ALBERT

Description: The health of the ocean, central to human well-being, has now reached a critical point. Most fish stocks are overexploited, climate change and increased dissolved carbon dioxide are changing ocean chemistry and disrupting species throughout food webs, and the fundamental capacity of the ocean to regulate the climate has been altered. However, key technical, organizational, and conceptual scientific barriers have prevented the identification of policy levers for sustainability and transformative action. Here, we recommend key strategies to address these challenges, including (1) stronger integration of sciences and (2) ocean-observing systems, (3) improved science-policy interfaces, (4) new partnerships supported by (5) a new ocean-climate finance system, and (6) improved ocean literacy and education to modify social norms and behaviors. Adopting these strategies could help establish ocean science as a key foundation of broader sustainability transformations.

Description: The genus Kogia, which comprises only two extant species, Kogia sima and Kogia breviceps, represents one of the least known groups of cetaceans in the global ocean. In some coastal regions, however, stranding events of these species have been relatively common over the last decades. Stranding provides the opportunity to investigate the biology of these cetaceans and to explore the epidemiological aspects associated with the mortality of the organisms found on the beach. A number of disturbances (including pelagic fisheries, chemical pollution, boat strikes, and noise pollution) have been confirmed to pose a particular threat to the Kogia species. However, no study has yet investigated potential relationships between environmental conditions and stranding events. Here we analyse how a collection of environmental, physical, and biological variables, such as wind, sea surface temperature (SST), water depth, and chlorophyll-a, correlate to Kogia stranding events along the Brazilian coast. The results of our statistical analyses suggest that K. sima is more likely found in warm tropical waters, which provide an explanation for the high frequency of stranding in northeastern Brazilian coast. In contrast, K. breviceps appears to have a preference for temperate and productive waters. Wind speed results to be also an important factor for predicting Kogia strandings in Brazilian coast. Additionally, literature information in combination with our own data and analyses of stomach contents confirms that oceanic cephalopods constitute the primary nutritional source of both Kogia species. By using the available information as a qualitative proxy for habitat preference and feeding ecology, our study provides a novel and comprehensive assessment of Kogia stranding data in relation to environmental conditions along the Brazilian coast.

Description: Geomagnetically Induced currents (GICs) arise from rapid geomagnetic field variations caused by highly energized solar wind. These currents flow in the Earth's surface and along conductive man-made infrastructures galvanically connected to Earth, as power systems. Consequently, electric power stability can be compromised and, in extreme cases, can lead to blackouts.Accurate GIC simulations require knowledge of the geomagnetic field variations, the Earth's conductivity, and power grid parameters. To accurately estimate the magnitude of GICs, we need to understand how the conductivity model is affected by geological structures. Testing various conductivity models (e.g., tighter magnetotelluric sounding grid and presence/absence of specific geological structures) can determine the sensitivity of our GIC calculations to different geological structures. This information is vital in accessing the realistic hazard to specific substations of power grids.Additionally, GIC measurements can be used to improve the conductivity model. Since August 30th 2021, we have been monitoring GIC currents flowing through a transformer's neutral at Paraimo (SPI) substation. Comparing with simulations, we noticed a deterioration of correlation at lower frequencies, indicating imprecision of our conductivity model for deeper layers. Given the availability of geomagnetic (at the nearby observatory of Coimbra) and GIC measurements, we can carry on different tests and estimate a local surface impedance. Then, we can invert it to try to extract the 1D ground conductivity structure at depth, using standard MT tools [1,2].[1] 10.1109/UPEC50034.2021.9548157[2] https://doi.org/10.1186/BF03352040