CO2 concentration correcting apparatus and CO2 concentration correcting method

Hourly CO2 concentration, amount of solar radiation, and plant distribution information are calculated through observation from predetermined satellites. A concentration of CO2 absorbed by plant-chlorophyll per each time unit is calculated. By adding up the CO2 concentration on the earth and the concentration of CO2 absorbed by the plant-chlorophyll, a CO2 concentration obtained provided that no plant-chlorophyll exist is calculated for a certain period. Thereafter, a mean concentration of CO2 that is absorbed according to changes in the distribution of plant-chlorophyll is calculated on the basis of a monthly mean solar radiation amount and plant-chlorophyll distribution information. By subtracting the CO2 concentration, which is a mean, from the total CO2 concentration, a CO2 concentration, which is a normal, is calculated.

FIELD

The embodiment discussed herein is directed to a CO2concentration correcting apparatus and a CO2concentration correcting method.

BACKGROUND

Global warming with its increase in CO2levels has become a social issue. Thus, it is necessary to reduce CO2emissions and reduce excessive emitted CO2through green campaigns, for example, planting plants. For this reason, objectives have been established to accurately understand the latest distribution of CO2, plants that absorb CO2by photosynthesis, and the distribution of chlorophyll.

Conventionally, the amount of CO2is directly observed by instruments with which, for example, aircraft are equipped. However, because the observed values obtained by the instruments through their measurements is information limited to a specific point, the spatial actual amount and the distribution of chlorophyll cannot be uniformly understood. Thus, the amount of CO2on the earth cannot be accurately known. Therefore, a definite policy of green schemes cannot be established and only limited measurements have been taken for in regions where tree-planting can be carried out.

However, the Greenhouse Gases Observing Satellite (GOSAT) and the US Orbiting Carbon Observatory (OCO), which can observe the CO2concentration on the earth, have been developed in recent years. Observations by the GOSAT and OCO allow us to know the distribution of CO2. Accordingly, global distribution data on the CO2concentrations can be obtained.

For example, Patent Document 1 discloses, as conventional technologies related to the concentration distribution of CO2, a planting support system that can carry out appropriate planting schemes in consideration of the chronological changes of plants by calculating the amount of CO2in the atmosphere in accordance with planting with regard to each type of plant.Patent Document 1: Japanese Laid-open Patent Publication No. 2000-12345

DISCLOSURE OF INVENTION

Problem to be Solved by the Invention

Conventionally, CO2concentration is observed by the GOSAT and the observed CO2concentration is regarded as the CO2concentration on the earth. However, there is a problem in that the data that is obtained by the GOSAT through observations is not the value of the CO2concentration for the normal weather. In other words, for the value of the CO2concentration that is used as a CO2reduction target value, it is necessary to consider the effects from plants and chlorophyll that absorb CO2by photosynthesis. However, the current methods do not consider such effects.

In other words, effects from the weather on the CO2that plants and chlorophyll absorb are not considered for the value of the CO2concentration observed by these satellites. There is a problem in that, although there are seasonal variations and daily variations in the amount of absorbed CO2according to the activities of vegetation according to changes in the amount of solar radiation, corrections are not made for those variations and changes. Specifically, for example, when there are a lot of sunny days (a large amount of solar radiation) and plants actively photosynthesize, a smaller amount of CO2is observed compared to a year with a lot of cloudy days.

SUMMARY

According to an aspect of an embodiment of the invention, an apparatus includes an observed CO2amount storage unit (14) that stores an observed CO2amount that is an amount of CO2that is observed in an observation region; a plant-chlorophyll distribution information storage unit (11) that stores plant-chlorophyll distribution information on distribution of plant-chlorophyll in the observation region; a solar radiation amount storage unit (13) that stores an amount of solar radiation in the observation region; an absorbed CO2amount calculating unit that calculates an absorbed CO2amount that is an amount of CO2that is absorbed by the plant-chlorophyll on the basis of the plant-chlorophyll distribution information and the amount of solar radiation; a total CO2amount calculating unit that calculates a total CO2amount by adding up the observed CO2amount and the absorbed CO2amount; an average solar radiation amount storage unit that stores an average solar radiation amount in the observation region; an average absorbed CO2amount calculating unit that calculates an average absorbed CO2amount that is an average amount of CO2that is absorbed by plant-chlorophyll when a solar radiation amount is the average solar radiation amount; and a corrected CO2amount calculating unit that calculates a corrected CO2amount by subtracting the average absorbed CO2amount from the total CO2amount.

