due to sensor noise in both the near-infrared (NIR) and the visible bands. While the former induces noise in Rrs(vis) through atmospheric correction, the latter has a direct impact on Rrs(vis). Such estimated uncertainties are …
Land Adjacency Effects On Modis Aqua Top-Of-Atmosphere Radiance In The Shortwave Infrared: Statistical Assessment And Correction, Lian Feng, Chuanmin Hu
Land Adjacency Effects On Modis Aqua Top-Of-Atmosphere Radiance In The Shortwave Infrared: Statistical Assessment And Correction, Lian Feng, Chuanmin Hu
Marine Science Faculty Publications
Satellite measurements of coastal or inland waters near land/water interfaces suffer from land adjacency effects (LAEs), particularly in the short-wave infrared (SWIR) wavelengths. Here a statistical method was developed to quantify the LAEs as the ratio of top-of-atmosphere (TOA) total radiance (Lt, W m−2 µm−1 sr−1) between near-shore pixels and LAE-free offshore pixels (>12 pixels away from land). The calculations were conducted using MODIS Aqua images between 2003 and 2012 over the Madagascar Island, with results showing the dependency of LAEs on different environmental and observational factors. The LAEs decrease dramatically with increasing …
Satellite Observation Of Particulate Organic Carbon Dynamics On The Louisiana Continental Shelf, Chengfeng Le, John C. Lehrter, Chuanmin Hu, Hugh Macintyre, Marcus W. Beck
Satellite Observation Of Particulate Organic Carbon Dynamics On The Louisiana Continental Shelf, Chengfeng Le, John C. Lehrter, Chuanmin Hu, Hugh Macintyre, Marcus W. Beck
Marine Science Faculty Publications
Particulate organic carbon (POC) plays an important role in coastal carbon cycling and the formation of hypoxia. Yet, coastal POC dynamics are often poorly understood due to a lack of long-term POC observations and the complexity of coastal hydrodynamic and biogeochemical processes that influence POC sources and sinks. Using field observations and satellite ocean color products, we developed a new multiple regression algorithm to estimate POC on the Louisiana Continental Shelf (LCS) from satellite observations. The algorithm had reliable performance with mean relative error (MRE) of ∼40% and root mean square error (RMSE) of ∼50% for MODIS and SeaWiFS images …
Cloud And Sun-Glint Statistics Derived From Goes And Modis Observations Over The Intra-Americas Sea For Geo-Cape Mission Planning, Lian Feng, Chuanmin Hu, Brian B. Barnes, Antonio Mannino, Andrew K. Heidinger, Kathleen Strabala, Laura T. Iraci
Cloud And Sun-Glint Statistics Derived From Goes And Modis Observations Over The Intra-Americas Sea For Geo-Cape Mission Planning, Lian Feng, Chuanmin Hu, Brian B. Barnes, Antonio Mannino, Andrew K. Heidinger, Kathleen Strabala, Laura T. Iraci
Marine Science Faculty Publications
Knowledge of cloud cover, frequency, and duration is not only important to study cloud dynamics, but also critical in determining when and where to take ocean measurements from geostationary orbits such as the Geostationary Coastal and Air Pollution Events (GEO-CAPE) mission due to the challenges in achieving complete hemispheric coverage of coastal oceans, estuaries, and inland waters at hourly frequency. Using GOES hourly measurements at 4 km nadir resolution between 2006 and 2011, the number of cloud-free hourly observations per day (Ncf) for solar zenith angle θo < 80° was estimated for each 0.1° location of the Intra-Americas Sea. The number of Sun-glint-affected hourly observations per day (Nsg) was also calculated based on the …