GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Seasonal ventilation of the stratosphere: Robust diagnostics from one‐way flux distributions
    American Geophysical Union (AGU) ; 2014
    In:  Journal of Geophysical Research: Atmospheres Vol. 119, No. 1 ( 2014-01-16), p. 293-306
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 119, No. 1 ( 2014-01-16), p. 293-306
    Abstract: Seasonal ventilation of the stratosphere is quantified using flux distributions Cross tropopause fluxes depend sensitively on entry time at tropical tropopause Mean stratospheric residence times are 5.1 and 5.7 years in the NH and in the SH
    Type of Medium: Online Resource
    ISSN: 2169-897X , 2169-8996
    URL: Issue
    URL: Article
    DOI: 10.1002/jgrd.v119.1
    DOI: 10.1002/2013JD020213
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 2014
    detail.hit.zdb_id: 710256-2
    detail.hit.zdb_id: 2016800-7
    detail.hit.zdb_id: 2969341-X
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Air-mass Origin in the Arctic. Part II: Response to Increases in Greenhouse Gases
    American Meteorological Society ; 2015
    In:  Journal of Climate Vol. 28, No. 23 ( 2015-12-01), p. 9105-9120
    Details
    In: Journal of Climate, American Meteorological Society, Vol. 28, No. 23 ( 2015-12-01), p. 9105-9120
    Abstract: Future changes in transport from Northern Hemisphere (NH) midlatitudes into the Arctic are examined using rigorously defined air-mass fractions that partition air in the Arctic according to where it last had contact with the planetary boundary layer (PBL). Boreal winter (December–February) and summer (June–August) air-mass fraction climatologies are calculated for the modeled climate of the Goddard Earth Observing System Chemistry–Climate Model (GEOSCCM) forced with the end-of-twenty-first century greenhouse gases and ozone-depleting substances. The modeled projections indicate that the fraction of air in the Arctic that last contacted the PBL over NH midlatitudes (or air of “midlatitude origin”) will increase by about 10% in both winter and summer. The projected increases during winter are largest in the upper and middle Arctic troposphere, where they reflect an upward and poleward shift in the transient eddy meridional wind, a robust dynamical response among comprehensive climate models. The boreal winter response is dominated by (~5%–10%) increases in the air-mass fractions originating over the eastern Pacific and the Atlantic, while the response in boreal summer mainly reflects (~5%) increases in air of Asian and North American origin. The results herein suggest that future changes in transport from midlatitudes may impact the composition—and, hence, radiative budget—in the Arctic, independent of changes in emissions.
    Type of Medium: Online Resource
    ISSN: 0894-8755 , 1520-0442
    URL: Article
    DOI: 10.1175/JCLI-D-15-0296.1
    RVK:
    UA 4548
    Language: English
    Publisher: American Meteorological Society
    Publication Date: 2015
    detail.hit.zdb_id: 246750-1
    detail.hit.zdb_id: 2021723-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Large‐Scale Atmospheric Transport in GEOS Replay Simulations
    American Geophysical Union (AGU) ; 2017
    In:  Journal of Advances in Modeling Earth Systems Vol. 9, No. 7 ( 2017-11), p. 2545-2560
    Details
    In: Journal of Advances in Modeling Earth Systems, American Geophysical Union (AGU), Vol. 9, No. 7 ( 2017-11), p. 2545-2560
    Abstract: GEOS replay simulations produce credible large‐scale stratospheric and tropospheric transport for use in studies of atmospheric composition Simulations constrained with analysis fields produce stratospheric mean ages that are too young, versus when assimilated fields are used By comparison, large‐scale tropospheric transport properties are relatively insensitive to whether analysis or assimilated fields are used
    Type of Medium: Online Resource
    ISSN: 1942-2466 , 1942-2466
    URL: Issue
    URL: Article
    DOI: 10.1002/jame.v9.7
    DOI: 10.1002/2017MS001053
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 2017
    detail.hit.zdb_id: 2462132-8
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Large-scale tropospheric transport in the Chemistry–Climate Model Initiative (CCMI) simulations
    Copernicus GmbH ; 2018
    In:  Atmospheric Chemistry and Physics Vol. 18, No. 10 ( 2018-05-25), p. 7217-7235
    Details
    In: Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 18, No. 10 ( 2018-05-25), p. 7217-7235
    Abstract: 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.