DESCRIPTION OF EMBODIMENT

Embodiments of a CO2concentration correcting apparatus, a CO2concentration correcting method, and a CO2concentration correcting program according to the present invention will be explained below with reference to the accompanying drawings. Explanations of an overview of a plurality of observation satellites that are used in the embodiments, of an overview and features of a CO2concentration correcting apparatus according to a first embodiment, of an overview of a process of the CO2concentration correcting apparatus, for a configuration of the CO2concentration correcting apparatus, and of a flow of the process of the CO2concentration correcting apparatus will be provided in the sequence they appear in this sentence, and explanations of the effects from the first embodiment will be provided last.

Explanation of Overview of Observation Satellites

A CO2concentration correcting apparatus1illustrated in the first embodiment receives observation information (a CO2concentration, an amount of solar radiation, a distribution amount of plants, and a distribution amount of chlorophyll) and corrects the CO2concentration on the basis of the observation information. First, an overview of the observation satellites will be given.

The Greenhouse Gases Observing Satellite (GOSAT) is a greenhouse gas observation technology satellite that is a satellite that observes the CO2concentration on the earth. The Orbiting Carbon Observatory (OCO) is a US CO2observation satellite that can observe the CO2concentration as the GOSAT can.

The NOAA satellite is a satellite that was launched by the National Oceanic and Atmospheric Administration (NOAA). The NOAA satellite can obtain data on vegetation (vegetation index SR) on the earth through observation.

The Multi-functional Transport Satellites (MTSAT) are transportation multi-purpose satellites that observe the amount of solar radiation on the basis of the distribution of clouds over the earth. Besides using MTSAT, the amount of solar radiation can be estimated from data from the Geostationary Operational Environmental Satellites (GOES), which are US stationary weather satellites and the Metrology Satellites (METEOSAT), which are European weather satellites.

Aqua is an US earth observation satellite for observing, from space, various physical quantities (environmental data) relating to the circulation of water and energy and for integrally examining mutual interactions between the atmosphere, the ocean, and continents and effects thereof on changes in the earth system. Aqua is equipped with a MODIS sensor and observes the amount of chlorophyll using the MODIS sensor. Chlorophyll is a plant microorganism. Chlorophyll exists near the ocean surface of the earth and absorbs CO2by photosynthesis. The absorbance of CO2by chlorophyll influences the water temperature of the ocean surface and the amount of salt on the ocean surface.

Overview and Features of CO2Concentration Correcting Apparatus

The overview and features of the CO2concentration correcting apparatus according to the first embodiment will be explained below with reference toFIGS. 1 and 2.FIG. 1is a diagram for explaining the overview and features of the CO2concentration correcting apparatus according to the first embodiment.FIG. 2is a diagram explaining the overview of processes performed by the CO2concentration correcting apparatus.

As illustrated inFIG. 1, the overview of the CO2concentration correcting apparatus represented in the first embodiment is that data on the CO2concentration, which is observed by the GOSAT and OCO, is corrected by considering vegetation data, the distribution of the amount of photosynthesis by chlorophyll, and changes in the amount of solar radiation on the basis of CO2concentration data, the amount of solar radiation, vegetation data (vegetation index SR), which is the distribution of plants, and the chlorophyll concentration that are obtained by a plurality of observation satellites (GOSAT, OCO, MTSAT, NOAA satellite, and Aqua) through their observations.

Specifically, the observation satellites obtain a high-resolution solar radiation value, a vegetation index, and a chlorophyll distribution over a wide range, and yearly deviations of the CO2concentration are corrected (evaluation by combining physical quantities that are acquired from the observation satellites is performed) to obtain a CO2concentration distribution without the effects from yearly climate changes. As described above, the amount of CO2that is absorbed by plant photosynthesis and chlorophyll photosynthesis according to changes in the amount of solar radiation due to yearly variations in weather is not considered for the conventional data on CO2concentration on the earth. The main features of the first embodiment are that the CO2concentration is corrected in a manner that the CO2concentration, which is observed by the GOSAT, is acquired and variations in the amount of CO2, which is absorbed by the activities of vegetation, and variations in the amount of CO2, which is absorbed by the activities of chlorophyll according to changes in the amount of solar radiation, with changes in the amount of solar radiation are calculated.

