Brief Research Report ARTICLE
Assessing the sampling quality of a low-tech low-budget volume-based rainfall sampler for stable isotope analysis
- 1Department of Physical Geography, Stockholm University, Sweden
- 2Bolin Centre for Climate Research, Stockholm University, Sweden
- 3Institute for Atmospheric and Climate Science, Department of Environmental Systems Sciences, ETH Zurich, Switzerland
- 4Geophysical Institute, Faculty of Mathematics and Natural Sciences, University of Bergen, Norway
- 5Bjerknes Centre for Climate Research, University of Bergen, Norway
- 6Department of Geography, Faculty of Mathematics and Natural Sciences, University of Zurich, Switzerland
- 7Department of Earth Sciences, Uppsala University, Sweden
To better understand the small-scale variability of rainfall and its isotopic composition it is advantageous to utilize rain samplers which are at the same time low-cost, low-tech, robust, and precise with respect to the collected rainwater isotopic composition. We assessed whether a self-built version of the Kennedy sampler is able to collect rainwater consistently without mixing with antecedent collected water. We called the self-built sampler made from honey jars and silicon tubing the Zurich sequential sampler. Two laboratory experiments show that high rainfall intensities can be sampled and that the volume of water in a water sample originating from a different bottle was generally less than 1 ml. Rainwater was collected in 5mm increments for stable isotope analysis using three (year 2011) and five (years 2015 and 2016) rain samplers in Zurich (Switzerland) during eleven rainfall events. The standard deviation of the total rainfall amounts between the different rain gauges was <1%. The standard deviation of 18O and 2H among the different sequential sampler bottles filled at the same time was generally <0.3‰ for 18O and <2‰ for 2H (8 out of 11 events). Larger standard deviations could be explained by leaking bottle(s) with subsequent mixing of water with different isotopic composition of at least one out of the five samplers. Our assessment shows that low-cost, low-tech rain samplers, when well maintained, can be used to collect sequential samples of rainfall for stable isotope analysis and are therefore suitable to study the spatio-temporal variability of the isotopic composition of rainfall.
Keywords: sequential rain water sampler, rainfall and its isotopic composition, stable isotopes (18O and 2H), field test, low-cost/low-tech self-built sampler, laboratory experiments
Received: 31 Jan 2019;
Accepted: 02 Sep 2019.
Copyright: © 2019 Fischer, Aemisegger, Graf, Sodemann and Seibert. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Benjamin M. Fischer, Department of Physical Geography, Stockholm University, Stockholm, Sweden, email@example.com