English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Downward transport of ozone (O3) from thestratosphere can be a significant contributor to tropospheric O3background levels. However, this process often is not well represented incurrent regional models. In this study, we develop a seasonally andspatially varying potential vorticity (PV)-based function to parameterizeupper tropospheric and/or lower stratospheric (UTLS) O3 in a chemistrytransport model. This dynamic O3–PV function is developed based on21-year ozonesonde records from World Ozone and Ultraviolet Radiation DataCentre (WOUDC) with corresponding PV values from a 21-year Weather Researchand Forecasting (WRF) simulation across the Northern Hemisphere from 1990 to2010. The result suggests strong spatial and seasonal variations ofO3 ∕ PV ratios which exhibits large values in the upper layers and inhigh-latitude regions, with highest values in spring and the lowest valuesin autumn over an annual cycle. The newly developed O3 ∕ PV function wasthen applied in the Community Multiscale Air Quality (CMAQ) model for anannual simulation of the year 2006. The simulated UTLS O3 agrees muchbetter with observations in both magnitude and seasonality after theimplementation of the new parameterization. Considerable impacts on surfaceO3 model performance were found in the comparison with observationsfrom three observational networks, i.e., EMEP, CASTNET and WDCGG. With thenew parameterization, the negative bias in spring is reduced from −20 to−15 % in the reference case to −9 to −1 %, while the positive bias inautumn is increased from 1 to 15 % in the reference case to 5 to 22 %.Therefore, the downward transport of O3 from upper layers has largeimpacts on surface concentration and needs to be properly represented inregional models

atmospheric chemistry and physics

Representing the effects of stratosphere–troposphere exchange on 3-D O&amp;lt;sub&amp;gt;3&amp;lt;/sub&amp;gt; distributions in chemistry transport models using a potential vorticity-based parameterization