Planting plants, which photosynthesize actively, in regions where the CO2concentration is high and the amount of solar radiation is large and supplying the sea with iron where the chlorophyll concentration is high are effective methods to reduce excessive CO2on the earth. To do so, it is necessary to acquire accurate values of the CO2concentration, and it is desirable that changes in the amount of solar radiation that differ yearly have no effect on the observed values.

Because the CO2concentration is increasing year by year, even if measured values from the GOSAT in the past three years are averaged, data that can be dealt with as a normal cannot be obtained. However, in the first embodiment, a CO2concentration value according to a normal solar radiation amount (climate value) can be calculated by calculating the CO2concentration (total CO2data D) obtained provided that no plants exist and by then incorporating the amount of photosynthesis that is calculated on the basis an amount of solar radiation, which is a normal (for example, a mean of the amount of solar radiation in the past three years), into the calculated CO2concentration.

A correcting process of the CO2concentration correcting apparatus according to the first embodiment will be explained below with reference toFIGS. 1 and 2. Specifically, first, as illustrated inFIGS. 1 and 2, observation data on the CO2concentration that is measured by the GOSAT and data on the CO2concentration distribution on the earth, which is estimated by the OCO, are acquired and the data is stored as CO2concentration data A (see (1) inFIGS. 1 and 2).

MTSAT observes the amount of solar radiation per hour (hourly) in a day. Solar radiation amount data is acquired from image data that represents the amount of solar radiation, which is observed by MTSAT, and the solar radiation amount data is stored (see (2) inFIGS. 1 and 2). The solar radiation amount data that is obtained by MTSAT through observations is image data that is obtained per hour in each predetermined region on the earth (each predetermined lattice).

The NOAA satellite obtains vegetation data on plants on the earth through observations. The vegetation data (vegetation index SR) is acquired, and the vegetation index SR is stored (see (3) inFIGS. 1 and 2). The vegetation data (the vegetation index SR) that is obtained by the NOAA satellite through observations is image data of a monthly mean that is acquired from each predetermined region on the earth (each predetermined lattice).

Aqua observes the amount of chlorophyll in the ocean. The observed amount of chlorophyll is acquired and stored (see (4) inFIGS. 1 and 2). Aqua observes the amount of chlorophyll twice a day. Data on chlorophyll that is observed by Aqua is image data of a monthly mean that is acquired from each predetermined region on the earth (each predetermined lattice).

The amount of CO2(NEP value) absorbed by photosynthesis according to the vegetation distribution of plants is calculated on the basis of the vegetation data (vegetation index SR), which is obtained by the NOAA satellite through observations, and hourly solar radiation amount data. The calculated NEP value is stored as a plant absorption amount B (see (5) inFIGS. 1 and 2). In other words, the NEP value concerning plants is a net ecosystem production (the amount of absorption of CO2concentration) based on the vegetation data, which is obtained from the hourly solar radiation amount data. Specifically, the NEP value concerning plants is a numerical value that represents how much CO2(gC) is absorbed in a predetermined region in a region of 1 m2) per month. For example, it is observed that, while the NEP value that is observed in forests in Hokkaido is close to 0 from October to April where the temperature is relatively low, it increases to 230 (gC/m2/month) in June.

The amount of absorbed CO2(NEP value) according to changes (transition) in chlorophyll living in the ocean is calculated on the basis of the amount of chlorophyll, which is obtained by Aqua through observations, and the hourly solar radiation amount data. The calculated NEP value is stored as a chlorophyll absorption amount C (see (6) inFIGS. 1 and 2). In other words, the NEP value concerning chlorophyll is the amount of absorption of CO2concentration according to the chlorophyll concentration distribution, which is obtained from data on the amount of solar radiation, which is the normal.

