AAS01-P01

Japan Geoscience Union Meeting 2016

Proportion of atmospheric methane to carbon dioxide observed by GOSAT over biomass burning
regions in Africa*Sachiko Hayashida1, Okiko Ono1
1.Faculty of Science, Nara Women's University
Multi-species satellite measurements in important biomass burning regions are expected for better
understanding the partitioning of reduced gas production (van der Werf, 2010). In this study, we
utilized the data of atmospheric concentration of carbon dioxide (CO2) and methane (CH4) observedby Thermal And Near-infrared Sensor for carbon Observation (TANSO)-FTS onboard Greenhouse Gases
Observing Satellite (GOSAT) to derive the ratios of the two species over the active biomass burning
regions in Africa. Contribution of fire emission from Africa to the global carbon fire emissions isestimated as 52% by van der Werf (2010). It is well recognized that in Northern Hemisphere Africa(NHA), fires occur primarily in the Sahel between November and February. On the other hand, inSouthern Hemisphere Africa (SHA), fires are prominent primarily between June and October (e.g.,
Roberts, et al. 2009). We investigated the proportions of CH4 to CO2 focusing on regions andseasonality and found the proportion of CH4 to CO2 during the burning season over NHA is higher
than that in SHA. In addition to CH4 and CO2, we are going to show the results of combined analysis
with carbon monoxide (CO) observed by Measurements Of Pollution In The Troposphere (MOPITT), anddiscuss potential of satellite sensors to characterize biomass burning.
References
Roberts et al. (2009): Biogeosciences, 6, 849-866.
van der Werf et al. (2010): ACP, 10, 11707-11735.
Keywords: carbon cycle, biomass burning, GOSAT©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P01 -AAS01-P02

Japan Geoscience Union Meeting 2016

Relationships between CO2 flux estimated by inverse analysis and land surface elements inSouth America and Africa*Kazuo Mabuchi1, Hiroshi Takagi1, Shamil Maksyutov1
1.National Institute for Environmental Studies
Inverse analysis estimates the regional flux of greenhouse gases between the earth’s surface andthe atmosphere by using observed atmospheric concentration data that include satellite data. In
particular, this method is effective in estimating the flux in regions where observational flux
data are limited. However, inverse analysis is basically a mathematical optimization method.
Therefore, confirmation of the causal validity of the spatial and temporal changes in the estimatedflux is necessary. One confirmation method is validation of the relationship with physical andbiological observation data (analysis data) of confirmed accuracy. In this study, the features andvalidity of changes in the CO2 flux estimated by inverse analysis were verified by interrelation
analysis with changes in precipitation, short-wave radiation, surface temperature, and Normalized
Difference Vegetation Index (NDVI) in regions of South America and Africa where CO2 flux
observation data are limited. Sufficient accuracy of the land surface elements is required for the
analysis results to confirm the CO2 flux estimated by inverse analysis. An examination of thecorrelation of anomalies showed consistent relationships among the precipitation, short-wave
radiation, surface temperature, and NDVI data used in this study, which were created independently.
The relationships between change in the estimated CO2 flux and characteristic changes of the land
surface elements in South America and Africa were consistent in each region. This study confirmed
the physical and biological validity of the changes in the CO2 flux estimated by inverse analysis.
During the period of this study, the NDVI anomaly was influential in South America, and theprecipitation (soil wetness) anomaly was an essential factor in Africa for the CO2 flux anomaly.
The short-wave radiation anomaly was also influential in both South America and Africa. These
relationships are detected more clearly in the results of inverse analysis using both ground-based
CO2 concentration data and GOSAT satellite data than in the results using only ground-based CO2
concentration data. This demonstrates the usefulness of GOSAT data in regions with limited
atmospheric CO2 concentration data.
Keywords: inverse simulation analysis, CO2 flux, land surface element©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P02 -AAS01-P03

