Application of Data

Prologue

How is the data obtained from the newly developed and installed equipment used in this project?

The air collected by the ASE is conveyed to NIES and then the concentration of each constituent and the ratio of stable isotopes is calculated. The ASE enables accurate analysis of atmospheric constituents because sophisticated analyzers is used in the lab . It, however, is conducted less frequently, approximately twice a month, due to its inherent observation cycle time from installation, removal, transportation of the equipment and measurement.

On the other hand, the CME, once installed on the airplane, performs in-situ measurements automatically and stores its result in the memory during the period from the installation to the removal of the equipment. This period is determined based on the standard gas consumption rate and deterioration of the dryer. Therefor, it becomes possible to obtain huge amount of data of up to approximately 1500 flights per year with five aircraft.
Specific applications of the data and time frame and method for disclosing the data is now under consideration. We will introduce some of them in this section.

　　

Significance of Data　

In recent years, many efforts have been made by researchers to predict the future of global warming. This is known as ‘climate change forecasting research’. To this end, the complete harmonization of the three parts is required, i.e. ‘observation’, ‘mathematical climate modeling’　and ‘computing capability’.

The mathematical climate model is one of the computer programs for time integrated calculation using several physical laws represented by mathematical equations such as fluid mechanics and thermodynamics in relation to the atmospheric and ocean circulation and phase transition of water.
It differs from the short term weather forecasts, since it requires a powerful super computing machine. It is necessary to simplify some factors, such as relatively less significant variations, so as to calculate the future climate more precisely.
Because of recent technological innovations of the computer, however, super computers such as "Earth Simulator" have become available. With these machine, previous climate models based on the fluid dynamics of the atmosphere and ocean have rapidly evolved into integrated earth system models including atmospheric chemical reaction and circulation process.

Among several elements, the concentration of CO₂ was given as a fixed external parameter due to its uniformity. To establish the more complex "state of the art"climate model, however, it is necessary to understand clearly how carbon, the element in carbon dioxide and methane, circulate between ocean, atmosphere and land (plants etc.). It is also necessary to integrate the accurately simulated "carbon cycle" into the model.

Global carbon cycle (Unit : Gt, Source UK MET office)		Integrated Climate Model for forecasting the future of global warming (Source : Frontier Research Center for Global Change)
Elucidation of carbon cycle and forecasting of global warming

To do this "observation", it is extremely important to recognize the worldwide variation of greenhouse gases, such as CO₂.
The mechanism of the circulation are analyzed using the general circulation model, which enables the force of emission and absorption to be quantified .

Observation of greenhouse gases commenced at Mauna Loa, Hawaii in 1958 and are currently conducted at more than 100 locations in the world.
Although observation using ships, aircraft and balloons to understand three dimensional variation have been recently conducted, primary observation platforms are constructed on the ground, and there are some areas such as Southeast Asia, South America, South Africa and Siberia which are known as "insufficient observation areas"due to their geographical restriction.


The data obtained by the automatic continuous CO₂ measuring equipment loaded on JAL airplanes will enhance the area of the observation network, especially the CO₂ vertical profile, because the equipment can measure the CO₂ concentration during the climb phase and descent phase of these airplanes.

　

Area of insufficient observation (green circled)

Accordingly, should the observation network using the aircraft be strengthened worldwide especially in these areas, it is expected that the accuracy of worldwide carbon exchange, and eventually global warming forecasts, will significantly be improved.

The aircraft equipped with newly developed equipment are operated primarily as regular international flights. Since it is anticipated that there will be an increase in frequency of flights over Southeast Asia, one of the insufficient observation areas in the world, the quantity of the observation data produced by the continuous measurement with the CME will also increase.

If similar observation are conducted all over the world, it is expected that the the results will contribute to the practical operation of Kyoto Protocol because the distribution of the CO₂ can be estimated with higher temporal and spatial resolution, which enables measurement of regional emissions.

It is also expected to verify the data obtained by Satellites such as GOSAT and OCO which measures column concentration of greenhouse gases between the Satellite and the ground. They are scheduled to be launched an 2008 in Japan and the USA.

　

Feature of CME & ASE　

On the basis of the observed data regarding the distribution of CO₂ concentration in the atmosphere, it is possible to discern which regions are releasing CO₂ and which regions are absorbing it.

This method, known as the　‘inverse problem’, is currently the focus of intense research across the world.
With the inverse problem, the spatial distribution of the CO₂ exchange(income and expense) is estimated using the super computer. This is done using the transport model, by inputting the CO₂ concentration distribution and mathematical calculation.
For error assessment and accuracy improvement, research of the model that compares the calculated solution against other transport models under the same conditions is essential. This ensures good quality and quantity of the ‘observed data of CO₂ concentration’.

