Modeling the Sources and Chemistry of Polar Tropospheric Halogens (Cl, Br, and I) Using the CAM-Chem Global Chemistry-Climate Model

31 pags., 12 figs., 6 tabs. -- Open Access funded by Creative Commons Atribution Licence 4.0. -- jame20925-sup-0001_Supporting_Information.pdfCurrent chemistry climate models do not include polar emissions and chemistry of halogens. This work presents the first implementation of an interactive polar module into the very short-lived (VSL) halogen version of the Community Atmosphere Model with Chemistry (CAM-Chem) model. The polar module includes photochemical release of molecular bromine, chlorine, and interhalogens from the sea-ice surface, and brine diffusion of iodine biologically produced underneath and within porous sea-ice. It also includes heterogeneous recycling of inorganic halogen reservoirs deposited over fresh sea-ice surfaces and snow-covered regions. The polar emission of chlorine, bromine, and iodine reach approximately 32, 250, and 39 Gg/year for Antarctica and 33, 271, and 4 Gg/year for the Arctic, respectively, with a marked seasonal cycle mainly driven by sunlight and sea-ice coverage. Model results are validated against polar boundary layer measurements of ClO, BrO, and IO, and satellite BrO and IO columns. This validation includes satellite observations of IO over inner Antarctica for which an iodine “leapfrog” mechanism is proposed to transport active iodine from coastal source regions to the interior of the continent. The modeled chlorine and bromine polar sources represent up to 45% and 80% of the global biogenic VSL and VSL emissions, respectively, while the Antarctic sea-ice iodine flux is ~10 times larger than that from the Southern Ocean. We present the first estimate of the contribution of polar halogen emissions to the global tropospheric halogen budget. CAM-Chem includes now a complete representation of halogen sources and chemistry from pole-to-pole and from the Earth's surface up to the stratopause.This study has been funded by the European Research Council Executive Agency under the European Union′s Horizon 2020 Research and Innovation program (Project “ERC‐2016‐COG 726349 CLIMAHAL”) and supported by the Consejo Superior de Investigaciones Científicas (CSIC) of Spain. Computing resources, support, and data storage are provided and maintained by the Computational and Information System Laboratory from the National Center of Atmospheric Research (CISL,2017). R. P. F. would like to thank CONICET, ANPCyT (PICT 2015‐0714), UNCuyo (SeCTyP M032/3853), and UTN (PID 4920‐194/2018) for the financial support. Partial funding for this work was provided by the Korea Polar Research Institute (KOPRI) project (PE18200). The contributions of the University of Bremen have been supported by the State of Bremen, the German Research Foundation (DFG), the German Aerospace (DLR), and the European Space Agency (ESA). We gratefully acknowledge the funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) —Projektnummer 268020496—TRR 172, within the Transregional Collaborative Research Center “ArctiC Amplification: Climate Relevant Atmospheric and SurfaCe Processes,and Feedback Mechanisms (AC)3 ” in subproject C03 as well as the support by the University of Bremen Institutional Strategy Measure M8 in the framework of the DFG Excellence Initiative

A Platform for Swimming Pool Detection and Legal Verification Using a Multi-Agent System and Remote Image Sensing

Spain is the second country in Europe with the most swimming pools. However, the legal literature estimates that 20% of swimming pools are not declared or irregular.The administration has a corps of people who manually analyze satellite or drone images to detect illegal or irregular structures. This method is costly in terms of effort and time, and it is also a method based on the subjectivity of the person carrying it out. This proposal aims to design a platform that allows the automatic detection of irregular pools. Using geographic information tools (GIS) based on orthophotography, combined with advanced machine learning techniques for object detection, allows this work. Furthermore, using a multi-agent architecture allows the system to be modular, with the possibility of the different parts of the system working together, balancing the workload. The proposed system has been validated by testing it in different towns in Spain. The system has shown promisin results in performing this task, with an F1-Score of 97.1%

Sources and chemistry of polar tropospheric halogens (Cl, Br, I) using the CAM-Chem Global Chemistry-Climate Model, links to netCDF files

Here, we present the first implementation of an interactive polar module into the halogen version of the CAM-Chem model with the intention of expanding the model applicability to the polar regions, besides its widely usage for atmospheric studies throughout the tropics and mid-latitudes. The state-of-the-art polar module considers full gas-phase and heterogeneous inorganic chlorine, bromine and iodine chemistry and sources, which adds up to the organic halogen emissions from the ocean surface (the so-called very short-lived (VSL) substances). The online sea-ice halogen sources depend on the seasonal variation of different types of icy surfaces and the intensity of radiation reaching the polar surface. Our results indicate that the contribution of polar halogen sources represents between 45 and 80% of the global biogenic VSL bromine and chlorine emissions, respectively; and that the Antarctic iodine sea-ice annual flux is ~10 times larger than the total iodine source arising from the Southern Ocean. This work provides, for the first time, quantitative estimates of the annual and seasonal flux strength of each halogen family from the Arctic and Antarctic, as well as their contribution to the global tropospheric halogen budget, highlighting the importance of including the contribution of polar tropospheric halogens in global chemistry-climate models