Japan Geoscience Union Meeting 2016

Analysis of methane concentration variation observed by GOSAT in Sichuan Basin, China andits relationship with local sources*XIUCHUN QIN1, Masahiro Kawasaki1, Masafumi Ohashi2, Tomoki Nakayama1, Yutaka Matsumi1, Liping Lei3,
Zhonghua He3, Zhaocheng Zeng4
1.Nagoya university Institute for Space-Earth Environmental Research, 2.Kagoshima University, 3.
Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, 4.The Chinese
University of Hong Kong
Atmospheric Methane (CH4) is one of the most important greenhouse gases, and the greenhouse effectgenerated by unit molecule of CH4 is about 23 times higher than that of atmospheric Carbon Dioxide(CO2). Therefore, it will be more effective to reduce the CH4 emissions to mitigate the potential
global warming than reducing CO2 emissions. The increase of global atmospheric CH4 concentration ismainly due to agricultural activities, in which irrigated rice paddy is one of the most importantsources. China is the world's largest rice producer, accounting for about 22% of the rice planting
area in the world and 37% of the global production. Therefore, studies of China's regional CH4emissions and its driving factors are of importance to understand the regional and global carbon
cycle and the changing climate. In this study, XCH4 observations from GOSAT, spanning from January2010 to December 2013, are analyzed to study the spatio-temporal variation of XCH4 in China and its
relationship with regional surface emissions. In further, we investigate the driving mechanism of
XCH4 spatio-temporal variations, especially for high XCH4 values shown over Sichuan Basin insouth-west China, by combining the emission mechanism of rice planting process, the meteorology
data, the surface emission data and the regional atmosphere dynamic transportation.
The results indicate that spatially the Sichuan Basin presents a higher XCH4 concentration thanother regions in China and is 17 ppb higher than the paddy area in the same latitude zone.
Seasonally, XCH4 in Sichuan Basin during rice harvest season is generally higher than that in early
cultivation period. However, comparing to paddy area in the same latitude zone, Sichuan Basin showsa relatively higher XCH4 value during the winter of noncultivation period when the emissions fromrice paddies are weak and surface air temperature is low. To further investigate the high XCH4
concentration during this low-emission period, we use the HYSPLIT model to simulate the atmosphere
dynamic transport process, and the result suggests that the typical closed topography of Sichuan
Basin, which may lead to CH4 accumulation and keep it from diffusion, is one possible reason forthe high XCH4 value in winter.
Our result from studying the CH4 variations in Sichuan Basin, especially the abnormal higher value
during winter, and their driving factors demonstrate a certain potential of using GOSAT-XCH4 forinvestigating the regional CH4 changes. This study presents preliminary results of CH4 in China,
and a further investigation of the CH4 in the basin is still necessary as more satellite
observations of CH4 with improving accuracy are available in the coming future to further study theCH4 variations and regional emissions.
[1]Xiuchun Qin, Liping Lei, Zhonghua He, Zhao-Cheng Zeng, Masahiro Kawasaki, Masafumi Ohashi, andYutaka Matsumi, “Preliminary Assessment of Methane Concentration Variation Observed by GOSAT in
China”, Advances in Meteorology,2015, DOI: 10.1155/2015/125059
Keywords: GOSAT, XCH4, paddy field emission, atmosphere transmission, topography©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P03 -AAS01-P04

Japan Geoscience Union Meeting 2016

Development of Carbon cycle analysis system using satellite data and LETKF*Takashi Maki1, Takashi Nakamura4, Tsuyoshi Thomas Sekiyama1, Takemasa Miyoshi2, Toshiki Iwasaki3
1.Meteorological Research Institute, 2.RIKEN, 3.Graduate School of Science, Tohoku University,
4.Japan Meteorological Agency
We have developed satellite data assimilation system using CO2 concentration data obtained fromsatellite measurements using an ensemble-based four-dimensional data assimilation system (LETKF).
An online atmospheric transport model (MJ98-CDTM) is employed in the data assimilation system tooptimize surface CO2 fluxes from satellite observations at spatial and temporal resolutions of 6days and 2.8°, respectively. The features of GOSAT TIR L2 Ver. 1.0 data are their larger data
number than that of SWIR L2 (about 10 times) and smaller standard deviation than their former
version (TIR L2 Ver. 0.01). We have tested 4 types of satellite bias correction methods (w/o bias
correction, monthly mean bias correction, all data bias correction and globally constant bias
correction) using independent CO2 concentration analysis (JMA CO2 distribution) in our data
assimilation system. Our results showed that estimated CO2 concentration and fluxes are
significantly sensitive to bias correction method. This means that we should carefully choose
satellite bias correction method. In addition, satellite data bias correction allows modifying
surface CO2 flux almost entire earth surface. In the future, our satellite bias correction concept
makes it possible to use multiple satellite observation data simultaneously in CO2 data
assimilation.
Keywords: Carbon Cycle, Data Assimilation, Satellite Observation©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P04 -AAS01-P05

