Unlocking the Climate Record Stored within Mars’ Polar Layered Deposits

In the icy beds of its polar layered deposits (PLD), Mars likely possesses a record of its recent climate history, analogous to terrestrial ice sheets that contain records of Earth's past climate. Both northern and southern PLDs store information on the climatic and atmospheric state during the deposition of each layer (WPs: Becerra et al.; Smith et al). Reading the climate record stored in these layers requires detailed measurements of layer composition, thickness, isotope variability, and near-surface atmospheric measurements. We identify four fundamental questions that must be answered in order to interpret this climate record and decipher the recent climatic history of Mars: 1. Fluxes: What are the present and past fluxes of volatiles, dust, and other materials into and out of the polar regions? 2. Forcings: How do orbital/axial forcing and exchange with other reservoirs affect those fluxes? 3. Layer Processes: What chemical and physical processes form and modify layers? 4. Record: What is the timespan, completeness, and temporal resolution of the climate history recorded in the PLD? In a peer reviewed report (1), we detailed a sequence of missions, instruments, and architecture needed to answer these questions. Here, we present the science drivers and a mission concept for a polar lander that would enable a future reading of the past few million years of the Martian climate record. The mission addresses as-yet-unachieved science goals of the current Decadal Survey and of MEPAG for obtaining a record of Mars climate and has parallel goals to the NEXSAG and ICE-SAG reports

The Sign of the Orientation Parameter in Electron-Photon Coincidence Experiments

Steph et al. (1980) have proposed a model for the orientation parameter which attributes positive transfer of angular momentum to long-range attractive atomic polarisation potentials and negative transfer to electron-electron repulsion. This model is based on a classical grazing picture for the collision and has received considerable attention due to its intuitive appeal. The authors show that quantal calculations reveal that the physical effects of this model are not of primary importance in determining the sign of the orientation parameter

Nearshore fish community changes along the Toronto waterfront in accordance with management and restoration goals: Insights from two decades of monitoring.

Aquatic habitat in the Greater Toronto Area has been subject to anthropogenic stressors. The subsequent aquatic habitat degradation that followed led to the Toronto and Region waterfront being listed as an Area of Concern in 1987. Thus, extensive shoreline and riparian habitat restoration have been implemented as part of the Toronto and Region Remedial Action Plan in conjunction with local stakeholders, ministries, and NGOs in an overall effort to increase fish, bird, and wildlife habitat. A key aspect of current fish habitat restoration efforts, monitored by Toronto and Region Conservation Authority, is to account for long-term community changes within the target ecosystem to better understand overall changes at a larger spatial scale. Here we use electrofishing data from the past 20 years with over 100,000 records and across 72km of coastline to show how declines and fluctuations in fish biomass and catch along the waterfront are driven by a few individual species across three main ecotypes, such as coastal wetlands, embayments, and open coast sites, with the remaining species showing a high level of stability. Using community traits and composition for resident species we demonstrate native warmwater species have become more dominant along the waterfront in recent years, suggesting that restoration efforts are functioning as intended. Additionally, piscivore and specialist species have increased in their relative biomass contribution, approaching existing restoration targets. Altogether this waterfront-wide evaluation allows us to detect overall changes along the waterfront and can be beneficial to understand community changes at an ecosystem level when implementing and monitoring restoration projects

Chemical weathering processes in the Great Artesian Basin: Evidence from lithium and silicon isotopes

Variations in lithium and silicon isotope ratios in groundwaters of the Great Artesian Basin in Australia, and the causes of these variations, have been explored. The chemistries of Li and Si in groundwater are influenced by the dissolution of primary phases, the formation of secondary minerals, and the reaction of solid phases with dissolved constituents, while isotopic variations are generated by uptake into clays, which preferentially incorporate the light isotopes. The lithium isotopic composition (expressed as View the MathML source?Li7) of the groundwaters ranges from +9 to +16‰+16‰, and clearly reflects changes in aquifer conditions. Reaction-transport modelling indicates that changes in Li concentrations are principally controlled by the ratio of the weathering rate of primary minerals to the precipitation rate of secondary minerals, whereas View the MathML source?Li7 is affected by the extent of isotope fractionation during secondary mineral formation (which is dependent on mineralogy). The patterns of groundwater Si concentrations and View the MathML source?Si30 values versus flow distance suggest that Si is at steady state in the aquifer. The View the MathML source?Si30 value of most of the groundwater samples is close to ?1‰?1‰, which is significantly lower than the View the MathML source?Si30 value of the reservoir rocks (?0‰?0‰). Since precipitation of clays preferentially removes the light Si isotopes from solution, the most plausible explanation for these low groundwater View the MathML source?Si30 values is addition of Si by dissolution of isotopically light secondary minerals. These data, together with model calculations, show that Li isotopes are extremely sensitive to changes in the chemical and physical conditions in the aquifer, whereas Si is not. Importantly, the model suggests that even in large aquifers with long fluid residence times, where steady-state would be expected to be reached, the concentrations and isotopic fractionation of trace elements are not controlled by Li adsorption. The model developed here provides a basis for using Li isotopes measured in groundwaters and surface waters to constrain weathering processes

Empowerment of Whom and for What? Financial Literacy Education and the New Regulation of Consumer Financial Services

Financial regulators in many states recently have obtained statuory mandates to enhance consumer financial literacy. This paper investicages the development of policy pursuant to such mandates in the UK and Canada to identify how national regulators in both countries represent financial market place. It finds that regulators in both countries represent financial education as empowerment and responsible consumer behaviour. The paper rekates the tension between empowerment and responsibilization aspects of literacy enhancement to policy goals of expectations of protection. It raises questions about regulators' use of consumer education to responsiblize consumption of financial products and calls for further research on the international growth of financial literacy education as a regulatory project

Towards effective ecological restoration: Investigating knowledge co‐production on fish–habitat relationships with Aquatic Habitat Toronto

Abstract For decades, the working paradigm for ecological restoration was independent operation of knowledge generators (researchers and scientists) and knowledge users (decision makers and practitioners), resulting in a knowledge–action gap. Knowledge co‐production is a collaborative process where research is conducted in a respectful and engaging manner with continuous knowledge exchange and heralded as a means of bridging the divide. Aquatic Habitat Toronto (AHT) is a unique consensus‐based partnership with diverse member agencies that engage in restoration ecology and practice along the Toronto Waterfront of Lake Ontario, Canada. Here, we examine the process that AHT uses to enable knowledge co‐production and identify associated benefits and challenges. Benefits to AHT's consensus‐based partnership include advanced notice of projects, access to diverse expertise and local knowledge, increased understanding of fish habitat, adoption of novel restoration techniques and more effective restoration and improved knowledge exchange, collectively mitigating the knowledge–action divide. Challenges of knowledge co‐production facilitated by AHT include consistent agency participation and meaningful engagement, closed or exclusive networks, time commitments and limited financial resources, evolving political landscapes, stability of funding cycles and issues stemming from varying goals and relevancy. Key recommendations for ensuring that knowledge co‐production results in actionable science and for maximizing the effectiveness of ecological restoration using AHT's format include securing long‐term and stable funding, developing relationships across agencies and allied partners, engaging early, outlining goals/objectives collaboratively, conducting before and after scientific monitoring, minimizing personal biases, periodically reviewing partnerships to maximize inclusivity, sharing successes (and failures) broadly, and providing open data. AHT embraces an approach that includes integrated planning with multi‐jurisdictional support with diverse partners at a tractable scale and we argue that this should be the standard model of aquatic ecosystem management