A sulfur dioxide Covariance-Based Retrieval Algorithm (COBRA): application to TROPOMI reveals new emission sources Atmospheric Chemistry and Physics DOI 10.5194/acp-21-16727-2021 28 January 2022 We present a new algorithm to retrieve sulfur dioxide from space UV measurements. We apply the technique to high-resolution TROPOMI measurements and demonstrate the high sensitivity of the approach to weak SO2 emissions worldwide with an unprecedented limit of detection of 8 kt yr-1. This result has broad implications for atmospheric science studies dealing with improving emission inventories and identifying and quantifying missing sources, in the context of air quality and climate. COBRA): application to TROPOMI reveals new emission sources">Read more
Feedback mechanisms between precipitation and dissolution reactions across randomly heterogeneous conductivity fields Hydrology and Earth System Sciences DOI 10.5194/hess-25-5905-2021 26 January 2022 The interplay between dissolution, precipitation and transport is widely encountered in porous media, from CO2 storage to cave formation in carbonate rocks. We show that dissolution occurs along preferential flow paths with high hydraulic conductivity, while precipitation occurs at locations close to yet separated from these flow paths, thus further funneling the flow and changing the probability density function of the transport, as measured on the altered conductivity field at various times. Read more
Dynamics of fortnightly water level variations along a tide-dominated estuary with negligible river discharge Ocean Science DOI 10.5194/os-17-1605-2021 24 January 2022 Understanding tidal hydrodynamics is essential for water resources management in estuarine environments. In this study, we propose an analytical model to examine the fortnightly water level variations due to tidal motions alone in tide-dominated estuaries. Details of the analytical model show that changes in the mean depth or length of semi-arid estuaries affect the fortnightly tide amplitude, which has significant potential impacts on the estuarine ecosystem management. Read more
A differential emissivity imaging technique for measuring hydrometeor mass and type Atmospheric Measurement Techniques DOI 10.5194/amt-14-6973-2021 21 January 2022 This paper describes a new instrument for quantifying the physical characteristics of hydrometeors such as snow and rain. The device can measure the mass, size, density and type of individual hydrometeors as well as their bulk properties. The instrument is called the Differential Emissivity Imaging Disdrometer (DEID) and is composed of a thermal camera and hotplate. The DEID measures hydrometeors at sampling frequencies up to 1 Hz with masses and effective diameters greater than 1 µg and 200 µm. Read more
Brief communication: Effective earthquake early warning systems: appropriate messaging and public awareness roles Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-3243-2021 19 January 2022 Earthquake early warning systems (EEWSs) can help reduce losses, but their effectiveness depends on adequate public perception and understanding of EEWSs. This study examined the performance of the EEWS in China’s Sichuan Province during the 2019 Changning earthquake. We found a big gap existed between the EEWS’s message, the public’s perception of it, and their response. The study highlights the importance of gauging EEWS alert effectiveness and public participation for long-term resiliency. Read more
Photosynthetic activity in Devonian Foraminifera Biogeosciences DOI 10.5194/bg-18-5719-2021 17 January 2022 Benthic foraminifera play a significant role in modern reefal ecosystems mainly due to their symbiosis with photosynthetic microorganisms. Foraminifera were also components of Devonian stromatoporoid coral reefs; however, whether they could have harbored symbionts has remained unclear. We show that Devonian foraminifera may have stayed photosynthetically active, which likely had an impact on their evolutionary radiation and possibly also on the functioning of Paleozoic shallow marine ecosystems. Read more
The interpretation of temperature and salinity variables in numerical ocean model output and the calculation of heat fluxes and heat content Geoscientific Model Development DOI 10.5194/gmd-14-6445-2021 14 January 2022 We show that the way that the air–sea heat flux is treated in ocean models means that the model’s temperature variable should be interpreted as being Conservative Temperature, irrespective of whether the equation of state used in an ocean model is EOS-80 or TEOS-10. Read more
A dynamical adjustment perspective on extreme event attribution Weather and Climate Dynamics DOI 10.5194/wcd-2-971-2021 12 January 2022 Attribution of the causes of extreme temperature events has become active research due to the wide-ranging impacts of recent heat waves and cold spells. Here we show that a purely observational approach based on atmospheric circulation analogues and resampling provides a robust quantification of the various dynamic and thermodynamic contributions to specific extreme temperature events. The approach can easily be integrated in the toolbox of any real-time extreme event attribution system. Read more
An Arctic ozone hole in 2020 if not for the Montreal Protocol Atmospheric Chemistry and Physics DOI 10.5194/acp-21-15771-2021 10 January 2022 We use satellite and balloon measurements to evaluate modeled ozone loss seen in the unusually cold Arctic of 2020 in the real world and compare it to simulations of a world avoided. We show that extensive denitrification in 2020 provides an important test case for stratospheric model process representations. If the Montreal Protocol had not banned ozone-depleting substances, an Arctic ozone hole would have emerged for the first time in spring 2020 that is comparable to those in the Antarctic. Read more
Assessing the representation of the Australian carbon cycle in global vegetation models Biogeosciences DOI 10.5194/bg-18-5639-2021 7 January 2022 The Australian continent is included in global assessments of the carbon cycle such as the global carbon budget, yet the performance of dynamic global vegetation models (DGVMs) over Australia has rarely been evaluated. We assessed simulations by an ensemble of dynamic global vegetation models over Australia and highlighted a number of key areas that lead to model divergence on both short (inter-annual) and long (decadal) timescales. Read more