Japan Geoscience Union Meeting 2016

Estimation of global surface fluxes of a greenhouse gas with LETKF data assimilation
system*Ryu Saito1, Prabir K Patra2, Tazu Saeki2, Kazuyuki Miyazaki2
1.KOKUSAI KOGYO CO., LTD, 2.JAMSTEC
We present global CO2 flux estimations using the local ensemble transform Kalman filter (LETKF)
system with the GOSAT obtained XCO2 and the WDCGG compiled CO2 concentration data. In the previous
study [Miyazaki et. al., 2011], a performance of the LETKF system was evaluated using GOSAT column
pseudo-data in reference and the other various types of CO2 concentration data. Here, we use the
GOSAT retrievals to estimate the flux with the 4-D data assimilation system.
The data assimilation system used in this study was developed by Miyazaki et al., 2011, on thebasis of the LETKF scheme [Miyoshi et al.]. A basic methodology of the LETKF follows the original
EnKF [Ott et al., 2004; Hunt et al., 2007].The covariance localization [Houtekamer and Mitchell,
2001] is used to remove long range spurious correlations. The state vector augmentation method[Anderson, 2001; Aksoy et al., 2006; Tong and Xue, 2008] has been applied to simultaneously
estimate the atmospheric CO2 concentration as model states together with the surface CO2 flux as
uncertain model parameters. The surface fluxes at every model grid points are analyzed with 4-daily
assimilation window during 2012 year. The ensemble size is hundreds. The transport model is coupledwith the Center for Climate System Research/National Institute for Environmental Studies/Frontier
Research Center for Global Change (CCSR/NIES/FRCGC) atmospheric general circulation model (AGCM)
version 5.7b [Numaguti et al., 1995]. The model spatial resolutions are horizontally T42 truncation(approximately 2.8 degree) and vertically 32 levels up to 7 hPa. The surface CO2 concentrations
used in this study are obtained with the flask sampling data observed at sites in the surface
network, which is archived at the WDCGG, and the XCO2 concentrations are retrieved from GOSAT
soundings using the RemoTec algorithm [Butz et al., 2009]. These observational data assimilate into
the transport model. The LETKF system performance is evaluated by error reduction ratio of theposterior to prior ensemble fluxes.
We show analysis results that are the error reduction ration depending on various types of theobservational data and seasonal variability of the optimized fluxes over aggregated land scale.
Acknowledgements. The authors thank the RemoTeC Proxy products retrieved from GOSAT TANSO-FTS SWIR
spectra using the RemoTeC algorithm that is being jointly developed at SRON Netherlands Institutefor Space Research and the Karlsruhe Institute for Technology (KIT).
Keywords: Carbon cycling, Ggreenhouse gas, Data assimilation, LETKF©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P05 -AAS01-P06

Japan Geoscience Union Meeting 2016

Application of Inversion Technique to Quick Update of Anthropogenic NOx emission over East
Asia with Satellite Observations and Chemical Transport Model*Keiya Yumimoto1, Itsushi Uno2, Syuichi Itahashi3, Kazuyuki Miyazaki4
1.Meteorological Research Institute, 2.Research Institute for Applied Mechanics, Kyushu University,
3.Central Research Institute of Electric Power Industry, 4.Japan Agency for Marine-Earth Scienceand Technology
We developed a quick update system for an emission inventory with an inversion technique, andextended NOx emission in Regional Emission inventory in the ASia version 2.1 (REAS 2.1) through2009–May 2013 with satellite-observed tropospheric NO2 vertical column densities (VCDs) and achemical transport model. The observed NO2 VCDs over the eastern Chinese region exhibited a drastic
inter-annual variation over the eastern Chinese region due to the socioeconomic condition. During
2008–2009, the growing of the NO2 VCD became sluggish because of pollutant controls by the 2008
Beijing Olympic game and the global depression, but revived in 2010 with a growth rate of
37.3%/year. The modeled NO2 VCD with the updated emission successfully followed the inter-annual
variation, and reproduced the observed seasonal cycle in which summer and winter have the seasonalbottom and peak, respectively. We estimated the updated Chinese anthropogenic NOx emissions during
2009–2012 to be 25.7, 27.3, 28.2, 28.4 Tg/year; they fell within the range of the various estimatesin the literatures. An annual growth rate during 2009–2012 and 2005–2012 was estimated to be
3.5%/year (0.9 Tg/year) and 5.3%/year (1.1 Tg/year), respectively. The system has the capability of
updating NOx emission in near real-time (NRT) for air qualtiy forecasting. Figure shows annual
anthropogenic NOx emission from China. Numbers in the panels represent annual Chinese anthropogenic
NOx emission. Other estimates of Chinese NOx emission are also shown by symbols.
Keywords: Inversion, Emission inventory, Chemical transport model, Satellite observation, NOxemission©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P06 -AAS01-P07

