Akinori Ito

Japan Agency for Marine-Earth Science and Technology

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Jasper F. Kok

University of California, Los Angeles

N. M. Mahowald

Cornell University

Joyce E. Penner

University of Michigan–Ann Arbor

Michio Kawamiya

Japan Agency for Marine-Earth Science and Technology

A. Yamamoto

Japan Agency for Marine-Earth Science and Technology

Rumi Ohgaito

Japan Agency for Marine-Earth Science and Technology

Tomohiro Hajima

Japan Agency for Marine-Earth Science and Technology

Adeyemi A. Adebiyi

University of California, Merced

Douglas S. Hamilton

North Carolina State University

Stelios Myriokefalitakis

National Observatory of Athens

Cooperative Institutions

Centre National de la Recherche Scientifique

107

Fermi National Accelerator Laboratory

University of Buenos Aires

Universidad de Los Andes

The University of Tokyo

Institut National de Physique Nucléaire et de Physique des Particules

Charles University

Czech Academy of Sciences, Institute of Physics

Japan Agency for Marine-Earth Science and Technology

Universidad San Francisco de Quito

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Dust Constraints from joint Observational-Modelling-experiMental analysis – DustCOMM Version 1.1

Zenodo (CERN European Organization for Nuclear Research) (2019)

Adebiyi Adeyemi Kok Jasper Yang Wang Akinori Ito D. A. Ridley

Dust Constraints from joint Observational-Modelling-experiMental analysis – DustCOMM Version 1.1 NOTE: PLEASE, USE THIS VERSION OF THE DATASET This is the version-1 of DustCOMM dataset (Adebiyi et al. Geoscientific Model Development), containing annual and seasonal climatologies of constrained dust aerosol properties, including spatially-varying dust size distribution, mass extinction efficiency, and atmospheric dust loading. Please be aware that there will be future versions of DustCOMM that incorporates more observational, modeling and experimental constraints. Please send an email to the corresponding authors if you have any question or would like to receive update of DustCOMM's future developments. Below, we give a brief description of each data file. In each, we have included the mean, median, 1 and 2 sigma uncertainty estimates as a function of location. These uncertainty estimates are derived from probability distributions that describe the field over each location. Please contact the corresponding authors if you are interested in the full dataset. The dimensions in these dataset are denoted as:
lon [144] -- Longitude. Unit of degrees_east. Global - 2.5 deg resolution.
lat [96] -- Latitude. Unit of degrees_north. Global - ~2 deg resolution
lev [35] -- Pressure levels. Unit of hPa. ~900 hPa to 100 hPa. Lower resolution in the boundary layer and higher resolution in the free troposphere.
D [200] -- Dust Geometric Diameter. Unit of microns. From 0.2-20 microns.
nseas [4] -- Seasons. They are DJF, MAM, JJA, and SON corresponding to December-January-February, March-April-May, June-July-August, and September-October-December respectively.
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Dust_Size_Distr_dVdD_annual.nc - Dimension: [lon, lat, lev, D]
Dust_Size_Distr_dVdD_seasonal.nc - Dimension: [nseas, lon, lat, lev, D] -- DustCOMM annual and seasonal climatologies of 3-D normalized dust (volume) size distribution. Fields include:
-> dVdD_mean -- Mean Normalized Dust Volume Size Distribution
-> dVdD_median -- Median Normalized Dust Volume Size Distribution
-> dVdD_Pos1sig -- +1 Sigma Normalized Dust Volume Size Distribution
-> dVdD_Neg1sig -- -1 Sigma Normalized Dust Volume Size Distribution
-> dVdD_Pos2sig -- +2 Sigma Normalized Dust Volume Size Distribution
-> dVdD_Neg2sig -- -2 Sigma Normalized Dust Volume Size Distribution --------
Dust_3D_MEE_annual.nc - Dimension: [lon, lat, lev]
Dust_3D_MEE_seasonal.nc - Dimension: [nseas, lon, lat, lev] -- DustCOMM annual and seasonal climatologies of 3-D dust mass extinction efficiency (m2/g). Fields include:
-> MEE_mean -- Mean Dust 3D Mass Extinction Efficiency
-> MEE_median -- Median Dust 3D Mass Extinction Efficiency
-> MEE_Pos1sig -- +1 Sigma Dust 3D Mass Extinction Efficiency
-> MEE_Neg1sig -- -1 Sigma Dust 3D Mass Extinction Efficiency
-> MEE_Pos2sig -- +2 Sigma Dust 3D Mass Extinction Efficiency
-> MEE_Neg2sig -- -2 Sigma Dust 3D Mass Extinction Efficiency --------
Dust_2D_MEE_annual.nc - Dimension: [lon, lat]
Dust_2D_MEE_seasonal.nc - Dimension: [nseas, lon, lat] -- DustCOMM annual and seasonal climatologies of 2-D dust mass extinction efficiency (m2/g). Fields include:
-> MEE_mean -- Mean Dust 2D Mass Extinction Efficiency
-> MEE_median -- Median Dust 2D Mass Extinction Efficiency
-> MEE_Pos1sig -- +1 Sigma Dust 2D Mass Extinction Efficiency
-> MEE_Neg1sig -- -1 Sigma Dust 2D Mass Extinction Efficiency
-> MEE_Pos2sig -- +2 Sigma Dust 2D Mass Extinction Efficiency
-> MEE_Neg2sig -- -2 Sigma Dust 2D Mass Extinction Efficiency --------
Dust_Load_annual.nc - Dimension: [lon, lat]
Dust_Load_seasonal.nc - Dimension: [nseas, lon, lat] -- DustCOMM annual and seasonal climatologies of 2-D atmospheric dust loading (g/m2). Fields include:
-> Load_mean -- Mean Atmospheric Dust Loading
-> Load_median -- Median Atmospheric Dust Loading
-> Load_Pos1sig -- +1 Sigma Atmospheric Dust Loading
-> Load_Neg1sig -- -1 Sigma Atmospheric Dust Loading
-> Load_Pos2sig -- +2 Sigma Atmospheric Dust Loading
-> Load_Neg2sig -- -2 Sigma Atmospheric Dust Loading ========================== Correspondng Authors:
Adeyemi Adebiyi and Jasper Kok
Department of Atmospheric and Oceanic Sciences,
University of California Los Angeles, CA, USA
Email: aadebiyi@ucla.edu and jfkok@ucla.edu

