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MEaSUREs GOZCARDS stratospheric data records update

Data products are now available of ozone, water vapour, nitric acid and nitrous oxide.

The Goddard Earth Sciences Data and Information Services Center (GES DISC), in collaboration with Principal Investigator Lucien Froidevaux, is pleased to announce the release of the ozone (O3), water vapor (H2O), nitric acid (HNO3) and nitrous oxide (N2O) zonal means data products from the "Global Ozone Chemistry and Related trace gas Data Records for the Stratosphere (GOZCARDS)" project, part of the NASA Making Earth Science Data Records for Use in Research Environments (MEaSUREs) Program. These products include monthly merged and source data for the above species (with start year being 1979 for O3, and later for other species).

Additionally, data for 2011 and 2012 from the previously released hydrogen chloride (HCl) and “MERRA-based” temperature (T) zonal mean data products are now available.

Other GOZCARDS products are planned for later in 2013. Users should review the README document for additional information. Information on these data, including the README document, and access to the data are available at http://disc.sci.gsfc.nasa.gov/datareleases/measures-gozcards-data-now-available.

See also the JPL website at http://gozcards.jpl.nasa.gov.

Science Update: Validation of global ozone profile measurements

In their JGR article, Koji Imai and numerous SPARC scientists as co-authors, present validation studies of ozone profiles in the middle atmosphere.

The data was taken by Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) onboard the International Space Station ISS from October 2009 to April 2010. Comparisons of the data with satellite observations and chemistry-transport models indicate that the observations agree generally within 10%. The SMILES data also capture diurnal variability well.

Find the full article here.

Science Update: The importance of time-varying forcing for Quasi-Biannial Oscillation modulation of the atmospheric 11-year solar cycle signal

In their JGR article authored by SOLARIS-HEPPA activity leader Katja Matthes and colleagues, the results are presented from multi-decadal sensitivity experiments with time-varying solar cycle and Quasi-Biennial Oscillation (QBO) forcings.

Multi-decadal simulations using the NCAR’s Whole Atmosphere Community Climate Model (WACCM3.1) were carried out to assess the time-varying forcing of solar variability and the QBO. In the tropical upper stratsphere the annual mean solar response is found to be independent of the presence of the QBO. Only the experiment including both solar and QBO forcing agrees reasonably with observations, indicating that both forcings are necessary to realistically simulating the climate. The QBO is also found to modulate the background zonal mean wind climatology, which in turn modifies the modelled solar signal.

Find the full article here.

Science Update: Combined SAGE II-GOMOS ozone profile data set 1984-2011 and trend analysis of the vertical distribution of ozone

A new, homogeneous long-term data set of vertical ozone profile observations has been compiled using SAGE II and GOMOS observations. The combined data set covers latitudes 60°N-60°S and the altitude range of 20-60km (at 1km vertical resolution) for the period 1984-2011. Trend analysis of the data indicates that in equatorial regions at altitudes of 38-45km the negative ozone trend observed from 1984-1997 has reversed to a small positive trend of 0-2% per decade. In the 30-35km range, however, ozone loss has increased. At mid-latitudes a similar trend reversal is observed, with the negative trend prior to 1997 (-4-10%/decade) also becoming a small positive trend (0-2%/decade).

Find the full article here.

Science Update: Volcanic sulfate deposition to Greenland and Antarctica: a modeling sensitivity study

In their JGR publication co-authored by SPARC scientist Claudia Timmreck, SSiRC activity leader, the assumption is tested using the MAECHAM5-HAM global aerosol-climate model that the atmospheric burden and deposition of volcanic sulfate aerosol are directly proportional. The deposition efficiency is found to depend on the magnitude and season of stratospheric sulfur injection. Eruptions with large SO2 injections are associated with increases in aerosol particle size, which influence sedimentation velocity and radiative properties, which in turn lead to dynamic changes including a strengthening of the winter polar vortices. This strengthening inhibits stratospheric aerosol transport to high latitudes and, for very large eruptions, a non-linear relationship of sulfate deposition is observed between Antarctica and Greenland (with sulfate deposition over Antarctica). These results may be of significance when interpreting ice core sulfate measurements.

Find the full article here.

SPARC General Assembly: Abstract submission now open

The 5th SPARC General Assembly will bring together hundreds of experts to discuss and assess the emerging role the stratosphere plays in the climate system, including chemical climate modelling with a focus on tropospheric chemistry will be presented.

This event will take place from 12-17 January 2014 in Queenstown, New Zealand. Abstract submission is now open. Travel support for early career scientists and scientists from emerging and developing countries is available, please see the website for further details on how to apply..

Find a description of sessions; submit your abstract; go to conference website.