Science Update: 22-28 November

A selection of new science articles from the past week of interest to the SPARC community(a SPARC Office choice).

The impact of temperature resolution on trajectory modelling of stratospheric water vapour. By T. Wang et al. in Atmospheric Chemistry and Physics Discussions.

Global emissions of refrigerants HCFC-22 and HFC-134a: Unforeseen seasonal contributions. By B. Xiang et al. in Proceedings of the National Academy of Sciences of the United States of America.

Direct and ozone-mediated forcing of the Southern Annular Mode by greenhouse gases. By O. Morgenstern et al. in Geophysical Research Letters.

Global Hawk dropsonde observations of the Arctic atmosphere obtained during the Winter Storms and Pacific Atmospheric Rivers (WISPAR) field campaign. By J.M. Intrieri et al. in Atmospheric Measurement Techniques.

Global Atmospheric Sulfur Budget under Volcanically Quiescent Conditions: Aerosol-Chemistry-Climate Model Predictions and Validation. By J.-X. Sheng et al. in the Journal of Geophysical research: Atmospheres.

The POLARCAT Model Intercomparison Project (POLMIP): overview and evaluation with observations. By L.K. Emmons et al. in Atmospheric Chemistry and Physics Discussions.

Characteristics of tropopause parameters as observed with GPS radio occultation. By T. Rieckh et al. in Atmospheric Measurement Techniques.

Assimilation of GNSS radio occultation observations in GRAPES. By Y. Liu and J. Xue in Atmospheric Measurement Techniques.

Inorganic chlorine variability in the Antarctic vortex and implications for ozone recovery. By S.E. Strahan et al. in the Journal of Geophysical research: Atmospheres.

Validation of MIPAS IMK/IAA V5R_O3_224 ozone profiles. By A. Laeng et al. in Atmospheric Measurement Techniques.

Science Update: 15-21 November

A selection of new science articles from the past week of interest to the SPARC community (a SPARC Office choice).

Transition from geostrophic turbulence to inertia–gravity waves in the atmospheric energy spectrum. By J. Callies et al. in the Proceedings of the National Academy of Sciences of the United States of America.

Modeling the climate impact of Southern Hemisphere ozone depletion: The importance of the ozone dataset. By P.J. Young et al. in Geophysical Research Letters.

Hemispheric distributions and inter-annual variability of NOy produced by Energetic Particle Precipitation in 2002–2012. By B. Funke et al. in the Journal of Geophysical Research: Atmospheres.

Quantifying the value of redundant measurements at GCOS Reference Upper-Air Network sites. By F. Madonna et al. in Atmospheric Measurement Techniques.

Characteristics and sources of gravity waves observed in noctilucent cloud over Norway. By T.D. Demissie et al. in Atmospheric Chemistry and Physics.

Antarctic ocean and sea ice response to ozone depletion: a two timescale problem. By D. Ferreira et al. in the Journal of Climate.

Cirrus and water vapour transport in the tropical tropopause layer – Part 2: Roles of ice nucleation and sedimentation, cloud dynamics, and moisture conditions. By T. Dinh et al. in Atmospheric Chemistry and Physics.

Is the residual vertical velocity a good proxy for stratosphere-troposphere exchange of ozone? By J. Hsu and M.J. Prather in Geophysical Research Letters.

AGU Chapman Conference on "The Width of the Tropics: Climate Variations and Their Impacts"

26-31 July 2015, Santa Fe, New Mexico, USA

This multidisciplinary conference will explore the state of the science and identify future research directions relevant to the issue of tropical belt widening.

A particular emphasis will be cross-fertilization among the wide range of climate scientists contributing to our understanding of the problem.

Four main themes are planned:
1. What determines the width of the tropical belt?
2. How and why has the tropical width changed in the past?
3. How and why might the tropical width change in the future?
4. What are the impacts for the oceans, cryosphere, hydrologic cycle, human society, and ecosystems?

Conference details are at chapman.agu.org/tropics/

QBO Modelling and Reanalyses Workshop

Deadline for abstracts: 12 Dec 2014

16-18 March 2015, Victoria BC, Canada

The objective of the QBO Modelling and Reanalyses Workshop is to better understand the QBO in observations and reanalyses and to improve the fidelity of tropical stratosphere variability in present-day GCMs. The Workshop will (1) evaluate present-day QBO variability in observations and models, and (2) design joint numerical experiments following an active discussion of modelling groups.

The meeting will be tightly focussed, with invited and contributed science presentations and planned experiment discussions. Please register your interest for the Workshop online by following the link below, although numbers are limited. There is no Workshop fee.

The Workshop is an outflow of the QBOi activity and the QBO and Tropical Variability chapter of the SPARC S-RIP Report. The Workshop is kindly sponsored by the UK National Environmental Research Council and SPARC.

To find out more, please visit the Workshop homepage.

Science Update: 8-14 November

A selection of new science articles of interest to the SPARC community from the past week (A SPARC Office choice).

Thunderstorms enhance tropospheric ozone by wrapping and shedding stratospheric air. By L.L. Pan et al. in Geophysical Research Letters.

Total volcanic stratospheric aerosol optical depths and implications for global climate change. By D.A. Ridley et al. in Geophysical Research Letters.

Airborne verification of CALIPSO products over the Amazon: a case study of daytime observations in a complex atmospheric scene. By F. Marenco et al. in Atmospheric Chemistry and Physics.

Biogenic SOA formation through gas-phase oxidation and gas-to-particle partitioning – a comparison between process models of varying complexity. By E. Hermansson et al. in Atmospheric Chemistry and Physics.

Application of GPS radio occultation to the assessment of temperature profile retrievals from microwave and infrared sounders. By M. Feltz et al. in Atmospheric Measurement Techniques.

Recalibration and Merging of SSU Observations for Stratospheric Temperature Trend Studies. By C.-Z. Zou et al. in the Journal of Geophysical Research: Atmospheres.

Improving stratospheric transport trend analysis based on SF6 and CO2 measurements. By. E.A. Ray et al. in the Journal of Geophysical Research: Atmospheres.

Variability of Antarctic ozone loss in the last decade (2004–2013): high resolution simulations compared to Aura MLS observations. By J. Kuttippurath et al. in Atmospheric Chemistry and Physics Discussions.

Satellite observations of stratospheric carbonyl fluoride. By J.J. Harrison et al. in Atmospheric Chemistry and Physics.

Science Update: 1-7 November

A selection of new science articles of interest to the SPARC community from the past week (A SPARC Office choice).

Total volcanic stratospheric aerosol optical depths and implications for global climate change. By D.A. Ridley et al. in Geophysical Research Letters.

Denitrification by large NAT particles: the impact of reduced settling velocities and hints on particle characteristics. By W. Woiwode et al. in Atmospheric Chemistry and Physics.

Variations of stratospheric water vapor over the past three decades. By A.E. Dessler et al. in the Journal of Geophysical Research: Atmospheres.

Recent Northern Hemisphere stratospheric HCl increase due to atmospheric circulation changes. By E. Mahieu et al. in Nature.

Lidar-observed enhancement of aerosols in the upper troposphere and lower stratosphere over the Tibetan Plateau induced by the Nabro volcano eruption. By Q.S. He et al. in Atmospheric Chemistry and Physics.

MIPAS temperature from the stratosphere to the lower thermosphere: Comparison of vM21 with ACE-FTS, MLS, OSIRIS, SABER, SOFIE and lidar measurements. By M. García-Comas et al. in Atmospheric Measurement Techniques.