Japan Geoscience Union Meeting 2016

Characteristics of Version 1.0 CO2 data retrieved from TIR band of GOSAT/TANSO-FTS*Naoko Saitoh1, Shuhei Kimoto1, Ryo Sugimura1, Ryoichi Imasu2, Kei Shiomi3, Akihiko Kuze3, Toshinobu
Machida4, Yousuke Sawa5, Hidekazu Matsueda5
1.Center for Environmental Remote Sensing, Chiba University, 2.Atmosphere and Ocean ResearchInstitute, University of Tokyo, 3.Japan Aerospace Exploration Agency, 4.National Institute forEnvironmental Studies, 5.Meteorological Research InstituteGreenhouse Gases Observing Satellite (GOSAT) was launched on 23 January 2009, and has continued tomake global observations of greenhouse gases, including both nadir and off-nadir measurements, formore than seven years since its launch. Carbon dioxide (CO2) concentrations in several atmosphericlayers can be retrieved from radiance spectra of the thermal infrared (TIR) band of Thermal and
Near-infrared Sensor for Carbon Observation Fourier Transform Spectrometer (TANSO-FTS) on board the
GOSAT. We have analyzed the latest released version of the TIR Level 2 (L2) CO2 product (Version
1.0). We compared TANSO-FTS TIR V1.0 CO2 data and CO2 data obtained in the Comprehensive
Observation Network for TRace gases by AIrLiner (CONTRAIL) project. The comparisons over several
airports showed that the TIR V1.0 CO2 data had a 1-2% negative bias in the middle troposphere; themagnitude of the bias varied seasonally and regionally. The comparisons in the upper troposphereand lower stratosphere (UTLS), where the TIR band of TANSO-FTS is most sensitive to CO2concentrations, showed that the averages of the TIR upper atmospheric CO2 data agreed well with theaverages of the data obtained by the CONTRAIL Continuous CO2 Measuring Experiment (CME) within 0.1%
and 0.5% for all of the seasons in the Southern and Northern Hemisphere, respectively. The
magnitude of bias in the TIR upper atmospheric CO2 data did not have a clear longitudinal
dependence. The comparison results for flights in northern low and middle latitudes showed that theagreement between TIR and CONTRAIL CO2 data in the upper troposphere was worse in the spring andsummer than in the fall and winter. The negative bias in northern middle latitudes made the maximumof TIR CO2 concentrations lower than that of CONTRAIL CO2 concentrations, which leads tounderestimate the amplitude of CO2 seasonal variation. CO2 growth rate estimated from the TIR UTLS
CO2 data from 2010 to 2012 was slightly lower (-0.6 ppm) than that from the CONTRAIL level flightdata during the same period, which increases the differences between TIR and CONTRAIL CO2
concentrations in UTLS.
Keywords: satellite remote sensing, retrieval algorithm, validation analysis, CO2©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P07 -AAS01-P08

Japan Geoscience Union Meeting 2016

Validation of GOSAT SWIR XCO2 and XCH4 retrieved by PPDF-S method*Chisa Iwasaki1, Sachiko Hayashida2, Ryoichi Imasu1, Tatsuya Yokota3, Isamu Morino3, Yukio Yoshida3
1.Atmosphere and Ocean Research Institute, The University of Tokyo, 2.Nara Women's University,
3.National Institute for Environmental Studies
We focused on column averaged dry air mole fraction of atmospheric CO2 and CH4 (XCO2 and XCH4,
respectively) retrievals from Greenhouse gases Observing Satellite (GOSAT) measurements through thephoton path length probability density function (PPDF-S) based retrieval method that simultaneously
retrieves target gas abundance and PPDF parameters. This method is used for an effective retrieval
algorithm even under high concentration of clouds and aerosols. First, we validated PPDF-S XCO2 and
XCH4 retrievals by comparing them with ground-based observations provided by the Total Carbon
Column Observing Network (TCCON) from June 2009 to May 2014. For comparison, we also validate
retrievals through another algorithm using full physics (FP)-based retrieval method. PPDF-S and FP
retrieval methods are different in way to account for light scattering effect. All these XCO2 and
XCH4 retrievals are provided by the National Institute for Environmental Studies (NIES). PPDF-S
retrievals have positive biases (0.47 ±2.11 ppm for XCO2 and 0.76 ±15.49 ppb for XCH4), on theother hand, FP retrievals have negative biases (-0.28 ±2.34 ppm for XCO2 and -2.16 ±13.26 ppb for
XCH4). Next, we compare global maps of XCO2 and XCH4 mean value, standard deviation and number ofdata between PPDF-S and FP retrievals. Over the ocean, PPDF-S method can retrieve large number ofdata whose standard deviation is larger than FP method. These PPDF-S retrievals over the ocean
include data which are eliminated in post-screening process for FP method to exclude data that arestrongly affected by clouds and aerosol.
Keywords: GOSAT, retrieval, carbon dioxide, methane©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P08 -AAS01-P09

