A new parameterization of spectral and broadband ocean surface albedo

Abstract An analysis of several ocean surface albedo (OSA) schemes is undertaken through offline comparisons and through application in the Canadian Centre for Climate Modelling and Analysis (CCCma) fourth-generation atmospheric general circulation model (AGCM4). In general, each scheme requires different input quantities to determine the OSA. Common to all schemes is a dependence on the solar zenith angle (SZA). A direct comparison of the SZA dependence of the schemes reveals significant differences in the predicted albedos. Other input quantities include wind speed and aerosol/cloud optical depth, which are also analyzed. An offline one-dimensional radiative transfer model is used to quantitatively study the impact of ocean surface albedo on the radiative transfer process. It is found that, as a function of SZA and wind speed, the difference in reflected solar flux at the top of the atmosphere is in general agreement between OSA schemes that depend on these quantities, with a difference <10 W m−2. However, for simpler schemes that depend only on SZA the difference in this flux can approach 10–20 W m−2. The impact of the different OSA schemes is assessed through multiyear simulations of present-day climate in AGCM4. Five-year means of the reflected clear-sky flux at the top of the atmosphere reveal local differences of up to several watts per meters squared between any of the schemes. Globally, all schemes display a similar negative bias relative to the Earth Radiation Budget Experiment (ERBE) observations. This negative bias is largely reduced by comparison with the recently released Clouds and the Earth’s Radiant Energy System (CERES) data. It is shown that the local upward clear-sky flux at the surface is more sensitive to the OSA formulation than the clear-sky upward flux at the top of atmosphere. It is found that the global energy balance of the model at the top of the atmosphere and at the surface is surprisingly insensitive to which OSA scheme is employed.

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An interactive ocean surface albedo scheme (OSAv1.0): formulation and evaluation in ARPEGE-Climat (V6.1) and LMDZ (V5A)

Geoscientific Model Development ◽

10.5194/gmd-11-321-2018 ◽

2018 ◽

Vol 11 (1) ◽

pp. 321-338 ◽

Cited By ~ 11

Author(s):

Roland Séférian ◽

Sunghye Baek ◽

Olivier Boucher ◽

Jean-Louis Dufresne ◽

Bertrand Decharme ◽

...

Keyword(s):

Surface Albedo ◽

Diffuse Radiation ◽

Ocean Surface ◽

Ocean Waves ◽

Global Scale ◽

Shortwave Radiation ◽

Earth System ◽

Diffuse Solar Radiation ◽

System Models ◽

Earth System Models

Abstract. Ocean surface represents roughly 70 % of the Earth's surface, playing a large role in the partitioning of the energy flow within the climate system. The ocean surface albedo (OSA) is an important parameter in this partitioning because it governs the amount of energy penetrating into the ocean or reflected towards space. The old OSA schemes in the ARPEGE-Climat and LMDZ models only resolve the latitudinal dependence in an ad hoc way without an accurate representation of the solar zenith angle dependence. Here, we propose a new interactive OSA scheme suited for Earth system models, which enables coupling between Earth system model components like surface ocean waves and marine biogeochemistry. This scheme resolves spectrally the various contributions of the surface for direct and diffuse solar radiation. The implementation of this scheme in two Earth system models leads to substantial improvements in simulated OSA. At the local scale, models using the interactive OSA scheme better replicate the day-to-day distribution of OSA derived from ground-based observations in contrast to old schemes. At global scale, the improved representation of OSA for diffuse radiation reduces model biases by up to 80 % over the tropical oceans, reducing annual-mean model–data error in surface upwelling shortwave radiation by up to 7 W m−2 over this domain. The spatial correlation coefficient between modeled and observed OSA at monthly resolution has been increased from 0.1 to 0.8. Despite its complexity, this interactive OSA scheme is computationally efficient for enabling precise OSA calculation without penalizing the elapsed model time.

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An interactive ocean surface albedo scheme: formulation and evaluation in two atmospheric models

10.5194/gmd-2017-111 ◽

2017 ◽

Cited By ~ 2

Author(s):

Roland Séférian ◽

Sunghye Baek ◽

Olivier Boucher ◽

Jean-Louis Dufresne ◽

Bertrand Decharme ◽

...

