8 results on '"Tanaka, TY"'
Search Results
2. Large-scale tropospheric transport in the Chemistry-Climate Model Initiative (CCMI) simulations
- Author
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Orbe, C, Yang, H, Waugh, DW, Zeng, G, Morgenstern, O, Kinnison, DE, Lamarque, J-F, Tilmes, S, Plummer, DA, Scinocca, JF, Josse, B, Marecal, V, Joeckel, P, Oman, LD, Strahan, SE, Deushi, M, Tanaka, TY, Yoshida, K, Akiyoshi, H, Yamashita, Y, Stenke, A, Revell, L, Sukhodolov, T, Rozanov, E, Pitari, G, Visioni, D, Stone, KA, Schofield, R, Banerjee, A, Orbe, C, Yang, H, Waugh, DW, Zeng, G, Morgenstern, O, Kinnison, DE, Lamarque, J-F, Tilmes, S, Plummer, DA, Scinocca, JF, Josse, B, Marecal, V, Joeckel, P, Oman, LD, Strahan, SE, Deushi, M, Tanaka, TY, Yoshida, K, Akiyoshi, H, Yamashita, Y, Stenke, A, Revell, L, Sukhodolov, T, Rozanov, E, Pitari, G, Visioni, D, Stone, KA, Schofield, R, and Banerjee, A
- Abstract
Understanding and modeling the large-scale transport of trace gases and aerosols is important for interpreting past (and projecting future) changes in atmospheric composition. Here we show that there are large differences in the global-scale atmospheric transport properties among the models participating in the IGAC SPARC Chemistry–Climate Model Initiative (CCMI). Specifically, we find up to 40% differences in the transport timescales connecting the Northern Hemisphere (NH) midlatitude surface to the Arctic and to Southern Hemisphere high latitudes, where the mean age ranges between 1.7 and 2.6 years. We show that these differences are related to large differences in vertical transport among the simulations, in particular to differences in parameterized convection over the oceans. While stronger convection over NH midlatitudes is associated with slower transport to the Arctic, stronger convection in the tropics and subtropics is associated with faster interhemispheric transport. We also show that the differences among simulations constrained with fields derived from the same reanalysis products are as large as (and in some cases larger than) the differences among free-running simulations, most likely due to larger differences in parameterized convection. Our results indicate that care must be taken when using simulations constrained with analyzed winds to interpret the influence of meteorology on tropospheric composition.
- Published
- 2018
3. Review of the global models used within the Chemistry-Climate Model Initiative (CCMI)
- Author
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Morgenstern, O, Hegglin, MI, Rozanov, E, O'Connor, FM, Abraham, NL, Akiyoshi, H, Archibald, AT, Bekki, S, Butchart, N, Chipperfield, MP, Deushi, M, Dhomse, SS, Garcia, RR, Hardiman, SC, Horowitz, LW, Jöckel, P, Josse, B, Kinnison, D, Lin, M, Mancini, E, Manyin, ME, Marchand, M, Marécal, V, Michou, M, Oman, LD, Pitari, G, Plummer, DA, Revell, LE, Saint-Martin, D, Schofield, R, Stenke, A, Stone, K, Sudo, K, Tanaka, TY, Tilmes, S, Yamashita, Y, Yoshida, K, and Zeng, G
- Abstract
We present an overview of state-of-the-artchemistry–climate and chemistry transport models that areused within phase 1 of the Chemistry–Climate Model Initia-tive (CCMI-1). The CCMI aims to conduct a detailed evalua-tion of participating models using process-oriented diagnos-tics derived from observations in order to gain confidence inthe models’ projections of the stratospheric ozone layer, tro-pospheric composition, air quality, where applicable globalclimate change, and the interactions between them. Interpre-tation of these diagnostics requires detailed knowledge of theradiative, chemical, dynamical, and physical processes incor-porated in the models. Also an understanding of the degree towhich CCMI-1 recommendations for simulations have beenfollowed is necessary to understand model responses to an-thropogenic and natural forcing and also to explain inter-model differences. This becomes even more important giventhe ongoing development and the ever-growing complexityof these models. This paper also provides an overview ofthe available CCMI-1 simulations with the aim of informingCCMI data users., Geoscientific Model Development, 10 (2), ISSN:1991-9603, ISSN:1991-959X
- Published
- 2017
4. Review of the global models used within phase 1 of the Chemistry-Climate Model Initiative (CCMI)
- Author