Furthermore, the monthly mean of hourly solar radiation amount at least in the past three years is calculated as a cumulative average solar radiation amount. The data on the calculated amount of solar radiation is stored as cumulative average solar radiation amount data (see (7) inFIGS. 1 and 2).

Total CO2data D is calculated from the CO2concentration on the earth (the CO2concentration data A) that is obtained by the GOSAT through observations, the plant absorption amount B due to photosynthesis according to the vegetation distribution of plants, which is an amount calculated on the basis of the vegetation data (the vegetation index SR) and the hourly solar radiation amount data, and the chlorophyll absorption amount C due to photosynthesis according to changes (transition) in the amount of chlorophyll, which is data calculated on the basis of the amount of chlorophyll and the hourly solar radiation amount data (see (8) inFIGS. 1 and 2). Specifically, the total CO2data D is obtained by adding up the CO2concentration data A, the plant absorption amount B, and the chlorophyll absorption amount C (A+B+C=D). By performing these processes with respect to the past one month, a state is assumed where plants and chlorophyll all disappeared one month before, and the CO2concentration in such a state is calculated.

In addition, photosynthesis amount distribution data is generated on the basis of the data on vegetation on the earth (the vegetation index SR) and the cumulative average solar radiation amount (the hourly mean solar radiation amount data), which is the hourly mean of the amount of solar radiation in a month. The generated photosynthesis amount distribution data is stored as global plant photosynthesis amount E concerning plants (see (9) inFIGS. 1 and 2). The global plant photosynthesis amount E concerning plants is data that is accumulated hourly in each predetermined region on the earth (each predetermined lattice) for a month.

Photosynthesis amount distribution data is generated on the basis of the amount of chlorophyll living in the ocean and the cumulative average solar radiation amount (hourly mean solar radiation amount data), which is the hourly mean of the amount of solar radiation in a month. The generated photosynthesis amount distribution data is stored as a global chlorophyll photosynthesis amount F concerning chlorophyll (see (10) inFIGS. 1 and 2). Like the global plant photosynthesis amount E, the global chlorophyll photosynthesis amount F is data that is accumulated hourly in each predetermined region the earth (each predetermined lattice) for a month.

Difference data obtained by subtracting the global plant photosynthesis amount E and the global chlorophyll photosynthesis amount F from the total CO2data D is calculated as CO2concentration G, which is a normal (D−E−F=G) (see (11) inFIGS. 1 and 2). In other words, the CO2concentration G, which is the normal, is calculated as the net CO2concentration on the earth. The CO2concentration, which is the normal, contains the value (280 ppmv) that can exist in nature. Therefore, by subtracting 280 ppmv from the CO2concentration amount G, which is the normal, a value is obtained as a reduction target CO2amount H. The reduction target CO2amount H serves as the amount of CO2that serves as a target for reduction by additional tree planting.

Accordingly, the CO2concentration to be reduced is obtained and the ideal vegetation distribution can be determined. Thus, vegetation schemes for CO2reduction can be embodied. In other words, an area where the reduction target CO2amount H is large is an area to which green campaigns are carried out using plants (tree planting) or an area where ocean environmental improvement is made. Green campaigns for tree-planting or ocean environment improvement to cancel the difference will be performed. Specifically, plants may be planted in regions where the amount of CO2is large. In the ocean, to increase the amount of chlorophyll that absorbs CO2by photosynthesis, iron particles may be dispersed over the sea surface by, for example, an aircraft after sufficient environmental assessment has been performed.

From the reduction target CO2amount H, prospective plants and trees that should be planted on the earth and the size and number of these plants and trees (per unit area) can be calculated by estimation in consideration of the seasons and regions.

Configuration of CO2Concentration Correcting Apparatus1

The configuration of the CO2concentration correcting apparatus1will be explained below with reference toFIG. 3.FIG. 3is a block diagram of the configuration of the CO2concentration correcting apparatus according to the first embodiment. As illustrated inFIG. 3, the CO2concentration correcting apparatus1includes an input-output I/F unit2, a storage unit10, a control unit20, and an input-output control unit30.

The input-output I/F unit2controls input and output of observation data obtained by the GOSAT, OCO, MTSAT, NOAA satellite, and Aqua through observations. The input-output control unit30controls data transfer between the input-output I/F unit2and the storage unit10and between the input-output I/F unit2and the control unit20.

