Conference Agenda

2018 Dragon 4 Symposium

Session
WS#1 ID.32301: GHGs from Space
Time:
Wednesday, 20/Jun/2018:
10:30am - 12:00pm

Session Chair: Prof. Ronald Johannes van der A
Session Chair: Prof. Yi Liu
Workshop: Atmosphere, Climate & Carbon Cycle
XUST Main Building - Conference Room

Presentations
Oral
ID: 289 / WS#1 ID.32301: 1
Oral Presentation
Atmosphere, Climate & Carbon: 32301 - Monitoring Greenhouse Gases from Space

TanSat new achievements

Yi Liu1, Dongxu Yang1, Hartmut Boesch2, Johanna Tamminen3, Liang Feng4

1Institute of Atmospheric Physics, Chinese Academy of Sciences, China, People's Republic of; 2University of Leicester, United Kingdom; 3Finnish Meteorological Institute, Finland; 4University of Edinburgh, United Kingdom

Chinese carbon dioxide observation satellite (TanSat) launched in 22 Dec 2016, after on-broad test and calibration, the TanSat starts to record the back-scattered sunlight spectrum from scientific earth observation and produced first XCO2 data from February to July in 2017.

The optimal estimation theory was involved in TanSat XCO2 retrieval algorithm in a full physics way with simulation of the radiance transfer in atmosphere. Gas absorption, aerosol and cirrus scattering and surface reflectance associate with wavelength dispersion have been considered in inversion for better correction the interference errors to XCO2. In this presentation, I will show the preliminary results of XCO2 retrieved from TanSat measurements, and inter-compared with OCO-2 results in an overlap footprint measurement over north Australia. Validation study with TCCON measurements indicate a better than 4 ppm with 8 stations. The first global XCO2 map has represented a milestone in Chinese GHGs satellite. TanSat will release level 2 and higher level products to support carbon emission estimations and climate change studies.


Oral
ID: 230 / WS#1 ID.32301: 2
Oral Presentation
Atmosphere, Climate & Carbon: 32301 - Monitoring Greenhouse Gases from Space

Using Satellites to Observe the Greenhouse Gases Exchange over China

Hartmut Boesch1, Nikoleta Kalaitzi1, Robert Parker1, Jasdeep Anand1, Peter Somkuti1, Liang Feng2, Paul Palmer2, Yi Liu3, Dongxu Yang3, Zhaonan Cai3, Wang Xi3, Xiangjun Tian3

1Earth Observations Science Group, University of Leicester, Leicester, UK; 2School of GeoSciences, University of Edinburgh, Edinburgh, UK; 3Key Laboratory of the Middle Atmosphere and Global Environmental Observation, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China

Satellites have the power to provide new insights into the regional sources and sinks of the major greenhouse gases (GHG) CO2 and CH4 thanks to their high data density and coverage. Satellite observations play an important role in diagnosing regions where carbon is taken up and released and how these fluxes respond to climate extremes such as droughts. Recently, the focus has further expanded with the aim of separating natural from anthropogenic emission sources.

Since the launch of the first dedicated GHG sensor GOSAT almost a decade ago, a series of new sensors have been launched (NASA OCO-2, TanSat, S5P…) with further sensors expected to be launched in the coming years (GOSAT-2, MicroCarb, OCO-3…). As a consequence, we are now presented with the opportunity of an emerging ad-hoc constellation of GHG satellites providing us with an opportunity to intercompare and eventually combine observations from multiple satellites to increase data coverage and density. However, one concern is potential biases between the datasets and careful validation against ground-based datasets is essential.

China is a key region for the global carbon and methane cycle with significant emission sources. However, the frequent occurrence of high aerosol loads over China combined with insufficient ground-based validation opportunities leaves satellite observations uncertain. In this presentation, we will focus on an evaluation of satellite observations of CO2 and CH4 over China. We will intercompare GOSAT, OCO2 and TanSat datasets and assess them against model calculations that are constrained with surface in-situ data. Finally, we will discuss the use of space-based data to identify and highlight main emission areas of GHGs.