Japan Geoscience Union Meeting 2016

Global carbon budget estimation based on atmospheric oxygen and carbon dioxide observation
during recent 15-year period*Yasunori Tohjima1, Mukai Hitoshi1, Toshinobu Machida1, Shin-ichiro Nakaoka1
1.National Institute for Environmental Studies
Time series of atmospheric O2/N2 ratio and CO2 mixing ratio of flask samples taken from NIES’s flask
sampling network are presented. The network includes ground sites, Hateruma Island (lat 24°03'N,
long 123°48'E) and Cape Ochi-ishi (lat 43°10'N, long 145°30'E), and cargo ships regularly sailingin the Pacific region. The air samples collected in Pyrex glass flasks were sent back to ourlaboratory and the O2/N2 ratio and CO2 mixing ratio were analyzed by using a GC/TCD and NDIR
analyzers. Taking into account the global mass balances of atmospheric CO2 and O2, we estimate theglobal carbon sequestration rates of the ocean and land biosphere for the recent 15-year period. In
this carbon budget calculation, we use the secular changes in the atmospheric O2 and CO2 burdens
based on our flask observations and the fossil fuel-derived CO2 emissions based on energy
statistics. We also adopt the ocean O2 outgassing fluxes (~0.5 PgC/yr), which is estimated fromsecular changes in the ocean heat content (0-2000m) and an estimated O2-to-heat flux ratio. For
example, the oceanic and land biotic carbon sequestration rates for the 15-year period (1999-2014)
calculated from the observation at Hateruma Island are 2.4±0.7 Pg-C yr-1 and 1.5±0.8 Pg-C yr-1,
respectively. In the presentation, we also examine the temporal changes in the global carbon
budgets and compare our estimations with the other reported carbon budget estimations.
Keywords: global carbon budget, oxygen, carbon dioxide©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P09 -AAS01-P10

Japan Geoscience Union Meeting 2016

Achievements and Future Visions: Monitoring Carbon Cycle Change using an Integrated
Observation, Modeling and Analysis System*Nobuko Saigusa1, Toshinobu Machida1, Prabir Patra2, Yosuke Niwa3, Kazuhito Ichii2
1.National Institute for Environmental Studies, 2.Japan Agency for Marine-Earth Science andTechnology, 3.Meteorological Research InstituteWe are developing an integrated carbon observation and analysis system based on satellite, airborne
and ground-based observations, and atmospheric and terrestrial carbon cycle models. Aircraft
observations of atmospheric greenhouse gases (GHGs) are strengthened based on the “Comprehensive
Observation Network for TRace gases by AIrLiner (CONTRAIL)” project. Atmospheric transportmodeling, inverse modeling, and assimilation methods are being developed and improved for better
utilization of observational data from the Asia-Pacific region. Global and regional surface fluxes
are estimated by both "top-down” approach using inverse models and "bottom-up” approach using
surface flux observation network data (e.g. AsiaFlux) and upscaling with terrestrial ecosystemmodels.
We will present current progress for better constraints of global, continental, and regional carbon
budgets, and detection of carbon cycle change particularly in the Asia-Pacific. We also would liketo raise following questions and discuss how to solve them in the next steps.
1) How can the current capabilities of top-down and bottom-up approaches contribute to reduce
uncertainties in the estimates of large anthropogenic emissions? (e.g. fuel use, land use changes,
and rapid urbanization)2) What are the key target regions or events in the Asia-Pacific that we need to focus on? (e.g. El
Niño-induced droughts, extreme forest fires in Southeast Asia, and peat degradations in tropicaland boreal regions)3) How should the current capabilities of observation, modeling and analysis systems be integrated
into an operational system for long-term monitoring of changes in regional, continental, and global
GHGs budgets?
4) What are the urgent requirements to realize such system? (e.g. strategies of more intensive
observations in targeted area, and a platform for multi-model ensemble)5) How can we provide scientific knowledge and data timely for evaluating mitigation and adaptation
policies?
Keywords: Carbon Cycle, Integrated Observation and Analysis System, Asia-Pacific©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P10 -AAS01-P11

