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Manney, G.

Publications and source records attributed to Manney, G..

At least 19 records

Comparison of measurements and models in stratospheric polar vortex studies

An overview will be given of recent studies comparing model results with observations of stratospheric meteorological and trace gas fields, focusing on the polar vortex during winter. Studies comparing process-oriented (e.g., stability) model, mechanistic (i.e., forced lower boundary near the tropopause) model and general circulation model (GCM) simulations of the dynamics of the polar winter stratosphere with analyzed or assimilated meteorological datasets are reviewed.

modeling↗

Variability of ozone loss during Arctic winter (1991 to 2000) estimated from UARS Microwave Limb Sounder measurement

A comprehensive analysis of version 5 Upper Atmosphere Research Satellite (UARS) Microwave Limb Sounder (MLS) ozone data using a Lagrangian Transport (LT) model provides estimates of chemical ozone depletion for the 1991-1992 through 1997-1998 Arctic winters. These new estimates give a consistent, three-dimensional picture of ozone loss during seven Arctic winters; previous Arctic ozone loss estimates from MLS were based on various earlier data versions and were done only for late winter and only for a subset of the years observed by MLS. We find large interannual variability in the amount, timing, and patterns of ozone depletion and in the degree to which chemical loss is masked by dynamical processes.

Arctic ozone loss↗

Dynamical and chemical contributions to variability in microwave limb sounder Arctic stratoshperic column ozone

Analyses of column ozone above 100 hPa (Col100) derived from Upper Atmosphere Research Satellite Microwave Limb Sounder (MLS) data in February/March 1992-1998 show that about half of the interannual variability in Col100 in the Arctic polar vortex in late winter results from interannual variability in chemical loss. A majority of the remainder results from interannual variability in day-to-day dynamical motions including adiabatic warming/cooling and poleward advection of underlying upper tropospheric subtropical air on short timescales, rather than from variations in descent rates and large-scale transport over the winters. The morphology of Col100 from MLS remains very similar to that in the dynamical models even in the years with most chemical ozone loss. The amount and character of day-to-day variability in dynamical models closely follows that in MLS Col100. Although the morphology of and day-to-day variability in Arctic column ozone are controlled by dynamical processes, chemical ozone loss was a major factor in producing both the low values of and the large interannual variability in Arctic column ozone observed during the 1990s.

Arctic ozone loss↗

Lamination and polar vortex development in fall from ATMOS long-lived trace gases observed during November 1994

Long-lived trace-gas profiles observed by the Atmospheric Trace Molecule Spectroscopy (ATMOS) instrument around the developing polar vortex (the protovortex) during early November 1994 show distinctive inversions (lamiane). High-resolution profiles calculated using a reverse trajectory (RT) model to produce the majority of these laminae, demonstrating that most of these features arise from advection by the large-scale winds.

polar↗

Polar Vortex Conditions During the 1995-96 Artic Winter: Meteorology and MLS Ozone

The 1995-96 northern hemisphere (NH) winter was colder than any of the previous 17 NH winters, with temperatures continuously below the type 1 polar stratospheric cloud (PSC) threshold for over 2 1/2 months; upper tropospheric ridges in late Feb and early Mar 1996 led to the lowest observed NH winter lower stratospheric temperatures, and the latest observation of HN temperatures below the type 2 PSC threshold.

arctic↗