The storage unit10stores various types of data that is obtained by a plurality of satellites (GOSAT, OCO, MTSAT, NOAA satellite, and Aqua) through observations and data and programs necessary for various processes performed by the control unit20. The storage unit10includes, particularly as those closely related to the present invention, a chlorophyll storage unit11, a vegetation index storage unit12, a solar radiation amount storage unit13, a CO2concentration storage unit14, a chlorophyll absorption amount storage unit15, a plant absorption amount storage unit16, a total CO2storage unit17, a global chlorophyll photosynthesis amount storage unit18, and a global plant photosynthesis amount storage unit19.

The control unit20includes an internal memory for storing control programs, such as an operation system (OS), programs that define various process procedures, and necessary data. The control unit20includes, particularly as those closely related to the present invention, a CO2calculating unit21(chlorophyll), a CO2calculating unit22(vegetation index), a solar radiation amount calculating unit23, a cumulative average solar radiation amount calculating unit23a, a total CO2concentration calculating unit24, a global chlorophyll photosynthesis amount calculating unit25, an global plant photosynthesis amount calculating unit26, a normal CO2concentration calculating unit27, and a display unit31.

The chlorophyll storage unit11acquires data on the amount of chlorophyll on the earth, which is observed by Aqua. The chlorophyll amount data is stored with respect to each predetermined region on the earth (each predetermined lattice).

The vegetation index storage unit12acquires the data on vegetation on the earth, which is observed by the NOAA satellite, (vegetation index SR) and stores the vegetation data. The vegetation data is stored with respect to each predetermined region on the earth (each predetermined lattice).

The solar radiation amount storage unit13acquires the data on the amount of solar radiation on the earth, which is observed by MTSAT, and stores the data. The solar radiation amount data is stored per hour with respect to each predetermined region on the earth (each predetermined lattice).FIG. 4is a diagram explaining the observation region of the GOSAT and MTSAT and the region of calculation of the amount of solar radiation. As illustrated inFIG. 4, the region surrounded by the large circle represents the observation region of MTSAT and represents an observation that is performed every 30 minutes. In addition, the shaded range represents the observation region of the GOSAT over a certain observation time period. The same point is observed once every three days. The GOSAT orbits the earth 14 times a day and observes the shaded range at 13:16 Japan local time.

In other words, as illustrated inFIG. 4, the data on the amount of solar radiation, which is observed by MTSAT, is image data that is acquired hourly in the region of 0.0125 of a lattice located between 60-degrees north latitude and 60-degrees south latitude (2400×2400 pixels). As illustrated inFIG. 4, the image data on the amount of solar radiation is data acquired at a time that is the same as the local time (13:16) of the observation by the GOSAT.

The CO2concentration storage unit14stores data on the CO2concentration that is observed by the GOSAT and OCO. The CO2concentration that is stored in the CO2concentration storage unit14is data that consists of a lattice resolution of about 80 km, which is obtained by the GOSAT through observations at the same point once every three days (seeFIG. 4).

The chlorophyll absorption amount storage unit15stores the amount of CO2(NEP value) concerning chlorophyll, which is CO2absorbed according to changes (transition) in chlorophyll, which is an amount calculated by the CO2calculating unit21on the basis of the amount of chlorophyll stored in the chlorophyll storage unit11and the solar radiation amount data (hourly solar radiation amount) stored in the solar radiation amount storage unit13.

The plant absorption amount storage unit16stores the amount of CO2(NEP value) concerning plants, which is CO2absorbed according to changes (transition) in the plant distribution, which is an amount calculated by the CO2calculating unit22on the basis of the vegetation index stored in the vegetation index storage unit12and the solar radiation amount data (hourly solar radiation amount) stored in the solar radiation amount storage unit13.

The total CO2storage unit17stores data calculated by the total CO2concentration calculating unit24on the basis of the CO2concentration data, which is stored in the CO2concentration storage unit14, the CO2absorption amount that changes according to the transition in the plant distribution, which is an amount stored in the plant absorption amount storage unit16, and the chlorophyll-related CO2absorption amount that changes according to the transition in the existence of chlorophyll, which is an amount stored in the chlorophyll absorption amount storage unit15. Specifically, the stored data is a value obtained by adding up the CO2concentration data, the CO2absorption amount based on the plant data, and the amount of CO2absorbed by chlorophyll.