Japan Geoscience Union Meeting 2016

Synthesis of top-down and bottom-up estimations of terrestrial CO2 budget in Asia
*Kazuhito Ichii1,2, Masayuki Kondo1, Prabir Patra1, Tazu Saeki1, Takashi Maki3, Takashi Nakamura4,
Yosuke Niwa3, Masahito Ueyama5, Masato Hayashi2, Habura Borjigin2, Yuji Yanagi1, Nobuko Saigusa2,
Asia-MIP Group
1.Japan Agency for Marine-Earth Science and Technology, 2.National Institute for Environmental
Studies, 3.Meteorological Research Institute, 4.Japan Meteorological Agency, 5.Osaka Prefecture
University
In the framework of Environment Research and Technology Development Funds (2-1401) from the
Ministry of the Environment of Japan, we initiated synthesis analysis toward better estimations andunderstandings of terrestrial CO2 budget in Asia. We used multiple different data products such asatmospheric inverse analysis (top-down estimation), terrestrial ecosystem models, remote sensing
data, and data-driven models (bottom-up estimation). Our analysis focuses on (1) inter-decadalchanges in terrestrial CO2 fluxes at continental scales (Asia and Siberia), (2) testing consistencyof terrestrial sink magnitude between top-down and bottom-up estimations in Asia, and (3) detection
and analysis of ‘hotspot’ of terrestrial CO2 budget changes in Siberia and tropical Asia. We willshow these progresses, and discuss future direction of these studies.
Acknowledgement
This study was supported by the Environment Research and Technology Development Funds (2-1401) from
the Ministry of the Environment of Japan, and the JSPS KAKENHI (grant No. 25281003).
Keywords: Terrestrial, Synthesis, Carbon Dioxide©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P11 -AAS01-P12

Japan Geoscience Union Meeting 2016

The potential of spaceborne LiDAR for precise forest resources observation*Masato Hayashi1, Nobuko Saigusa1, Yoshiki Yamagata1
1.National Institute for Environmental Studies
Satellite remote-sensing is suitable for a large scale observation of forests, and spaceborne lightdetection and ranging (LiDAR) is a novel sensor that can be used for accurate measurement.
Spaceborne LiDAR is an active sensor to transmit laser pulses, and it records the changes in returnlaser energy intensity as a waveform, and the waveform contained information on the verticalstructure of forests. The only spaceborne LiDAR so far has been the Ice Cloud and land Elevation
Satellite (ICESat)/ Geoscience Laser Altimeter System (GLAS), operated by NASA from 2003 to 2009.
Many previous studies have applied GLAS data to forest observation, and they mostly estimated two
essential parameters of forest resources: canopy height and aboveground biomass. We also applied
ICESat/GLAS spaceborne LiDAR data to three forested areas: Hokkaido Island in Japan (cool-temperate
forest), Borneo Island (tropical forest), and Siberia (boreal forest). As a result, we revealed the
distribution of canopy height and aboveground biomass in the study areas. Furthermore, we
implemented the following: (1) quantitative estimates of canopy height change according to typhoon
disturbance in Hokkaido, (2) estimation of yearly forest loss rate in Borneo, and (3) hot spots
detection of forest change in Siberia. In this way, spaceborne LiDAR enables us to observe forest
resources accurately at each footprint point. However, an analysis combined with the other imagery
data should be needed for entirely forest monioring, and the methodology has been studied in recent
years. There are some plans of spaceborne LiDARs launched within a few years, and they will play animportant role in global forest resources monitoring in the future.
Keywords: Canopy height, Forest biomass, Spaceborne LiDAR, ICESat/GLAS©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P12 -AAS01-P13