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Morgenstern, O, Hegglin, MI, Rozanov, E, O'Connor, FM, Abraham, NL, Akiyoshi, H, Archibald, AT, Bekki, S, Butchart, N, Chipperfield, MP, Deushi, M, Dhomse, SS, Garcia, RR, Hardiman, SC, Horowitz, LW, Joeckel, P, Josse, B, Kinnison, D, Lin, M, Mancini, E, Manyin, ME, Marchand, M, Marecal, V, Michou, M, Oman, LD, Pitari, G, Plummer, DA, Revell, LE, Saint-Martin, D, Schofield, R, Stenke, A, Stone, K, Sudo, K, Tanaka, TY, Tilmes, S, Yamashita, Y, Yoshida, K, Zeng, G, Morgenstern, O, Hegglin, MI, Rozanov, E, O'Connor, FM, Abraham, NL, Akiyoshi, H, Archibald, AT, Bekki, S, Butchart, N, Chipperfield, MP, Deushi, M, Dhomse, SS, Garcia, RR, Hardiman, SC, Horowitz, LW, Joeckel, P, Josse, B, Kinnison, D, Lin, M, Mancini, E, Manyin, ME, Marchand, M, Marecal, V, Michou, M, Oman, LD, Pitari, G, Plummer, DA, Revell, LE, Saint-Martin, D, Schofield, R, Stenke, A, Stone, K, Sudo, K, Tanaka, TY, Tilmes, S, Yamashita, Y, Yoshida, K, and Zeng, G
- Abstract
We present an overview of state-of-the-art chemistry–climate and chemistry transport models that are used within phase 1 of the Chemistry–Climate Model Initiative (CCMI-1). The CCMI aims to conduct a detailed evaluation of participating models using process-oriented diagnostics derived from observations in order to gain confidence in the models' projections of the stratospheric ozone layer, tropospheric composition, air quality, where applicable global climate change, and the interactions between them. Interpretation of these diagnostics requires detailed knowledge of the radiative, chemical, dynamical, and physical processes incorporated in the models. Also an understanding of the degree to which CCMI-1 recommendations for simulations have been followed is necessary to understand model responses to anthropogenic and natural forcing and also to explain inter-model differences. This becomes even more important given the ongoing development and the ever-growing complexity of these models. This paper also provides an overview of the available CCMI-1 simulations with the aim of informing CCMI data users.
- Published
- 2017
5. Radiographic evaluation of patellar ligament length after tibial plateau leveling osteotonny in dogs.
- Author
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Beaty, Brenda L., Jay, Maureen R., Mattoon, John S., Gilbert, Peter J., and Tanaka, Ty T.
- Subjects
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RADIOGRAPHY , *PATELLAR tendon , *TIBIAL plateau fractures , *OSTEOTOMY , *DOGS - Abstract
OBJECTIVE To radiographically cooipare patellar ligament length (PLL) in dogs undergoing tibia! plateau leveling osteotomy (TPLO) for unilateral cranial cruciate ligament rupture at preoperative, postoperative, and follow-up evaluations. ANIMALS 105 dogs that underwent TPLO for unilateral cranial cruciate ligament rupture at a referral veterinary hospital from October I, 2008, through November 30, 2017. PROCEDURES Medical records were reviewed to obtain information on dog signalment, surgical procedure, and radiographically measured PLL at preoperative, postoperative, and follow-up evaluations. RESULTS Dogs undergoing TPLO had a shorter PLL at the postoperative and follow-up evaluations, compared with the PLL at the preoperative evaluation. Mean ± SD overall unadjusted PLL decreased significantly by 2.3 ± 3.4% between the preoperative and postoperative evaluation and by 2.8 ± 3.9% between the preoperative and follow-up evaluation. The PLL did not differ significantly between the postoperative and follow-up evaluation; mean PLL decreased by 0.4 ± 3.8% between the postoperative and follow-up evaluation. CONCLUSIONS AND CLINICAL RELEVANCE The PLL was shorter after TPLO in dogs, which was similar to changes observed for humans after high tibial osteotomy procedures. Further evaluation of clinical assessments, joint mobility, ultrasonographic assessments, and kinematic results are needed to determine the relevance of the PLL and whether a decrease in ligament length results in decreased mobility and persistent lameness in dogs, as has been reported for humans. [ABSTRACT FROM AUTHOR]
- Published
- 2019
6. Dust Vortex in the Taklimakan Desert by Himawari-8 High Frequency and Resolution Observation.
- Author
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Yumimoto K, Kajino M, Tanaka TY, and Uno I
- Abstract
The Taklimakan Desert is known to be one of the world's major sources of aeolian dust particles. Continuous images with 10-min temporal and 2-km spatial resolutions from a new-generation geostationary meteorological satellite captured the lifecycle (generation, evolution and outflow) of a previously unrecognized type of Taklimakan dust storm. The dust storm showed an anti-clockwise spiral structure and a clear core and behaved like a "dust vortex". From image analysis, the horizontal scale and temporal lifetime of the dust vortex were estimated to be 600 km and 36 hours, respectively. We found that a strong pressure trough (cut-off low), along with a cold air mass located on the northwestern side of the Taklimakan Desert and the high mountains surrounding the Taklimakan Desert, played important roles in the formation and evolution of the dust vortex.
