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Satellite services are fundamental to the global economy, and their design reflects a tradeoff between coverage and cost. Here, we report the discovery of two alternative 4-satellite constellations with 24- and 48-hour periods, both of which attain nearly continuous global coverage. The 4-satellite constellations harness energy from nonlinear orbital perturbation forces (e.g., Earth's geopotential, gravitational effects of the sun and moon, and solar radiation pressure) to reduce their propellant and maintenance costs. Our findings demonstrate that small sacrifices in global coverage at user-specified longitudes allow operationally viable constellations with significantly reduced mass-to-orbit costs and increased design life. The 24-hour period constellation reduces the overall required vehicle mass budget for propellant by approximately 60% compared to a geostationary Earth orbit constellation with similar coverage over typical satellite lifetimes. Mass savings of this magnitude permit the use of less expensive launch vehicles, installation of additional instruments, and substantially improved mission life.

Climate impacts increasingly unfold in interlinked systems of people, nature, and infrastructure. The cascading consequences are revealing sometimes surprising connections across sectors and regions, and prospects for climate responses also depend on complex, difficult‐to‐understand interactions. In this commentary, we build on the innovations of the United States Fifth National Climate Assessment to suggest a framework for understanding and responding to complex climate challenges. This approach involves: (a) integration of disciplines and expertise to understand how intersectionality shapes complex climate impacts and the wide‐ranging effects of climate responses, (b) collaborations among diverse knowledge holders to improve responses and better encompass intersectionality, and (c) sustained experimentation with and learning about governance approaches capable of handling the complexity of climate change. Together, these three pillars underscore that usability of climate‐relevant knowledge requires transdisciplinary coordination of research and practice. We outline actionable steps for climate research to incorporate intersectionality, integration, and innovative governance, as is increasingly necessary for confronting climate complexity and sustaining equitable, ideally vibrant climate futures. Plain Language Summary: Climate impacts are complex, and prospects for climate responses depend on difficult‐to‐understand interactions. Lived experiences are increasingly revealing limits to what we in the scientific community have successfully modeled and ongoing challenges in how we help others understand the complexity of climate impacts and support decision‐making. Here, we chart a path for confronting the complexity of climate change with actionable advances in equity and governance research. Key Points: Climate impacts increasingly unfold in interlinked systems of people, nature, and infrastructureThe cascading consequences are revealing sometimes surprising connections and complex, difficult‐to‐understand interactionsWe suggest a research framework for climate complexity prioritizing intersectionality, integration, and innovative governance [ABSTRACT FROM AUTHOR]

On behalf of the journal, AGU, and the scientific community, we, the editors of Earth's Future, are delighted to publish the names of the 817 peer reviewers who provided 1,242 reviews for our journal in 2023 (italicized names have contributed three or more reviews). Your diligent efforts to provide timely comments on our submissions have significantly improved the manuscripts and elevated the scientific rigor of future research. As a unique transdisciplinary journal, Earth's Future delves into the state of the planet and its inhabitants, sustainable and resilient societies, the science of the Anthropocene, and predictions of our shared future through research articles, reviews, and commentaries. In the face of observed and anticipated global environmental and climatic changes, the need for high‐quality scientific theories, assessments, and projections about the future of our planet has never been more pressing. To safeguard research integrity in this crucial area, we rely on our reviewers' expertise and selfless cooperation. We extend our heartfelt thanks to each of the individuals listed below for their contributions to our journal and the broader scientific discourse. Your dedication is immensely appreciated. Plain Language Summary: We are delighted to publish the names of the 817 peer reviewers who submitted 1,242 reviews in 2023. We deeply appreciate your thoughtful comments and suggestions on manuscripts submitted to Earth's Future. Key Points: The editors thank the 2023 peer reviewers [ABSTRACT FROM AUTHOR]

The ability to reallocate water to higher‐value uses during drought is an increasingly important "soft‐path" tool for managing water resources in an uncertain future. In most of the Western United States, state‐level water market institutions that enable reallocation also impose substantial transaction costs on market participants related to regulatory approval and litigation. These transaction costs can be prohibitive for many participants in terms of both costs and lengthy approval periods, limiting transfers and reducing allocation efficiency, particularly during drought crises periods. This manuscript describes a mechanism to reduce transaction costs by adapting an existing form of informal leases to facilitate quicker and less expensive transfers among market participants. Instead of navigating the formal approval process to lease a water right, informal leases are financial contracts for conservation that enable more junior holders of existing rights to divert water during drought, thereby allowing the formal transfer approval process to be bypassed. The informal leasing approach is tested in the Upper Colorado River Basin, where drought and institutional barriers to transfers lead to frequent shortages for urban rights holders along Colorado's Front Range. Informal leases are facilitated via option contracts that include adaptive triggers and that define volumes of additional, compensatory, releases designed to mitigate impacts to instream flows and third parties. Results suggest that more rapid reallocation of water via informal leases could have resulted in up to $222 million in additional benefits for urban rights holders during the historical period 1950–2013. Plain Language Summary: In much of the developed world, there is little ability to sustainably manage water resources by building more dams or digging new wells. Water stressed regions are increasingly adapting to droughts through agreements to conserve or reallocate water between members of the community. In some places, markets make this easier by allowing users to buy and sell water. However, in most of the Western U.S., the legal system that approves these transactions makes them very costly and time consuming, reducing the benefits from trade. In particular, it is very hard to buy and sell short‐term leases. Here, we propose a new type of leasing contract, "informal leases," that avoid the legal system by relying on contractual agreements between water users. Instead of buying water via the legal system water users pay other users to conserve, coordinated through simple index contracts. When these contracts are designed correctly, they can perfectly recreate the effect of a formal water sale, for a fraction of the price. In this manuscript, we show how contracts for informal leases can be designed and evaluated, creating savings for water buyers/sellers, additional revenue for their neighbors, and a win/win response to environmental stress (for everyone except the lawyers). Key Points: Transaction costs related to regulatory approval are a significant impediment to water market leases in the Western United StatesInformal leases enable rapid short‐term water reallocation during drought while reducing transaction costsThe State of Colorado could have accrued $222 million in benefits using informal leases to reallocate water from irrigators to urban users [ABSTRACT FROM AUTHOR]