Estimation of regional source and sink by inverse problem　（Source .：JMA）

　

To specify the source and sink of the CO₂ using the ‘inverse problem’, it will be especially important to utilize the vertical distribution data of the CO₂ concentration. From this point of view, the CME allows continuous data to be obtained while the airplane climbs and descends. This will provide very useful information.

In addition to CO₂, there are other important greenhouse gases such as methane and various kinds of halogen chemical compounds. Continuous observation of these is also important. Also, measurements of isotope mixing ratio of carbon and oxygen (¹³C/¹²C and ¹⁸O/¹⁶O) play a great role in estimating the source and sink of the CO₂.　 However, at this moment the technology to automatically and continually measure these gases and ratios have not been developed yet. 　

Therefore, the automatic continuous CO₂ measuring equipment is designed to measure the concentration of CO₂. Other greenhouse gases are analyzed using the air collected by the automatic air sampling equipment.

Benefits of conducting the analysis in the lab is that various types of highly accurate analyzers are available. Many types of gases can be analyzed and isotope ratios can be measured as well as the concentration. In this regard, the analysis conducted by the automatic air sampling equipment(ASE) is also important since it enables us to achieve comprehensive analysis.

Since variation of atmospheric constituents including greenhouse gases and climate change interact with each other and give feedback, research of the prediction for the variation of those elements are pursued.
In the previous observation project, only three constituents including CO₂, CH₄ and CO were analyzed from the sampled air obtained by the ASE.
Under the new observation project, in addition to those species, H₂, N₂O, SF₆ and stable isotopes ratio for CO₂, ¹²C/¹³C, ¹⁶O/¹⁸O will be analyzed.

Moreover, as an incidental benefit of using these two types of equipment, the CO₂ concentration measured by the CME can be compared to that of measured by the ASE, and the accuracy of each equipment can be confirmed.

Observed Data　

Since the ASE has a capability to sample the air at any 12 points, it becomes possible to operate more precisely than the previous timer control method. With tｈｅ CME, the observation starts after takeoff until just prior to landing. It is possible to measure the CO₂ concentration vertically around the origin and destination airport as well as the lateral distribution during cruise shown below.

Observation by the CME

1. Data obtained during trial observation

Examples of the results of the trial observation by 747-400 aircraft started in November 2005.

Fig. 1. Comparison between CME and ASE

Fig.1 shows superimposed CO₂ latitudinal concentration obtained from both CME and ASE during a flight from Sydney to Narita on December.
Measurements by the CME correspond with the ASE measurements with highly accurate analyzers under stabilized conditions in a laboratory.
Comparing to the ASE which is capable of sampling the air at 12 points maximum, it is possible to make a continuous measurement over the flight route and then more detailed data becomes available.

Fig.2 represents vertical profile of the CO₂ concentration measured by the CME at around Narita airport and at Jakarta, Indonesia.
It shows higher concentration near the ground surface at Narita compared with Jakarta. The fact that there is no major difference in vertical concetration near Jakarta suggests that air is relatively well-mixed in tropical areas.

　

Fig. 2. Vertical Profiles

Fig. 3 plots the concentrations of the constituents in the sampled air by the ASE during multiple fights. It shows SF₆, one of the greenhouse gases. Ratios of carbon isotope(¹²C/¹³C) and oxygen isotope (¹⁶O/¹⁸O) will be analyzed to distinguish the source of the CO₂ emission.

　

Fig. 3. Latitudinal distribution of each greenhouse gases obtained by the ASE

　

2.　Quality assessment of CO₂ concentration data

Data obtained in previous observation was compared to that of new observation, and was evaluated for CO₂ concentration as well for equipment comparison between ASE and CME.
Reservoir performance of the flasks affected by the equipment renewal, and the influence of the gas scale difference between MRI and NIES were carefully reviewed.

As for the reservoir performance, it was confirmed by multiple flask samplings that the variation of the CO₂ concentration two days after sampling was extremely small. Therefore, no compensation is necessary for elapsed time from the sampling to the measurement. Regarding the gas scale difference, it becomes possible to compensate the measured value due to its constant relationship with the concentration.

Based on five simultaneous observation of the CME and the ASE, both data corresponded by a margin of -0.2ppm to +0.2ppm. The variation of the CME data around the ASE sampling points is 0.1ppm to 0.2ppm. It is acceptable under the natural variation and accuracy of the equipments.

Extrapolation of the data from the last 12.5 years shows no significant problem involved in terms of the continuity from the previous observation conducted by the 747 classic airplane from April 1993 to November 2005.

3. Disclosure and provision of the data

It is necessary to disclose the data obtained from the equipments to domestic and international research communities as well as the public after thorough confirmation of its accuracy and quality. A time frame and method to adequately disclose and provide the data is under consideration.

Findings obtained from the data will be provided through JAL foundation news etc. and published on this web pages, based on suggestions from the advisory committee .

　

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