Mixing processes between thermal waters and non-thermal waters: a case study in Mexico

Abstract. The behavior of the Extra-tropical Transition Layer (ExTL) in the lowermost stratosphere is investigated using a Chemistry Transport Model (CTM) and analyses derived from assimilation of MLS (Microwave Limb Sounder) O3 and MOPITT (Measurements Of Pollution In The Troposphere) CO data. We use O3-CO correlations to quantify the effect of the assimilation on the height and depth of the ExTL. We firstly focus on a Stratosphere-Troposphere Exchange (STE) case study which occurred on 15 August 2007 over the British Isles (50° N, 10° W). We also extend the study at the global scale for the month of August 2007. For the STE case study, MOPITT CO analyses have the capability to sharpen the ExTL distribution whereas MLS O3 analyses provide a tropospheric expansion of the ExTL distribution with its maximum close to the thermal tropopause. When MLS O3 and MOPITT CO analyses are used together, the ExTL shows more realistic results and matches the thermal tropopause. At global scale, MOPITT CO analyses still show a sharper chemical transition between stratosphere and troposphere than the free model run. MLS O3 analyses move the ExTL toward the troposphere and broaden it. When MLS O3 analyses and MOPITT CO analyses are used together the ExTL matches the thermal tropopause poleward of 50°. This study shows that data assimilation can help overcome the shortcomings associated with a relatively coarse model resolution. The ExTL spread is larger in the Northern Hemisphere than the Southern Hemisphere suggesting that mixing processes are more active in the UTLS in the Northern Hemisphere than in the Southern Hemisphere. This work opens perspectives for studying the seasonal variations of the ExTL at extra-tropical latitudes.

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Qualitative and Comparative Study of Different Methods of Interpolation for the Mapping of Groundwater Salinity: Case Study of Thermal Waters Used for Irrigation in Northeastern Algeria

Journal of Geoscience and Environment Protection ◽

10.4236/gep.2021.97008 ◽

2021 ◽

Vol 09 (07) ◽

pp. 115-132

Author(s):

Touhami Feraga ◽

Séverin Pistre

Keyword(s):

Comparative Study ◽

Thermal Waters ◽

Groundwater Salinity ◽

Northeastern Algeria

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Natural Radioactivity in Thermal Waters: A Case Study from Poland

Energies ◽

10.3390/en14030541 ◽

2021 ◽

Vol 14 (3) ◽

pp. 541

Author(s):

Chau Nguyen Dinh ◽

Jakub Nowak

Keyword(s):

Natural Radioactivity ◽

Transport Model ◽

Thermal Waters ◽

Chemical Compositions ◽

Wide Range ◽

Physical And Chemical ◽

Radium Activity ◽

Hydrochemical Types ◽

Chemical Water

A natural radioactivity in thermal water was investigated based on 19 selected thermal waters from Poland. The analysed results show that the radionuclides’ concentrations in the study waters vary over a wide range. The temperature of the waters varies from above 20 °C to above 80 °C. The waters are characterised by different mineralisation, chemical compositions, and belong to different hydrochemical types. There is a good correlation between the water temperature and the depths of the aquifer formations occurrence, suggesting the thermal energy originates from the thermal geogradient. The concentration of radium is well correlated with the water mineralisation. The ratio of radium activity (226Ra/228Ra) in groundwater relates not only the ratio of uranium activity to that of thorium (238U/232Th) in aquifer formation, but also depends on the physical and chemical water properties. Based on the concentration of radon and its transport model, the radiation exposures due to inhalation of 222Rn and its progeny for employees and clients of the spa were assessed. The use of the thermal waters as a drinking resource may be problematic due to the possibility of exceeding the recommended annual committed effective dose 0.1 mSv.

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