The influence of input uncertainties on remotely sensed estimates of ocean primary productivity
Temporally and spatially dense estimates of oceanic phytoplankton net primary productivity (NPP), which are commonly derived by mathematical models from satellite observations of ocean colour, are a cornerstone of current research efforts focused on the state and variability of ecosystems, biogeoche...
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ftunivbergen:oai:bora.uib.no:1956/4819 2023-05-15T17:36:30+02:00 The influence of input uncertainties on remotely sensed estimates of ocean primary productivity Milutinović, Svetlana 2011-06-10 application/pdf https://hdl.handle.net/1956/4819 eng eng The University of Bergen Paper I: Global Biogeochemical Cycles 23, GB4005, Milutinović, Svetlana; Behrenfeld, Michael J.; Johannessen, Johnny A. and Truls Johannessen, Sensitivity of Remote Sensing–Derived Phytoplankton Productivity to Mixed Layer Depth: Lessons from the Carbon-based Productivity Model. Published version. Copyright 2009 American Geophysical Union. Paper II: Remote Sensing of Environment 115(8), Svetlana Milutinović and Laurent Bertino, Assessment and Propagation of Uncertainties in Input Terms through an Ocean-Colour-Based Model of Primary Productivity. Accepted version. Copyright 2011 Elsevier. The published version is available at: http://dx.doi.org/10.1016/j.rse.2011.03.013 Paper III: Svetlana Milutinović, Uncertainty in a Model for Estimating Euphotic Depth from Satellite Observations of Chlorophyll. Published 2011 in NERSC Special Report 88, Nansen Environmental and Remote Sensing Center, Bergen, Norway. urn:isbn:978-82-308-1771-1 (print version) https://hdl.handle.net/1956/4819 Attribution-NonCommercial CC BY-NC http://creativecommons.org/licenses/by-nc/3.0/ The author Copyright the author. Some rights reserved. The permission for use of this work is granted in accordance with the terms of the Creative Commons Attribution-NonCommercial 3.0 Unported License. VDP::Mathematics and natural science: 400::Physics: 430 Doctoral thesis 2011 ftunivbergen https://doi.org/10.1016/j.rse.2011.03.013 2023-03-14T17:40:40Z Temporally and spatially dense estimates of oceanic phytoplankton net primary productivity (NPP), which are commonly derived by mathematical models from satellite observations of ocean colour, are a cornerstone of current research efforts focused on the state and variability of ecosystems, biogeochemical cycles and climate. Using two exemplary NPP models, it was examined how uncertainties in model input terms might affect the accuracy of the output. In the first part of the dissertation, the response of NPP estimates to perturbing input values of mixed layer depth (MLD) was analyzed. Four series of NPP fields, two global and two covering the North Atlantic, were computed in monthly intervals during a period of several years. Each of the series resulted from identical remote sensing data but different MLD input. Due to the influence of MLD on the availability of light for photosynthesis, the NPP estimates were overall inversely related to MLD. However, the degree of this relationship varied considerably in space and time over most of the world ocean. During summer, NPP at middle and high latitudes was appreciably sensitive even to small MLD fluctuations, but had little or no response to large MLD perturbations in winter. On the other hand, subtropical regions were characterized by a largely opposite seasonal pattern. Tropical areas showed no seasonality and, apart from the equatorial Pacific, exhibited little sensitivity of NPP to MLD uncertainties. The observed variability in the NPP response was attributed not only to the model’s nonlinearity, but also to the presence of the photosynthetic saturation/limitation thresholds, as well as to the coincident sea surface irradiance and, in particular, the diffuse attenuation coefficient for downward irradiance (Kd). It was shown that Kd could be used as an indicator of the NPP sensitivity to uncertainties in MLD, the greatest sensitivity being associated with very large Kd values. Maximum differences between areally integrated annual NPP estimates, based on different ... Doctoral or Postdoctoral Thesis North Atlantic University of Bergen: Bergen Open Research Archive (BORA-UiB) Pacific Remote Sensing of Environment 115 8 1906 1917 |
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Open Polar |
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University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
topic |
VDP::Mathematics and natural science: 400::Physics: 430 |
