The central objective of the Hydromorphology IV Workshop was to exchange experiences and information and to identify and reflect on challenges of the administrative and practical implementation processes of watercourse development measures.

This study, co-authored by Raffaele Piria, analyzes energy industry and policy developments on hydrogen in the U.S. and develops an agenda for cooperation between Germany and the U.S. in this area. In addition to the foreign policy discourse, there are many opportunities for cooperation between Germany and the U.S. in the field of hydrogen.

Plastics are all around us and make up an essential part of our daily lives. How much do we know about this material, its variety, the associated environmental problems and possible solutions? The quiz "Plastics in the environment - What do you know?" invites you to test your knowledge around the topic of plastics in five categories. Furthermore, the category "Questions for adults & children" contains questions suited for children.

The policy brief discusses the different policy pathways to reach the climate target, as presented in the EU Commissions Impact Assessement of the 2030 target plan. There are different ways how the EU can reduce emissions to -55%: mainly through tighter regulation and standards, primarily via carbon price or trough a mix of both. The policy mix route may seem most attractive: politically, it is the path of least resistance, as it continues on the current trajectory. And it promises the best of both worlds – the efficiency of carbon pricing and the certainty of regulatory approaches. At the same time, the mix has some conceptual arguments in favor: companion policies, like standards and infrastructure investment, ensure that consumers have more climate-friendly options to choose from and bring down their cost. Thereby, they make it easier to stomach higher carbon prices.

Doris Knoblauch gave a presentation on plastic waste at the Freudberg School in Berlin on 9 December 2020. The lecture took place as part of the "Plastic Pirates" project.

In the wake of Joe Biden's election as 46th President of the United States, Dr. Camilla Bausch contributed a blog post for the Global Public Policy Institute's Peace Lab on how multilateralism could help address the climate crisis. This is a timely contribution as it is complimentary to the current work on the German government's new White Paper on multilateralism. In her blog post, Dr. Bausch addresses a broad range of climate diplomacy topics, taking into account the role of Germany as well as the European Green Deal, the Paris Climate Agreement, the UN Agenda 2030, the dynamics within the G20 and the role of science.

This article by Doris Knoblauch and Hannes Schritt (both Ecologic Institute) is part of the anthology "Einfach weglassen? Ein wissenschaftliches Lesebuch zur Reduktion von Plastikverpackungen im Lebensmittelhandel" (Simply Omit? A Scientific Reader on the Reduction of Plastic Packaging in the Food Trade). It deals with the emergence of plastic packaging in Germany and its known environmental impacts. The authors demonstrate that there is a close correlation between the amount of plastic packaging produced and the gross domestic product (GDP) - which, interestingly, is stronger than the correlation between GDP and packaging overall. In this context, avoidance strategies and improvement options for the circular economy are discussed.

The discussion about plastic waste is anything but new for German municipalities. In fact, as early as the 1980s, numerous German municipalities were experimenting with plastic waste prevention regulations and waste prevention in general. A further impetus for plastic waste prevention was provided in the early 1990s with the discussions on the introduction of a nationwide packaging ordinance. After almost three decades of stagnation – including setbacks with regard to the expansion of return systems and the increase of single-use packaging – the issue of plastic prevention and packaging reduction in municipalities is now receiving renewed attention as a result of increased societal awareness and political regulations at EU level.

The restrictions associated with the Corona pandemic have suddenly changed the behavior of traffic participants. As a result, significant numbers of people have taken to cycling and walking. Public transport, on the other hand, is in crisis. The need for social distance and hygiene makes collective means of transportation unappealing, and the demand for car-sharing services has dropped significantly. At the same time, the private car is experiencing a renaissance.

The EU is discussing whether its 2030 climate target should be a net target or gross target. Net targets treat CO2 removal and greenhouse gas emission reductions the same, although they are fundamentally different. To avoid a major step backwards, the EU should formulate separate targets for emissions reductions and CO2 removal, argues Nils Meyer-Ohlendorf in his contribution to the Tagesspiegel.

As part of the Berlin Re-Use Initiative, the online expert dialog on the recycling of gypsum took place on 26 November 2020. This expert dialogue, to which the Senate Department for the Environment, Transport and Climate Protection of the State of Berlin invited together with relevant associations and companies, was dedicated to important issues around gypsum recycling. Eighty-five people took part in the expert dialog.

This user manual supports the members of the German Roundtable on Marine Litter in using the internet platform https://muell-im-meer.de. In the internal area of the platform, members have various possibilities to present their organization and its activities for reducing marine litter as well as to participate in working groups. Distribution list maintenance and communication within the Roundtable on Marine Litter is also handled and documented via the platform.

Climate change is already causing an increase in extreme weather events, including an increase in the frequency and duration of periods of dry and drought conditions. In this paper, colleagues of the Emschergenossenschaft and Ecologic Institute summarize discussions on coordination and cooperation approaches for low water management and prevention at a workshop in the Emscher region.

Berlin is increasingly developing as a dynamic innovation field of the circular economy – a circular, resource-saving economy. (Social) innovations are no longer generated only in the field of waste recycling, but increasingly in the design and manufacture of sustainable products or with new business models. The event provided insights into current research on the development of the circular economy and the commitment of Berlin's innovators in this field.