Monitoring of tritium concentration in Hanoi's precipitation from 2011 to 2016.

Tritium is a radioisotope of hydrogen and a component of the water molecule. It is a marker for reservoirs such as the stratosphere, troposphere, and oceans involved in the hydrological cycle. Tritium monitoring is an essential research tool in hydro-climate, dating for water and recharge groundwater. The Isotope Hydrology Laboratory has collected monthly precipitation samples in Hanoi for tritium concentration analysis. This paper reports the tritium concentrations in precipitation in the city from 2011 to 2016. The results show that monthly tritium concentration reached a maximum of 7.07 Tritium Units (TU) in August 2011. The mean annual tritium concentration stabilized from 2.03 to 3.36 TU. It suggests that tritium in monitoring station precipitation is predominantly natural. The seasonal variation trend of H in precipitation at the Hanoi station is similar to those monitored at the Hong Kong station. The correlation of tritium and rainfall was also estimated.