Keyword(s):

Surface Albedo ◽

Ad Hoc ◽

Diffuse Radiation ◽

Ocean Surface ◽

Global Scale ◽

Shortwave Radiation ◽

Earth System ◽

Diffuse Solar Radiation ◽

System Models ◽

Earth System Models

Abstract. Ocean surface represents roughly 70 % of the Earth surface, playing a large role in the partitioning of the energy flow within the climate system. The ocean surface albedo (OSA) is an important parameter in this partitioning because it governs the amount of energy penetrating into the ocean or reflected towards space. The old OSA schemes in the ARPEGE and LMDZ models only resolve the latitudinal dependence in an ad hoc way without an accurate representation of the solar zenith angle dependence. Here, we propose a new interactive OSA scheme suited for Earth system models, which gather contributions for relevant OSA processes published in the literature over the last decades. This scheme resolves spectrally the various contributions of the surface for direct and diffuse solar radiation. The implementation of this scheme in two Earth system models leads to substantial improvements in simulated OSA. At the local scale, models using the interactive OSA scheme better replicate the day-to-day distribution of OSA derived from ground-based observations in contrast to old schemes. At global scale, the improved representation of OSA for diffuse radiation reduces model biases by up to 80 % over the tropical oceans, reducing annual-mean model-data error in surface upwelling shortwave radiation by up to 7 W m−2 over this domain. The spatial correlation coefficient between modelled and observed OSA at monthly resolution has been increased from 0.1 to 0.8. Despite its complexity, this interactive OSA scheme is computationally efficient to enable precise OSA calculation without penalizing the model elapsed time.

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Ocean surface albedo in AFES

JAMSTEC Report of Research and Development ◽

10.5918/jamstecr.6.21 ◽

2007 ◽

Vol 6 (0) ◽

pp. 21-30 ◽

Cited By ~ 4

Author(s):

Takeshi Enomoto

Keyword(s):

Surface Albedo ◽

Ocean Surface

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An evaluation of the schemes of ocean surface albedo parameterization in shortwave radiation estimation

10.1117/12.2207426 ◽

2015 ◽

Author(s):

Hailin Niu ◽

Xiaotong Zhang ◽

Qiang Liu ◽

Youbin Feng ◽

Xiuhong Li ◽

...

Keyword(s):

Surface Albedo ◽

Ocean Surface ◽

Shortwave Radiation

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Daily spectral ocean surface albedo (OSA) parameterization in case of clearness index (Kt) and phytoplankton variability in Malacca Strait

Estuarine Coastal and Shelf Science ◽

10.1016/j.ecss.2020.106939 ◽

2020 ◽

Vol 244 ◽

pp. 106939

Author(s):

Philipp Golovchenko ◽

Yusri Yusup ◽

Liew Juneng ◽

Fredolin T. Tangang

Keyword(s):

Surface Albedo ◽

Ocean Surface ◽

Clearness Index ◽

Phytoplankton Variability ◽

Malacca Strait

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An improved ocean surface albedo computational scheme: Structure and Performance

Journal of Geophysical Research Oceans ◽

10.1029/2020jc016958 ◽

2021 ◽

Author(s):

Jian Wei ◽

Tong Ren ◽

Ping Yang ◽

Steven F. DiMarco ◽

Eli Mlawer

Keyword(s):

Surface Albedo ◽

Ocean Surface ◽

Computational Scheme ◽

And Performance

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MAPPING GLOBAL OCEAN SURFACE ALBEDO FROM SATELLITE OBSERVATIONS: MODELS, ALGORITHMS, AND DATASETS

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-3-967-2018 ◽

2018 ◽

Vol XLII-3 ◽

pp. 967-970

Author(s):

X. Li ◽

X. Fan ◽

H. Yan ◽

A. Li ◽

M. Wang ◽

...

Keyword(s):

Land Surface ◽

Surface Albedo ◽

Global Climate ◽

Estimation Method ◽

Ocean Surface ◽

Satellite Observations ◽

Surface Radiation ◽

Radiation Budget ◽

Global Ocean ◽

Ocean Water

Ocean surface albedo (OSA) is one of the important parameters in surface radiation budget (SRB). It is usually considered as a controlling factor of the heat exchange among the atmosphere and ocean. The temporal and spatial dynamics of OSA determine the energy absorption of upper level ocean water, and have influences on the oceanic currents, atmospheric circulations, and transportation of material and energy of hydrosphere. Therefore, various parameterizations and models have been developed for describing the dynamics of OSA. However, it has been demonstrated that the currently available OSA datasets cannot full fill the requirement of global climate change studies. In this study, we present a literature review on mapping global OSA from satellite observations. The models (parameterizations, the coupled ocean-atmosphere radiative transfer (COART), and the three component ocean water albedo (TCOWA)), algorithms (the estimation method based on reanalysis data, and the direct-estimation algorithm), and datasets (the cloud, albedo and radiation (CLARA) surface albedo product, dataset derived by the TCOWA model, and the global land surface satellite (GLASS) phase-2 surface broadband albedo product) of OSA have been discussed, separately.

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