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1. Basin architecture controls on the chemical evolution and 4He distribution of groundwater in the Paradox Basin

   https://doi.org/10.1016/j.epsl.2022.117580  

   Tyne, R.L.; Barry, P.H.; Cheng, A.; Hillegonds, D.J.; Kim, J.-H.; McIntosh, J.C.; Ballentine, C.J. (July 2022, Earth and Planetary Science Letters)
2. The Lake Tahoe Basin Stream Catchment Database: A resource for water quality monitoring in the basin

   https://doi.org/10.17632/sn5dpnzc83.1  

   Dilts, Thomas; Blaszczak, Joanna (May 2025, Mendeley Data)

   Although the Lake Tahoe Basin and its receiving waterbody, Lake Tahoe, are intensively monitored, managed, and studied, there has been no centralized resource for evaluating variation in environmental characteristics among watersheds (i.e., catchments). To address this opportunity, we compiled and calculated 161 variables for 60 non-overlapping contiguous watersheds draining to Lake Tahoe . Watershed-scale variables include climatic, topographic, vegetation, edaphic, hydrologic, and anthropogenic characteristics. Data were downloaded from publicly-available sources including: the National Elevation Dataset, USDA SSURGO soils, Calfire FRAP dataset of fire perimeters, the National Land Cover Dataset, and the Rangeland Analysis Platform. We compiled data in a Geographic Information System at the scale of the watershed. Existing and custom scripts were used to process data and derive variables that could not be obtained from existing databases. These data will be useful for environmental managers and scientists who work in the Lake Tahoe Basin and can assist with future site selection intended to span environmental gradients. 

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3. Paleofluid Flow in the Paradox Basin: Introduction

   Barton, M.D.; Barton, I.; Thorson, J. (September 2018, Guidebook series)

   This field trip focuses on several of the classic Cu and U(-V) ore systems of the Colorado Plateau in the context of diverse geologic environments, processes, and consequences of fluid flow of the Paradox Basin. The Paradox Basin contains a >300-m.y. history of fluid flow and resource generation. Late Paleozoic development of a K-rich evaporitic foreland basin created a setting upon which later fluid-dominated processes generated economically significant accumulations of hydrocarbons, K-rich brines, CO2, and—most notably—metals including, significant deposits of Cu and some of the largest U and V resources of the United States. The sourcing and movement of fluids of diverse types and the resulting multiplicity of metasomatic features reflect a complex history starting with salt movement beginning in the Permian, sedimentation continuing intermittently into the Paleogene, distal manifestations of Cretaceous to Paleocene orogenesis, Cenozoic magmatism and, most recently, Neogene exhumation. In light of this broader context, we will examine Cu(-Ag) systems associated with salt anticlines at Paradox Valley (Cashin mine) and Lisbon Valley (Lisbon Valley mine), superimposed modern and ancient systems at Sinbad Valley, and contrasting U-V systems in the Jurassic Morrison Formation at Monogram Mesa (Uravan district) and Triassic Chinle Formation at Lisbon Valley (Big Indian district). In these areas, we consider the types and sources of various fluids (brines, hydrocarbons, meteoric), their solutes, the sequence of events, and links to overall basin evolution. A key objective of the trip is to use these examples and current interpretations to stimulate discussion and research about fluid flow and mass transfer in basinal settings. 

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4. Recent rainfall conditions in the Congo Basin

   https://doi.org/10.1088/1748-9326/ac61c4  

   Nicholson, Sharon E.; Klotter, Douglas A.; Zhou, Liming; Hua, Wenjian (May 2022, Environmental Research Letters)

   Abstract In the Congo Basin, a drying trend in the April–May–June rains prevailed between 1979 and 2014, accompanied by a decline in forest productivity. This article examines the subsequent years, in order to determine whether rainfall conditions have improved and to examine meteorological factors governing conditions in those years. It is shown that a wetter period, comparable to that of 1979–1993, spanned the years 2016–2020. However, the meteorological factors responsible for the wetter conditions appear to be significantly different from those related to the earlier wet period. The wetter conditions of 1979–1993 were associated with changes in the tropical Walker circulation, in moisture flux and flux divergence, and in Pacific sea-surface temperatures (SST), namely a warmer central and eastern Pacific and a cooler western Pacific, compared to the dry phase in 2000–2014. This resulted in a lower-than-average trans-Pacific SST gradient. In contrast, SSTs were almost ubiquitously higher in the 2016–2020 period than in either prior period. However, there was some reduction in the trans-Pacific gradient. The Walker circulation and moisture flux/flux divergence were not factors in this episode. The major factors provoking the return to wetter years appear to be an increase in convective available potential energy and in total column water vapor. This could be related to the general warming of the oceans and land. 

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5. Monsoon Dynamics in the Ganges-Brahmaputra-Meghna Basin

   https://doi.org/10.3390/CHyCle-2017-04865  

   Curtis, Scott; Crawford, Thomas; Munshi, Khaled; Paul, Bimal (September 2017, The 1st Electronic Conference on Hydrological Cycle (CHyCle-2017))

   A recently funded US National Science Foundation project seeks to investigate monsoon variability within the Ganges-Brahmaputra-Meghna (GBM) river basin as a potential predictor for annual shoreline erosion rates in the lower coastal delta region. Many previous studies have examined the interannual variability of South Asian precipitation either within political boundaries or across large spans of latitudes and longitudes, but few have taken a more hydrologic approach by analyzing the atmospheric-oceanic forcings that lead to precipitation falling only within the GBM basin. The temporal climate patterns would likely be different from previous studies and are hypothesized to have a more direct effect on outlet discharge and erosion rates. In the present study, mean monsoon precipitation (June-July-August-September) for the 2,309 0.25° grid boxes of the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) was extracted using geospatial methods. A Principal Component (PC) analysis was performed over the period 1983 to 2015. The first PC explains 88.7% of the variance and resembles climatology with the center of action over Bangladesh. The eigenvector shows a downward trend consistent with studies reporting a recent decline in monsoon rainfall. The second PC explains 2.9% of the variance and concentrates rainfall in the western portion of the basin. The 2nd component has greater temporal variability than the 1st component and an apparent decadal cycle. An analysis of global precipitation indicates that the rainfall patterns obtained within the GBM are localized. Surface and upper-air atmospheric height fields suggest the 2nd PC pattern is forced by a Rossby wave train stemming from the North Atlantic. 

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