Aki Tsuruta
A5082478831- Atmospheric and Environmental Gas Dynamics
- Atmospheric chemistry and aerosols
- Methane Hydrates and Related Phenomena
- Hydrocarbon exploration and reservoir analysis
- Atmospheric Ozone and Climate
- Peatlands and Wetlands Ecology
- Climate variability and models
- Climate change and permafrost
- Carbon Dioxide Capture Technologies
- Climate Change Policy and Economics
- Spectroscopy and Laser Applications
- Meteorological Phenomena and Simulations
- Cryospheric studies and observations
- Plant Water Relations and Carbon Dynamics
- Air Quality and Health Impacts
- Vehicle emissions and performance
- Geochemistry and Geologic Mapping
- CO2 Sequestration and Geologic Interactions
- Hydrology and Drought Analysis
- Hydrology and Watershed Management Studies
- Science and Climate Studies
- Tree-ring climate responses
- Radiomics and Machine Learning in Medical Imaging
- Solar Radiation and Photovoltaics
- Air Quality Monitoring and Forecasting
Finnish Meteorological Institute
2016-2025
Japan Agency for Marine-Earth Science and Technology
2024
Abstract. Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. Atmospheric emissions concentrations of CH4 continue increase, making second most human-influenced greenhouse gas in terms forcing, after carbon dioxide (CO2). The relative importance compared CO2 depends on its shorter atmospheric lifetime, stronger warming potential, variations growth rate over past decade, causes which are still debated. Two...
The ongoing development of the Global Carbon Project (GCP) global methane (CH4 ) budget shows a continuation increasing CH4 emissions and accumulation in atmosphere during 2000-2017. Here, we decompose into 19 regions (18 land 1 oceanic) five key source sectors to spatially attribute observed trends. A comparison top-down (TD) (atmospheric transport model-based) bottom-up (BU) (inventory- process emission estimates demonstrates robust temporal trends with 16 regions. Five regions-China,...
Abstract. Understanding and quantifying the global methane (CH4) budget is important for assessing realistic pathways to mitigate climate change. Emissions atmospheric concentrations of CH4 continue increase, maintaining as second most human-influenced greenhouse gas in terms forcing after carbon dioxide (CO2). The relative importance compared CO2 temperature change related its shorter lifetime, stronger radiative effect, acceleration growth rate over past decade, causes which are still...
Abstract Emissions from fossil fuel exploitation are a leading contributor to global anthropogenic methane emissions, but highly uncertain. The lack of reliable estimates hinders monitoring the progress on pledges towards reductions. Here we analyze emissions coal, oil and gas for major producing nations across suite bottom-up inventories inversions. Larger disagreement in exists oil/gas sector compared arising mostly disparate data sources emission factors. Moreover, reported United Nations...
Abstract. Data assimilation systems are used increasingly to constrain the budgets of reactive and long-lived gases measured in atmosphere. Each trace gas has its own lifetime, dominant sources sinks, observational network (from flask sampling situ measurements space-based remote sensing) therefore comes with optimal configuration data assimilation. The CarbonTracker Europe system for CO2 estimates global carbon updates released annually cycle studies. simulations performed using new modular...
Abstract. We present inverse modelling (top down) estimates of European methane (CH4) emissions for 2006–2012 based on a new quality-controlled and harmonised in situ data set from 18 atmospheric monitoring stations. applied an ensemble seven models performed four inversion experiments, investigating the impact different sets stations use priori information emissions. The infer total CH4 26.8 (20.2–29.7) Tg yr−1 (mean, 10th 90th percentiles all inversions) EU-28 experiments. For comparison,...
Abstract The recent rise in atmospheric methane (CH 4 ) concentrations accelerates climate change and offsets mitigation efforts. Although wetlands are the largest natural CH source, estimates of global wetland emissions vary widely among approaches taken by bottom‐up (BU) process‐based biogeochemical models top‐down (TD) inversion methods. Here, we integrate situ measurements, multi‐model ensembles, a machine learning upscaling product into International Land Model Benchmarking system to...
Abstract. We present a global distribution of surface methane (CH4) emission estimates for 2000–2012 derived using the CarbonTracker Europe-CH4 (CTE-CH4) data assimilation system. In CTE-CH4, anthropogenic and biospheric CH4 emissions are simultaneously estimated based on constraints atmospheric in situ observations. The system was configured to either estimate only or sources per region, both categories simultaneously. latter increased number optimizable parameters from 62 78. addition,...
We employed a global high-resolution inverse model to optimize the CH4 emission using Greenhouse gas Observing Satellite (GOSAT) and surface observation data for period from 2011–2017 two main source categories of anthropogenic natural emissions. used Emission Database Global Atmospheric Research (EDGAR v4.3.2) methane scaled them by country match national inventories reported United Nations Framework Convention on Climate Change (UNFCCC). Wetland soil sink prior fluxes were simulated...
We present a global 0.1° × high-resolution inverse model, NIES-TM-FLEXPART-VAR (NTFVAR), and methane emission evaluation using the Greenhouse Gas Observing Satellite (GOSAT) satellite ground-based observations from 2010–2012. Prior fluxes contained two variants of anthropogenic emissions, Emissions Database for Global Atmospheric Research (EDGAR) v4.3.2 adjusted EDGAR which were scaled to match country totals by national reports United Nations Framework Convention on Climate Change (UNFCCC),...
Abstract. Atmospheric inversion approaches are expected to play a critical role in future observation-based monitoring systems for surface fluxes of greenhouse gases (GHGs), pollutants and other trace gases. In the past decade, research community has developed various software, mainly using variational or ensemble Bayesian optimization methods, with assumptions on uncertainty structures prior information atmospheric chemistry–transport models. Each them can assimilate some all available...
