Anne,
Another strategy is to use a sequential sampler. The one shown in the
auxiliary materials of the reference below is fitted with three heaters
and can collect 96 sequential snow (or surface water or groundwater
samples) at an interval as short as 10 minutes.
Two collectors have been collecting precipitation samples in Northern
California this last week, and two more will be set up this coming week.
Coplen, T. B., Neiman, P.J., White, A.B., Landwehr, J.M., Ralph, F.M., and
Dettinger, M.D., 2008, Extreme changes in stable hydrogen isotopes and
precipitation characteristics in a landfalling Pacific storm: Geophysical
Research Letters, v. 35, L21808, doi:10.1029/2008GL035481.
Ty
Tyler B. Coplen
U.S. Geological Survey
431 National Center
Reston, VA 20192
Tel: +1 703-648-5862
Email: [log in to unmask]
http://isotopes.usgs.gov/
From:
Lola Oliver <[log in to unmask]>
To:
[log in to unmask]
Date:
01/22/2010 01:32 PM
Subject:
Re: snow sampling question
Sent by:
Stable Isotope Geochemistry <[log in to unmask]>
Hi Anne,
We collect snow routinely for isotope analysis (originally on a mass
spec, now on the Picarro). Our field guy collects fresh snow weekly
from flat platforms (usually just plywood on a stand in the open)
into a 3" diameter jar with a tight lid. He brushes off the rest of
the snow so the platform only collects fresh snow. The sample is put
in a refrigerator to thaw overnight and then poured into exetainer
vials and capped and put back into the refrigerator until
analysis. I use the exetainer vials because it has a tight-fitting
cap, and because I can fill it to the top to eliminate air
space. This method has worked well for the last 5 years. For the
Picarro, be careful that the sample doesn't have any particles in it
that might foul the needle. You should be able to see anything that
would cause a problem. Taking the sample from the very top of the
exetainer works, but you could also filter the snow water into the
exetainer through quartz wool.
Any method that 1) only collects current snow, 2) keeps the snow
contained as it thaws and 3) keeps the melt water from evaporating
until analysis, should be fine.
I like snow. It's easy.
Lola.
.
At 01:22 AM 1/22/2010, you wrote:
>Hello,
>
>I will be collecting snow samples for water isotope analyses using a
>Picarro instrument. I would appreciate information on what sort of
>sample vials to use and any additional information on snow sample
>collection techniques.
>
>Thank you,
>Anne
>
>************************************************
>Anne Nolin
>Landolt et Cie Chair for Sustainable Futures, Ecole Polytechnique
>Federale de Lausanne and
>Associate Professor, Department of Geosciences
>Wilkinson 104
>Oregon State University
>541-737-8051 (office)
>541-737-1200 (fax)
>http://www.geo.oregonstate.edu/people/faculty/nolina.htm
>[log in to unmask]
>skype: AnneNolin; 541-497-7213
>************************************************
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