The anxieties of a science diplomat: field coproduction of climate knowledge and the rise and fall of Hans Ahlmann's polar warming".

In the decades between the world wars there were several attempts to document and explain perceived tendencies of atmospheric warming. Hans Ahlmann, a seminal figure in modern glaciology and a science policy adviser and diplomat, constructed a theory of "polar warming" using field results from glacier melting in the Arctic. This article aims to link the rise and fall of "polar warming" with Ahlmann's style of fieldwork. In Ahlmann's view, fieldwork should (1) enhance credibility of polar climate science by emulating laboratory methods and (2) secure knowledge in remote places through collaboration with local residents and fieldworkers. The bodily nature of this style of knowledge production turned out to be an asset in establishing Ahlmann's theory of polar warming but ultimately proved nonresilient to theories of anthropogenic climate change, which became influential from the 1950s onward.

The environment as seen through the life of a journal: Ambio 1972-2022.

Emerging after World War II "the environment" as a modern concept turned in the years around 1970 into a phase of institutionalization in science, civic society, and politics. Part of this was the foundation of journals. The majority became "environmental specialist journals", typically based in established disciplines. Some became "environmental generalist journals", covering broad knowledge areas and often with an ambition to be policy relevant. A significant and early member of the latter category was Ambio, founded 1972. This article presents an overview of the journal's first 50 years, with a focus on main changes in scientific content, political context, and editorial directions. A key finding is that the journal reflects an increasing pluralization of "the environment" with concepts such as global change, climate change, Earth system science, Anthropocene, resilience, and environmental governance. Another finding is that the journal has also itself influenced developments through publishing work on new concepts and ideas.

Decline and diversity in Swedish seas: Environmental narratives in marine history, science and policy.

Before the mid-twentieth century, there was no comprehensive narrative about empirical conditions in Swedish seas. Around 1970, this view changed profoundly. In line with growing research and the emergence of 'the environment' as a defining concept, conditions in Swedish seas were framed as a 'narrative of decline'. Marine scientists have since recorded more diverse developments than are described by an overall declensionist narrative. Data show trends of interrupted decline, variability and even recovery, taking place at least partly in response to effective policy and legislation. We suggest that beyond the specialised fields of marine sciences and marine environmental history, the overarching narrative of decline has persisted, paying little attention to local and regional particularities as well as cultural and political dimensions of the marine environment. This overly uniform narrative risks obscuring historical reality and, hence, fails to adequately inform policy and the public about developments and outcomes of interventions in Swedish seas.

Sustainability. Planetary boundaries: guiding human development on a changing planet.

The planetary boundaries framework defines a safe operating space for humanity based on the intrinsic biophysical processes that regulate the stability of the Earth system. Here, we revise and update the planetary boundary framework, with a focus on the underpinning biophysical science, based on targeted input from expert research communities and on more general scientific advances over the past 5 years. Several of the boundaries now have a two-tier approach, reflecting the importance of cross-scale interactions and the regional-level heterogeneity of the processes that underpin the boundaries. Two core boundaries­climate change and biosphere integrity­have been identified, each of which has the potential on its own to drive the Earth system into a new state should they be substantially and persistently transgressed.