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1. A Comprehensive Overview of Unit-Level Modeling of Survey Data for Small Area Estimation Under Informative Sampling

   https://doi.org/10.1093/jssam/smad020  

   Parker, Paul A; Janicki, Ryan; Holan, Scott H (June 2023, Journal of Survey Statistics and Methodology)

   Abstract Model-based small area estimation is frequently used in conjunction with survey data to establish estimates for under-sampled or unsampled geographies. These models can be specified at either the area-level, or the unit-level, but unit-level models often offer potential advantages such as more precise estimates and easy spatial aggregation. Nevertheless, relative to area-level models, literature on unit-level models is less prevalent. In modeling small areas at the unit level, challenges often arise as a consequence of the informative sampling mechanism used to collect the survey data. This article provides a comprehensive methodological review for unit-level models under informative sampling, with an emphasis on Bayesian approaches. 

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2. River effects on sea-level rise in the Río de la Plata estuary during the past century

   https://doi.org/10.5194/os-19-57-2023  

   Piecuch, Christopher G. (January 2023, Ocean Science)

   Abstract. Identifying the causes for historical sea-level changes in coastal tide-gauge records is important for constraining oceanographic, geologic, and climatic processes. The Río de la Plata estuary in South America features the longest tide-gauge records in the South Atlantic. Despite the relevance of these data for large-scale circulation and climate studies, the mechanisms underlying relative sea-level changes in this region during the past century have not been firmly established. I study annual data from tide gauges in the Río de la Plata and stream gauges along the Río Paraná and Río Uruguay to establish relationships between river streamflow and sea level over 1931–2014. Regression analysis suggests that streamflow explains 59 %±17 % of the total sea-level variance at Buenos Aires, Argentina, and 28 %±21 % at Montevideo, Uruguay (95 % confidence intervals). A long-term streamflow increase effected sea-level trends of 0.71±0.35 mm yr−1 at Buenos Aires and 0.48±0.38 mm yr−1 at Montevideo. More generally, sea level at Buenos Aires and Montevideo respectively rises by (7.3±1.8)×10-6 m and (4.7±2.6)×10-6 m per 1 m3 s−1 streamflow increase. These observational results are consistent with simple theories for the coastal sea-level response to streamflow forcing, suggesting a causal relationship between streamflow and sea level mediated by ocean dynamics. Findings advance understanding of local, regional, and global sea-level changes; clarify sea-level physics; inform future projections of coastal sea level and the interpretation of satellite data and proxy reconstructions; and highlight future research directions. Specifically, local and regional river effects should be accounted for in basin-scale and global mean sea-level budgets as well as reconstructions based on sparse tide-gauge records. 

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3. Deglacial perspectives of future sea level for Singapore

   https://doi.org/10.1038/s43247-023-00868-5  

   Shaw, Timothy A.; Li, Tanghua; Ng, Trina; Cahill, Niamh; Chua, Stephen; Majewski, Jedrzej M.; Nathan, Yudhishthra; Garner, Gregory G.; Kopp, Robert E.; Hanebuth, Till J.; et al (December 2023, Communications Earth & Environment)

   Abstract Low elevation equatorial and tropical coastal regions are highly vulnerable to sea level rise. Here we provide probability perspectives of future sea level for Singapore using regional geological reconstructions and instrumental records since the last glacial maximum ~21.5 thousand years ago. We quantify magnitudes and rates of sea-level change showing deglacial sea level rose from ~121 m below present level and increased at averaged rates up to ~15 mm/yr, which reduced the paleogeographic landscape by ~2.3 million km 2 . Projections under a moderate emissions scenario show sea level rising 0.95 m at a rate of 7.3 mm/yr by 2150 which has only been exceeded (at least 99% probability) during rapid ice mass loss events ~14.5 and ~9 thousand years ago. Projections under a high emissions scenario incorporating low confidence ice-sheet processes, however, have no precedent during the last deglaciation. 

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4. Annual crop-specific management history of phosphorus fertilizer input (CMH-P) in the croplands of United States from 1850 to 2022: Application rate, timing, and method

   https://doi.org/10.5281/zenodo.10700821  

   Cao, Peiyu; Yi, Bo; Bilotto, Franco; Gonzalez_Fischer, Carlos; Herrero, Mario; Lu, Chaoqun (August 2024, Zenodo)

   This dataset presents spatiotemporal dynamics of phosphorus (P) fertilizer management (application rate, timing, and method) at a 4km × 4 km resolution in agricultural land of the contiguous U.S. from 1850 to 2022. By harmonizing multiple data sources, we reconstructed the county-level crop-specific P fertilizer use history. We then spatialized and resampled P fertilizer use data to 4 km × 4 km gridded maps based on historical U.S. cropland distribution and crop type database developed by Ye et al. (2024). This dataset contains (1) P fertilizer total consumption and mean application rate at the national level (Tabular); (2) P fertilizer consumption of 11 crops at the state level (Tabular); (3) P fertilizer consumption of permanent pasture (Tabular); (4) P fertilizer consumption of non-farm at the state level (Tabular); (5) P fertilizer application rate of 11 crop types at the state level (Tabular); (6) P fertilizer application rate of 11 crop types at the county level (Tabular); (7) P fertilizer application timing ratio at the state level (Tabular); (8) P fertilizer application method ratio at the state level (Tabular); (9) Gridded maps of P fertilizer application rate based on state-level data; (10) and (11) Gridded maps of P fertilizer application rate based on county-level data; (12)-(20) Gridded maps of P fertilizer application rate for each crop. A detailed description of the data development processes, key findings, and uncertainties can be found in Cao, P., Yi, B., Bilotto, F., Gonzalez Fischer, C., Herrero, M., Lu, C.: Crop-specific Management History of Phosphorus fertilizer input (CMH-P) in the croplands of United States: Reconciliation of top-down and bottom-up data sources, is under review for the journal Earth System Science Data (ESSD). https://essd.copernicus.org/preprints/essd-2024-67/#discussion.  This work is supported by the Iowa Nutrient Research Center, the ISU College of Liberal Arts and Sciences Dean's Faculty Fellowship, and NSF CAREER grant (1945036). 

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5. Several levels of theory for description of isotope effects in ozone

   Babikov, Dmitri (May 2019, 50th Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics APS Meeting)

   We developed a multi-level theory for description of the intricate isotope effect in ozone. At 0th level of theory the role of molecular symmetry is taken into account. Although the important factors of 1/2 appear in seven different places in the formalism, this level of theory does not lead to any isotope effect. At the 1st level the effect of atomic masses is introduced to elucidate the roles of vibrational zero-point energies and rotational excitations. It is found that averaging over thermal distribution smooths isotopic differences and leads to a small net effect. At the 2nd level the process is assumed to proceed through independent diabatic ro-vibrational channels, which permits to determine contribution of shape resonances populated by tunneling. Resultant isotope effects do not look like experiment and the rate coefficient is too small. At the 3rd level the role of Feshbach resonances is determined, by accurate close-coupling calculations using hyper-spherical coordinates, adaptive grids, sequential diagonalization truncation technique and complex absorbing potential. Comparison with experiment is presented. Refs: J. Phys. Chem. A 122, 9177 (2018); J. Chem. Phys. 149, 164302 (2018). 

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