Abstract. Reliable quantification of the sources and sinks greenhouse gases, together with trends uncertainties, is essential to monitoring progress in mitigating anthropogenic emissions under Paris Agreement. This study provides a consolidated synthesis CH4 N2O consistently derived state-of-the-art bottom-up (BU) top-down (TD) data for European Union UK (EU27 + UK). We integrate recent emission inventory data, ecosystem process-based model results inverse modeling estimates over period...
Recent advances in satellite observations of methane provide increased opportunities for inverse modeling. However, challenges exist the observation optimization and retrievals high latitudes. In this study, we examine possibilities use total column averaged dry-air mole fractions (XCH4) data over land from TROPOspheric Monitoring Instrument (TROPOMI) on board Sentinel 5 Precursor estimation CH4 fluxes using CarbonTracker Europe-CH4 (CTE-CH4) atmospheric model. We carry out simulations...
Abstract. Knowledge of the spatial distribution fluxes greenhouse gases (GHGs) and their temporal variability as well flux attribution to natural anthropogenic processes is essential monitoring progress in mitigating emissions under Paris Agreement inform its global stocktake. This study provides a consolidated synthesis CH4 N2O using bottom-up (BU) top-down (TD) approaches for European Union UK (EU27 + UK) updates earlier syntheses (Petrescu et al., 2020, 2021). The work integrates updated...
Abstract. Wetland methane responses to temperature and precipitation were studied in a boreal wetland-rich region Northern Europe using ecosystem process models. Six models (JSBACH-HIMMELI, LPX-Bern, LPJ-GUESS, JULES, CLM4.5 CLM5) compared multi-model mean of atmospheric inversions from the Global Carbon Project up-scaled eddy covariance flux results for their seasonal cycles regional fluxes. Two with contrasting response patterns, LPX-Bern JSBACH-HIMMELI, used as priors Tracker – CH4 order...
Abstract. In this study, we provide an update of the methodology and data used by Deng et al. (2022) to compare national greenhouse gas inventories (NGHGIs) atmospheric inversion model ensembles contributed international research teams coordinated Global Carbon Project. The comparison framework uses transparent processing net ecosystem exchange fluxes carbon dioxide (CO2) from inversions estimates terrestrial stock changes over managed land that can be evaluate NGHGIs. For methane (CH4),...
Abstract. Wetland methane responses to temperature and precipitation are studied in a boreal wetland-rich region northern Europe using ecosystem process models. Six models (JSBACH-HIMMELI, LPX-Bern, LPJ-GUESS, JULES, CLM4.5, CLM5) compared multi-model means of atmospheric inversions from the Global Carbon Project upscaled eddy covariance flux results for their seasonal cycles regional fluxes. Two with contrasting response patterns, LPX-Bern JSBACH-HIMMELI, used as priors Tracker Europe–CH4...
Abstract. The influence of drought on plant functioning has received considerable attention in recent years, however our understanding the response carbon and water coupling to terrestrial ecosystems still needs be improved. A severe soil moisture occurred southern Finland late summer 2006. In this study, we investigated use efficiency a boreal Scots pine forest (Pinus sylvestris) daily time scale mainly using eddy covariance flux data from Hyytiälä (southern Finland) site. addition,...
Abstract. Accurate and precise observations of atmospheric greenhouse gas mixing ratios are crucial for understanding the carbon cycle. However, challenges can arise when comparing data between different observation sites, due to measurement routines formats used. To combat these challenges, research infrastructures have been established in order harmonize processing make from stations readily available. One few boreal region that observes is Pallas station, located atop Sammaltunturi fell...
Abstract. Methane emissions from Northern high-latitude wetlands are associated with large uncertainties, especially in the rapidly warming climate. Satellite observations of column-averaged methane concentrations (XCH4) atmosphere exhibit variability due to time-varying sources and sinks. In this study, we investigate how environmental variables, such as temperature, soil moisture, snow cover, hydroxyl radical (OH) sink methane, explain seasonal observed space over wetland areas. We use...
Abstract. Satellite-driven inversions provide valuable information about methane (CH4) fluxes, but the assimilation of total column-averaged dry-air mole fractions CH4 (XCH4) has been challenging. This study explores, for first time, potential new lower tropospheric partial column (pXCH4_LT) GOSAT data, retrieved by Japan Aerospace Exploration Agency (JAXA), to constrain global and regional fluxes. Using CarbonTracker Europe-CH4 atmospheric inverse model, we estimated fluxes between...
Abstract. Accurate national methane (CH4) emission estimates are essential for tracking progress towards climate goals. This study investigated Finnish CH4 emissions from 2000–2021 using bottom-up and top-down approaches. We evaluated the ability of a global atmospheric inverse model CarbonTracker Europe – to estimate within single country. focused on how different priors their uncertainties affect optimised showed that anthropogenic natural were strongly dependent prior emissions. However,...
Abstract. The Community Inversion Framework (CIF) brings together methods for estimating greenhouse gas fluxes from atmospheric observations. While the analytical and variational optimization implemented in CIF are operational have proved to be accurate efficient, initial ensemble method was found incomplete could hardly compared other employed inversion community, mainly owing strong performance limitations absence of localization methods. In this paper, we present evaluate a new...
The northern high latitudes (NHLs) are undergoing rapid environmental changes with global warming, which may trigger feedback mechanisms that amplify natural methane emissions from wetlands and increase contributions wildfires. Studying year-to-year variations in these can provide understanding of the key factors driving fluxes. In addition, NHLs produce substantial fossil fuel production. However, spatial heterogeneity overlap sources region complicates attribution to specific...