High-level warmings and total ozone over a tropical region

Abstract. In the present paper, we have calculated the outgoing longwave radiation at the top of the atmosphere (OLR at TOA) using a deterministic radiation transfer model, cloud data from ISCCP-D, and atmospheric temperature and humidity data from NCEP/NCAR reanalysis, for the seventeen-year period 1984-2000. We constructed anomaly time-series of the OLR at TOA, as well as of all of the key input climatological data, averaged in the tropical region between 20°N and 20°S. We compared the anomaly time-series of the model calculated OLR at TOA with that obtained from the ERBE S-10N (WFOV NF edition 2) non-scanner measurements. The model results display very similar seasonal and inter-annual variability as the ERBS data, and indicate a decadal increase of OLR at TOA of 1.9±0.2Wm-2/decade, which is lower than that displayed by the ERBS time-series (3.5±0.3Wm-2). Analysis of the inter-annual and long-term variability of the various parameters determining the OLR at TOA, showed that the most important contribution to the observed trend comes from a decrease in high-level cloud cover over the period 1984-2000, followed by an apparent drying of the upper troposphere and a decrease in low-level cloudiness. Opposite but small trends are introduced by a decrease in low-level cloud top pressure, an apparent cooling of the lower stratosphere (at the 50mbar level) and a small decadal increase in mid-level cloud cover.

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Comparison of GTO-ECV and adjusted MERRA-2 total ozone columns from the last 2 decades and assessment of interannual variability

Atmospheric Measurement Techniques ◽

10.5194/amt-13-1633-2020 ◽

2020 ◽

Vol 13 (3) ◽

pp. 1633-1654

Author(s):

Melanie Coldewey-Egbers ◽

Diego G. Loyola ◽

Gordon Labow ◽

Stacey M. Frith

Keyword(s):

Interannual Variability ◽

Total Ozone ◽

Southern Oscillation ◽

Mean Difference ◽

Tropical Region ◽

Ozone Monitoring Instrument ◽

Spatial And Temporal Patterns ◽

Quasi Biennial Oscillation ◽

The Mean ◽

Ozone Monitoring

Abstract. In this study we compare the satellite-based Global Ozone Monitoring Experiment (GOME)-type Total Ozone Essential Climate Variable (GTO-ECV) record, generated as part of the European Space Agency's Climate Change Initiative (ESA-CCI) ozone project, with the adjusted total ozone product from the Modern Era Retrospective Analysis for Research and Applications version 2 (adjusted MERRA-2) reanalysis, produced at the National Aeronautics and Space Administration (NASA) Global Modeling and Assimilation Office (GMAO). Total ozone columns and associated standard deviations show a very good agreement in terms of both spatial and temporal patterns during their 23-year overlap period from July 1995 to December 2018. The mean difference between adjusted MERRA-2 and GTO-ECV 5∘×5∘ monthly mean total ozone columns is -0.9±1.5 %. A small discontinuity in the deviations is detected in October 2004, when data from the Ozone Monitoring Instrument (OMI) were ingested in the GTO-ECV and adjusted MERRA-2 data records. This induces a small overall negative drift in the differences for almost all latitude bands, which, however, does not exceed 1 % per decade. The mean difference for the period prior to October 2004 is -0.5±1.7 %, whereas the difference is -1.0±1.1 % for the period from October 2004 to December 2018. The variability in the differences is considerably reduced in the period after 2004 due to a significant increase in data coverage and sampling. In the tropical region, the differences indicate a slight zonal variability with negative deviations over the Atlantic, Africa, and the Indian Ocean and positive deviations over the Pacific. Ozone anomalies and the distribution of their statistical moments indicate a very high correlation among both data records as to the temporal and spatial structures. Furthermore, we evaluate the consistency of the data sets by means of an empirical orthogonal function (EOF) analysis. The interannual variability is assessed in the tropics, and both GTO-ECV and adjusted MERRA-2 exhibit a remarkable agreement with respect to the derived patterns. The first four EOFs can be attributed to different modes of interannual climate variability, and correlations with the Quasi-Biennial Oscillation (QBO), the El Niño–Southern Oscillation (ENSO) signal, and the solar cycle were found.