- Published
- 2019
- Full Text
- View/download PDF
7. Ultraviolet radiation modelling using output from the Chemistry Climate Model Initiative.
- Author
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Lamy K, Portafaix T, Josse B, Brogniez C, Godin-Beekmann S, Bencherif H, Revell L, Akiyoshi H, Bekki S, Hegglin MI, Jöckel P, Kirner O, Marecal V, Morgenstern O, Stenke A, Zeng G, Abraham NL, Archibald AT, Butchart N, Chipperfield MP, Di Genova G, Deushi M, Dhomse SS, Hu RM, Kinnison D, Michou M, O'Connor FM, Oman LD, Pitari G, Plummer DA, Pyle JA, Rozanov E, Saint-Martin D, Sudo K, Tanaka TY, Visioni D, and Yoshida K
- Abstract
We have derived values of the Ultraviolet Index (UVI) at solar noon using the Tropospheric Ultraviolet Model (TUV) driven by ozone, temperature and aerosol fields from climate simulations of the first phase of the Chemistry-Climate Model Initiative (CCMI-1). Since clouds remain one of the largest uncertainties in climate projections, we simulated only the clear-sky UVI. We compared the modelled UVI climatologies against present-day climatological values of UVI derived from both satellite data (the OMI-Aura OMUVBd product) and ground-based measurements (from the NDACC network). Depending on the region, relative differences between the UVI obtained from CCMI/TUV calculations and the ground-based measurements ranged between -5.9% and 10.6%. We then calculated the UVI evolution throughout the 21st century for the four Representative Concentration Pathways (RCPs 2.6, 4.5, 6.0 and 8.5). Compared to 1960s values, we found an average increase in the UVI in 2100 (of 2-4%) in the tropical belt (30°N-30°S). For the mid-latitudes, we observed a 1.8 to 3.4 % increase in the Southern Hemisphere for RCP 2.6, 4.5 and 6.0, and found a 2.3% decrease in RCP 8.5. Higher increases in UVI are projected in the Northern Hemisphere except for RCP 8.5. At high latitudes, ozone recovery is well identified and induces a complete return of mean UVI levels to 1960 values for RCP 8.5 in the Southern Hemisphere. In the Northern Hemisphere, UVI levels in 2100 are higher by 0.5 to 5.5% for RCP 2.6, 4.5 and 6.0 and they are lower by 7.9% for RCP 8.5. We analysed the impacts of greenhouse gases (GHGs) and ozone-depleting substances (ODSs) on UVI from 1960 by comparing CCMI sensitivity simulations (1960-2100) with fixed GHGs or ODSs at their respective 1960 levels. As expected with ODS fixed at their 1960 levels, there is no large decrease in ozone levels and consequently no sudden increase in UVI levels. With fixed GHG, we observed a delayed return of ozone to 1960 values, with a corresponding pattern of change observed on UVI, and looking at the UVI difference between 2090s values and 1960s values, we found an 8 % increase in the tropical belt during the summer of each hemisphere. Finally we show that, while in the Southern Hemisphere the UVI is mainly driven by total ozone column, in the Northern Hemisphere both total ozone column and aerosol optical depth drive UVI levels, with aerosol optical depth having twice as much influence on the UVI as total ozone column does.
- Published
- 2019
- Full Text
- View/download PDF
8. Use of a size-resolved 1-D resuspension scheme to evaluate resuspended radioactive material associated with mineral dust particles from the ground surface.
- Author
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Ishizuka M, Mikami M, Tanaka TY, Igarashi Y, Kita K, Yamada Y, Yoshida N, Toyoda S, Satou Y, Kinase T, Ninomiya K, and Shinohara A
- Subjects
- Dust, Japan, Minerals, Particle Size, Radiation Monitoring, Cesium Radioisotopes analysis, Fukushima Nuclear Accident, Models, Theoretical, Soil chemistry, Soil Pollutants, Radioactive analysis
- Abstract
A size-resolved, one-dimensional resuspension scheme for soil particles from the ground surface is proposed to evaluate the concentration of radioactivity in the atmosphere due to the secondary emission of radioactive material. The particle size distributions of radioactive particles at a sampling point were measured and compared with the results evaluated by the scheme using four different soil textures: sand, loamy sand, sandy loam, and silty loam. For sandy loam and silty loam, the results were in good agreement with the size-resolved atmospheric radioactivity concentrations observed at a school ground in Tsushima District, Namie Town, Fukushima, which was heavily contaminated after the Fukushima Dai-ichi Nuclear Power Plant accident in March 2011. Though various assumptions were incorporated into both the scheme and evaluation conditions, this study shows that the proposed scheme can be applied to evaluate secondary emissions caused by aeolian resuspension of radioactive materials associated with mineral dust particles from the ground surface. The results underscore the importance of taking soil texture into account when evaluating the concentrations of resuspended, size-resolved atmospheric radioactivity., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
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