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Open-source designs for turbidity and depth sensors are becoming increasingly capable and available, but the knowledge required to construct them limits their use compared to expensive, commercial sensors. Here, we present an open-source optical backscatter and water pressure sensor that can be ordered almost fully assembled, requires no coding to deploy, and costs approximately $50 USD. We share three examples of these sensors’ ability to facilitate new research. First, we observed complex changes in spatial and temporal patterns of suspended sediment transport in the Arctic Sagavanirktok River using a network of sensors. Second, we measured turbidity during the freeze-up period in the Tanana River, a period of high risk to sensors. Last, we built and deployed sensors with middle-school students to monitor turbidity under full ice cover on the Tanana River. The success of open-source sensors in these examples shows a marked increase in scale and accessibility of river science.

The primary goal of the GlueX experiment at Jefferson Lab is to map the spectrum of light hybrid mesons. GlueX, which has a linearly polarized photon beam and a large acceptance for both charged and neutral particles, has access to both the neutral, γp → ηπ0 p, and charged, γp → ηπ−∆++, final states. These proceedings will discuss the amplitude analysis of ηπ channels at GlueX with a focus on the study of the production of the a2(1320) meson as function of Mandelstam t.

The change in climate, characterized by spatial and temporal variations in precipitation and temperature, significantly impacts the hydrological processes and water resources availability. Quantifying long-term changes in climatic variables and their effect on streamflow are crucial for understanding watershed hydrology and developing effective climate adaptation and water management strategies. In this study, we aim to quantify the changes in precipitation, temperature, and streamflow over the last 70 years (1950-2020) for two glacierized catchments in Nepal: Marsyangdi and Budigandaki River Basins. We utilize a distributed hydrological model (HYMOD_DS) forced by the most recent release of the ERA5 Land reanalysis product. Our investigation focuses on evaluating the impact of spatiotemporal changes in precipitation phases (either snow or rainfall) on streamflow characteristics. Specifically, we analyze the temporal trends and changes in the distribution of snow and rainfall and resulting streamflow separated into surface runoff and baseflow at daily and seasonal scales. The ERA5 Land reanalysis indicates a decrease in mean annual total precipitation for the period 1950-1980 and an increasing trend afterward. Annual mean temperature exhibits a rising trend for the entire period. Streamflow simulations for both basins revealed a significantly increased total flow over the last 20 years, primarily due to an increase in rainfall-induced streamflow. The results from this study will provide critical insight into the hydrology of glacierized basins and serve as a reference for water resources planning under climate change.

Cities have historically developed close to rivers and coasts, increasing human exposure to flooding. That exposure is exacerbated by changes in climate and population, and by urban encroachment on floodplains. Although the mechanisms of how urbanization affects flooding are relatively well understood, there have been limited efforts to assess the magnitude of floodplain encroachment globally and how it has changed in both space and time. Highly resolved global datasets of both flood risk and changes in urban area from 1985-2015 are now available, enabling the reconstruction of the history of floodplain encroachment at high spatial resolutions. Here we show that the urbanized area in floodplains that have an average probability of flooding of 1/100 years, has almost doubled since 1985. Further, the rate of urban expansion into these floodplains increased by a factor of 1.5 after the year 2000. We also find that urbanization rates were highest in the most hazardous areas of floodplains, with population growth in these urban floodplains suggesting an accompanying increase in population density. These results reveal the scope, trajectory and extent of global floodplain encroachment. With tangible implications for flood risk management, these data can be directly used with integrated models to assess adaptation pathways for urban flooding.

Many excited nucleon states ( $$N^{*}$$ s) predicted by quark models, but not observed in $$\pi N$$ channels, are expected to couple strongly to kaon–hyperon (KY) channels. While in the last decade data have been published for KY photoproduction off the proton, data off the neutron are scarce. In this paper we present preliminary results for the polarization observables P, $$C_x$$ , and $$C_z$$ for the reaction $$\gamma d\rightarrow K^{0}\varLambda (p)$$ , where (p) denotes the spectator proton. The observables cover photon energies, $$E_{\gamma }$$ , between 0.9 and 2.6 GeV and kaon center-of-mass angles, $$\cos \theta _{K^{0}}^{{ CM}}$$ , between $$-\,0.9$$ and 1. The data were collected in experiment E06-103 (g13) with the CLAS detector at the Thomas Jefferson National Accelerator Facility using a circularly-polarized photon beam and an unpolarized liquid deuterium target. We also discuss the effect of neutron binding on the observables. Our study is part of a broader effort by the g13 group to provide cross sections and polarization observables for meson photoproduction off the neutron and is expected to have a significant impact on the $$N^{*}$$ research.