Major ion concentrations and the inorganic carbon chemistry of the Humber rivers

1997 ◽  
Vol 194-195 ◽  
pp. 285-302 ◽  
Author(s):  
Helen P. Jarvie ◽  
Colin Neal ◽  
David V. Leach ◽  
Geoffery P. Ryland ◽  
W.Alan House ◽  
...  
1999 ◽  
Vol 29 (3) ◽  
pp. 245-255 ◽  
Author(s):  
Malcolm R. Reid ◽  
Jonathan P. Kim ◽  
Keith A. Hunter

2008 ◽  
Vol 4 (1) ◽  
pp. 173-211
Author(s):  
E. Dietze ◽  
A. Kleber ◽  
M. Schwikowski

Abstract. El Niño-Southern Oscillation (ENSO) is an important element of earth's ocean-climate system. To further understand its past variability, proxy records from climate archives need to be studied. Ice cores from high alpine glaciers may contain high resolution ENSO proxy information, given the glacier site is climatologically sensitive to ENSO. We investigated signals of ENSO in the climate of the subtropical Andes in the proximity of Cerro Tapado glacier (30°08' S, 69°55' W, 5550 m a.s.l.), where a 36 m long ice core was drilled in 1999 (Ginot, 2001). We used annual and semi-annual precipitation and temperature time series from regional meteorological stations and interpolated grids for correlation analyses with ENSO indices and ice core-derived proxies (net accumulation, stable isotope ratio δ18O, major ion concentrations). The total time period investigated here comprises 1900 to 2000, but varies with data sets. Only in the western, i.e. Mediterranean Andes precipitation is higher (lower) during El Niño (La Niña) events, especially at higher altitudes, due to the latitudinal shift of frontal activity during austral winters. However, the temperature response to ENSO is more stable in space and time, being higher (lower) during El Niño (La Niña) events in most of the subtropical Andes all year long. From a northwest to southeast teleconnection gradient, we suggest a regional water vapour feedback triggers temperature anomalies as a function of ENSO-related changes in regional pressure systems, Pacific sea surface temperature and tropical moisture input. Tapado glacier ice proxies are found to be predominantly connected to eastern Andean summer rain climate, which contradicts previous studies and the modern mean spatial boundary between subtropical summer and winter rain climate derived from the grid data. The only ice core proxy showing a response to ENSO is the major ion concentrations, via local temperature indicating reduced sublimation and mineral dust input during El Niño years.


2016 ◽  
Vol 11 (2) ◽  
pp. 448-458 ◽  
Author(s):  
Linhua Sun ◽  
Song Chen ◽  
Herong Gui

Water source identification is important for water hazard controlling in coal mines. In this study, major ion concentrations of the groundwater collected from four representative aquifer systems in the Baishan coal mine, northern Anhui Province, China, have been analysed by a series of statistical methods. The results indicate that the major ion concentrations of the groundwater from different aquifer system are different with each other, and provided the possibility of water source identification based on hydrochemistry. Factor analysis indicates that these differences are controlled by different types of water rock interactions. The analysis based on US Environmental Protection Agency (EPA) Unmix model identified three sources (weathering of silicate minerals, dissolution of carbonate and evaporate minerals) responsible for the hydrochemical variations of the groundwater. Also, it shows that their contributions for the groundwater in different aquifer systems vary considerably. Based on these variations and on step by step analysis, the source aquifer system for the groundwater samples with unknown source has been determined and, similar to the result obtained by the cluster and discriminant analysis. Therefore, EPA Unmix model can be applied for water source identification in coal mine, as it can provide information about water rock interaction and water source identification simultaneously.


2015 ◽  
Vol 39 (1) ◽  
pp. 27-39 ◽  
Author(s):  
Triona McGrath ◽  
Evin McGovern ◽  
Rachel R. Cave ◽  
Caroline Kivimäe

2012 ◽  
Vol 212-213 ◽  
pp. 362-365 ◽  
Author(s):  
Lin Hua Sun ◽  
He Rong Gui

Major ion concentrations of twenty groundwater samples from two deep seated aquifers (coal bearing-GC and limestone-LC) are analyzed for identify the differences between them and the source of ions. The results suggest that they are moderate to highly mineralized water with their average TDS values are 2444 (GC) and 1178 (LC) mg/L. LCs show lower Na but much higher Ca and Mg concentrations relative to GCs. Saturation indexes and principle component analysis, as well as mole ratios between Na and Cl, Ca and SO4, Ca and HCO3 indicate that they have multi sources with incorporation of halite and albite for Na, calcite, dolomite and gypsum for Ca, pyrite and gypsum for SO4.


2020 ◽  
Vol 17 (14) ◽  
pp. 3837-3857
Author(s):  
Claudine Hauri ◽  
Cristina Schultz ◽  
Katherine Hedstrom ◽  
Seth Danielson ◽  
Brita Irving ◽  
...  

Abstract. The coastal ecosystem of the Gulf of Alaska (GOA) is especially vulnerable to the effects of ocean acidification and climate change. Detection of these long-term trends requires a good understanding of the system’s natural state. The GOA is a highly dynamic system that exhibits large inorganic carbon variability on subseasonal to interannual timescales. This variability is poorly understood due to the lack of observations in this expansive and remote region. We developed a new model setup for the GOA that couples the three-dimensional Regional Oceanic Model System (ROMS) and the Carbon, Ocean Biogeochemistry and Lower Trophic (COBALT) ecosystem model. To improve our conceptual understanding of the system, we conducted a hindcast simulation from 1980 to 2013. The model was explicitly forced with temporally and spatially varying coastal freshwater discharges from a high-resolution terrestrial hydrological model, thereby affecting salinity, alkalinity, dissolved inorganic carbon, and nutrient concentrations. This represents a substantial improvement over previous GOA modeling attempts. Here, we evaluate the model on seasonal to interannual timescales using the best available inorganic carbon observations. The model was particularly successful in reproducing observed aragonite oversaturation and undersaturation of near-bottom water in May and September, respectively. The largest deficiency in the model is its inability to adequately simulate springtime surface inorganic carbon chemistry, as it overestimates surface dissolved inorganic carbon, which translates into an underestimation of the surface aragonite saturation state at this time. We also use the model to describe the seasonal cycle and drivers of inorganic carbon parameters along the Seward Line transect in under-sampled months. Model output suggests that the majority of the near-bottom water along the Seward Line is seasonally undersaturated with respect to aragonite between June and January, as a result of upwelling and remineralization. Such an extensive period of reoccurring aragonite undersaturation may be harmful to ocean acidification-sensitive organisms. Furthermore, the influence of freshwater not only decreases the aragonite saturation state in coastal surface waters in summer and fall, but it simultaneously decreases the surface partial pressure of carbon dioxide (pCO2), thereby decoupling the aragonite saturation state from pCO2. The full seasonal cycle and geographic extent of the GOA region is under-sampled, and our model results give new and important insights for months of the year and areas that lack in situ inorganic carbon observations.


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