Oral
ID: 263 / WS#1 ID.32301: 3
Oral Presentation
Atmosphere, Climate & Carbon: 32301 - Monitoring Greenhouse Gases from Space

Remote Sensing of Greenhouse Gases at the Finnish Meteorological Institue: Ssatellite Validation and Data Analysis

Johanna Tamminen1, Janne Hakkarainen1, Rigel Kivi1, Hannakaisa Lindqvist1, Ella Kivimäki1, Erkki Kyrölä1, Yi Liu2, Hartmut Boesch3

1Finnish Meteorological Institute, Finland; 2Institute of Atmospheric Physics, Chinse Academy of Sciences, Beijing, China; 3University of Leicester, Leicester, United Kingdom

We discuss the recent recearch activities that have taken place at the Finnish Meteorological Institute related to satellite observations of greenhouse gases with links to the DRAGON project “Monitoring greenhouse gases from space: Cal/Val and applications with focus in China and high latitudes“.

The FTIR instrument in Finnish Meteorological Institute’s premise in Sodankylä is one of the sites participating in the Total Carbon Column Observing Network (TCCON). The retrievals include column-averaged, dry-air mole fractions of carbon dioxide (XCO2) and methane (XCH4). Since 2013, series of AirCore balloon launches have been performed to obtain accurate in-situ profiles of methane, carbon dioxide and carbon monoxide from troposphere to lower stratosphere. As a high latitude site, Sodankylä contributes to the validation of satellite observations of greenhouse gases in boreal and arctic regions. The recent and on-going validation activities and campaigns that have taken place in Sodankylä are also discussed.

In addition, we have studied the spatiotemporal distribution of greenhouse gases by analysing spatially and temporally OCO-2 and GOSAT data. The developed methods and results are applicable also to TanSat data.


Poster
ID: 141 / WS#1 ID.32301: 4
Poster
Atmosphere, Climate & Carbon: 32301 - Monitoring Greenhouse Gases from Space

Global XCO2 anomalies as seen by Orbiting Carbon Observatory-2

Janne Hakkarainen

Finnish Meteorological Institute, Finland

Anthropogenic CO2 emissions from fossil fuel combustion have large impacts on climate. In order to monitor the increasing CO2 concentrations in the atmosphere, accurate spaceborne observations—as available from the Orbiting Carbon Observatory-2 (OCO-2)—are needed. In our recent work [Hakkarainen et al., 2016] we provided a new approach to study anthropogenic CO2 emission areas by deseasonalizing and detrending OCO-2 XCO2 observations for deriving XCO2 anomalies. The spatial distribution of the XCO2 anomaly matches the features observed in the maps of the Ozone Monitoring Instrument NO2 tropospheric columns, used as an indicator of atmospheric pollution, as well as the features observed in the ODIAC emission dataset. In addition, the results of a cluster analysis confirmed the correlation between CO2 and NO2 spatial patterns.

In this work, we study this idea further and provide the global XCO2 anomaly maps for three full years 2015, 2016 and 2017. The patterns observed in these maps are compared with inventory-based estimates given by the Lagrangian particle dispersion model FLEXPART driven by the high-resolution ODIAC emission dataset. We also analyze the changes observed in XCO2 anomaly maps and compare these changes to the inventory-based estimates, as well as to the changes observed in other trace gases (NO2 and SO2).

References

Hakkarainen, J., I. Ialongo, and J. Tamminen (2016), Direct space-based observations of anthropogenic CO2 emission areas from OCO-2, Geophys. Res. Lett., 43, 11,400–11,406, doi:10.1002/2016GL070885.


Poster
ID: 231 / WS#1 ID.32301: 5
Poster
Atmosphere, Climate & Carbon: 32301 - Monitoring Greenhouse Gases from Space

Anthropogenic CO2 Emission Signals Observed From Space

Nikoleta Kalaitzi1,2,3, Hartumt Boesch1,2,3, Robert Parker1,2,3, Dongxu Yang6, Yi Liu6, Paul Palmer4,5, Liang Feng4,5

1Earth Observation Science, Department of Physics and Astronomy, University Of Leicester, United Kingdom; 2National Centre for Earth Observation, University of Leicester, Leicester, UK; 3Leicester Institute for Space and Earth Observation, University of Leicester, Leicester, UK; 4School of GeoSciences, University of Edinburgh, Edinburgh, UK; 5National Centre for Earth Observation, School of GeoSciences, University of Edinburgh, Edinburgh, UK; 6Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China

CO2 anthropogenic emissions contribute 37 Gt CO2 to the global carbon budget. The emissions of carbon dioxide arise from different anthropogenic activities with the dominant contribution from burning of fossil fuel especially for power generation and the industry and transport sectors. The quickly growing economy of China has, in recent years, become the largest emitter of CO2 generating about 30% of all emissions. Cities and urban areas, where the human activities are very intense, are responsible for over 70% of all CO2 emissions highlighted the need for a better understanding of emissions form these urban areas.