10.5281/zenodo.2620474

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Contribution of combustion Fe in marine aerosols over the northwestern Pacific estimated by Fe stable isotope ratios

Minako Kurisu Kohei Sakata Mitsuo Uematsu Akinori Ito Yoshio Takahashi

Abstract. The source apportionment of aerosol iron (Fe), including natural and combustion Fe, is an important issue because aerosol Fe can enhance oceanic primary production in the surface ocean. Based on our previous finding that combustion Fe emitted by evaporation processes has Fe isotope ratios (δ56Fe) that are approximately 4 ‰ lower than those of natural Fe, this study aimed to distinguish aerosol Fe sources over the northwestern Pacific using two size-fractionated marine aerosols. The δ56Fe values of fine and coarse particles from the eastern or northern Pacific were found to be similar to each other, ranging from 0.0 to 0.4 ‰. Most of them were close to the crustal average, suggesting the dominance of natural Fe. On the other hand, particles from East Asia demonstrated lower δ56Fe values in fine particles (−0.5 to −2.2 ‰) than in coarse particles (on average 0.1 ‰). The correlations between the δ56Fe values and the enrichment factors of lead and vanadium suggested that the low δ56Fe values obtained were due to the presence of combustion Fe. The δ56Fe values of the soluble component of fine particles in this region were lower than the total, indicating the preferential dissolution of combustion Fe. In addition, we found a negative correlation between the δ56Fe value and the fractional Fe solubility in air masses from East Asia. These results suggested that the presence of combustion Fe is an important factor in controlling the fractional Fe solubility in air masses from East Asia, whereas other factors were more important in the other areas. By assuming typical δ56Fe values for combustion and natural Fe, the contribution of combustion Fe to the total (acid-digested) Fe in aerosols was estimated to reach up to 50 % of fine and 21 % of bulk (coarse + fine) particles in air masses from East Asia, whereas its contribution was small in the other areas. The contribution of combustion Fe to the soluble Fe component estimated for one sample was approximately twice as large as the total, indicating the importance of combustion Fe as a soluble Fe source, despite lower emissions than the natural. These isotope-based estimates were compared with those estimated using an atmospheric chemical transport model (IMPACT), in which the fractions of combustion Fe in fine particles, especially in air masses from East Asia, were consistent with each other. In contrast, the model estimated a relatively large contribution from combustion Fe in coarse particles, probably because of the different characteristics of combustion Fe that are included in the model calculation and the isotope-based estimation. This highlights the importance of observational data of δ56Fe for size-fractionated aerosols to scale the combustion Fe emission by the model. The average deposition fluxes of soluble Fe to the surface ocean were 1.4 and 2.9 nmol m−2 day−1 from combustion and natural aerosols, respectively, in air masses from East Asia, which suggests combustion Fe could be an important Fe source to the surface seawater among other Fe sources. Distinguishing Fe sources using the δ56Fe values of marine aerosols and seawater is anticipated to lead to a more quantitative understanding of the Fe cycle in the atmosphere and surface ocean.

