A study on biological Co2 fixation in the sea on the earth
Shintaor Goto
Kanazawa Institute of Technology, Japan
Shunji Murai
Institute of Industrial Science University of Tokyo, Japan
Abstract
This study deals with the role of satellite Remote Sensing for monitoring global environment, and the analysis the places of the Co
2 fixation in the sea. The chlorophyll distribution produced from NIMBUS/CZCS data was used for estimation of the total capacity of Co
2 fixation in the sea area.
It is the first trial to estimate the ability of Co
2 fixation as the result of human activity using satellite data.
Introduction
From the statistics of fossil fuel consumption from Rotty & Marland (1986) we know that its consumption has increased from the middle of the last century to the present with about 3% annually with the present value of about 5.6 Gtc/year. On the other hand the atmospheric Co
2 concentration is 2.7Gtc/year. But the sink of the other Co
2 concentration is not known, it is called as a problem of missing sink.
May proposal to control global worming locally by fixing Co
2 concentration is presented. But the total balance of Co
2 in not cleared now. Especially the capacity of Co
2 fixation in the sea is estimated by the in situ observation data in these 30 years. So, we can't estimate the future capacity of Co
2 fixation by these data used now.
In this study, the new model to estimate the capacity of biological Co
2 fixation in the sea area using NIMBUS7/CZCS data is yield. After that the result from above is checked to the result of other studies.
Method
The data used in this study is NIMBUS/CZCS-level 3 (monthly averaged chlorophyll density), provided from NASA (Feldman et al., (1989)). Chlorophyll density is estimated by Gordon's algorithm (Gordon and Morel (1983)).
The calculation process of the capacity of Co
2 fixation in the sea is shown in Fig. 1.
The capacity of biological Co
2 fixation in the sea is estimated by net primary productivity of plankton. The process to estimate the distribution of plankton is shown in Fig. 2.
The chlorophyll distribution from Nimbus7/CZCS by Gordon's algorithm (See Fig. 3) is not effective in the region where aerosol density is high such as the region near Japan. But eh value is relatively effective in the small blocks such as each sea region.
Fig 1 Flow chart of estimation of Co2 fixation capacity.
Fig. 2 Flowchart to produce plankton map
Fig. 3. Chlorophyll distribution by Gordon's algorith
To estimate the primary from the chlorophyll density the correlation between chlorophyll density and primary productivity. But there is only one correlation made by Epply et al (1985) in near south and north America continent. Fig. 4 shows the relation between primary productivity : p (mgCm-2d-1) and chlorophyll density Ck : (mgm-3). And the correlation is as follows ;
Log (
p) = 3 + 0.5log (Ck)………………………………1)