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VDP::Mathematics and natural science: 400::Physics: 430 Milutinović, Svetlana The influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
topic_facet |
VDP::Mathematics and natural science: 400::Physics: 430 |
description |
Temporally and spatially dense estimates of oceanic phytoplankton net primary productivity (NPP), which are commonly derived by mathematical models from satellite observations of ocean colour, are a cornerstone of current research efforts focused on the state and variability of ecosystems, biogeochemical cycles and climate. Using two exemplary NPP models, it was examined how uncertainties in model input terms might affect the accuracy of the output. In the first part of the dissertation, the response of NPP estimates to perturbing input values of mixed layer depth (MLD) was analyzed. Four series of NPP fields, two global and two covering the North Atlantic, were computed in monthly intervals during a period of several years. Each of the series resulted from identical remote sensing data but different MLD input. Due to the influence of MLD on the availability of light for photosynthesis, the NPP estimates were overall inversely related to MLD. However, the degree of this relationship varied considerably in space and time over most of the world ocean. During summer, NPP at middle and high latitudes was appreciably sensitive even to small MLD fluctuations, but had little or no response to large MLD perturbations in winter. On the other hand, subtropical regions were characterized by a largely opposite seasonal pattern. Tropical areas showed no seasonality and, apart from the equatorial Pacific, exhibited little sensitivity of NPP to MLD uncertainties. The observed variability in the NPP response was attributed not only to the model’s nonlinearity, but also to the presence of the photosynthetic saturation/limitation thresholds, as well as to the coincident sea surface irradiance and, in particular, the diffuse attenuation coefficient for downward irradiance (Kd). It was shown that Kd could be used as an indicator of the NPP sensitivity to uncertainties in MLD, the greatest sensitivity being associated with very large Kd values. Maximum differences between areally integrated annual NPP estimates, based on different ... |
format |
Doctoral or Postdoctoral Thesis |
author |
Milutinović, Svetlana |
author_facet |
Milutinović, Svetlana |
author_sort |
Milutinović, Svetlana |
title |
The influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
title_short |
The influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
title_full |
The influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
title_fullStr |
The influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
title_full_unstemmed |
The influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
title_sort |
influence of input uncertainties on remotely sensed estimates of ocean primary productivity |
publisher |
The University of Bergen |
publishDate |
2011 |
url |
https://hdl.handle.net/1956/4819 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Paper I: Global Biogeochemical Cycles 23, GB4005, Milutinović, Svetlana; Behrenfeld, Michael J.; Johannessen, Johnny A. and Truls Johannessen, Sensitivity of Remote Sensing–Derived Phytoplankton Productivity to Mixed Layer Depth: Lessons from the Carbon-based Productivity Model. Published version. Copyright 2009 American Geophysical Union. Paper II: Remote Sensing of Environment 115(8), Svetlana Milutinović and Laurent Bertino, Assessment and Propagation of Uncertainties in Input Terms through an Ocean-Colour-Based Model of Primary Productivity. Accepted version. Copyright 2011 Elsevier. The published version is available at: http://dx.doi.org/10.1016/j.rse.2011.03.013 Paper III: Svetlana Milutinović, Uncertainty in a Model for Estimating Euphotic Depth from Satellite Observations of Chlorophyll. Published 2011 in NERSC Special Report 88, Nansen Environmental and Remote Sensing Center, Bergen, Norway. urn:isbn:978-82-308-1771-1 (print version) https://hdl.handle.net/1956/4819 |
op_rights |
Attribution-NonCommercial CC BY-NC http://creativecommons.org/licenses/by-nc/3.0/ The author Copyright the author. Some rights reserved. The permission for use of this work is granted in accordance with the terms of the Creative Commons Attribution-NonCommercial 3.0 Unported License. |
op_doi |
https://doi.org/10.1016/j.rse.2011.03.013 |
container_title |
Remote Sensing of Environment |
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115 |
container_issue |
8 |
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1906 |
op_container_end_page |
1917 |
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1766135996033794048 |