Dominance (genetics)

Enrichment factor

10.5194/acp-2021-460

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A terrestrial biosphere model optimized to atmospheric CO2 concentration and above ground woody biomass

AGU Fall Meeting Abstracts (2013)

Makoto Saito Akinori Ito S. S. Maksyutov

Terrestrial ecosystem

Biosphere model

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Iron mobilization in North African Dust

Procedia Environmental Sciences (2011)

Akinori Ito Yan Feng

Iron is an essential nutrient for phytoplankton. Although iron-containing dust mobilized from arid regions supplies the majority of the iron to the oceans, the key flux in terms of the biogeochemical response to atmospheric deposition is the amount of soluble or bioavailable iron. Atmospheric processing of mineral aerosols by anthropogenic pollutants (e.g. sulfuric acid) may transform insoluble iron into soluble forms. Previous studies have suggested higher iron solubility in smaller particles, as they are subject to more thorough atmospheric processing due to a longer residence time than coarse particles. On the other hand, the specific mineralogy of iron in dust may also influence the particulate iron solubility in size. Compared to mineral dust aerosols, iron from combustion sources could be more soluble, and found more frequently in smaller particles. Internal mixing of alkaline dust with iron-containing minerals could significantly reduce iron dissolution in large dust aerosols due to the buffering effect, which may, in contrast, yield higher solubility in smaller particles externally mixed with alkaline dust (Ito and Feng, 2010). Here, we extend the modeling study of Ito and Feng (2010) to investigate atmospheric processing of mineral aerosols from African dust. In contrast to Asian dust, we used a slower dissolution rate for African dust in the fine mode. We compare simulated fractional iron solubility with observations. The inclusion of alkaline compounds in aqueous chemistry substantially limits the iron dissolution during long-range transport to the Atlantic Ocean: only a small fraction of iron (<0.2%) dissolves from illite in coarsemode dust aerosols with 0.45% soluble iron initially. In contrast, a significant fraction (1–1.5%) dissolves in fine-mode dust aerosols due to the acid mobilization of the iron-containing minerals externally mixed with carbonate minerals. Consequently, the model generally reproduces higher iron solubility in smaller particles as suggested by measurements over the Atlantic Ocean. Our results imply that the dissolution of iron in African dust is generally slower than that in Asian dust. Conventionally, dust is assumed as the major supply of bioavailable iron with a constant solubility at 1–2% to the remote ocean. Therefore, the timing and location of the atmospheric iron input to the ocean with detailed modeling of atmospheric processing could be different from those previously assumed. Past and future changes in aerosol supply of bioavailable iron might play a greater role in the nutrient supply for phytoplankton production in the upper ocean, as global warming has been predicted to intensify stratification and reduce vertical mixing from the deep ocean. Thus the feedback of climate change through ocean uptake of carbon dioxide as well as via aerosol-cloud interaction might be modified by the inclusion of iron chemistry in the atmosphere.

Mineral dust

Iron fertilization

Deposition

10.1016/j.proenv.2011.05.004

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Citations (4)

Global modeling study of soluble organic nitrogen from open biomass burning

Atmospheric Environment (2015)

Akinori Ito Guangxing Lin Joyce E. Penner

Atmospheric deposition of reactive nitrogen (N) species from large fires may contribute to enrichment of nutrients in aquatic ecosystems. Here we use an atmospheric chemistry transport model to investigate the supply of soluble organic nitrogen (ON) from open biomass burning to the ocean. The model results show that the annual deposition rate of soluble ON to the oceans (14 Tg N yr−1) is increased globally by 13% with the increase being particularly notable over the tropical oceans downwind from the source regions. The estimated deposition of soluble ON due to biomass burning from the secondary formation (1.0 Tg N yr−1) is close to that from the primary sources (1.2 Tg N yr−1). We examine the secondary formation of particulate C–N compounds (i.e., imidazole, methyl imidazole, and N-containing oligomers) from the reactions of glyoxal (CHOCHO) and methylglyoxal (CH3COCHO) with ammonium (NH4+) in wet aerosols and upon cloud evaporation. These ON sources result in a significant contribution to the open ocean (1.3 Tg N yr−1), suggesting that atmospheric processing in aqueous-phase may have a large effect. We compare the soluble ON concentration in aerosols with and without open biomass burning as a case study in Singapore. The model results demonstrate that the soluble ON concentration in aerosols is episodically enriched during the fire events, compared to the case without smoke simulations. At the same time, the model results show that the daily soluble ON concentration can be also enhanced in the case without smoke simulations, compared to the monthly averages. These results may suggest that both the primary source strength of ON and the secondary formation rates of ON should be taken into consideration when using in-situ observations to constrain the calculated soluble ON burden due to biomass burning. More accurate quantification of the soluble ON burdens both with and without smoke sources is therefore needed to assess the effect of biomass burning on bioavailable ON input to the oceans.