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On the decadal increase in the tropical mean outgoing longwave radiation for the period 1984–2000

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-4-2727-2004 ◽

2004 ◽

Vol 4 (3) ◽

pp. 2727-2745

Author(s):

D. Hatzidimitriou ◽

I. Vardavas ◽

K. G. Pavlakis ◽

N. Hatzianastassiou ◽

C. Matsoukas ◽

...

Keyword(s):

Time Series ◽

Outgoing Longwave Radiation ◽

Cloud Cover ◽

Longwave Radiation ◽

Atmospheric Temperature ◽

Tropical Region ◽

Transfer Model ◽

Cloud Data ◽

Low Level ◽

High Level

Abstract. In the present paper, we have calculated the outgoing longwave radiation at the top of the atmosphere (OLR at TOA) using a deterministic radiation transfer model, cloud data from ISCCP-D, and atmospheric temperature and humidity data from NCEP/NCAR reanalysis, for the seventeen-year period 1984–2000. We constructed anomaly time-series of the OLR at TOA, as well as of all of the key input climatological data, averaged in the tropical region between 20° N and 20° S. We compared the anomaly time-series of the model calculated OLR at TOA with that obtained from the ERBE S-10N (WFOV NF edition 2) non-scanner measurements. The model results display very similar seasonal and inter-annual variability as the ERBS data, and indicate a decadal increase of OLR at TOA of 1.9±0.2 Wm−2/decade, which is lower than that displayed by the ERBS time-series (3.5±0.3 Wm−2). Analysis of the inter-annual and long-term variability of the various parameters determining the OLR at TOA, showed that the most important contribution to the observed trend comes from a decrease in high-level cloud cover over the period 1984–2000, followed by an apparent drying of the upper troposphere and a decrease in low-level cloudiness. Opposite but small trends are introduced by a decrease in low-level cloud top pressure, an apparent cooling of the lower stratosphere (at the 50 mbar level) and a small decadal increase in mid-level cloud cover.

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Seagrass Cover On The Island Of Manado Tua, Bunaken Kepulauan District, Manado City

JURNAL PERIKANAN DAN KELAUTAN TROPIS ◽

10.35800/jpkt.11.1.2020.29888 ◽

2020 ◽

Vol 11 (1) ◽

pp. 16

Author(s):

Efraim Bulele ◽

Ferdinand F. Tilaar ◽

Maartianus S. Baroleh ◽

Ridwan Lasabuda ◽

Darus S. J. Paransa ◽

...

Keyword(s):