Japan Geoscience Union Meeting 2016

Development of a low-cost in-situ methane observation system and results of fieldobservation at a paddy field in India*Masaya Izuhara1, Takehiro Hidemori1, Masahiro Kawasaki1, Tomoki Nakayama1, Yutaka Matsumi1, Hiroshi
Sasago1, Yukio Terao2, Shohei Nomura2, Toshinobu Machida2, Wataru Takeuchi3, Minaco Adachi4, Ryoichi
Imasu5, Surendra Kumar Dhaka6, Jagmohan Singh6, Kenshi Takahashi7
1.Institute for Space-Earth Environmental Research, Nagoya University, 2.National Institute forEnvironmental Studies, 3.Institute for Industrial Science, the University of Tokyo, 4.Graduate
School of Life and Environmental Sciences, University of Tsukuba, 5.Atmosphere and Ocean ResearchInstitute, the University of Tokyo, 6.Rajdhani College, University of Delhi, 7.Research Institutefor Sustainable Humanosphere, Kyoto University
Methane (CH4) is the second most prevalent greenhouse gas next to carbon dioxide (CO2). The
atmospheric concentration of methane tends to increase year by year, and it is important to obtain
detail information on the source of methane and seasonal variation of its concentration. Since
there are many unclear points about the regional differences and seasonal variations of the methane
concentration, further ground-based observations are needed to investigate them in detail. Previous
studies suggest that the emissions of methane from farmlands in Southeast and South Asia havesignificant contribution to the methane concentrations. But, there are many difficulties to conduct
observations in such farmlands. At the paddy field in north India where we plan to observe methane,electric power are available for only 2-3 hours a day at night and the duration of power supply is
not stable. In addition, the place where we can set the measurement instrument is nothing but abarn in the farmland, and we must manage to prevent bad influences on instruments by rain, dust,bugs, and rats. Thus, it is difficult to use existing commercial instruments, which are typicallyoperated in a clean laboratory. Therefore, we developed a low-cost measurement system of methane touse at rural and remote area. Moreover, we have conducted the methane measurement using thedeveloped system at the paddy field in India.
In this study, we used LaserMethane(ANRITSU Co. Ltd.) to measure the atmospheric concentrations ofmethane. LaserMethane is the portable instrument with low electricity consumption, which canmeasure methane concentrations in real time. LaserMethane is an open-path laser spectroscopic
instrument which can measure methane selectively by tunable diode laser absorption spectroscopy. We
developed a power supply, a data logging, and a remote control equipment for continuous operationof LaserMethane at remote area. We have conducted the methane observation at Sonipat, Haryana in
India which is located at north of Delhi since the end of 2014 using the developed system. Alongwith LaserMethane, we have also obtained methane concentrations from the off-line analyses ofambient air, which have been sampled typically once a week, using gas chromatography. The
concentration data of LaserMethane are calibrated by the air sampling data and meteorological data.
In this presentation, we will present the introduction of the developed system and the measurement
results which were obtained in 2015 at the paddy field in Sonipat, India. It showed that theconcentrations of methane increased in monsoon season and winter. This characteristic enhancementof methane concentrations observed in monsoon season is considered to be due to the large methane
emission from paddy field during rice cultivation. In addition, the real-time measurements
indicated that the large variation of methane concentrations between day and night often appeared.
We will also discuss the sources of the observed seasonal and diurnal variations.
Reference
Matsumi et al., Measuring methane with a simple open-path gas sensor, SPIE Newsroom, doi:
101117/2.1201601.006283, 2016©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P13 -AAS01-P13

Japan Geoscience Union Meeting 2016

http://spie.org/newsroom/technical-articles/6283-measuring-methane-with-a-simple-open-path-gas-sensorKeywords: in-situ methane measurement system, field observation in India, rice paddy field©2016. Japan Geoscience Union. All Right Reserved.

- AAS01-P13 -AAS01-P14

Japan Geoscience Union Meeting 2016

Annual variaiton of soil respiriration in subtropical afforetation forest in Taiwan*PoNeng Chiang1, Jui-Chu Yu1, Yen-Jen Lai1
1.Experimental Forest, National Taiwan University
Global forests contain 69% of total carbon stored in forest soil and litter. But the carbon storage
ability and release rate of warming gases of forest soil also affect global climate change. Soil
carbon cycling processes are paid much attention by ecological scientists and policy makers becauseof the possibility of carbon being stored in soil via land use management. Soil respiration
contributed large part of terrestrial carbon flux, but the relationship of soil respiration andclimate change was still obscurity. Most of soil respiration researches focus on template andtropical area, little was known that in subtropical area. Afforestation is one of solutions to
mitigate CO2 increase and to sequestrate CO2 in tree and soil. Therefore, the objective of thisstudy is to clarify the relationship of tree species and soil respiration distribution in
subtropical broad-leaves plantation in southern Taiwan. The research site located on southern
Taiwan was sugarcane farm before 2002. The sugarcane was removed and fourteen broadleaved tree
species were planted in 2002-2005. Sixteen plots (250m*250m) were set on 1 km2 area, each plot
contained 4 subplots (170m2). The forest biomass (i.e. tree height, DBH) understory biomass,
litter, and soil C were measured and analyzed at 2011 to 2015. Soil respiration measurement was
sampled in each subplot in each month. The soil belongs to Entisol with over 60% of sandstone. The
soil pH is 5.5 with low base cations because of high sand percentage. Soil carbon storage showedsignificantly negative relationship with soil bulk density (p<0.001) in research site. The
differences of distribution of live tree C pool among 16 plots were affected by growth
characteristic of tree species. Data showed that the accumulation amount of litterfall was highest
in December to February and lowest in June. Different tree species planted in 16 plots, resulting
in high spatial variation of litterfall amount. It also affected total amount of litterfall
temporal variation. Soil respiration was related with season variation in research site. Soil
temperature and soil respiration showed highly spatial variation in 16 plots. Soil temperature
showed significantly exponential related with soil respiration in research site (p<0.001). Annual
soil temperature was decrease with tree age increasing in this 5 years. Annual soil respiration was
showed decrease with tree age increasing. However, soil respiration showed significantly negative
relationship with total amount of litterfall (p<0.001), suggesting that the tree was still young
and did not reach crown closure.
Keywords: Soil respiration, Plantation, Spatial Variation©2016. Japan Geoscience Union. All Right Reserved.

