This README.txt file was generated on 2023-11-06 by Ariel Greenblat

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GENERAL INFORMATION
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1. Title of Dataset: Isotope signatures

2. Author Information
	A. Principal Investigator Contact Information
		Name: Ariel Greenblat
		Institution: Simon Fraser University, Earth Science Department
		Email: ariel_greenblat@gmail.com

	B.  Co-investigator Contact Information
		Name: Diana Allen
		Institution: Simon Fraser University, Earth Science Department
		Email: dallen@sfu.ca


        C.  Co-investigator Contact Information
		Name: Jesse Hahm
		Institution: Simon Fraser University, Earth Science Department
		Email: whahm@sfu.ca

3. Date of data collection: 

2021-11-17 to 2023-02-06

4. Geographic location of data collection: 

Lower Mainland British Columbia, Canada


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SHARING/ACCESS INFORMATION
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Greenblat, A., Allen, D., Hahm, J.(2023). Stable Water Isotopes of Precipitation, Surface Water and Groundwater in the North Alouette Watershed, BC, HydroShare, http://www.hydroshare.org/resource/1d5bbf7f88cb484e892ac9d97523d63c

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DATA & FILE OVERVIEW
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1. File List


   A. Isotope signatures:       
      Isotopes signatures of precipitation events collected in Pitt Meadows BC. AR absence and presence is also included with           associated Integrated Vapour Transport (IVT) amount for each event. Samples from the main stem (North Alouette), one of its tributaries and surrounding groundwater wells are also provided.   

δ18O is a measure of the ratio of stable isotopes oxygen-18 (18O) and oxygen-16 (16O)
δ2H is a measure of the ratio of stable isotopes hydrogen-2 (2H) and hydrogen-1 (1H)


   B. Map:       
      Map of sampling locations and surrounding area     


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METHODOLOGICAL INFORMATION
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Fifty-eight rain samples were collected and analyzed between November 2021 and February 2023. Samples were collected in Pitt Meadows, BC (49.221, -122.677, 7 metres above sea level (masl)) on a residential property. The first three rain samples collected on November 27, 2021; December 26, 2021, and January 12, 2022, were collected during the storm peak (i.e., mid-storm) from a roof gutter downspout. For the remainder of the study period (May 2022 to February 2023), a precipitation sampler, consisting of a Nalgene bottle fitted with a plastic funnel to minimize evaporation, was placed in an open, unobstructed area to avoid interception. A sample of all rain that accumulated over a 24-hour period (ending at 5 pm) was decanted into a 5 mL vial, capped and sealed (ensuring no headspace), and refrigerated until isotope analysis was conducted. In cases when AR-events spanned two precipitation collection periods, precipitation-weighted averages were determined using hourly precipitation data measured at the Pitt Meadows Climate Station 1106178 (49.208, -122.690, 5 masl) located 1.7 km southwest of the isotope collection station. 

The first three rain samples (November 27, 2021; December 26, 2021; January 12, 2022) were analyzed at the isotope lab at the University of Calgary using a Los Gatos Research Cavity Ring-Down Spectroscopy (CRDS) analyzer. The isotopic compositions of the remaining rain samples were analyzed on the Picarro® (L2140-i isotope and gas CRDS analyzer), Express Method, in Simon Fraser University’s Geography Department. An aliquot of each rain sample was transferred into a 2 mL glass vial and placed on the autosampler tray. Each vial was analyzed 6 times, by extracting 0.5 μL of sample. The first three readings were discarded to eliminate memory effect and the last three measurements were averaged. 

The elevation of the sample collections along the main steam range between 3.4 and 16.5 masl, elevation increasing eastward. The tributary sample is collected at 103 masl. Three groundwater samples were collected from each of a fractured sedimentary bedrock aquifer (average depth to water table (DTW) = 16.6 m), a confined sand and gravel aquifer in an area just outside the watershed (DTW = 2.5 m), and a fractured bedrock aquifer in the headwaters of the watershed (DTW = 52 m).