Coastal Waters ◽

Tidal Wave ◽

The Other ◽

Tropical Region ◽

Thalassia Hemprichii ◽

High Rise ◽

Seagrass Cover ◽

High Level ◽

The City ◽

High Chance

The lamun is a high level of vegetation that lives in the sub-tropical region. The lamun has a high chance of survival in southeast Asia. In Indonesia, details of the largest tidal wave in the east are so much for research about lamun, one of which is information about the current research project of the lamun ocean in old manado island. The study was intended to obtain information about the percentage of lamun caps in the coastal waters of old manando island. Research is based on the old island of manado, the bunaken islands district, the city of manado was completed in the second week of December. To find out which artic percentage patch on Manado Tua island, a type of seagrass Thalassia hemprichii and Enhalus acorides, 71% frame presentation. The total 33 square, the 23 squares is Enhalus acorides and 2 of them Thalassia hemprichii while the other 8 squares are occupied by 2 types seagrass. the other net value of the current was 3,4 cm/s, a precentage of current velocity 100%, and when the water rose 0,21 m, whereas a high rise of 2,17 m, the salinity rate of Manado island is 35 ‰, three times that of salinity measurement was achived in lowest scores 26⁰C and the highest figure 29⁰C, the caostal waters substrat Manado tua island to which is sand, rocky, coral reef mixes, sand blends with gravel.Key words : seagrass, percent of cover, Manado tua island ABSTRAKLamun adalah tumbuhan tingkat tinggi yang hidup di wilayah sub-tropis. Lamun mempunyai peluang hidup yang tinggi di kawasan Asia Tenggara. Di indonesia rincian luasan lamun terbesar berada dibagian timur sehingga masih banyak kajian penelitian yang harus diungkapkan tentang Lamun, salah satunya informasi mengenai presentase tutupan Lamun. penelitian kali ini mengenai tutupan lamun di perairan pantai pulau Manado Tua. Penelitian ini bertujuan untuk mendapatkan informasi tentang persentase tutupan lamun di perairan pantai pulau Manando tua. Penelitian berlokasi di Pulau Manado tua, Kecamatan Bunaken Kepulauan, Kota Manado dilaksanakan pada minggu kedua bulan Desember. Untuk mengetahui persantese tutupan lamun di pulau Manado Tua menggunakan metode Line transeck . Hasil penelitian di Pulau Manado tua, jenis lamun yaitu: Thalassia hemprichii dan Enhalus acorides, presentase tutupan lamun 71,4%. Total 33 kuadrat, 23 diantarnya adalah Enhalus acorides dan 2 diantaranya Thalassia hemprichii sedangkan 8 kuadrat lainnya ditempati 2 jenis lamun. Parameter biofisik lainnya yang didapat, kecepatan arus rata-rata pengukuran 3 stasiun yaitu 3,4 cm/s, persentase kecepatan arus 100%, kedalam saat air surut 0,21 m sedangkan ketika pasang tertinggi 2,17 m, Pengukuran salinitas di peraiaran pantai pulau Manado Tua diperoleh angka kadar salinitas yaitu 35 ‰, pengukuran suhu dilakukan sebanyak tiga kali dan di peroleh angka terendah 26⁰C dan angka paling tinggi 29⁰C, Substrat perairan pantai pulau Manado yang di temui yaitu berpasir, berbatu, bercampur terumbu karang, pasir bercampur dengan kerikil. merskipun tingkat keragaman jenis tidak tinggi namun penelitian di perairan pantai pulau Manado Tua menujukan bahwa persentase tutupan lamun berada dalam kategori Baik (≥ 60%). Kata kunci : Lamun, Persentase tutupan, Pulau Manado tua

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Estudo numérico e observacional de um evento de diminuição da coluna total de ozônio de origem tropical no Sul do Brasil

Ciência e Natura ◽

10.5902/2179460x55305 ◽

2020 ◽

Vol 42 ◽

pp. e5

Author(s):

Lissette Guzmán ◽

Vagner Anabor ◽

Luiz Angelo Steffenel ◽

Damaris Kirsch Pinheiro

Keyword(s):

Total Ozone ◽

Depletion Region ◽

Tropical Region ◽

Study Region ◽

Total Ozone Column ◽

Horizontal Transport ◽

Stratospheric Intrusion ◽

Ozone Column ◽

Different Levels ◽

South Brazil

A depletion event of 11% of the total ozone column over South Brazil was analyzed from observational data and numerical simulations. The meteorological fields resulting from the simulation did not show the presence of subtropical or polar jets over the study region. The real and simulated soundings showed the dryness at high and low tropospheric levels, pointing a stratospheric intrusion. The total ozone column values from ERA-5 reanalyses showed the maintenance of a region with low total ozone values in tropical latitudes and its advance over the study region, before and during the depletion event. The isentropic retro-trajectories of air parcels at different levels, obtained with the Hybrid Single Lagrangian Integrated Trajectory Model (HYSPLIT), confirmed the zonal transport from the tropical region over Southern Brazil. A combination of a cyclonic circulation at the 850 K stratospheric isentropic level and an intense anticyclonic circulation at the 440 K tropospheric level, over the depletion region, was identified as responsible for the tropopause lift and horizontal transport of ozone-rich air out of the column.

