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 Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

. The atmospheric response to the 11-year solar cycle is separated into thecontributions from changes in direct radiative heating and photolysis ratesusing specially designed sensitivity simulations with the UM-UKCA (UnifiedModel coupled to the United Kingdom Chemistry andAerosol model) chemistry–climate model. We perform a number of idealised time-sliceexperiments under perpetual solar maximum (SMAX) and minimum conditions(SMIN), and we find that contributions from changes in direct heating andphotolysis rates are both important for determining the stratosphericshortwave heating, temperature and ozone responses to the amplitude of the11-year solar cycle. The combined effects of the processes are found to belargely additive in the tropics but nonadditive in the Southern Hemisphere(SH) high latitudes during the dynamically active season. Our resultsindicate that, in contrast to the original mechanism proposed in theliterature, the solar-induced changes in the horizontal shortwave heatingrate gradients not only in autumn/early winter but throughout thedynamically active season are important for modulating the dynamicalresponse to changes in solar forcing. In spring, these gradients arestrongly influenced by the shortwave heating anomalies at higher southernlatitudes, which are closely linked to the concurrent changes in ozone. Inaddition, our simulations indicate differences in the winter SH dynamicalresponses between the experiments. We suggest a couple of potential driversof the simulated differences, i.e. the role of enhanced zonally asymmetricozone heating brought about by the increased solar-induced ozone levelsunder SMAX and/or sensitivity of the polar dynamical response to thealtitude of the anomalous radiative tendencies. All in all, our resultssuggest that solar-induced changes in ozone, both in thetropics/mid-latitudes and the polar regions, are important for modulatingthe SH dynamical response to the 11-year solar cycle. In addition, themarkedly nonadditive character of the SH polar vortex response simulated inaustral spring highlights the need for consistent model implementation ofthe solar cycle forcing in both the radiative heating and photolysisschemes.

atmospheric chemistry and physics

Separating the role of direct radiative heating and photolysis in modulating the atmospheric response to the amplitude of the 11-year solar cycle forcing