New satellite observations of CO2, in particular from NASA’s OCO-2 launched in 2014 and the Chinese TanSat launched in 2016 provide the opportunity to monitor CO2 concentration over polluted areas in the scale of big cities and individual point sources due to the small size of its footprint of ~ 4 km2.

The goal of this study is to investigate if and how well we can observe anthropogenic enhancement of total column dry air CO2 mole fraction (XCO2) from space over densely populated areas as well as for individual large cities. We will focus on Eastern China as well as selected megacities globally.

We will show an evaluation of current model calculations such as Copernicus Atmosphere Monitoring Service (CAMS) against space-based data and present first result based on a high-resolution modelling approach that allows interpretation of individual soundings/orbits.


Poster
ID: 259 / WS#1 ID.32301: 6
Poster
Atmosphere, Climate & Carbon: 32301 - Monitoring Greenhouse Gases from Space

Assessment of CO2 and CH4 in Xinglong during the Enhanced Observation Campaign in Beijing-Tianjin-Hebei Region: First Preliminary Results

Yang Yang, Wang Ting, Wangpu Cai, Zhoumin Qiang, Yao Bo

The Institute of Atmospheric Physics, Chinese Academy of Sciences, China, People's Republic of China

In recent years, the continuous rise in the concentrations of greenhouse gases has drawn a great attention of the international community, especially for carbon dioxide (CO2) and methane (CH4). The sources and sinks of CO2 and CH4 in the atmosphere are distributed unevenly and subjected to a variety of transport. The high-precision observation of CO2 and CH4 provides a foundation for the assessment of carbon emissions and a basis for the study of carbon cycle Much effort has been done by the government and research groups to monitor and quantify the magnitude and distribution of greenhouse gases, including both domestic and international.

High-accuracy continuous measurements of CO2 and CH4 at Xinglong (40°24'N, 117°30'E, 940 m a.s.l.) located at ~150km northeast of Beijing from May 2016 to December 2017 were made based on cavity ring down spectroscopy (CRDS) analyzer. The calibration data, seasonal and diurnal variations, influence of local wind and regional transport have been discussed. To understand different regional background in China, the seasonal cycles of CO2 and CH4 at Xinglong have been compared the results from Mt.Waliguan and Shangdianzi.

The calibration result shows that the accuracies of measurements of the instrument meet the compatibility goals of WMO/GAW. CO2 concentration is high in winter and low in summer while CH4 concentration is high in summer as well as in middle autumn and low in spring. The seasonal variation for CO2 is mainly due to the combination influence of photosynthesis and respiration of plants. The regional transportation is another important factor. The air mass from southwest-south-southeast of the station such as Beijing, Hebei and Jinan may contribute to the relative high concentrations, especially in summer and autumn. The higher CH4 concentration occurs in summer and middle autumn due to the gradual degradation of anaerobic microorganisms emitting large quantities of CH4 in local area and fossil combustion emissions from Beijing-Tianjin-Hebei in summer and autumn. What’s more, Mongolia is another potential source area for both CO2 and CH4 in autumn and winter.

The diurnal patterns of CO2 and CH4 both show relatively low value in the noon. For CO2 it is because the strong sunshine in the noon which is conductive to the stronger mixing of near-surface air with lower CO2 concentrations aloft. While for CH4 it is the increasing OH radicals in the atmosphere after sunrise that leads to the decrease of CH4.The stable boundary in the afternoon and at night helps the accumulations of CO2 and CH4 in the afternoon.

The seasonal variations of CO2 comparisons between Xinglong, Shangdianzi and Mt.Waliguan show that the patterns are the similar in the 3 sites for CO2,high in summer and low in other seasons. The pattern for CH4 at Xinglong is high in summer, middle autumn and winter while low in spring. However, the variation of atmospheric CH4 in Mt.Waliguan and Shangdianzi is only high in summer and smaller than other 2 stations.