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Comparison of GTO-ECV and Adjusted-MERRA total ozone columns from the last two decades and assessment of interannual variability

10.5194/amt-2019-297 ◽

2019 ◽

Author(s):

Melanie Coldewey-Egbers ◽

Diego Loyola ◽

Gordon Labow ◽

Stacey Frith

Keyword(s):

Interannual Variability ◽

Total Ozone ◽

Southern Oscillation ◽

Mean Difference ◽

Tropical Region ◽

Ozone Monitoring Instrument ◽

Spatial And Temporal Patterns ◽

Quasi Biennial Oscillation ◽

The Mean ◽

The Difference

Abstract. In this study we compare the satellite-based GOME-type Total Ozone Essential Climate Variable (GTO-ECV) record, generated as part of the European Space Agency's Climate Change Initiative (ESA-CCI) ozone project, with the Adjusted total ozone product from the Modern Era Retrospective Analysis for Research and Applications version 2 (Adjusted-MERRA) reanalysis, produced at the National Aeronautics and Space Administration (NASA) Global Modeling and Assimilation Office (GMAO). Total ozone columns and associated standard deviations show a very good agreement in terms of both spatial and temporal patterns during their 23-year overlap period from July 1995 to December 2018. The mean difference between Adjusted-MERRA and GTO-ECV 5° × 5° monthly mean total ozone columns is −0.9 ± 1.5 %. A small discontinuity in the deviations is detected in October 2004 when data from the Ozone Monitoring Instrument (OMI) was ingested in the GTO-ECV data record. This induces a small overall negative drift in the differences for almost all latitude bands, which, however, does not exceed 1 % decade−1. The mean difference for the period prior to October 2004 is −0.5 ± 1.7 %, whereas the difference is −1.1 ± 1.2 % for the second period. The variability in the differences is considerably reduced in the later period due to significant increase in data coverage and sampling. In the tropical region the differences indicate a slight zonal variability with negative deviations over the Atlantic, Africa, and the Indian Ocean, and positive deviations over the Pacific. Ozone anomalies and the distribution of their statistical moments indicate a very high correlation among both data records as to the temporal and spatial structures. Furthermore, we evaluate the consistency of the datasets by means of an empirical orthogonal function (EOF) analysis. The interannual variability is assessed in the tropics, and both GTO-ECV and Adjusted-MERRA exhibit a remarkable agreement with respect to the derived patterns. The first four EOFs can be attributed to different modes of interannual climate variability, and correlations with the Quasi-Biennial Oscillation (QBO), the El Niño Southern Oscillation (ENSO) signal, and the solar cycle were found.

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Transcription factor/DNA interactions visualized by electron spectroscopic imaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122654 ◽

1992 ◽

Vol 50 (1) ◽

pp. 450-451

Author(s):

David P. Bazett-Jones ◽

Mark L. Brown

Keyword(s):

Transcription Factor ◽

Dna Sequences ◽

Transcription Initiation ◽

Molecular Mechanisms ◽

Phosphorus Content ◽

Spectroscopic Imaging ◽

Electron Spectroscopic Imaging ◽

Dna Backbone ◽

Two Parameters ◽

High Level

A multisubunit RNA polymerase enzyme is ultimately responsible for transcription initiation and elongation of RNA, but recognition of the proper start site by the enzyme is regulated by general, temporal and gene-specific trans-factors interacting at promoter and enhancer DNA sequences. To understand the molecular mechanisms which precisely regulate the transcription initiation event, it is crucial to elucidate the structure of the transcription factor/DNA complexes involved. Electron spectroscopic imaging (ESI) provides the opportunity to visualize individual DNA molecules. Enhancement of DNA contrast with ESI is accomplished by imaging with electrons that have interacted with inner shell electrons of phosphorus in the DNA backbone. Phosphorus detection at this intermediately high level of resolution (≈lnm) permits selective imaging of the DNA, to determine whether the protein factors compact, bend or wrap the DNA. Simultaneously, mass analysis and phosphorus content can be measured quantitatively, using adjacent DNA or tobacco mosaic virus (TMV) as mass and phosphorus standards. These two parameters provide stoichiometric information relating the ratios of protein:DNA content.

