TY - JOUR
T1 - Global Distribution of Case-1 Waters: An Analysis from SeaWiFS Measurements
AU - Lee, ZhongPing
AU - Hu, Chuanmin
PY - 2006/1/1
Y1 - 2006/1/1
N2 - “Case-1” has been a term frequently used to characterize water type since the seventies. However, the distribution of Case-1 waters in global scale has been vague, though open ocean waters are often referred to as Case-1 in the literature. In this study, based on recent bio-optical models for Case-1 waters, an inclusive and quantitative Case-1 criterion for remote sensing applications is developed. The criterion allows Case-1 waters to have about two-fold variations of non-pigment absorption and particle backscattering around their exact Case-1 values, allowing a large range of waters to be classified as Case-1. Even so, application of this criterion to ocean color data from the SeaWiFS satellite sensor suggests that Case-1 waters occupy only about 60% of the global ocean surface. Regionally, more Case-1 waters are found in the southern hemisphere than in the northern hemisphere, and most Indian Ocean waters are found to be Case-1. The Case-1 percentage and spatial distribution change with season, and with the boundaries chosen in the criterion. Nevertheless, this study for the first time provides a quantitative and geographical perspective of Case-1 waters in global scale, and further demonstrates that many open ocean waters are not necessarily Case-1.
AB - “Case-1” has been a term frequently used to characterize water type since the seventies. However, the distribution of Case-1 waters in global scale has been vague, though open ocean waters are often referred to as Case-1 in the literature. In this study, based on recent bio-optical models for Case-1 waters, an inclusive and quantitative Case-1 criterion for remote sensing applications is developed. The criterion allows Case-1 waters to have about two-fold variations of non-pigment absorption and particle backscattering around their exact Case-1 values, allowing a large range of waters to be classified as Case-1. Even so, application of this criterion to ocean color data from the SeaWiFS satellite sensor suggests that Case-1 waters occupy only about 60% of the global ocean surface. Regionally, more Case-1 waters are found in the southern hemisphere than in the northern hemisphere, and most Indian Ocean waters are found to be Case-1. The Case-1 percentage and spatial distribution change with season, and with the boundaries chosen in the criterion. Nevertheless, this study for the first time provides a quantitative and geographical perspective of Case-1 waters in global scale, and further demonstrates that many open ocean waters are not necessarily Case-1.
KW - Case-1
KW - Case-2
KW - Ocean color
KW - Remote sensing
KW - Bio-optical model
UR - https://digitalcommons.usf.edu/msc_facpub/2017
UR - https://doi.org/10.1016/j.rse.2005.11.008
U2 - 10.1016/j.rse.2005.11.008
DO - 10.1016/j.rse.2005.11.008
M3 - Article
VL - 101
JO - Remote Sensing of Environment
JF - Remote Sensing of Environment
ER -