Glyoxal

Deposition

Atmospheric chemistry

Primary producers

Reactive nitrogen

10.1016/j.atmosenv.2015.01.031

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Citations (25)

Atmospheric Deposition of Soluble Organic Nitrogen due to Biomass Burning

2014 AGU Fall Meeting (2014)

Akinori Ito Guan-Yu Lin Joyce E. Penner

Deposition

Source

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Multi-model analysis of terrestrial water and carbon cycles in Japan: Japan-MIP

AGU Fall Meeting Abstracts (2008)

Kazuhito Ichii Tatsuo Suzuki Tomomichi Kato Akinori Ito T. Sasai

Terrestrial ecosystem

Carbon fibers

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Comment on acp-2021-460

Minako Kurisu Kohei Sakata Mitsuo Uematsu Akinori Ito Yoshio Takahashi

Abstract. The source apportionment of aerosol iron (Fe), including natural and combustion Fe, is an important issue because aerosol Fe can enhance oceanic primary production in the surface ocean. Based on our previous finding that combustion Fe emitted by evaporation processes has Fe isotope ratios (Î´⁵⁶Fe) that are approximately 4ââ° lower than those of natural Fe, this study aimed to distinguish aerosol Fe sources over the northwestern Pacific using two size-fractionated marine aerosols. The Î´⁵⁶Fe values of fine and coarse particles from the eastern or northern Pacific were found to be similar to each other, ranging from 0.0ââ° to 0.4ââ°. Most of them were close to the crustal average, suggesting the dominance of natural Fe. On the other hand, particles from the direction of East Asia demonstrated lower Î´⁵⁶Fe values in fine particles (â0.5ââ° to â2.2ââ°) than in coarse particles (on average â0.02âÂ±â0.12ââ°). The correlations between the Î´⁵⁶Fe values and the enrichment factors of lead and vanadium suggested that the low Î´⁵⁶Fe values obtained were due to the presence of combustion Fe. The Î´⁵⁶Fe values of the soluble component of fine particles in this region were lower than the total, indicating the preferential dissolution of combustion Fe. In addition, we found a negative correlation between the Î´⁵⁶Fe value and the fractional Fe solubility in air masses from the direction of East Asia. These results suggest that the presence of combustion Fe is an important factor in controlling the fractional Fe solubility in air masses from the direction of East Asia, whereas other factors are more important in the other areas. By assuming typical Î´⁵⁶Fe values for combustion and natural Fe, the contribution of combustion Fe to the total (acid-digested) Fe in aerosols was estimated to reach up to 50â% of fine and 21â% of bulk (coarseâ+âfine) particles in air masses from the direction of East Asia, whereas its contribution was small in the other areas. The contribution of combustion Fe to the soluble Fe component estimated for one sample was approximately twice as large as the total, indicating the importance of combustion Fe as a soluble Fe source despite lower emissions than the natural. These isotope-based estimates were compared with those estimated using an atmospheric chemical transport model (IMPACT), in which the fractions of combustion Fe in fine particles, especially in air masses from the direction of East Asia, were consistent with each other. In contrast, the model estimated a relatively large contribution from combustion Fe in coarse particles, probably because of the different characteristics of combustion Fe that are included in the model calculation and the isotope-based estimation. This highlights the importance of observational data on Î´⁵⁶Fe for size-fractionated aerosols to scale the combustion Fe emission by the model. The average deposition fluxes of soluble Fe to the surface ocean were 1.4 and 2.9ânmolâm^â2âd^â1 from combustion and natural aerosols, respectively, in air masses from the direction of East Asia, which suggests that combustion Fe could be an important Fe source to the surface seawater among other Fe sources. Distinguishing Fe sources using the Î´⁵⁶Fe values of marine aerosols and seawater is anticipated to lead to a more quantitative understanding of the Fe cycle in the atmosphere and surface ocean.

10.5194/acp-2021-460-rc1

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CCDC 892081: Experimental Crystal Structure Determination

The Cambridge Structural Database (2013)

Y. Akai Yutaka Tabuchi K. Ando Akinori Ito Y Sakata

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

10.5517/ccyy8ty

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Radiative forcing of iron oxides from combustion sources

AGUFM (2017)

Akinori Ito Guangxing Lin Joyce E. Penner

Forcing (mathematics)

Source

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