The global chlorophyll photosynthesis amount storage unit18stores data that is calculated by the global chlorophyll photosynthesis amount calculating unit25on the basis of the amount of chlorophyll, which is stored in the chlorophyll storage unit11, and the amount of solar radiation, which is calculated by the cumulative average solar radiation amount calculating unit23a.

The global plant photosynthesis amount storage unit19stores data that is calculated by the global plant photosynthesis amount calculating unit26on the basis of the vegetation index, which is stored in the vegetation index storage unit12, and the amount of solar radiation, which is calculated by the cumulative average solar radiation amount calculating unit23a.

The CO2calculating unit21calculates the amount of CO2(NEP value) that is absorbed according to changes (transition) in chlorophyll on the basis of the amount of chlorophyll, which is stored in the chlorophyll storage unit11, and the hourly solar radiation amount data, which is stored in the solar radiation amount storage unit13.

Specifically, an ocean CO2partial pressure is calculated taking the ocean temperature of the ocean surface on the earth and the climate value of the surface salinity into consideration for the chlorophyll concentration, and thus the amount of CO2absorbed (NEP value of chlorophyll) according to changes in chlorophyll is calculated. Note that although the formula is omitted, the NEP value of chlorophyll can be calculated by multiplying the CO2partial pressure by the normal ratio of the hourly solar radiation amount data. The NEP value that is calculated by the CO2calculating unit21is stored in the chlorophyll absorption amount storage unit15.

The CO2calculating unit22calculates the CO2concentration according to plants. Specifically, the amount of CO2(NEP value) absorbed according to changes (transition) in plants is calculated on the basis of the plant data, which is stored in the vegetation index storage unit12, and the hourly solar radiation amount data, which is stored in the solar radiation amount storage unit13. The CO2calculating unit22calculates the amount of CO2(NEP value) absorbed by photosynthesis according to the vegetation distribution of plants on the basis of the vegetation index SR, which is obtained by the NOAA satellite through observations, and the hourly solar radiation amount data, which is stored in the solar radiation amount storage unit13.

In other words, observation for vegetation data (the vegetation index SR) by the NOAA satellite is performed twice a day. The vegetation data that is observed by the NOAA satellite is image data that is obtained in the region of each predetermined lattice. The vegetation index SR can be obtained on the basis of a reflectance (NIR) of an infrared sensor, which is mounted on the NOAA satellite, and a reflectance (VIS) of visible light (vegetation index SR=NIR/VIS).

The NEP value, which is used for the amount of absorbed CO2(balance) based on the vegetation index SR can be obtained as an approximate value using the vegetation index SR (simple ratio), the solar radiation normal ratio, and the constant a from the following Equation 1 where the solar radiation normal ratio is the ratio of the momentary value to the normal of the amount of solar radiation (average in one hour) and a is 25. The NEP value, which is calculated by the CO2calculating unit22, is stored in the plant absorbance amount storage unit16.
NEP=a(SR−1)×solar radiation normal ratio  (Equation 1)

The solar radiation amount calculating unit23acquires the amount of solar radiation, which is observed by MTSAT, to calculate hourly solar radiation amount data. The solar radiation amount data, which is calculated by the solar radiation amount calculating unit23, is stored in the solar radiation amount storage unit13.

The cumulative average solar radiation amount calculating unit23acalculates, as the cumulative average solar radiation amount, the hourly mean of the amount of solar radiation in a month in the past three years. The solar radiation amount data, which is calculated by the cumulative average solar radiation amount calculating unit23a, is stored in the solar radiation amount storage unit13.

The total CO2concentration calculating unit24adds up the CO2concentration data, which is stored in the CO2concentration storage unit14, the CO2absorption amount that changes according to transition in the distribution of plants and that is stored in the plant absorption amount storage unit16, and the CO2absorption amount that changes according to transition in the existence of chlorophyll and that is stored in the chlorophyll absorption amount storage unit15. The total CO2concentration, which is calculated by the total CO2concentration calculating unit24, is stored in the total CO2storage unit17.

