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Atmospheric Chemistry and Physics

Technical note: LIMS observations of lower stratospheric ozone in the southern polar springtime of 1978

The Nimbus 7 limb infrared monitor of the stratosphere (LIMS) instrument operated from October 25, 1978, through May 28, 1979. This note focuses on the lower stratosphere of the southern hemisphere, subpolar regions in relation to the position of the polar vortex. Both LIMS ozone and nitric acid show reductions within the edge of the polar vortex at 46 hPa near 60° S from late October through mid-November 1978, indicating that there was a chemical loss of Antarctic ozone some weeks earlier.

Climate of the Past

Terrestrial methane emissions from the Last Glacial Maximum to the preindustrial period

We investigate the changes in natural methane emissions between the Last Glacial Maximum and preindustrial periods with a methane-enabled version of MPI-ESM. We consider all natural sources of methane except for emissions from wild animals and geological sources. Changes are dominated by changes in tropical wetland emissions, high-latitude wetlands play a secondary role, and all other natural sources are of minor importance. We explain the changes in ice core methane by methane emissions only.

Atmospheric Chemistry and Physics

Methane emissions from the Munich Oktoberfest

We demonstrate for the first time that large festivals can be significant methane sources, though they are not included in emission inventories. We combined in situ measurements with a Gaussian plume model to determine the Oktoberfest emissions and show that they are not due solely to human biogenic emissions, but are instead primarily fossil fuel related. Our study provides the foundation to develop reduction policies for such events and new pathways to mitigate fossil fuel methane emissions.

Atmospheric Chemistry and Physics

Deconvolution of boundary layer depth and aerosol constraints on cloud water path in subtropical stratocumulus decks

Cloud water content and the number of droplets inside clouds covary with boundary layer depth. This covariation may amplify the change in water content due to a change in droplet number inferred from long-term observations. Taking this into account shows that the change in water content for increased droplet number in observations and high-resolution simulations agrees in shallow boundary layers. Meanwhile, deep boundary layers are under-sampled in process-scale simulations and observations.

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Seismology in the Time of COVID-19

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The COVID-19 pandemic has brought us somewhere new. With many of us confined to our homes, the Seismology ECS representatives launch a new blog series, where they put together articles, reflections, and stories to accompany the community through this unprecedented historic period. Read the articles here: Creating Value for Safety: from earthquake preparedness to pandemic outbreak response __________________________________________________ For defeating the COVID-19, follow your local public health department’s guidelines. Stay home and slow the transmission of the virus.

Imaggeo on Mondays: Red triassic sandstone

Imaggeo on Mondays: Red triassic sandstone

As child growing up on the south coast of Devon in the UK, I never really realised that our beaches were unusual. A glorious, glowing orange-red colour, the cliffs that you can see in this photograph by Sarah Weick produced similarly red sand beaches and warm ochre soils. The bright colour is the result of the sandstone and conglomerates of these rocks, collectively called the New Red Sandstones, being deposited during a time in the Triassic period, when this part …