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Advances in Stem Instrumentation for Biology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180562 ◽

1990 ◽

Vol 48 (1) ◽

pp. 362-363

Author(s):

J. S. Wall

Keyword(s):

Scanning Transmission Electron Microscope ◽

Carbon Films ◽

Specimen Preparation ◽

Material Deposition ◽

Active User ◽

Percent Improvement ◽

Scanning Transmission ◽

The Moment ◽

Film Substrate ◽

High Level

The forte of the Scanning transmission Electron Microscope (STEM) is high resolution imaging with high contrast on thin specimens, as demonstrated by visualization of single heavy atoms. of equal importance for biology is the efficient utilization of all available signals, permitting low dose imaging of unstained single molecules such as DNA.Our work at Brookhaven has concentrated on: 1) design and construction of instruments optimized for a narrow range of biological applications and 2) use of such instruments in a very active user/collaborator program. Therefore our program is highly interactive with a strong emphasis on producing results which are interpretable with a high level of confidence.The major challenge we face at the moment is specimen preparation. The resolution of the STEM is better than 2.5 A, but measurements of resolution vs. dose level off at a resolution of 20 A at a dose of 10 el/A2 on a well-behaved biological specimen such as TMV (tobacco mosaic virus). To track down this problem we are examining all aspects of specimen preparation: purification of biological material, deposition on the thin film substrate, washing, fast freezing and freeze drying. As we attempt to improve our equipment/technique, we use image analysis of TMV internal controls included in all STEM samples as a monitor sensitive enough to detect even a few percent improvement. For delicate specimens, carbon films can be very harsh-leading to disruption of the sample. Therefore we are developing conducting polymer films as alternative substrates, as described elsewhere in these Proceedings. For specimen preparation studies, we have identified (from our user/collaborator program ) a variety of “canary” specimens, each uniquely sensitive to one particular aspect of sample preparation, so we can attempt to separate the variables involved.

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A Questionnaire Survey of Current Rehabilitation Practices for Adults With Normal Hearing Sensitivity Who Experience Auditory Difficulties

American Journal of Audiology ◽

10.1044/2020_aja-20-00027 ◽

2020 ◽

Vol 29 (4) ◽

pp. 738-761

Author(s):

Tess K. Koerner ◽

Melissa A. Papesh ◽

Frederick J. Gallun

Keyword(s):

Hearing Aids ◽

Questionnaire Survey ◽

Patient Population ◽

Clinical Care ◽

Normal Hearing ◽

Auditory Training ◽

Training Methods ◽

Hearing Sensitivity ◽

Considerable Benefit ◽

High Level

Purpose A questionnaire survey was conducted to collect information from clinical audiologists about rehabilitation options for adult patients who report significant auditory difficulties despite having normal or near-normal hearing sensitivity. This work aimed to provide more information about what audiologists are currently doing in the clinic to manage auditory difficulties in this patient population and their views on the efficacy of recommended rehabilitation methods. Method A questionnaire survey containing multiple-choice and open-ended questions was developed and disseminated online. Invitations to participate were delivered via e-mail listservs and through business cards provided at annual audiology conferences. All responses were anonymous at the time of data collection. Results Responses were collected from 209 participants. The majority of participants reported seeing at least one normal-hearing patient per month who reported significant communication difficulties. However, few respondents indicated that their location had specific protocols for the treatment of these patients. Counseling was reported as the most frequent rehabilitation method, but results revealed that audiologists across various work settings are also successfully starting to fit patients with mild-gain hearing aids. Responses indicated that patient compliance with computer-based auditory training methods was regarded as low, with patients generally preferring device-based rehabilitation options. Conclusions Results from this questionnaire survey strongly suggest that audiologists frequently see normal-hearing patients who report auditory difficulties, but that few clinicians are equipped with established protocols for diagnosis and management. While many feel that mild-gain hearing aids provide considerable benefit for these patients, very little research has been conducted to date to support the use of hearing aids or other rehabilitation options for this unique patient population. This study reveals the critical need for additional research to establish evidence-based practice guidelines that will empower clinicians to provide a high level of clinical care and effective rehabilitation strategies to these patients.

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