    Type of Medium: Online Resource
    ISSN: 1680-7324
    URL: Article
    URL: Article
    DOI: 10.5194/acp-18-7217-2018
    DOI: 10.5194/acp-18-7217-2018-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2018
    detail.hit.zdb_id: 2092549-9
    detail.hit.zdb_id: 2069847-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Recent Decline in Extratropical Lower Stratospheric Ozone Attributed to Circulation Changes
    American Geophysical Union (AGU) ; 2018
    In:  Geophysical Research Letters Vol. 45, No. 10 ( 2018-05-28), p. 5166-5176
    Details
    In: Geophysical Research Letters, American Geophysical Union (AGU), Vol. 45, No. 10 ( 2018-05-28), p. 5166-5176
    Abstract: The MERRA‐2 reanalysis shows negative ozone trends in the extratropical lower stratosphere between 1998 and 2016 These ozone trends are likely a result of enhanced two‐way transport between the Tropics and the extratropics This study is the first to use bias‐corrected reanalysis ozone to assess and attribute vertically resolved ozone trends
    Type of Medium: Online Resource
    ISSN: 0094-8276 , 1944-8007
    URL: Article
    DOI: 10.1029/2018GL077406
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 2018
    detail.hit.zdb_id: 2021599-X
    detail.hit.zdb_id: 7403-2
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Mechanisms Linked to Recent Ozone Decreases in the Northern Hemisphere Lower Stratosphere
    American Geophysical Union (AGU) ; 2020
    In:  Journal of Geophysical Research: Atmospheres Vol. 125, No. 9 ( 2020-05-16)
    Details
    In: Journal of Geophysical Research: Atmospheres, American Geophysical Union (AGU), Vol. 125, No. 9 ( 2020-05-16)
    Abstract: Free‐running and MERRA‐2‐constrained GEOS runs are used to identify mechanisms for ozone decreases in the lower stratosphere over 1998–2018 Analysis of an idealized e90 tracer indicates that ozone decreases are associated with a poleward expansion of the residual mean circulation Free‐running GEOS simulations produce weaker residual circulation—and associated ozone—changes over 1998–2018, compared to reanalyses
    Type of Medium: Online Resource
    ISSN: 2169-897X , 2169-8996
    URL: Article
    DOI: 10.1029/2019JD031631
    Language: English
    Publisher: American Geophysical Union (AGU)
    Publication Date: 2020
    detail.hit.zdb_id: 710256-2
    detail.hit.zdb_id: 2016800-7
    detail.hit.zdb_id: 2969341-X
    SSG: 16,13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Airmass Origin in the Arctic. Part I: Seasonality
    American Meteorological Society ; 2015
    In:  Journal of Climate Vol. 28, No. 12 ( 2015-06-15), p. 4997-5014
    Details
    In: Journal of Climate, American Meteorological Society, Vol. 28, No. 12 ( 2015-06-15), p. 4997-5014
    Abstract: The first climatology of airmass origin in the Arctic is presented in terms of rigorously defined airmass fractions that partition air according to where it last contacted the planetary boundary layer (PBL). Results from a present-day climate integration of the Goddard Earth Observing System Chemistry–Climate Model (GEOSCCM) reveal that the majority of air in the Arctic below 700 mb last contacted the PBL poleward of 60°N. By comparison, 62% (±0.8%) of the air above 700 mb originates over Northern Hemisphere midlatitudes (i.e., “midlatitude air”). Seasonal variations in the airmass fractions above 700 mb reveal that during boreal winter air from midlatitudes originates primarily over the oceans, with 26% (±1.9%) last contacting the PBL over the eastern Pacific, 21% (±0.87%) over the Atlantic, and 16% (±1.2%) over the western Pacific. During summer, by comparison, midlatitude air originates primarily over land, overwhelmingly so over Asia [41% (±1.0%)] and, to a lesser extent, over North America [24% (±1.5%)] . Seasonal variations in the airmass fractions are interpreted in terms of changes in the large-scale ventilation of the midlatitude boundary layer and the midlatitude tropospheric jet.
    Type of Medium: Online Resource
    ISSN: 0894-8755 , 1520-0442
    URL: Article
    DOI: 10.1175/JCLI-D-14-00720.1
    RVK:
    UA 4548
    Language: English
    Publisher: American Meteorological Society
    Publication Date: 2015
    detail.hit.zdb_id: 246750-1
    detail.hit.zdb_id: 2021723-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Future trends in stratosphere-to-troposphere transport in CCMI models
    Copernicus GmbH ; 2020
    In:  Atmospheric Chemistry and Physics Vol. 20, No. 11 ( 2020-06-11), p. 6883-6901
    Details
    In: Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 20, No. 11 ( 2020-06-11), p. 6883-6901
    Abstract: Abstract. One of the key questions in the air quality and climate sciences is how tropospheric ozone concentrations will change in the future. This will depend on two factors: changes in stratosphere-to-troposphere transport (STT) and changes in tropospheric chemistry. Here we aim to identify robust changes in STT using simulations from the Chemistry Climate Model Initiative (CCMI) under a common climate change scenario (RCP6.0). We use two idealized stratospheric tracers to isolate changes in transport: stratospheric ozone (O3S), which is exactly like ozone but has no chemical sources in the troposphere, and st80, a passive tracer with fixed volume mixing ratio in the stratosphere. We find a robust increase in the tropospheric columns of these two tracers across the models. In particular, stratospheric ozone in the troposphere is projected to increase 10 %–16 % by the end of the 21st century in the RCP6.0 scenario. Future STT is enhanced in the subtropics due to the strengthening of the shallow branch of the Brewer–Dobson circulation (BDC) in the lower stratosphere and of the upper part of the Hadley cell in the upper troposphere. The acceleration of the deep branch of the BDC in the Northern Hemisphere (NH) and changes in eddy transport contribute to increased STT at high latitudes. These STT trends are caused by greenhouse gas (GHG) increases, while phasing out of ozone-depleting substances (ODS) does not lead to robust transport changes. Nevertheless, the decline of ODS increases the reservoir of ozone in the lower stratosphere, which results in enhanced STT of O3S at middle and high latitudes. A higher emission scenario (RCP8.5) produces stronger STT trends, with increases in tropospheric column O3S more than 3 times larger than those in the RCP6.0 scenario by the end of the 21st century.
    Type of Medium: Online Resource
    ISSN: 1680-7324
    URL: Article
    DOI: 10.5194/acp-20-6883-2020
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2020
    detail.hit.zdb_id: 2092549-9
    detail.hit.zdb_id: 2069847-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...