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Mechanisms behind the phenomenon of Arctic amplification are widely discussed. To contribute to this debate, the (AC)3 project was established in 2016 (www.ac3-tr.de/). It comprises modeling and data analysis efforts as well as observational elements. The project has assembled a wealth of ground-based, airborne, shipborne, and satellite data of physical, chemical, and meteorological properties of the Arctic atmosphere, cryosphere, and upper ocean that are available for the Arctic climate research community. Short-term changes and indications of long-term trends in Arctic climate parameters have been detected using existing and new data. For example, a distinct atmospheric moistening, an increase of regional storm activities, an amplified winter warming in the Svalbard and North Pole regions, and a decrease of sea ice thickness in the Fram Strait and of snow depth on sea ice have been identified. A positive trend of tropospheric bromine monoxide (BrO) column densities during polar spring was verified. Local marine/biogenic sources for cloud condensation nuclei and ice nucleating particles were found. Atmospheric–ocean and radiative transfer models were advanced by applying new parameterizations of surface albedo, cloud droplet activation, convective plumes and related processes over leads, and turbulent transfer coefficients for stable surface layers. Four modes of the surface radiative energy budget were explored and reproduced by simulations. To advance the future synthesis of the results, cross-cutting activities are being developed aiming to answer key questions in four focus areas: lapse rate feedback, surface processes, Arctic mixed-phase clouds, and airmass transport and transformation.

Polar lows (PLs) are small, intense cyclones that form at high latitudes during the winter. Their high wind speeds and heavy precipitation can have substantial impacts on shipping, coastal communities and infrastructure. However, low-resolution climate models poorly simulate PLs, which reduces the confidence in their future projections. In this study, Northern Hemisphere (NH) PLs are assessed for the first time in a high-resolution (25 km) global climate model, N512 HadGEM3-GA3, for both present-day and future RCP8.5 climate scenarios. The representation of PLs is found to agree reasonably well with the NCEP-CFS reanalysis. The number of NH PLs are projected to substantially decrease (by over 60%) by the end of the 21st century, which is largely due to an increase in atmospheric static stability. Large decreases in PL activity are found in the Norwegian Sea, north-east Atlantic and north-west Pacific Oceans. Smaller changes are found in regions of current PL activity, such as the Barents and Labrador Seas, while new regions of PL activity along the northern Russian coastline are found where the Arctic sea ice is projected to disappear. The spatial differences found in future PL activity could thus have a substantial impact on forthcoming activities in the Arctic region.

Polar lows (PLs) are intense mesoscale cyclones that form at high latitudes during winter. Their high wind speeds and heavy precipitation can substantially impact offshore infrastructures and coastal communities over regions such as Scandinavia, Russia and Japan. However, large uncertainties regarding their climatology, interaction with the ocean and response to climate change still remain. Using an automatic tracking method and specific identification criteria, a reliable long-term climatology of PLs and their environment is derived from two atmospheric reanalyses. The mean number of PLs differs significantly between reanalyses, however the inter-annual variability of PL numbers is highly correlated between both datasets. PLs activity from these reanalyses is found consistent with observations and literature. The large-scale environment of PLs is found to play a role in the inter-annual variability of PL numbers. The possible impact of PLs on the ocean circulation over the Nordic Seas is investigated using high resolution simulations from a coupled global climate model. As seen in previous studies based on an ocean model with parametrized PLs, this thesis shows, in high resolution climate model simulations, a clear positive link between the ocean surface heat fluxes and PL occurrences. However, in this study, no evidence is found that PLs influence on the ocean density is sufficient to destabilize the water column and trigger deep ocean convection over the Nordic Seas. Finally, for the first time, the representation of PLs and their environment are assessed in a high resolution atmosphere-only global climate model, for both present climate conditions and a future climate scenario. Furthermore, the impact of the resolution of the model on the representation of PLs is assessed using simulations from three different horizontal resolutions for both climate conditions. Overall the PL numbers are expected to decrease in the future, mainly due to an increase in static stability. However, regional differences appear and new areas for PL occurrence emerge over the Arctic Ocean. The horizontal resolution of the climate model is found to affect the mean numbers of PLs but not their activity.

SEA-EU-NET project is based on the program Capacities under the 7th Framework Program (FP7) of the EU Commission with the strategic objective of Integrating and Strengthening the EU-ASEAN Science and Technology Dialogue through coordination and supporting activities. It is a 4 years program started in January 2008, and is currently supported by 22 institutions from Europe and South-East Asia. The objective is to increase the quality, quantity, profile and impact of bi-regional Science and Technology cooperation between the 10 ASEAN countries and the Members and Associated States of the European Union. Every Thematic Priority of FP7 has to implement dedicated international cooperation activities to achieve the program's goals and to address specific problems of ‘Third Countries/Regions’ (non-EU Members States or non-Associated States). This activity is performed through the organization of annual Thematic Workshops, with the objective to produce a document containing duly justified proposals for Specific International Cooperation Actions. This paper presents the results of the Thematic Workshop on ‘Food Quality, Safety and Traceability’. This expert meeting was done in Thailand in February 2009. Titles for 10 possible themes were identified on the following fields: Bacteria antibioresistance, Mycotoxins, Pathogens (bacteria), Pesticides, Heavy metals, Food traceability, Food Supply Chain, Preserving nutrients, Consumers attitudes, Peri-urban markets.