The amount of absorbed CO2that changes according to the amount of solar radiation and the transition in the distribution of plants and the transition in the existence of chlorophyll are explained with reference toFIG. 5.

FIG. 5is a diagram explaining the relation between the time of observation by the GOSAT at predetermined lattice coordinates, the amount of solar radiation at the coordinates, and the amount of CO2absorbed by plants and chlorophyll. The solid line inFIG. 5represents a sunny day and a dashed line inFIG. 5represents a cloudy day. As illustrated inFIG. 5, the amount of CO2absorbed by plants and chlorophyll increases on a sunny day compared to a cloudy day and the amount of absorbed CO2increases around noon (12:00-13:00 hrs). As illustrated inFIG. 5, the amount of absorbed CO2(NEP value) corresponding to the amount of solar radiation in the shaded portion is calculated, and correcting by adding the NEP value to the data on the CO2concentration observed by the GOSAT is performed. Note that the amount of CO2absorbed by plants and chlorophyll is a value obtained by accumulation from a month before.

The global chlorophyll photosynthesis amount calculating unit25calculates the global chlorophyll photosynthesis amount on the basis of the amount of chlorophyll, which is stored in the chlorophyll storage unit11, and the amount of solar radiation, which is calculated by the cumulative average solar radiation amount calculating unit23a. Specifically, the global chlorophyll photosynthesis amount, which is calculated by the global chlorophyll photosynthesis amount calculating unit25, is calculated as chlorophyll-related photosynthesis amount distribution data from the solar radiation amount data (a mean in a month) obtained by averaging the amounts for a predetermined number of past years (at least three past years) and the latest vegetation data (a mean in a month). The chlorophyll-related photosynthesis amount distribution data, which is calculated by the global chlorophyll photosynthesis amount calculating unit25, is stored in the global chlorophyll photosynthesis amount storage unit18.

The global plant photosynthesis amount calculating unit26calculates the global plant photosynthesis amount from the vegetation data, which is stored in the vegetation index storage unit12, and the amount of solar radiation (the vegetation index SR), which is calculated by the cumulative average solar radiation amount calculating unit23a. Specifically, the global plant photosynthesis amount, which is calculated by the global plant photosynthesis amount calculating unit26, is calculated as plant-related photosynthesis amount distribution data from the solar radiation amount data (a mean in a month) obtained by averaging the amounts for a predetermined number of past years (three past years) and the latest chlorophyll concentration. The photosynthesis distribution data on plants, which is calculated by the global plant photosynthesis amount calculating unit26, is stored in the global plant photosynthesis amount storage unit19.

FIG. 6is an explanatory diagram representing the transition of CO2over time variations. Specifically, the line chart a inFIG. 6represents the yearly transition of CO2in a year where the amount of solar radiation from April to June, which is observed by the GOSAT, is larger than that in a normal year. As illustrated inFIG. 6, the amount of solar radiation increases from April to June and the CO2concentration decreases chronologically because of photosynthesis by plants and chlorophyll.

The line chart b represents the yearly transition of CO2that is obtained by correcting the line chart a using the normal solar radiation amount. As illustrated inFIG. 6, the CO2concentration slightly increases, compared to the CO2concentration in the line chart a, such that that CO2concentration accords not with the amount of solar radiation in the year with a large amount of solar radiation but to the normal solar radiation amount. The line chart c represents the yearly transition of CO2in the case where no plant and no chlorophyll exist on the earth. As illustrated in the line chart c, the CO2concentration increases as time progresses. The line chart d represents the transition in the CO2concentration that is corrected using the normal solar radiation amount in a year where the amount of solar radiation from April to June is smaller than that in a normal year.

The normal CO2concentration calculating unit27calculates the CO2concentration from the total CO2concentration, which is stored in the total CO2storage unit17, the amount of chlorophyll, which is stored in the global chlorophyll photosynthesis amount storage unit18, and the vegetation index, which is stored in the global plant photosynthesis amount storage unit19, and stored as a normal CO2concentration storage unit28.