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Japan Geoscience Union Meeting 2016

Spatial and temporal seasonal variation of CO2 efflux from the soil surface in the boreal
forests in Central Siberia*Anastasia Vladimirovna Makhnykina1, Anatoly Stanislavovich Prokushkin2, Sergey Vladimirovich
Verkhovets1, Nataly Nikolaevna Koshurnikova1
1.Siberian Federal University, 2.V.N. Sukachev Institute of forest of Siberian Branch RAS
In boreal forest ecosystems, soil CO2 flux may account for 40–80 % of the total CO2 release inforest ecosystems [4], and it is the main pathway of transferring carbon from terrestrial
ecosystems to the atmosphere. The amount of CO2 released to the atmosphere through soil respiration
is ten times greater than that resulting from the burning of fossil fuels [3]. Taking into accountthe considerable amounts of C stored in boreal soils [1] even small changes in soil respiration may
cause great fluctuation in atmospheric CO2 concentrations. Therefore, better understanding of soil
respiration dynamics in diverse boreal forests is essential for understanding the global carbon
balance [2].
The objectives of the present study are: (a) to study the dynamic changes in soil CO2 efflux fromthe soil surface during frost-free season; (b) to identify the impact of meteorological variables(factors) on soil CO2 efflux. The research was conducted in the boreal forests in Central Siberia(60°N, 90°E), Russia. Sample plots were represented by the lichen pine forest, moss pine forest,
mixed forest and a plot with mineral sandy soil without a plant cover. We used the automated soil
CO2 flux system based on the infrared gas analyzer –LI-8100 (Li-cor Biogeosciences Inc., USA) for
measuring the soil efflux. Soil temperature was measured next to each collar at the time of the CO2
efflux measurement with Soil Temperature Probe Type E (Omega, USA) in three depths –5, 10, 15 cm.
Volumetric soil moisture was measured with Theta Probe Model ML2 (Delta T Devices Ltd., UK).
The presence and type of ground cover substantially affects the value of soil respiration fluxes.
In 2015, the flow of carbon dioxide from the soil surface averaged 5.4 ±2.3 μmol CO2 m-2 s-1. The
lowest soil respiration for forest areas was observed in the moss pine forest (1.14 μmol CO2 m-2 s-1). The lichen pine forest had the intermediate values (mean and SD) of soil respiration. A sandy
soil plot without a plant cover demonstrated the lowest soil respiration (0.12 μmol CO2 m-2 s-1).
The maximum soil respiration values and seasonal fluctuations were obtained in the mixed forest(29.62 μmol CO2 m-2 s-1).
The correlation analysis of dependence between soil temperature, soil moisture and soil CO2 efflux
showed that an increase of temperature and soil moisture at the beginning of the growing season(June) leads to inhibition of soil respiration processes. At the end of the growing season(September), we recorded a reduction in the impact of two climate factors (soil temperature andmoisture) on soil respiration intensity. Nevertheless, the soil temperature appears to be the major
driver controlling the soil CO2 efflux during the frost-free season in analyzed Siberian boreal
forests.
Literature:
1. Niinistö S. M., Kellomäki S., Silvola J. Seasonality in a boreal forest ecosystem affects theuse of soil temperature and moisture as predictors of soil CO2 efflux. Biogeosciences, 8:3169–3186. 2011.
2. Raich J.W., Potter C.S. Global patterns of carbon dioxide emissions from soils. Global
Biogeochemical Cycles, 9: 23–36. 1995.
3. Sun L., Hu T., Kim J. H., Guo F., Song H., Lv X., Hu H. The effect of fire disturbance on
short-term soil respiration in typical forest of Greater Xing’an Range, China. Journal of Forestry
Research 25: 613-620. 2014.

©2016. Japan Geoscience Union. All Right Reserved.

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Japan Geoscience Union Meeting 2016

4. Yuste J.C., Nagy M., Janssens I.A., Carrara A., Ceulemans R. Soil respiration in a mixed
temperate forest and its contribution to total ecosystem respiration. Tree Physiol 25: 609–619.
2005.
Keywords: soil carbon efflux, boreal forest, Siberian forest, soil respiration, soil temperature,soil moisture©2016. Japan Geoscience Union. All Right Reserved.

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