The display unit31includes a display or a monitor that displays various types of information. For example, the display unit31displays observation data, which is obtained by each satellite, such as the GOSAT, MTSAT, NOAA satellite, and Aqua, through their observations with respect to each predetermined region on the earth (each predetermined lattice). The effects from the distribution of plants and of chlorophyll can be visually confirmed using the image data that is displayed on the display unit31. In addition, effects from green campaigns can be visually confirmed.

Overall Process Procedure of CO2Concentration Correcting Apparatus1

FIG. 7is a flowchart of an overall process procedure of the CO2concentration correcting apparatus1. Specifically, as the flowchart inFIG. 7illustrates, it is determined whether it is hourly calculation timing (per hour) of observation data from the observation satellites (step S1). When it is determined that it is hourly calculation timing (per hour) of the observation data from the observation satellites (YES at step S1), data obtained by each of the observation satellites (GOSAT, MTSAT, NOAA satellite, Aqua) through observation is acquired and a monthly mean chlorophyll amount and a vegetation index of plants, and an hourly solar radiation amount are calculated (step S2). Specifically, the chlorophyll amount, the plant data, and the solar radiation amount are observed respectively by Aqua, the NOAA satellite, and MTSAT and calculated. Subsequently, the hourly total CO2concentration is calculated (step S3).

In contrast, when it is determined that it is not hourly calculation timing by determination at step S1(NO at step S1), it is then determined whether one month has passed since a predetermined time (step S4). When one month has passed since the predetermined time (YES at step S4), hourly solar radiation amount average data is calculated (step S5), and the process goes back to step S1.

In contrast, when it is determined that one month has not passed since the predetermine time by determination at step S4, it is then determined whether it is monthly calculation timing (step S6). When it is determined that it is monthly calculation timing (YES at step S6) a monthly global chlorophyll photosynthesis amount F concerning chlorophyll and a global plant photosynthesis amount E concerning plants are calculated (step S7).

As described above, the global chlorophyll photosynthesis amount F is calculated on the basis of the amount of chlorophyll, which is stored in the chlorophyll storage unit11, and the amount of solar radiation, which is calculated by the cumulative average solar radiation amount calculating unit23a. The global plant photosynthesis amount E is calculated on the basis of the vegetation index SR, which is stored in the vegetation index storage unit12, and the amount of solar radiation, which is calculated by the cumulative average solar radiation amount calculating unit23a.

Subsequently, the amount of photosynthesis (the amount of CO2to be reduced) that should be increased as green campaigns is calculated on the basis of the global chlorophyll photosynthesis amount information and the global plant photosynthesis amount information that are calculated at step S7(step S8) and the process goes back to step S1. As described above, the CO2concentration G, which is the normal, is calculated by calculating difference data that is obtained by subtracting the global plant photosynthesis amount E and the global chlorophyll photosynthesis amount F from the total CO2data D.

As described above, the CO2concentration correcting apparatus1according to the present invention is configured to calculate an hourly CO2concentration, an amount of solar radiation, and plant-chlorophyll distribution information from predetermined satellites through observation, calculate the concentration of CO2absorbed by plants hourly, calculate a total CO2concentration by adding up the CO2concentration on the earth and the concentration of CO2that is absorbed by plant-chlorophyll, calculate, as a mean, a concentration of CO2that is absorbed according to changes in the distribution of the plant-chlorophyll on the basis of a monthly mean solar radiation amount and the plant-chlorophyll distribution information, and perform correction for calculating a normal CO2concentration by subtracting the mean CO2concentration from the total CO2concentration. This corrects bias errors of the CO2concentration due to yearly variations in the weather. Accordingly, a CO2concentration with small errors resulting from the yearly weather variations can be estimated, which results in effective green campaigns.

The distribution of CO2varies time to time because of the circulation of atmosphere. Provided that the source is almost the same, it can be assumed that the distribution of CO2is uniform in a time scale of about one month. Accordingly, monthly mean hourly distribution data can be generated to obtain spatio-temporally uniform data. The monthly mean shifted day by day may be generated every day to incorporate the latest data. It is desirable to use observation data that is not patio-temporally averaged for the CO2concentration that incorporates the NEP value, which is estimated from the hourly solar radiation amount data.